Investigación: Polímero baquelita

UNIVERSIDADAUTÓNOMA DEL ESTADO DE MÉXICO FACULTAD DE QUÍMICA PROGRAMA EDUCATIVO DE INGENIERO QUÍMICO “POLÍMERO: BAQUELITA (ADELANTO)” TRABAJO QUE PRESENTA: ALVIRDE GENARO SELENE MARITZA CAMACHO VARA BRYAN CONTRERAS MARTINEZ MIRIAM GONZALEZ GONZALEZ CESAR XINGU VILCHIZ JAZMIN “QUÍMICA ORGÁNICA HETEROALIFÁTICA Y POLÍMEROS” Profesor: Dra. SUSANA HERNÁNDEZ LÓPEZ Lugar y Fecha de presentación TOLUCA, ESTADO DE MÉXICO. 23 DE NOVIEMBRE DE 2015 1 JUSTIFICACIÓN En la industria química, las cetonas y los aldehídos se utilizan como disolventes, como sustancias iniciales y como reactivos para la síntesis de otros productos. A pesar de que el formaldehído se suele encontrar en solución (formol), utilizado para preservar muestras biológicas, la mayoría de los cuatro millones de toneladas de formaldehído que se producen cada año se utilizan para la obtención de Bakelita®, resinas de fenol-formaldehído, pegamentos de urea-formaldehído y otros productos poliméricos.1 Los plásticos y resinas de fenol-formaldehído (también denominados jlmólicos) tienen muchas uniones cruzadas ya que cada anillo fenólico tiene tres posiciones (dos orto y una para) que se pueden unir con el formaldehído por condensación. La Bakelita® puede moldearse a medida que se forma y endurece al solidificarse. No conduce la electricidad, es resistente al agua y los solventes, pero fácilmente mecanizable. Su permitividad dieléctrica relativa es de 0,65. El alto grado de entrecruzamiento de la estructura molecular de la baquelita le confiere la propiedad de ser un plástico termoestable: una vez que se enfría no puede volver a ablandarse. Esto lo diferencia de los polímeros termoplásticos, que pueden fundirse y moldearse varias veces, debido a que las cadenas pueden ser lineales o ramificadas pero no presentan entrecruzamiento. El brillo de la baquelita y el buen envejecimiento dan un aspecto inigualable a estas piezas que cada día se revalorizan por su escasez y singularidad, con bonitas pátinas en sus más diversos colores y tonalidades. Otro aspecto, único, de la Baquelita es su olor característico, debido al formaldehído, apreciable cuando la baquelita toma una cierta temperatura. HISTORIA Y ANTECEDENTES La Bakelita® o baquelita fue uno de los primeros plásticos comerciales (una resina de termofraguado) que se obtuvieron, llamada así en honor de su inventor, esta reacción fue descubierta en 1872 por L. Baekeland; un químico americano nacido en Bélgica. Baekeland ha sido un claro ejemplo de lo que se podría denominar un científico- empresario, pues utilizó los conocimientos científicos a su alcance para inventar un producto de gran utilidad social que le reporto grandes beneficios económicos. La baquelita es solamente un 2 ejemplo de la capacidad de Baekeland como empresario pues, antes de trabajar en el campo de los plásticos, ya había desarrollado un papel fotográfico denominado Velox que, por falta de la infraestructura necesaria para su comercialización, lo vendió a George Eastman de Kodak por un millón de dólares, dinero que le sirvió para financiar su trabajo sobre la baquelita. Fue producida por primera vez en 1907 y los métodos prácticos de moldeo de la baquelita se desarrollaron alrededor de 1909. Ha estado en uso comercial por más tiempo que cualquier otro polímero sintético. De la publicación realizada por Antonio Miravete: “Los nuevos materiales en la construcción”, es esencial entrecomillar el siguiente párrafo: “La bakelita fue el primer polímero completamente sintético, fabricado por primera vez en 1909. Recibió su nombre del de su inventor, el químico estadounidense Leo Baekeland. La baquelita es una resina de fenolformaldehído obtenido de la combinación del fenol (ácido fénico) y el gas formaldehído en presencia de un catalizador; si se permite a la reacción llegar a su término, se obtiene una sustancia bituminosa marrón oscura de escaso valor aparente. Pero Baekeland descubrió, al controlar la reacción y detenerla antes de su término, un material fluido y susceptible de ser vertido en moldes” IMPORTANCIA Y USOS Consecuentemente con sus propiedades la baquelita se convirtió en un material alternativo al vidrio, los metales y las maderas, pasando a constituir el principal material en elementos decorativos y funcionales. Se introdujo con rapidez en su aplicación a utensilios tradicionales de la cocina y el menaje, pasando en muy poco tiempo a elementos habituales del hogar. Las primeras aplicaciones de la baquelita fueron como aislante eléctrico y más tarde empezó a utilizarse en la construcción de accesorios plásticos para las industrias del automóvil y de la radio. Fue el precursor de gran cantidad de plásticos de tipo fenol- formaldehido. El propio Baekeland registró más de 400 patentes durante la investigación y desarrollo de la baquelita. Por sus propiedades como resina de termofraguado, se utiliza ampliamente en partes moldeadas, adhesivos, recubrimientos e incluso en otras aplicaciones resistentes a alta temperatura, como los conos de la nariz de los misiles. Se usa en la fabricación en grandes series de enchufes, tomas de corriente piezas de aparatos, zócalos, etc. La adición de colorantes apropiados permiten obtener efectos artísticos. 3 pero no produce nunca la fusión. PRODUCCIÓN La baquelita.... La reacción entre el ion fenóxido y el formaldehido es semejante a la reacción de Kolbe de carboxilación del fenol para dar ácido salicílico.El producto “C” resulta de la acción prolongada del calor o de polimerización del producto “B”. 2. el producto “B” es sólido a todas las temperaturas e insoluble en todos los disolventes corrientes. El cambio del estado “B” al “C” puede coincidir con un moldeado. Menos quebradizo que “A”.El producto “A” es sólido y tiene el aspecto de una resina amarillenta. 3.El producto “B” procede de la acción del calor sobre el “A” cuando éste se lleva más allá de la temperatura de fusión. Carcasa de teléfono realizada en Bakelita negra.Figura 1. El calor lo reblandece dándole la consistencia del caucho. permitiendo obtener formas muy diversas y realizar economías substanciales de mecanizado. Es el producto definitivo y el que posee las cualidades correctas. Su síntesis se realiza a partir de moléculas de fenol y formaldehído (Proceso de Baekeland). el fenol y el formaldehido. 4 . La baquelita presenta tres aspectos distintos que corresponden a tres etapas de su fabricación: 1. se obtuvo por condensación escalonada de fenol y formaldehido. se disuelve en el alcohol. Funde bajo la acción del calor. que fue el primer polímero completamente sintético. Reacción General Se sintetizo a partir de dos monómeros abundantes y baratos. en proporción 2 a 3. que pueden condensarse fácilmente en presencia de una base. 5 . El enlazamiento de moléculas continúa hasta formar una red extensa.Pasos: La reacción se lleva a cabo por etapas: el formaldehido se adiciona en primer término a las posiciones 2 y 4 de la molécula de fenol. Las moléculas sustituidas reaccionan a continuación con expulsión de agua. dando lugar a entrecruzamientos.material rígido insensible a los cambios de temperatura debido a su estructura entrecruzada.1 • La condensación del fenol con formaldehído es semejante a la condensación del fenol con acetona. • Obtenida mediante la reacción del fenol con algo más de un equivalente de formaldehído. mientras que las moléculas de fenol pierden dos o tres de sus átomos de hidrógeno. de forma que cada formaldehído conecta con dos fenoles. en orto y para. En exceso de fenol. perdiendo su oxígeno por sufrir dos condensaciones sucesivas. Este material puede moldearse de la manera adecuada y se somete posteriormente a temperaturas y presiones elevadas hasta que se convierte en una resina termoestable. y cada fenol con dos o tres formaldehídos.1 • La polimerización se lleva a cabo en varias etapas. Mecanismo de reacción.1 • En condiciones ácidas o básicas. 6 . El formaldehído sirve de puente entre moléculas de fenol. siendo uno de los intermedios una resina termoplástica – que se reblandece al calentarla.Condiciones de reacción. la misma reacción de condensación da lugar a polímeros lineales en los que cada fenol sólo conecta con dos formaldehídos. El papel o algodón es desenrollado de manera continua en la tina de impregnación de resina fenólica 2. DE R. Una vez impregnado para el estrato a través de un horno de precurado para que la resina empiece su proceso de curado.Producción industrial En ELECTROPARTES DE INDUCCION S. A continuación se describe cada uno de los procesos: PROCESO DE FABRICACION DE PLACAS 1. de acuerdo al tamaño de placa a fabricar. dejando el material en un estado semipegajoso conocido como etapa B. 3. El material entra a través de varios rodillos tensores en la tina de impregnación. 4. y tiene dos grandes divisiones. donde el material es sumergido en la resina especial para su grado de material. El material es dimensionado en hojas de un tamaño estándar. el proceso de fabricación de placas y el proceso de fabricación de tubos. 7 . Ambos procesos se realizan en ambientes controlados y con materia prima especial para aplicaciones eléctricas.L. El proceso de fabricación del Celoron y de la Baquelita es muy semejante. tienen el siguiente proceso de fabricación de baquelita en placa y en tubos. dejando el material en un estado semipegajoso conocido como etapa B. 6. los tubos se rectifican en su diámetro exterior para alcanzar las especificaciones de cada cliente. El material entra en una serie de rodillos tensores y posteriormente es rolado sobre un mandril de diámetro exterior igual al diámetro interior del tubo a fabricar. Una vez comprimido y termoestabilizado el material sale de prensa y entra al proceso de desorille. Las hojas son alimentadas en la prensa de compresión final. PROPIEDADES DE LA BAQUELITA 8 . PROCESO DE FABRICACION 1.5. 6. donde se apilaran un número de hojas relacionado a cada espesor a fabricar. DE TUBOS El papel o algodón es desenrollado de manera continua en la tina de impregnación de resina fenólica 2. 3. 7. El material entra a través de varios rodillos tensores en la tina de impregnación. se sacar el tubo y se manda al horno de curado final. 8. 7. donde el material es sumergido en la resina especial para su grado de material. En caso de ser requerido. El diámetro exterior es determinado el número de vueltas sobre el mandril de rolado. Terminado este paso. 4. El material es reembobinado con una intercapa para evitar que se pegue. Al alcanzar el diámetro exterior. el material está listo para ser embarcado. El rollo terminado es cargado en un desenrollador que alimenta la roladora de tubos. 5. 9. Una vez impregnado para el estrato a través de un horno de precurado para que la resina empiece su proceso de curado. 2 °F) .0 °C (68.0 °C (131.7 mmHg) a 55.46 noctanol/agua Temperatura de 715.6 %(V) Límites o límites explosivos inferior de explosividad: 1.Este polímero presenta una estructura del tipo reticular a base de uniones covalentes.319. las ventajas de los plásticos termoestables como la baquelita puede tener algunas aplicaciones dentro del campo de la ingeniería los cuales son: 1. Los usos más extendidos de la baquelita son: compuestos de uso general con cargas que aumentan su resistencia al impacto desde harinas de madera a celulosa con fibra de vidrio.0 °F) Solubilidad en agua 84 g/L a 20 °C (68 °F) Coeficiente de reparto log Pow: 1.109 congelación °F) . en el sector de automoción como adhesivos y en las arenas de moldeo de metales.lit.0 °F) autoinflamación Tensión superficial 38. los polímeros termoestables se obtienen en forma de dos resinas. relés telefónicos.0 °C (174.0 °F) 0.5 hPa (0. 4. con crgas del tipo mica para aumentar resistencias eléctrica y compuestos resistentes al calor de 150 a 180°C.0 °F) Información toxicológica: 9 . intervalo de ebullición Punto de inflamación 79. conectores.2 mN/m a 50. Propiedades físicas y toxicológicas de las materias primas y productos Fenol: Propiedades físicas y químicas básicas Aspecto Forma: sólido pH 6. A menudo. Punto inicial de ebullición e 182 °C (360 °F) .43 °C (104 .copa cerrada Inflamabilidad superior/inferior Límites superior de explosividad: 8. También se usa en dispositivos de instalación e interruptores eléctricos. estos agentes reforzantes pueden ser orgánicos o inorgánicos.0 °C (1. 6.7 %(V) Presión de vapor 6. endurecedores y plastificantes.0 °C (122. En general.lit. compuestos de aislamiento de electricidad.4 mmHg) a 20. 5. Una contiene los agentes de curado. 3. Tiene una alta estabilidad térmica Alta rigidez Alta estabilidad dimensional Resistencia a la termofluencia y deformación bajo carga Tiene un peso ligero Altas propiedades de aislamiento eléctrico y térmico.0 Punto de fusión/ punto de Punto/intervalo de fusión: 40 . la otra materiales de relleno y/o reforzantes. con entrelazamiento transversal de cadenas producido por el calor o por una combinación de calor y presión durante la reacción de polimerización. 2.3 hPa (4. 24 h Lesiones o irritación ocular graves: corrosivo Mutagenicidad en células germinales: Las pruebas in vitro demostraron efectos mutágenos Carcinogenicidad: Este producto es o contiene un componente no clasificable con respecto a su carcinogenia en humanos. ACGIH (American Conference of Governmental Industrial Hygienists.log Pow: 0. NTP (National Toxicology Program. basado en su clasificación por IARC (International Agency for Research on Cancer.04 . Carcinogenicidad: Carcinógeno regulado específicamente por OSHA Contiene metanol. No puede neutralizarse Baquelita: Propiedades físicas y químicas básicas 10 .copa cerrada Tasa de evaporación 1 Inflamabilidad superior/inferior o Límites superior de límites explosivos explosividad: 70 %(V) Límites inferior de explosividad: 7 %(V) Presión de vapor 53 hPa (40 mmHg) a 39 °C (102 °F) Densidad de vapor 1.(Aire = 1. Agencia para la Protección del Medio Ambiente) de los Estados Unidos. Programa Nacional de Toxicología) de los Estados Unidos o EPA (Environmental Protection Agency.04 . Formaldehido: Propiedades físicas y químicas básicas Aspecto Forma: líquido. Puede ser mortal o causa de ceguera en caso de ingestión. claro Color: incoloro Olor acre Punto inicial de ebullición e 100 °C (212 °F) intervalo de ebullición Punto de inflamación 64 °C (147 °F) .0) Información toxicológica: Sensibilización respiratoria o cutánea: Posibilidad de sensibilización en contacto con la piel.(Aire = 1. Agencia Internacional de Investigación sobre el Cáncer).Toxicidad aguda: Convulsiones o efectos en el umbral de colapso Corrosión o irritación cutáneas: Grave irritación de la piel .35 1. Conferencia de Higienistas Industriales Gubernamentales de los Estados Unidos).0) Densidad relativa 1.09 g/cm3 a 25 °C (77 °F) Solubilidad en agua totalmente soluble Coeficiente de reparto octanol/agua Densidad relativa del vapor n. tribológicas. el polietileno).Estado físico Apariencia y olor Concentración Peligros de fuego o explosión Densidad a 20 °C Solubilidad en agua y otros disolventes Resistencia a la flexión Resistencia a la tracción Resistencia a la compresión Solido en forma de polvo granular Polvo blanco sin olor 100% No existen 0. del oxígeno y del ozono. magnéticas. excelentes propiedades eléctricas de los laminados fenólicos.65-0. 11 . biodegradables Baquelita: La baquelita es una resina sintética a base de fenol y de formol. ayuda a las aplicaciones tanto la industria eléctrica como la industria química No conduce la electricidad. resistencia mecánica elevada. resistencia al ataque de los ácidos. El alto grado de entrecruzamiento de la estructura molecular de la baquelita le confiere la propiedad de ser un plástico termoestable: una vez que se enfría no puede volver a ablandarse. La baquelita en realidad es un copolímero. los copolímeros están constituidos. por dos monómeros diferentes.68 Insoluble 150 M Pa 120 M Pa 150 M Pa Información toxicológica: Toxicidad a corto plazo: no hay Toxicidad a largo plazo: no existe Efectos locales o sistémicos: irritación local leve Sensibilización alérgica: no debería producirse Propiedades del producto: ópticas. gran rigidez dieléctrica. A diferencia de los homopolímeros. es resistente al agua y los solventes. Reúne un conjunto de ventajas difíciles de encontrar en otras materias: Resistividad de 6 millones de MΩ/cm/cm2. al menos. que están formados por unidades monoméricas idénticas (por ejemplo. opacidad a los rayos X. 25%. es por eso que es importante conocer ampliamente acerca de ellos. ya que estos presentan mayores e inclusive mejores propiedades que los más antiguos. una vez que se enfría la baquelita no puede volver a ablandarse. en 1907. 2. Baquelita MOE Baquelita Judy Clarke Baquelita Shultz Conclusiones personales 1. madera. 10% del peso de los automóviles nuevos y de los muebles es de plástico.. así como 5% en los componentes eléctricos. vidrio y algunas fibras naturales) que permitió que muchos productos alcanzaran un consumo masivo. ‘Con el tiempo la sustitución ha disminuido. lo cual implica que todavía hay espacio para la sustitución. En los desarrollados se ha aprovechado al máximo el potencial del plástico y los polímeros. Desde que se creó la baquelita. Sin embargo en las últimas décadas se ha mantenido un mercado que demanda joyería fabricada con baquelita. Creo que sería adecuado poner atención en lo que nosotros como estudiantes podríamos hacer para seguir desarrollando lo que actualmente se conoce de la baquelita y de esta forma también poder ayudar al medio ambiente que es trabajo de todos. En los de menor desarrollo se siguen usando muchos materiales tradicionales.Respecto a lo que se ha venido investigando a lo largo de este proyecto. en el caso de los materiales usados en la construcción de casas y edificios. Se calcula que del total de la demanda de envase y embalaje. el trabajo de un ingeniero químico debe ser la optimización de los procesos que ya conocemos.. sus aplicaciones y las propiedades tanto físicas como químicas que presentan . no representa un alto grado de toxicidad. ya que como ingenieros químicos es importante saber la amplia variedad de materiales que tenemos a nuestra disposición y saber cuáles de ellos se acoplan 12 . nacional y/o internacional Desde el invento de la baquelita. es decir que puede moldearse apenas concluida su preparación. hasta ataúdes (que no tuvieron éxito en el mercado) y tanques de guerra.Debido al alto grado de entrecruzamiento de la estructura molecular de la baquelita le confiere la propiedad de ser un plástico termoestable. En otras palabras. se utilizó para fabricar una gran gama de artículos como tostadoras. Demanda regional. pero como sabemos. radios. sabemos que la baquelita tiene propiedades variadas que pueden ayudarnos en muchos ámbitos de la vida cotidiana y así mismo. sin embargo hay ciertas aplicaciones de las cuales no se le ha podido reemplazar debido a propiedades y características que solo presenta dichos polímeros. relojes. cartón. como la baquelita.Con el paso del tiempo los polímeros que se inventaron primero han sido dejados atrás por los nuevos polímeros sintetizados. cámaras fotográficas. se inició una sustitución de materiales (metales. su forma de sintetizarlos. ello ha impulsado el surgimiento de nuevos artistas que trabajan con este bello material. y al cuidado de nuestros recursos no renovables que se ven estrechamente enlazados con la fabricación de polímeros y de los plásticos más comerciales. dependiendo del desarrollo de los países. 40% se satisface con materiales de plástico. papel. esto debido a la nueva tendencia fashionista “Retro”. estatal. como por ejemplo: Baquelita Pantti. De esta forma ayudaríamos en el desarrollo potencial de nuestro país. The reduction in electrical conductivity of Bakelite material beyond 60 kGy is correlated to the conducting pathways and crosslinks in the polymer matrix. 4. Sahyadri College of Engineering & Management. samples of Bakelite RPC polymer detector materials were exposed to 8 MeV of electron beam with the irradiation dose from 20 kGy to100 kGy in steps of 20 kGy.ac.Los polímeros constituyen la mayor parte de las cosas que nos rodean.in:crang1@rediffmail. estamos en contacto con ellos todos los días e incluso nosotros mismos estamos compuestos casi en nuestra totalidad de estas. tan variadas macromoléculas.com Abstract. o-Ps lifetime and its intensity show chain scission at lower doses (20 kGy. Anexos Artículos científicos Electron beam induced microstructural changes and electrical conductivity in Bakelite polymer RPC detector material: A positron lifetime study K V Aneesh Kumar1. S Ningaraju1.Hoy en día los polímeros constituyen gran parte de nuestras vidas ya que absolutamente todo es polímero desde la ropa que nos ponemos hasta los envases para los alimentos.. The microstructural changes upon electron beam irradiation have been studied using Positron Annihilation Lifetime Spectroscopy (PALS) and Fourier Transform Infrared (FTIR) Spectroscopy.. Mysore-570006. India E-mail: cr@physics. Research Centre. una vez transformado el crudo en productos plásticos. 13 . The appropriate doses of electron beam irradiation of Bakelite material may reduce the leakage current and hence improves the performance of the detector. 3. la industria del plástico en nuestro país se ubica principalmente en el área metropolitana y en los estados de México. Positron lifetime parameters viz.uni-mysore.2 C 1 Department of Studies in Physics. H B Ravikumar1 and Ranganathaiah1. Nuevo León y Guanajuato. 40 kGy) followed by cross-linking beyond 40 kGy due to the radical reactions.. In order to explore the structural modification induced electrical conductivity. ya que podrían alcanzarse mayores ingresos por barril. University of Mysore. Nuestro país tiene una importante oportunidad de convertirse en proveedor. India.mejor a nuestras necesidades aplicando los conocimientos que hemos adquirido y de esa forma hacer nuestro trabajo eficiente y de manera apropiada. Adyar. L M Munirathnamma1. Mangalore – 575 007. 2 Govt. Jalisco. pero se puede ampliar a otras zonas. con ganancias superiores a las que deja la exportación de petróleo. lamentablemente estos polímeros no se degradan tan rápido como quisiéramos y también gracias a nuestras irresponsabilidades hemos contaminado el medio ambiente más de lo que creíamos y ahora debemos de tener una mayor conciencia para seguir aprovechando estos materiales para el bien del hombre y no como material contaminante y saber reciclar cada polímero nos haría menos contaminantes. Mangalore University. irradiation is treated as an effective tool for structural modification of polymers and plays a significant role in the material modifications. Introduction Resistive plate chambers (RPCs) [1] have found extensive applications in high energy and astrophysics experiments as the active detectors for muon detection. Matt finished NEMA LI-1989. authors carried out experimental investigations on the effects of electron beam irradiation on the microstructure of the polymer based Bakelite RPC detector material by one of the well established techniques viz. journal citation and DOI. 14 . 2. Grade XXX) of density 1. Figure 1. 2. India. which was developed on the basis of theoretical models originally proposed by Tao [7] for molecular liquids and later by Eldrup et al. The vital problem faced in such experiments is that Bakelite RPCs exhibit undesirable high leakage current compared to the glass RPCs [3]. Experimental 2.1. Any further distribution of this work must maintain attribution to the author(s) and the title of the work. Published under licence by IOP Publishing Ltd 1 Bakelite samples (P-120. India were procured from VECC Kolkata (INO-Lab).22 g/cm3. The RPCs made up of high resistive materials like Bakelite and glass are being used as the detectors for iron calorimeter (ICAL) to study atmospheric neutrinos in the proposed India based neutrino observatory (INO) project in India [2].1.175 cm were exposed to the electron beam of energy 8 MeV in air at Microtron Centre. The o-Ps lifetime (W3) is related to the free volume hole size by a simple relation given by Nakanishi et al. Bakelite has several advantages over glass detector material like low cost. Positron Annihilation Lifetime Spectroscopy (PALS) [4] and an attempt has been made to correlate the free volume change due to the electron beam irradiation on the electrical conductivity. there will be some modification in the microstructure of RPC material in the long run. [6]. As the RPC detectors are continuously exposed to charged particles like cosmic ray muons. These samples were used for PALS. However. Sample Preparation and Electron Beam Irradiation Content from this work may be used under the terms of theCreativeCommonsAttribution 3. In the present study.. The pairs of rectangular samples having dimensions 1 cm x 1 cm x 0. This problem has not been rectified in the past and it is interesting to find whether the high leakage current owes its origin to the microstructural changes of the Bakelite material upon exposure to charged radiation. Positron Annihilation Lifetime Measurements Positron annihilation lifetime spectra were recorded for the as received and electron beam irradiated Bakelite samples using positron lifetime spectrometer. for different doses up to 100 kGy in the interval of 20 kGy. [8]. The detailed description of PALS technique was given in our earlier paper [5].0 licence.Chemical structure of Bakelite. manufactured by Bakelite Hylam. The chemical structure of Bakelite is shown in figure 1. easy to handle in the fabrication of RPCs and as such it is very important to understand the origin of this leakage current. electrical conductivity and FTIR measurements. In recent years. India.2. 2. On the other hand. this may cause ionization or oxidation. The cleavage of bonds in Bakelite yield phenyl radicals.3. Results and Discussions 3. Japan FTIR Spectrometer with a resolution of 4 cm-1. As the radiation dose increases. Above 40 kGy. free 3. 11]. The variations of o-Ps intensity from 60 to 100 kGy is due to the structural modification of Bakelite polymer induced by the chain scission followed by the cross linking of the polymer chains. These arguments are adequately supported by FTIR results.5%) followed by a decline up to 100 kGy dose as seen from figure 3.90 Å3 to 69. Electrical Conductivity Measurements The electrical conductivity of the as received and electron beam irradiated Bakelite samples at different doses were measured using a standard set up with Keithley 2636A model with Source meter and computer program Lab Tracer 2. Since no changes in these wave numbers observed upon electron beam irradiation suggest that they do not influence structural modification of Bakelite. the o-Ps intensity (I3) decreases up to 60 kGy and a small increase at 80 kGy (only about 0. All such interactions may contribute to the inhibition of o-Ps formation. there is a remarkable decrease of o-Ps lifetime (τ3) about 71 ps and free volume size (Vf) by about 6 Å3 starting from 40 to 100 kGy irradiation dose in comparison to as received sample. which are the regions of low electron density exist mainly in the amorphous domains of Polymers.1. 15 . the absorption band at 3394 cm-1 corresponds to Phenol/OH in the as received sample gets shifted to 3420 cm-1 at 20 kGy and remains at this value for higher electron doses. and 2923 cm -1 correspond to the functional groups viz. 1647. This can be explained as follows. On the other hand. Upon irradiation.46 Å3 on electron beam irradiation up to 40 kGy and then decreases continuously to 58. Positronium (Ps) formation takes place preferentially at the free volume cavities. Also. Variation of o-Ps lifetime (τ3) and volume size (Vf ) as a function of electron dose. The absorbance bands at wave numbers 1457. the % of transmittance also increases which can be attributed to the chain scission resulting to the formation of more number of phenolic radicals. This is attributed to the cross-linking of Bakelite polymer chains due to the radicals formed by the scission of polymeric chains in the initial stages of irradiation. 3. this will hinder the polymer chain mobility [9]. there is a possibility of the interaction of free radicals with o-Ps. Figure 2.93 Å3 at 100 kGy (figure 2). C-H aliphatic bridge. C=C aromatic ring and stretching vibrations of CH2 alkane respectively [5. FTIR Studies The chemical modifications caused by electron beam irradiation on Bakelite are understood using FTIR scans shown in figure 4. FTIR Characterization The Fourier Transform Infrared (FTIR) Spectra for the as received and the electron beam irradiated Bakelite samples at different doses were recorded using KBr pellet method in the range of 4000-400 cm-1 with JASCO460 Plus. Figure 3.2. thereby inhibits the formation of positronium (Ps) [10].2. Positron Annihilation Lifetime Spectroscopy PALS results reveal that the free volume size increases from 64. the scission of polymer chains will increase the size of the free volume cavities and hence the o-Ps lifetime (τ3) [7]. these radicals undergo reactions with the electrons of the spur created during slowing down of positrons..4.0.The decrease in I3 may be due to inhibition of positronium (Ps) formation. Variation of o-Ps intensity (I3) as a function of electron dose. The absorbance band at 1053 cm-1 corresponding to single bond C-O stretching vibrations of -CH2OH. Variation of free volume size spectra of as received to 100 kGy electron beam (Vf) and electrical conductivity (σ) as a irradiated Bakelite samples in the interval of 20 kGy. [(a) to (f) represents FTIR Figure 5. Mysore. Govt of India for sanctioning the INO-DST Project to UOM. This is possibly due to the formation of hydrogen bonds by the radicals released during the scission of phenolic groups [11. 15]. At higher doses (above 60 kGy) cross linking is the predominant process and the formation of cross-links of the network hinders the movement of chains inside the polymer. conductivity increases and vice-versa. The increase in conductivity for the low electron doses may be due to the scission of hydrogen bonded phenolic groups lead to the formation of OH. Conclusions PALS results revealed that chain scission and cross linking are the predominant processes under electron beam irradiation on polymer based Bakelite RPC detector material. 16 .and H+ ions [12. This is also evident from the reduced free volume size (Vf) obtained from the PALS study.3. 4.and H+ radicals [5. 3. 17]. It was observed that the electrical conductivity increases on irradiation of electron beam dosage up to 40 kGy and then -8 -1 decreases to 1.08 x 10 (Ωm) at 100 kGy.] function of electron dose. FTIR spectroscopy indicates the scission of hydrogen bonded phenolic groups leading to the formation of OH. Electrical Conductivity Results Figure 5 shows the variation of free volume size and electrical conductivity as a function of electron dose and they exhibit behaviour upon electron beam irradiation that as the free volume increases. The electrical conductivity for 40 kGy electron irradiated sample is more compared to the as received sample indicative of increased mobility of a large number of OH. Acknowledgement The authors are grateful to DST.and H+ ions produced from the cleavage of hydrogen bonded phenolic groups. This indicate the formation of cross-links of Bakelite polymeric chains and reduces the formation of free radicals and reduce their mobility and hence reduction in electrical conductivity [16.This may further leads to the formation of OH.23x10-8 (Ωm)-1. FTIR Spectrum. Figure 4. The electrical conductivity (V) of the as received sample was 1.group shifted to 1036 cm-1 at 20 kGy and then increases to 1055 cm-1 and remains at 1055 cm-1 for higher dosages. The decrease in % of transmittance of O-H group at higher electron doses suggests the cross linking of polymeric chains of Bakelite. The increased cross-links at higher electron dose may possibly reduce the leakage current although it depends on the surface properties of the materials as well. 14]. These results agree well with the PALS results. These results indicate that the chemical changes due to the rearrangement of free radicals after the chain cleavage seems to contribute to the microstructural modifications in the Bakelite sample.and H+ radicals in the low dosage region. We propose that improvement in the performance of Bakelite RPC detector is possible with electron beam irradiation resulting in reduced leakage current. 13]. Huimingb W. Al momento de experimentar con la baquelita se puso en presencia de una una irradiación de electrones de hasta 40 kGy y el volumen neutro del polímero aumenta de 64. Bose S. Phys.46m. Xiao S and Liu H 2008 Thermochim.93 [7] Tao S J 1972 J. Hwang T S and Rafailovich M 2003 J. Chen Z. A 602 749-753 Nucl. Mohd Y A R and Ibrahim A T T 2010 J. Polym. 5 3704-08 Polym. 2001 Study and optimization of RPCs for high rate applications IEEE Nuclear Sci. La baquelita es un material RPC que sirve como detector y que tiene grandes aplicaciones en astrofísica ya que ayuda a detectar muones en el espacio y para estudiar los neutrinos atmosféricos como este detector esta hecho de baquelita y se encuentra en constante contacto con rayos cósmicos necesitan una modificación en su estructura. Lightbody D and Sherwood 1981 Chem.) Positron annihilation in fluids Singapore. Ravikumar H B and Ranganathaiah C 2013 J.Chem. Wang J Y and Boughton R I 2002 Macromolecules.Stab. J. Acta. 38 2433 [5] Aneeshkumar K V. Sci. Ooi C P and Boey F Y 2005 Biomaterials.35 9414-19 Resumen del artículo científico Electron beam induced microstructiral changes and electrical conductivity in bakelite polymer RPC detector material: A positron lifetime study. Appl. Crotty et al. Rongdiana H 2002 Eur. Ravindrachary V.26 1359-67 [13] Chen Y.References [1] Santonico R and Cardarelli R 1981 Nucl. Bhattacharya S . Chattopadhyay S. Thimmegowda M C and Ranganathaiah C 2002 Polymer. Meth. in: Sharma S C (Ed. 28 531-542 [15] Va'vra J 2003 Nuclear Symp. Esto se atribuye a la reticulación de cadenas de polímero de baquelita debido a los radicales formados por la escisión de las cadenas poliméricas en las etapas iniciales de la irradiación. Sci. Bhajantri R F. 4-10 November 2001) pp 1-17 [4] Shaojin J. Praveena S D. Instr. Dutta D and Pujari P K 2010 Degrad. Mohd N. [16] Siti A. Sci. Phys. Sathyanarayana P M.90 a 69. Xianfengb Z. Kim D. Appl. 56 5499-5510 [8] Eldrup M. Nat. Azizan A. Polym. Biernacka T and Skarzynski M 1983 J. es muy importante para entender el origen de esta corriente de fuga. Sin embargo.130 793-800 [6] Nakanishi H. Sci. Sect. World Scientific pp 292. Sharan M K and Viyogi Y P 2009 Instr. Este problema no se ha corregido en el pasado y es interesante saber si la alta corriente de fuga debe su origen a los cambios microestructurales del material de baquelita con la exposición a la radiación cargada. Poojary B. (USA. Symp. La irradiación se trata como una herramienta eficaz para la modificación estructural de los polímeros y juega un papel significativo en las modificaciones materiales. Yangmeib F. Phys. Res. Appl. 95 1083-91 [10] Shariff G. Zhicheng Z. Conf. Medical imaging Conf. el principal problema que enfrentan en estos experimentos es que baquelita RPC exhibe alta corriente de fuga no deseable en comparación con los RPC de vidrio. Hu X B. Wang S J and Jean Y C 1988 Microscopic surface tension studied by positron annihilation. esto va a dificultar la movilidad de la cadena de polímero. Meth.43 2819 [11] Lee Y. Kim H J. Polym. 2 190 [17] Liu H. 187 377-380 [2] Biswas S. 476 39-43 [14] Roczniak K. 63 51-58 [9] Ismayil. fácil de manejar en la fabricación de RPC y. 89 2589-96 [12] Loo J S C. la baquelita tiene varias ventajas sobre el material detector de vidrio como de bajo costo. Polym. Record 2003 IEEE. como tal. [3] Carlson P. Saha S. Las variaciones de intensidad o-Ps de 60 a 100 kGy se debe a la modificación estructural de la baquelita inducida por la escisión de la cadena seguido de la reticulación de las cadenas 17 . The carbon pick up in the liquid steel after reaction with varying blends of bakelite/coke for 30 minutes ranged between 0. The present study investigates a new route to utilize waste bakelite as a source of carbon in EAF steelmaking process. 10 Use of Waste Bakelite as a Raw Material Resource for Recarburization in Steelmaking Processes Somyote Kongkarat1)*. Sydney. Rita Khanna1). Since it cannot be remelted. El aumento de enlaces cruzados en dosis de electrones más alta puede reducir la corriente de fuga aunque depende de las propiedades superficiales de los materiales.au Bakelite is a thermoset plastic commonly found in electronic and automobile components.poliméricas.13 wt% to 0. Los resultados revelaron que la escisión de cadena y reticulación son los procesos predominantes bajo irradiación de haz de electrones sobre polímero a base de baquelita RPC como material de detector. Paul O’Kane2). Rooty Hill. Australia 2) Onesteel. Sydney.1002/srin. and Veena Sahajwalla1) 1) Centre for Sustainable Materials Research and Technology. CaCO 3 is generally found in the polymer as a filler material. e-mail: s. Australia * Corresponding author.kongkarat@unsw. School of Materials Science and Engineering. This paper reports the carbon dissolution behaviour of bakelite/ coke blends into liquid steel at 1550 8C. Estos argumentos se encuentran adecuadamente soportados por los resultados de FTIR. al término de la experimentación se propone la mejora en el rendimiento del detector de baquelita RPC es posible con irradiación de haz de electrones que resulta en la corriente de fuga reducida. the disposal of this material has become an environmental issue.17 18 . Pramod Koshy1).201100104 steel research int. 82 (2011) No. The University of New South Wales. La espectroscopia de FTIR indica la escisión de los grupos de hidrógeno de uniones fenólicas que conducen a la formación de OH. DOI: 10.edu.y H + que son radicales en la región de dosis baja. 2 and 3 respectively.withthenumbe rs rising further each year. Sahajwalla and Khanna [13] have reported that the rate of mass transfer of carbon atoms from graphite into molten iron was slower than the corresponding carbon dissociationrateatthesolid/liquidinterface.023 103 s1) > BK1 (0. Carbon dissolution.wt%. CaO present in coke ash is also known to desulphurize the liquid metal by reacting with carbon and sulphur.4. Ash oxides tend to form an interfacial layer between the molten iron and the carbonaceous materials. accepted on 8 April 2011 Introduction The global demand for plastics has grown significantly over the past few decades.005 103 s1) > coke (0. and is formed from the thermosetting phenol formaldehyde resin.045 103 s1) > BK3 (0.5%) were recycled. Through atomistic computer simulations. a small fraction of waste plastics (18. Steelmaking. The presence of CaS in the interfacial layer due to the CaO in the ash. the majority of these recycled plastics were thermoplastics such as polyethylene (PE) and polyethylene terephthalate (PET). coal and coke) directly into the melt or onto the top surface to cover the molten metal. more than 1. 11]. electronic components and kitchenware. Recycling Submitted on 30 March 2011. as shown by Eq. they also react with solute carbon in liquid metal leading to its subsequent depletion [6.5 million tonnes of plastics were consumed in 2009 [1]. Thermosets make up for only 0. The overall reduction of silica is shown by Eq. Keywords: Bakelite.Severalstudieshave focused 19 non graphitic materials into Fe and Fe-C alloys [4– 15].4% of plastics that are recycled1). Among these. . The dissolution rate (K) was also found to improve and the observed trend was BK2 (0. The depletion of solute carbon present in liquid metal can occur due to direct and indirect reduction of SiO2. The present work aims to investigate a novel route to utilize bakelite as a carbon and lime resource in steelmaking processes. Dissolution of carbon from coals and cokes is generally much slower than that from graphite and is significantly affected by the presence of sulphur [9. with the worldwide consumption approaching100milliontonnesperyear. The reaction products formed at the interface after 30 minutes of contact between liquid steel and bakelite/coke blends were observed to be a CaS-Al2O3 complex. and are generally landfilled or incinerated. thereby allowing for increased removal of the ash layer and greater carbon pick-up. and its presence was found to have a positive effect on modifying the properties of the coke. 7]. as shown by Eqs. or by injecting carbonaceous materials (graphite.Thepresen ceof sulphur is also known to retard carbon dissolution rates of graphite by decreasing the diffusivity of carbon into liquid iron [9–11]. This would decrease the volumes of waste polymers ending up in landfills and incinerators. particularly for recarburization. Carbon dissolution from coke has also been found to vary with the composition and contents of mineral oxides in the ash [7]. and thereby enhancing the carbon onthedissolutionof carbon from both graphitic and dissolution behaviour.003 103 s1).1 [22]. which gives it high hardness. both of which lead to environmental problems. rigidity and strength along with good thermal and electrical insulating properties. Previous Studies Dissolution of carbon into molten iron is a significant part of the carburizing process in ironmaking and steelmaking processes. Its chemical composition varies with the molar ratio between phenol and formaldehyde as well as the additives present in it. These studies were conducted primarily by immersing graphite in the form of a rod or disc into the molten metal. Carbon dissolutionfromgraphitegenerallyinvolvesthedissocia tion of carbon atoms from its crystal lattice site into the iron/ carboninterfaceandthetransferofcarbonatomsthroug hthe interfacial boundary layer into the bulk liquid iron [4–8]. 5]. Mass transfer in the melt was generally identified as a rate controlling mechanism [4. lowered melting temperature of the layer. and limited published research exists on the recycling of thermosets. The CaO is formed from the decomposition of CaCO3.1 wt%). This reaction produces CO and transfers CaS to the metal/carbon interface. these were generally higher than that observed from coke alone (0. In Australia. These polymers cannot be remelted to form a new product. CaOðsÞ þ S þ Csat ! CaSðsÞ þ COðgÞ (1) Silica is a major component of coke ash and reduced silicon can transfer into liquid metal [18]. It is used for parts of automobiles. Bakelite is a thermosetting amorphous polymer with a 3dimensional cross-linked network structure [2].[16–19]. CaCO3 is mostly added to commercially grade bakelite as a filler to improve its properties and to reduce the costs of production [3]. The plastic and coke were then blended in three different ratios (BK1. Melrose Park. Sydney.91 0.1wt% after 30minutes [18]. The present study investigates the carbon dissolution behaviour from bakelite/coke blends at 15508C using the sessile drop technique. 1. and is given in Table 1. These authors [15] concluded that the ash composition was a dominant factor that influenced the rate of carbon dissolution from cokes. BK2 and BK3). Experimental results will be discussedintermsoftherateofcarbondissolution.52g/min.017 CaCO3 30.18]. Ash (wt%) C H O S 53. Chemical composition of raw bakelite.03 SiO2 SO3 0.06 Figure 1.4 4. The carbon dissolution from graphite occurs at a very fast rate andtheextentofcarbontransferfromgraphiteintotheli quid metal at 15508C wasobserved to achieve saturationwithin a few minutes of reaction [20]. Cardiff NSW. The wide variation in the carbon picked up from coke by the two methods can be attributed to the type of coke. The material was fed at a rate of 0. 20 . the schematic of the DTF is shown elsewhere [24]. studied the carbon dissolution from different types of metallurgical cokes at 15508C using the carburizer cover method and reported that the carbon content in the liquid iron ranged from approximately 2wt% to over 5wt%. The blends were combusted in a drop tube furnace (DTF) to partly remove volatile matter at 12008C in an atmosphere of 20% O2 and 80% N2. On the other hand.Ashoxidesformedattheinterfaceac tas a physical barrier layer hindering the dissolution of carbon into the molteniron[18]. Bakelite and coke were crushed in a jaw crusher and sieved to a size of less than 1mm. of the blend composition on carbon and sulphur pick up by the metal as well as the formation of reaction products at the metal/carbon interface. variation intheexperimentaltechniqueandconditionsandtheco ntact area between carbon/iron in the case of the carburizer cover method.0 11.6 0. South Australia. Relative proportions of bakelite and coke present in the carbonaceous blends. Cham et al [15]. The chemical analysis of the raw bakelite was conducted by Amdel Industrial Services Division. Experimental Details Sample Preparation. The Table 1. Australia while the bakelite was obtained from STHAUST Plastic.SiO2 þ C ! SiOðgÞ þ COðgÞ (2) SiOðgÞ þ C ! Si þ COðgÞ (3) Chemical elements (wt%) SiO2 þ 2C ! SiðsÞ þ 2COðgÞ (4) The sessile drop technique has been used in the past to study the dissolution of carbon from graphitic and non graphitic materials into pure iron at 15508C [18– 21].theef fect The proximate and ash analyses of the carbonaceous samples after combustion in the DTF were conducted by Amdel Laboratory. and are given in Table 2 and Table 3 respectively. Australia. The metallurgical coke sample was provided by Onesteel.16. the carbon dissolution from coke occurs at a slow rate with the carbon content reaching approximately 0. Significantly low carbon pick up from the coke was explained in terms of the consumption of solute carbon by silica reduction and the formation of ash oxide layer at the interface[7. The proportions of bakelite and coke in the blends are shown in Fig. using a rolling mill. while the CaCO3 peak was noted to increase in intensity with increasing bakelite content.0 BK1 76.8 3.20 0.9 0. This technique has been previously used to study carbon transfer into liquid Coke BK1 BK2 BK3 SiO2 61.8 Fe2O3 2.8 47.9 26.07 0.XRD analysis of the coke and its blends with bakelite were conducted using a Philip X-pert Multipurpose Xray Diffraction (MPD). coals.1 BK3 68.5 28. and the results are shown inFig.3 2.27 0.5 28.5 Mn3O4 0. Carbonaceous samples Composition (wt%) Fixed Carbon Volatile Coke 79.5 23.80 18.9 52.6g of the samples Ash composition (wt%) 21 .2 BK2 73.77 MgO 0.8 3. as well as the wettability of molten iron with graphite.52 TiO2 1.29 0.27 iron. The crystallite height(Lc) ofthe carbonpeak (002)oftheblendswasnotfoundtochangeascomparedt oits parent coke.55 5.61 1.3 Al2O3 31.20 0.36 0.16 0.16 1.4 3.3 2.13 Table 2.9 2.04 0.18 SO3 0.3 Sulphur 0.3 Ash 17. 3. Chemical composition of the ash in the carbonaceous samples.59 0.35 Na2O 0.70 K2O 0.00 1.2 22.00 0.2 CaO 0.0 1.08 0.2 20. chars.25 0. Proximate analysis of the carbonaceous samples. Carbon dissolution experiments were carried out using the sessile drop technique in a horizontal tube furnace as shown in Fig.22 0.90 0.4 3.3 3.40 10. 2.55 0.33 0. cokes and refractory materials [18–21]. Approximately 1.29 0.0 2.30 P2O5 0. Table 3. Carbon Dissolution.4 56. Carbonaceous The carbonaceous blends were ground in a ring mill to obtain a fine powder which was sieved to a particle size<40mm. Once the assembly was pushed into the hot zone.99%) flowing at a rate of 1 L/min.5 KN using a hydraulic press.14cm2. A number of researchers [4– 15] have used a first order kinetic equation to describe the dissolution of carbon into liquid iron. The compacted substrate had a top surface area of 3. 4.5g of electrolytic pure iron (99. the interface. The images of liquid metal droplet and carbonaceous substrate inside the furnace obtained via a CCD camera are shown in Fig. This equation and its integrated form are shown in Eqs.Theexperimentswerecarriedoutunderanar gon atmosphere (Ar¼99.5 and 6.5. a CCD camera was used to monitor the metal droplet [18. and then slowly pushed into the hot zone where the temperature was 15508C. XRD patterns of the different carbonaceous blends compared to coke and raw bakelite.98% Fe) was put ontopofit.powder was put in a die and then compacted under a load of 7. The substrate was placed on a graphite tray and then 0. 20]. and this analysis was carried out using a Scanning Electron Microscope (SEM Hitachi S3400X) coupled with Energy dispersive X-ray Spectroscopy (EDS). Carbon and sulphur picked up by the metal droplets were measured using a carbon-sulphur analyser (LECO CS 230). 2. The bottom side of the metal droplet which was in contact with the carbon substrate was analyzed to investigate the reaction products formed at Figure 2. The sample holder wasfirstputin thecold zoneofthe furnace for approximately 5minutes to protect the system from thermal shock. respectively. 20 and 30minutes of the experiment time. The samples were quenched after 0. based on the carbon-concentration gradients. 8. 4. 15. 1. the melting of metal marked the beginning of the reaction time. ln sCtÞ dCt Ak ¼ ðCsCtÞ dt V ¼ K t (6) ðC 22 (5) . s1).5 to 4minutes) was significantly faster than that of BK1 and coke with the dissolution rate of 0. respectively. The ln((Cs–Ct)/(Cs– C0))-vs-time plot showed a slow rate of carbon dissolution (K¼0. and k is the first-order dissolution rate constant (m. Due to the experimental technique used in the present study.13wt% after 30minutes of contact. For metallurgical coke. The carbon pick-up results for coke are in agreement with previous carbon pickup studies carried out using the same technique [18].16wt% after 4minutes of contact. (7)) proposed by Chipman et al.ðCsC0Þ Carbon Dissolution from Coke and Bakelite/Coke Blends.023103 s1.5 to 4minutes) was also faster than that of BK1 and coke with the dissolution rate of 0.1wt% after 30minutes of contact.045103 s1. The carbon dissolution from BK2 in region I (from 0. can be measured from the negative slope of a ln((Cs– Ct)/(Cs–C0))-vstime plot.003103 s1). K¼Ak/V. There was little subsequent carbon transfer. there was no evidence whatsoever of any change in the rate of carbon dissolution could be observed. The carbon dissolution behaviour of BK3 in region II (from 4 to In these equations. could be indentified. However. The carbon saturation level (Cs) can be calculated from the empirical correlation (Eq.17wt% after 30minutes of reaction.98%) was used and thus. the initial carbon value (C0) was set to be zero. an electrolytic pure iron (99. the carbon concentration in liquid steel picked up quite slowly and reached a maximum of 0. Cs ¼ 1:34 þ ð2:54 103Þ T (7) Results and Discussion Experimental results are presented in the following sections along with a discussion of the factors influencing the carbon dissolution due to the blending of bakelite with coke. The ln((Cs– Ct)/(Cs–C0))-vstime plot showed a trend similar to coke with a slightly faster overall carbon dissolution rate (K¼0. an improvement in carbon dissolution behaviour was observed when bakelite/ coke blends were used. the carbon concentration in the melt picked up slowly and reached a maximum of 0. The variation in the carbon picked up by liquid steelas afunctionoftimeforbakelite/cokeblendscompared to that of coke are shown in Fig. The ln((Cs–Ct)/(Cs–C0))-vstime plot also showed two distinct regions. the carbon concentration in the liquid steel reached a maximum of 0. In the case of BK3. Cs and Ct represent the saturation solubility and carbon concentration (wt%) in the liquid iron Figure 3. However. at time t. the overall carbon dissolution rate constant.[26]: where T is in 8C. In region II (from 4 to 30minutes). Two distinct regions marked I and II. 23 . 5. faster carbon dissolution behaviour was observed with the carbon concentration in the melt reached a maximum of 0.005103 s1) can be observed. The carbon dissolution from blend BK3 in region I (from 0. Carbon and sulphur picked up by the liquid steel from bakelite/coke blends were measured and compared to that of metallurgical coke. The ln((Cs–Ct)/(Cs– C0))vs-time plot for coke and bakelite/coke blends are shown in Fig. the first-order dissolution rate constant (k) could not be determined. Schematic of the horizontal tube furnace. C0 is the initial carbonconcentrationintheliquidmetal(wt%). In the case of BK2. K is considered as the overall carbon dissolution rate constant (s1). 6.Inthisstu dy. and the measured overall dissolution rate constants are given in Table 4. The ln((Cs–Ct)/(Cs– C0))-vs-time plot showed a trend different from BK1 and coke. For blend BK1.AandVrepresentthe interfacial area ofcontact and the liquid iron bath volume. Figure 5.28wt% at level of carbon pick-up from coke and its blends with Figure 4.005103 s1. Variationinthecarbonpickupfrombakelite/cokeblendsbyliquidsteelat1550 8Ccomparedtocoke:(a)Datafromthefirst4minutesand 24 . The of 5.30minutes) was observed to keep on increasing bakelite was significantly below the saturation level slowly with the dissolution rate of 0. Images of liquid metal droplets while reacting with carbonaceous substrate at 1550 8C. Sulphur can transfer to the melt concurrently with the dissolution of carbon. Recently. the rate of carbon dissolution from metallurgical cokes into Fe-C melt at 15508C determined using the sessile drop technique was reported by Chametal.7103 s1.005 - BK2 0. Dissolution Rate Constants (K103s1) Carbonaceous Materials Region I Region II Coke 0. Sulphur Transfer from Coke and Bakelite/Coke Blends. the coke used is a poor carburizing material. Plots of ln((CsCt)/(CsC0))-vs-time for bakelite/coke blends compared to coke.045 0 BK3 0. [14] reported the overall carbon dissolution rate from a range of chars into Fe-C melt at 15508C to be 0.[28]tobe1. However.023 0.003 - BK1 0.1103 s1 and14. high ash oxide content in the coke is expected to significantly affect the carburization [7].whichcomprised32wt%oftheashinthe coke sample. especially the presence ofAl2O3. Khanna et al. Overall carbon dissolution rate constants of coke and bakelite/coke blends. The variation in the amount of sulphur transferred to liquid steel from coke and bakelite/ Figure 6.In the present study. Table 4. The overall rate of carbon dissolution into liquid metal depends on types and properties of carbonaceous materials.08-0. 15508C.64103 s1. The carbon dissolution from the coke occurred at a very slow rate.005 25 .(b) Data from entire reaction time. the longer reaction times may be required for the system to reach a state of thermodynamic equilibrium. rate of carbon dissolution was enhanced when bakelite/coke blends were used. the effect of volatiles on carbon dissolution was not considered in the present study.ForblendsBK1 andBK2. 7.05wt% within a few minutes.06wt% after 30minutes of reaction. The blending of bakelite with coke mainly resulted in a change in the chemical composition of the materials. Moreover. Sulphur transfer from the coke into liquid steel stabilized to 0. [7] reported that the influence of ash on the interactions 26 . it could be easily removed from the interface. With further increase in the bakelite content (for blend BK3) the overall sulphur pick-up was lower. This increases the contact area between the liquid metal and the solid carbon.coke blends is shown in Fig. It was found that the interface was predominantly covered by Al2O3 even after 4minutes of contact. SEM images of the steel/carbon interface as well as the EDS analysis ofthe interfacial region in the case of coke are shown in Fig. Thus. These authors concluded that the dissolution of coke was limited by the fusion temperature of ash. 17]. If the melting point of the ash layer is lower than the liquid metal temperature. and this influenced the relative proportions of the ash oxide layer formed at the metal/carbon interface. The volatile matter content in the bakelite/coke blends was observed to be quite similar (3wt%) to that of coke (see Table 2). the interface was also observed to be covered by Al2O3. 8. and thus enhances carbon dissolution.1wt% after 30minutes of contact. After 30minutes of reaction. The reduction of silica is one factor that can decrease the level of solute carbon in the liquid metal by converting silica into silicon in the melt [18. 19]. this ash layer was observed to grow with time.asimilar trendofsulphur transfer was observed. This correspondswiththeEDSspectrawhereaverysmallpeakof silica was detected even though it is the major component of the coke ash. Gudenau et al. Formation of Interfacial Reaction Products. Orsten and Oeters [17] studied the influence of additives like CaO on the carbon dissolution and found that the addition of CaO can reduce the ash melting temperature. The relative strength of the interfacial layer formed between the solid carbon and molten steel depends on its fusion temperature which in turn depends on the chemistry of the layer [7. as the coke used had high alumina content in the ash. The decreased sulphur pick-up in the case of blend BK3 compared to the other blends could be attributed to the greater desulphurization of the melt which could have occurredduetotheCaOcontentbeingthehighestamongthe blends. with the levelof sulphur picked up by the melt increasing from approximately 0.08wt% (after 2minutes of contact) to 0. Sulphur picked up stabilized to 0. Variation in the sulphur transfer from bakelite/coke blends into liquid steel at 1550 8C compared to coke. The thermal 27 . In the present study. The differences in the results of the two authors [7. These authors [7] also investigated the effect of additives and found that the addition of CaO. They suggested that phases that have lower fusion temperature than coke ash would aid the carburizing of iron by allowing the ash to be removed from the interface. Therefore.Figure 7. MgO and SiO2 decreased the dissolution of carbon. while CaCO3 is the key ash constituent in the case of bakelite. while Fe2O3 increased the dissolution. a major component of the coke ash is SiO2 and Al2O3. the blending of bakelite with coke results in the material having significant difference in ash chemistry compared to its parent coke. Al2O3. of industrial and special cokes with liquid iron was an important factor in controlling the coke dissolution. 17] may be attributed to the experimental conditions and materials. CaO and MgO varied significantly across the different blends compared to its parent coke. The following assumptions were made for the thermodynamic calculations: 1. which in turn would increase the relative fluidity oftheash layer. only the relative contents of SiO2.Figure 8. 2.CaOandMgOwereincludedastheash oxides in the calculation.Al2O3. athermodynamic software. CaCO3ðsÞ ! CaOðsÞ þ CO2ðgÞ (8) From Table 3. OnlySiO2. CaO would act as a fluxing agent and will reduce the ash melting temperature [17].8.23) The percentage of the different reaction products formed and the proportions of the solid / liquid components in these interfacial products were calculated using this software. which can occur during the combustion of the blend in the furnace. decomposition of CaCO3 is shown by Eq. FactSage 6. The high CaO in the bakelite/coke blend can decrease the melting temperature of the reaction products formed at the metal/carbon interface during reactions.0 [27]. This will result in the Al2O3 content decreasing proportionally (see Table 3). 28 . All the other ash components were low in content and did not show any significant variations in the different blends.Thechange inthe properties of the ash layer would produce differences in carbon and sulphur pick-up observed from bakelite/coke blends. Al2O3. thereby increasing the CaO content in the blend. was used. Fe2O3 was not included because it is assumed to be reduced under the experimental condition. SEM images of the metal/carbon interface for coke and the EDS spectra of the interfacial region. Toestimatetheproportionofthesolid/liquidcomponents of the interfacial products in the case of coke and bakelite/ coke blends at 15508C. 14 2.34 Al2O3 29 CaO CaS 0.07 BK3 52.9 27. CaO.0007 Mg2SiO4 0. In their study.6 8.1 0. it was found that over 80% of reaction products formed at the interface was liquid.77 BK1 71.0).54 BK2 59. Allthecomponentsoftheashareassumedtobedistributedhomogeneously throughout the sample.79 0.0).3.9 5. Sulphur was included in the calculations to assess itsinfluence on the reactions at the metal/carbon interface.0 are listed in Table 5. Relative constituents in the liquid component of the interfacial products for bakelite/coke blends and coke at 1550 8C (calculated using FactSage 6. 4. Relative percentages of solid / liquid components of the interfacial products for bakelite/coke blends and coke at 1550 8C (calculated using FactSage 6.9 18. Carbonaceous samples Solid % Liquid % Coke 40 60 BK1 23 77 BK2 7 93 BK3 3 97 Table 6.04 1.3 25. They also showed that the composition of ash oxides in the coke influences the viscosity of the interfacial products and hence the kinetics of reaction between coke and iron.[23] used FactSage to estimate the solid/liquid ratio of the reaction products formed at the interface at temperatures of 15008C and 15508C in order to investigate theinfluenceofthecontentandcompositionofashoxideson the carbon dissolution behaviour from cokes. Cham et al.45 3. the estimated proportions of the solid and liquid components of the interfacial products formed in the case of coke and bakelite/coke blends at 15508C as obtained from FactSage 6. In the present study. while the major Table 5.51 .4 10. The constituents of the liquid component were found to be SiO2. The estimated major constituents of the liquid and solid components are shown in Tables 6 and 7. These authors explained that the differences in the melting temperature and viscosity of the interfacial product resulted in the differences in the carbon dissolution behaviour of the different cokes. CaS and Mg2SiO4.5 0.13 0. Al2O3.7 20. Liquid Constituents (%) Carbonaceous samples SiO2 Coke 90. Si2O13 (Mullite) CaS Coke 99. As shown in Table 5.2 7. These could explain the greater carbon pick-up values in the case of bakelite/coke blends compared to coke alone. and this is in agreement with the results 30 .7 36.Table 7.4 BK1 92. With increasing bakelite content in the blend.3 BK3 0 100 constituent of the solid component was 3Al2O3.Si2O13 (mullite) and CaS. Solid Constituents (%) Carbonaceous samples 3Al2O3. while the contents of CaO and CaS increased expectedly. The liquid oxide layer which is readily removed from the interface can increase the metal/carbon contact area.6 0.andthepercentage of liquid component increased with increasing bakelite content in the blend. the interfacial reaction products in the case of bakelite/coke blends were moreliquidcomparedtothecaseofcoke. Relative constituents in the solid component of the interfacial products for bakelite/coke blends and coke at 1550 8C (calculated using FactSage 6. This provides the evidence that the CaO generated from bakelite has a beneficial effect in decreasing the ash fusion temperature of the materials. The estimated results show that the presence of CaO and CaS atthe interfacecan lower themelting temperature ofthe interfacial layer.8 BK2 63. the contents of SiO2 and Al2O3 in both the liquid and solid components of the interfacial layer were found to decrease.0). the interfaciallayerwillchange duetothedepositionofreaction products. the composition of the ash layer was found to change and become calcium enriched due to the formation of CaS complex. white regions representing mineral oxides were observed at the interface after 4minutes of contact and these were predominantly composed of CaS-Al2O3 mixture (Fig. 9 to 11). they will react with the mineral oxides in the interfacial layer. from literature [17]. The final composition and morphology of the interfacial layer is the result of the reactions which occur at the metal/carbon interface. the interfacial layer formed after 4 and 30minutes of reaction was also found to be composed of CaS-Al2O3 mixture as shown in Fig.CaO MgO. the presence of CaS at the interface was observed to increase proportionally with the decrease in Al2O3 (see Figs. the formationofinterfacial products isinfluencedbythekineticsof the reaction as the dissolution reactions continue.Theinterfacial reactions that take place include desulphurization of liquid iron and reduction of silica.Figure 9. A corresponding decrease in Al2O3 contents was seen from the interfacial images after 30minutes of reaction. The differences in the percentages of the solid/liquid components estimated using the FactSage 6. Once the carbon and sulphur atoms transfer across the interface into the liquid metal. 11. and form CaS at the interface as a reaction product. respectively. The formation of CaS and Al2O3 phases at the iron/carbon interface have been reported previously [19. the ash layer formed is assumed to be composed of SiO2 . The reduced Si is transferred into liquid iron. In the case of blend BK2 and BK3. and thus transfer reaction productsintothe interface. These results correspond to the thermodynamic results obtained using FactSage 6. However. Using the sessile drop technique.Al2O3 . carbon and sulphur atoms will dissociate from its host lattice into the interface and then dissolve into liquid iron. 21]. With ongoing dissolution.ForblendBK1.0 (Tables 6 and 7). SEM images of the metal/carbon interface for BK1 and the EDS spectra of points in the region. [19] investigated the iron/ natural graphite 31 .0 could explain the differences in carbon dissolution behaviour between the bakelite/coke blends and coke alone. 10 and Fig. The CaO generated from the bakelite can react with the dissolved carbon and sulphur atoms. This provides evidence that the greater desulphurization of the melt hadoccurred in the case of BK3 comparedtothecaseofBK2andBK1andthuscouldexplain the lower sulphur pick-up in the case of blend BK3 compared to BK2 and BK1. Once solid carbon is in contact with liquid iron. Wu et al. By increasing the bakelite content in the blends. SiO2 can also be reduced by the dissolved carbon through both direct and indirect reduction. The highest amount of CaS formed at the interface was seen in the case of blend BK3. In the case of bakelite/coke blends. 9). The reaction products formed at the metal/carbon interface in the case of bakelite containing blends were observed tobeacombination ofCaSandAl2O3. Ash oxides in the solid carbon will also form a layer at the interface. This suggests that there is a potential for using bakelite/coke blends as a replacement of coke as a recarburizing material. with the majority being SiO2 (72wt%). The presence of Al2O3 (which is a non wetting compound with high melting point >20008C) would hinder the liquid metalreactionwiththecokeinterface. They described the formation of the sulphide based complex as the effect of the desulphurization of the iron droplet. Therefore.Themetal droplets whichreactedwithblendsBK2 and BK3 were found to show faster dissolution rate compared to coke. the mechanisms related to the decrease in Al2O3 and the increase in CaO was not provided. no SiO2 was observed at the interface.Figure 10. the interface was found to be replaced by Fe/ Ca/S complex thereafter.[21] studied the iron/coke interface and also reported the formation of CaS complex at the interface. and as the reaction proceeded. interface and found that although natural graphite contained 8.8wt% ash.the presence of CaS and Al2O3 mixture at the interface in the case of bakelite/coke blends would aid the dissolution of carbonbyreducingthemeltingtemperatureoftheinterfacial products. These authors also reported that Al2O3 was observed at the interface initially. McCarthy et al. In the iron/coke system used in their study. the dissolution of carbon from coke was limited with the carbon pick-up after 30minutes of contact being approximately 0. This occurred due to the selective removal of silica at the interface initially and the later removal of CaO and its conversion into CaS [21]. and a similar trend of sulphur transfer compared to coke was seen in blend BK3.1wt%. However. 32 .Ontheotherhand. The low carbon dissolution was attributed to a combination of both poor dissolution rate and carbon consumption by reducible oxides in the coke ash. These authorsconcludedthattheproductionofsemifusedashatthe interface will reduce the interfacial area. the proportion of CaO increased and Al2O3 decreased. SEM images of the metal/carbon interface for BK2 and the EDS spectra of the points in the region. whereas it was 0.16 and 0. The measured carbon pick up value after 30minutes of reaction for metallurgical coke was approximately 0. The fastest carbon dissolution was observed in the case of BK2 for a first few minutes of reaction with the overall carbon dissolution rate constant (K) was 0.023103 s1. The addition of bakelite generally enhanced the carbon dissolution kinetics. The CaO arising from CaCO3 decomposition participates in desulphurization reactions to form CaSat the interface. 0. SEM images of the metal/carbon interface for BK3 and the EDS spectra of points in the region.Moreover.045103 s1. The major findings from this study are: 1.005103 s1. BK2 and BK3 respectively.003103 s1. itacts as afluxing agenttolowertheashfusiontemperatureoftheinterfacial 33 . Bakelite was partially blended with coke in a range ofproportions for carbon dissolution experiments.13.17wt% for blends BK1. 2. A slightly faster carbon dissolution rate was observed in the case of BK1 with the dissolution rate determined as 0. The presence of CaCO3 (present as a filler in the waste bakelite) was found to have a beneficial effect on modifying the chemical properties of the carbonaceous substrate which in turn affected the composition of the interfacial ash layer.10wt%. A similar trend was seen in the case of BK3 with the overall carbon dissolution rate constant was 0. Figure 11. The overall carbon dissolution rate for coke was 0. the carbon pick up was also seen to increase with increasing bakelite levels.Conclusions An in-depth investigation has been conducted on the dissolution of carbon from bakelite/coke blends into liquid steel at 15508C to examine the potential ofrecycling bakelite asasourceofcarbonandlimeforrecarburizationprocessesin steelmaking. W. Metall. V. pp. K. Mater. [5] M. 80 (2009). 471. Cootha Publishing House. pp. D. McGraw-Hill. Sharma: Steel Res. J. 3. 531. S. Eriksson. 44 (2004). Iron Steel Inst. R. http:// www.. V. [28] S. Zhao and V. Gudenau.andthiswouldleadtotheincreasedexposureof carbon to the liquid metal.. Sahajwalla: Metall. aumentando cada vez más. 25 (1998). S. P. M. R. Baldock: Metall. Olsson. G. Orsten and F. ASM. pp.. G. Int. 573. M. [17] S. G.. Trans. 34B (2003). Rahman. Dubikova: ISIJ Int. Jones: Ironmaking and Steelmaking. 1261. 2nd Ed. Accessed 24 Jan 2011. H. 64. 31B (2000). 243. Elliott: Metall. Sakurovs. la mayoría de 34 . pp. J. [7] H. Kosaka and S. Hack. [26] J.Theinterfaciallayercompositionhadbeenfoundto have a major influence on the dissolution of carbon. Chartrand. T. O’Kane. pp. Chipman. pp. Sun and M. Bale. [22] A. Book 3. W. D. Simento and V. [14] R. Inst. thereby improving the carbon dissolution behaviour. R. pp. Alfred. pp. Khanna: Metall. Trans B. Perzak: Trans. pp. Mulanza and D. L. 46 (2006). C. [3] S. T. O. C. 97. [12] S. Rosen: Fundamental Principles of PolymericMaterials. [20] L. Minowa: Trans. Acknowledgements We acknowledge the financial support received from the Australian Research Council for this project. pp. 1. [13] V. Cham. [10] C. Sahajwalla. Saha-Chaudhury: Metall.. 33. W. Sahajwalla.pacia. 44 (1952). B. P. [2] W. 24B (1993). Dubikova: ISIJ Int. G. Khanna. F. Tokuda and M. [9] Y. O. [4] R. Hart and N. Trans. Sahajwalla: Metall. Small. Wilson.. J. N. Wiblen and V. [19] C. Mellberg: Scand. 460. References [1] PACIA: 2009 National plastics Recycling Survey. R. Wu and V. 26 (1985). J. Pelton. 305. Wu. PA.. 426. [25] C. 19B (1988). pp. 36B (2005). Cham. for scientific information. 15. Gott. Biswas: Principles of Blast Furnace Ironmaking: Theory and Practice. 652. Sahajwalla: Metal. Masthieson and R. Cham. 1099.. G. 629. pp. pp. Mater. Sahajwalla and N. Trans. T.5 millones de toneladas de plásticos se consumieron en el año 2009 y solo un 18. pp. 392. Monaghan. B. Saha-Chaudhury. Mourao. Nightingale. Vol. 1215. V. B. Ohtani: Trans. pp. [6] M. K. B. Sakurovs. Oeters: Dissolution of carbon in liquid iron. Koump and T. Sahajwalla. Germany. 143. N. 47 (2007).6. ThermodynamiccalculationsusingFactSageshowedthatat 15508C the interfacial products were predominantly liquidwhenthebakelite/cokeblendswereusedcompared to coke. H. pp. 8 (1968). AIME. 1 st Ed. G. B. R. 353.. 719. B. 1860. pp. McCarthy. Shigeno. R. pp. Guernsky.org. Thomson. F. Fulton: Trans. L. [27] C. [16] M. P. J. Sun and M. Trans. Knights: Steel Res. Met... 31B (2000). V.au/Content/media-21. Khanna. Un estudio en Australia mostro que cerca de 1. Aachen. pp. pp. K. 375. V. Process Technology Proc. 6. 1517. J. Murthy and J. Khanna. Trans. Ericsson and P. Smith: Principle of Materials Science and Engineering. Wright and B. Sahajwalla.2009-1. [18] F. pp. McCarthy. H. Decterov. B. Sun. [21] F. J. V. A.. Chapman. [24] V. Wiley & Son. Simento: ISIJ Int. Nightingale: ISIJ Int. [23] S. T. R. R. Skidmore and D. Trans. Soc.. W. pp. 61 (1990). W. French: ISIJ Int. 1937. pp. A. D. 10 (1981). Sahajwalla. Liquid phases at the interface would easily be removed. USA. C. D. L. [8] N. N. J. M. Trans. Mater.5% fueron reciclados.layer. 2009. 1835. pp. [11] J. S. B. El uso de residuos de baquelita como recurso de Materias Primas para recarburación en procesos siderúrgicos RESUMEN En el mundo la demanda de plásticos ha ido creciendo enormemente siendo el consumo cerca de 100 millones de toneladas por año. McCarthy.aspx. 43 (2003). Sahajwalla: ISIJ Int. B. 1990. Sahajwalla: Metall. Australia. 31B (2000). W. J. 29B (1998).12. pp. Wu and V.0 GTT Technology. Thompson. Sakurovs. R. Petreson: FactSage. Sahajwalla and R. 1986. 45 (2005). 236 (1966). Khanna. pp. [15] S. 1981. 973. JOM. K. F. B. R. Melancon. 49 (2009). R. F. Japan. la captación de carbono también se observó a aumentar con el aumento de los niveles de baquelita. para recarburación. El CaO resultante de la descomposición de CaCO3 participa en las reacciones de desulfuración para formar CaS en la interfase. Se realizaron varias mezclas en diferentes proporciones de los componentes sólidos y líquidos de los productos interfaciales formados. En este artículo se investigó una nueva forma para utilizar baquelita como ejemplo. Para su producción comercial se añade CaCO3 a la baquelita como material de relleno para mejorar sus propiedades y para reducir los costes de producción. Se encontró que la presencia de CaCO3 tiene un efecto beneficioso sobre la modificación de las propiedades químicas del sustrato carbonoso y a su vez afectaba a la composición de la capa de interfacial. Se utiliza para piezas de automóviles. Después de 30 minutos de reacción de coque metalúrgico fue de aproximadamente 0. componentes electrónicos y utensilios de cocina. Una tendencia similar se observó en el caso de BK3 con la constante de velocidad total de la reacción de carbono era 0. rigidez y resistencia con propiedades aislantes térmicas y eléctricas. La disolución más rápida de carbono se observó en el caso de BK2 por unos primeros minutos de la reacción la constante de velocidad de disolución de carbono general (K) era 0. Esto disminuiría la cantidad de residuos de polímeros provocando menos contaminación. Baquelita es un polímero de alta dureza. y generalmente se depositan en vertederos o se eliminan por incineración.16% de BK2 y 0.023x10-3 S-1.17% para BK3 en peso para estas mezclas. Estos polímeros no pueden fundirse para formar un nuevo producto. ambos de los cuales conducen a los problemas ambientales. Las fases líquidas en la interfase se eliminaban fácilmente. La velocidad de disolución de carbono global de coque fue 0. Se realizó la investigación sobre la disolución de carbono de baquelita / coque fundido con acero líquido a 1550 °C para examinar el potencial de reciclaje de baquelita como fuente de carbono y cal para procesos de recarburación en la fabricación de acero. Se encontró que la composición de la capa interfacial tiene una gran influencia en la disolución de carbono.estos plásticos reciclados eran termoplásticos tales como polietileno (PE) y el tereftalato de polietileno (PET).003x10-3 s-1.13% de BK1.045x10-3 s-1. y esto daría lugar a la mayor exposición de 35 . La adición de baquelita mejora.10% en peso. mientras que fue de 0. en general la cinética de disolución de carbono. Los cálculos termodinámicos utilizando FactSage showedthat a 1550 °C nos mostró que los productos interfaciales eran predominantemente líquidos cuando se usaron las mezclas de baquelita / coque en comparación con coque. 0.005x10-3 s-1. Se obtuvo una velocidad de disolución de carbono ligeramente más rápido en el caso de BK1 con la velocidad de disolución determinado como 0. Facultad de Bellas Artes. BIBLIOGRAFÍA 1. España: Editorial Reverté. S.mex. Madrid. Miravete. 1995 9. PP: 25 8.carbono para el metal líquido. Octava edición. 787. mejorando así el comportamiento de disolución de carbono. España: Editorial reverté. Primera edición. Primera edición.G. RB. Weininger. García. Mimeur. EcuRed. España. México. PP. Consultado el 25 de septiembre de 2015 11. PP. (1995) Electromecánica de precisión. Universidad de Zaragoza.cu/index. Ubicado en http://www. Antonio “Los nuevos materiales en la construcción”. 1276. Primera edición. (2008) 10. (1995) Introducción a la química de polímeros. Séptima edición. PP: 246 7. 1020. (2004) Química Orgánica.php/Baquelita. Sergio “Referencias históricas y evolución de los plásticos” Universidad Politécnica de Valencia. Marin. 2. Baquelita. McMurry. J. Eduardo A. PP: 995 5. R. España.ecured. “Proceso de fabricación de celoron y baquelita” Electropartes de Inducción S de RL. Esto nos indica que es posible que exista un potencial para el uso de mezclas de baquelita / coque como un reemplazo de coque como un material de recarburación. L.1277. JW. Wade. McMurry. PP: 1217-1218 3. Ubicado http://celoronybaquelita. (2008) Química orgánica. Et al (1999) Química para el nuevo milenio. Hill. (2015).html Consultado el 25 de septiembre de 2015 36 en . Editorial Pearson Education. PP: 263-264 6. 2ª Edición. Editorial Pearson Education. Octava Edición. (1998) Química Orgánica. México: Editorial Cengage Learning. México: Editorial Pearson Prentice Hall. Editorial Antonio Miravete. Seymour. 1297 4. México: Editorial Reverté. (2012) Química Orgánica. J.tl/1277878_Proceso-de-Fabricacion. Quinta Edición. sigmaaldrich. Robert (1955) ELECTROMECANICA DE PRECISION. http://www. http://www.cu/Baquelita 22. Jesús (1989). 628.pdf 20. 37 .ecured.metal-service.com/MSDS/MSDS/DisplayMSDSPage.wordpress. Curso de fundamentos de Ciencia de Materiales. (2015) Baquelita: nostalgia por lo retro https://bigbenantiguedades. Morcillo. (1978) Química Orgánica (2a Edición). 14. pdf 21.sigmaaldrich. edit.upv. 13. Hochleitner. Allinger. P. Alvarez. r.a. http://www. 16. S.net/pdf/BAQUELITA. Norman L. madrid. gran guía de la naturaleza minerales y cristales. Hoja de seguridad http://www.com.pdf 24. Temas básicos de química (2ª edición). http://ri.es/materiales/Fcm/Fcm15/fcm15_6. p.bancomext.com%2Fcatalog%2Fproduct%2Fsial %2F252549%3Flang%3Des 19.com/nwebq/download/HDS/Polvo_de_moldeo_fenolico. http://www. Mimeur.pdf 23. Alhambra Universidad. 255 p.mx/rce/magazines/116/6/RCE6.sigmaaldrich.pdf 17.asiquim.mx/productos/baquelita_Micarta/Baquelita. Reverte 1984.uia.12.mx/gsdl/docdig/didactic/IngCienciasQuimicas/lqoa018.gob. Tecnoquim (2015) http://www. http://www.com/MSDS/MSDS/DisplayMSDSPage.com/tag/baquelita/ 25. Iraheta. Hoja de seguridad http://www. everest s.tecnoquim.edu.sigmaaldrich.bib.do?country= MX&language=es&productNumber=W322318&brand=ALDRICH&PageToG oToURL=http%3A%2F%2Fwww.html 15. y Hua.com%2Fcatalog%2Fproduct %2Faldrich%2Fw322318%3Flang%3Des 18. K.ues.pp26.do?country= MX&language=es&productNumber=252549&brand=SIAL&PageToGoToUR L=http%3A%2F%2Fwww.sv/2228/1/CARACTERIZACION_DE_LOS_POLIMEROS_U TILIZADOS_PARA_ENVASAR_AGUA_EN_PRESENTACION_DE_BOLSA _QUE_SE_COM.pdf 26. (2012) CARACTERIZACION DE LOS POLIMEROS UTILIZADOS PARA ENVASAR AGUA EN PRESENTACION DE BOLSA QUE SE COMERCIALIZAN EN EL INTERIOR Y LOS ALREDEDORES DE LA UNIVERSIDAD DE EL SALVADOR POR ESPECTROFOTOMETRIA INFRARROJA.(1997). http://revistas.