SILICONE RUBBER – PROPERTIES AND APPLICATIONSJohann Müller, Wacker Chemie AG, January 2011 CREATING TOMORROW'S SOLUTIONS AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller, Wacker- Chemie AG, January 2011 AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller, Wacker- Chemie AG, January 2011 NATURAL RAW MATERIALS: SALT AND SAND • Salt: • Natural NaCl production of chlorine via chloro-alkalielectrolysis • Sand: • Quartz is mainly Silicondioxide SiO2; production of silicon via reduction process Silicone Rubber – Properties and Applications Johann Müller, Wacker- Chemie AG, January 2011 RAW SILICON • Does not occur as pure element in nature • Has to be gained from quartz (SiO2) in an highly energy consuming process • Silicone of high purity (>99%) is needed SiO2 + C Si + CO2 Silicone Rubber – Properties and Applications Johann Müller. Wacker.Chemie AG. January 2011 . CHLORINE • Does not occur as pure element in nature • Has to be gained from salt (NaCl) in a highly energy consuming process (electricity) • Corrosive gas 2 NaCl + 2 H2O 2 NaOH + H2 + Cl2 Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. Wacker. January 2011 . CHLORINE. January 2011 Me4Si + HCl . Me2SiCl2 Me3SiCl Methanol MeCl . SILICONE AND ORGANICS: SILANES • Reaction of organic chlorides with silicone metal in the MüllerRochow-Process SiCl4 MeSiCl3 Cl2 Si Cu-cat.Chemie AG. Wacker.H2O Silicone Rubber – Properties and Applications Johann Müller. Wacker.9% purity Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. 98% Me2SiCl2 in >99.DISTILLATION OF SILANES yield approx. January 2011 . Chemie AG.AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 . Chemie AG.MAIN COMPONENT 1: POLYMERS • Silicon-Oxygen-Polymer: Polysiloxane (Q) Me Me2SiCl2 Me Si Cl Me Cl H2O . January 2011 Si O Me Si O Me .H2O Me Me Si Me Me Me3SiCl HO . Wacker.HCl HO Me Si Me OH Me .HCl Si Me instead of Me (Methyl) also Ph (Phenyl) or Vi (Vinyl) Silicone Rubber – Properties and Applications Johann Müller. January 2011 Si O Si O Si O Si O Si O Si O Si O Si O Si O .Chemie AG. Wacker.CHEMICAL STRUCTURE OF POLYMER CHAIN Si O Si O Si O MQ (Methylpolysiloxane) side groups = Methyl VMQ (Methyl-vinyl-polysiloxane) side groups = Methyl or Vinyl PVMQ (Methyl-phenyl-vinyl-polysiloxane) side groups = Methyl or Vinyl or Phenyl FVMQ („Fluorosilicone“) side groups = Methyl or Vinyl or fluorinated organic groups Silicone Rubber – Properties and Applications Johann Müller. MAIN COMPONENT 2: SILICA • skeleton based on oxygen and silicon. Wacker. January 2011 . similar to quartz • two main production processes: precipitated silica water SiCl4 fumed silica (HDK®) thermolysis Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. January 2011 .FUMED SILICA: HOCHDISPERSE KIESELSÄURE (HDK®) SiCl4 + 2 H2 + O2 SiO2 + 4 HCl burner SiCl4 + 2 H2 + O2 SiO2 SiO2SiO2 SiO2SiO 2 protoSiO2primary molecules particles particles aggregates agglomerates Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. Wacker. Chemie AG.MIXING OF SILICONE RUBBER Base Polymer Active Filler (HDK) Kneader Custom Compound (Roll Mill) Crosslinking System Additives Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 . PRODUCTION SCHEME Si-Wafer quartz sand silicon Silicon Silanes Siloxanes fumed silica HDK® oils silicon polymers crosslinker additives silicone rubber Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. Wacker. January 2011 . Chemie AG. Wacker. January 2011 .AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller. January 2011 . Wacker.Chemie AG.CLASSIFICATION OF SILICONE RUBBER BY CURING TEMPERATURE AND VISCOSITY silicon rubber high temperature curing silicone rubber HTV room temperature curing RTV solid silicone rubber HCR liquid silicone rubber LSR two component RTV-2 one component RTV-1 peroxide cure addition cure Pt-catalyzed addition cure Pt-catalyzed addition cure Pt-catalyzed condensation cure Sn-catalyzed condensation cure Sn-catalyzed Silicone Rubber – Properties and Applications Johann Müller. LIQUID SILICONE RUBBER: PROCESSING (1) (2) (3) (4) (5) Silicone Rubber – Properties and Applications Johann Müller. January 2011 pumps color dosage static mixer dosing unit mould .Chemie AG. Wacker. Wacker.LIQUID SILICONE RUBBER: COMPONENTS • Polymer + filler • Crosslinker • Catalyst • Inhibitor A-Component • Polymer + filler • Pt-catalyst B-Component • Polymer + filler • Crosslinker • Inhibitor Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. January 2011 . Chemie AG.LIQUID SILICONE RUBBER: KINETICS OF PT-CATALYZED CROSSLINKING REACTION torque 170 °C Pt-catalyzed reaction Peroxid time Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 . Chemie AG.ELASTOSIL® LR: PREPARED FOR VARIOUS APPLICATION AREAS highly transparent electrically conductive heat resistant standard tear resistant fast curing non post cure flame retardant media resistant self adhesive self lubricating Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 . pot life) • Catalyst: platinum compound • Reactants are: VMQ-polymers with terminal vinyl groups (polymer) VMQ-polymers with at least 3 Si-H-groups (crosslinker) Pt-catalyst Silicone Rubber – Properties and Applications Johann Müller. January 2011 . Wacker.LIQUID SILICONE RUBBER: SUMMARY • 2 component system: • Crosslinking via hydrosilylation of vinyl groups of the VMQ-polymer • Curing temperatures above 100 °C • No vulcanization at 25 °C (room temperature .Chemie AG. Chemie AG. January 2011 . Wacker.SOLID SILICONE RUBBER (HCR) DELIVERY FORMS Silicone Rubber – Properties and Applications Johann Müller. hot air or IRchannel (pressureless) • Press vulcanization: crosslinking in presses with heating (under pressure) • Injection molding Silicone Rubber – Properties and Applications Johann Müller. January 2011 .SOLID SILICONE RUBBER: PROCESSING • Mixing of additives or mixing of 2-K products on the open mill: Important requirements: • Mills have to be cooled (not too cold in order to avoid condensation of H2O on the surface) • Pt-catalyzed compounds have to be stored under cooled conditions (< 25 °C) • Surface of mill has to be polished • Crosslinking is done depending on production process: • Extrusion: crosslinking via salt bath. steam.Chemie AG. Wacker. SOLID SILICONE RUBBER: Pt-CURING GRADES ELASTOSIL® R plus • Polymer + filler 1K • Crosslinker • Catalyst • Inhibitor ELASTOSIL® R plus • Polymer + filler 2K • Crosslinker • Inhibitor Silicone Rubber – Properties and Applications Johann Müller. January 2011 Catalyst . Wacker.Pt1 respectively Pt2 .Chemie AG. Wacker.Chemie AG. January 2011 .SOLID SILICONE RUBBER: Pt-CATALYZED GRADES ELASTOSIL® R plus • Curing catalysed via platinum compounds • 2K-grades and 1K-grades • Processed at 150-170 °C by injection moulding compression molding or extrusion • Highest mechanical strength within the silicone elastomer family Silicone Rubber – Properties and Applications Johann Müller. 190 °C CH3 CH3 H3C C O O CH3 CH3 O O CH3 C CH3 CH3 C CH2 CH2 C CH3 170 .190 °C CH3 CH3 Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 .Chemie AG.SOLID SILICONE RUBBER: PEROXIDE CROSSLINKING Extrusion: Cl O Cl C O O O C Cl Cl crosslinking temperature > 100 °C Molding: CH3 CH3 O C O C CH3 165 . January 2011 . Wacker.Chemie AG.LIQUID SILICONE RUBBER: KINETICS OF PT-CATALYZED CROSSLINKING REACTION torque 170 °C platinum cure Peroxid time Silicone Rubber – Properties and Applications Johann Müller. Chemie AG. Wacker. January 2011 .SOLID SILICONE RUBBER: KINETICS OF CROSSLINKING torque 170 °C platinum cure peroxide cure time Silicone Rubber – Properties and Applications Johann Müller. January 2011 .SOLID SILICONE RUBBER: PEROXIDE CURING GRADES ELASTOSIL® R • Curing through organic radicals by peroxide (E.Chemie AG. C1. Wacker. C6) decomposition • Processed at 160-190 °C by compression molding or injection moulding or extrusion • Very high mechanical strength Silicone Rubber – Properties and Applications Johann Müller. January 2011 .Chemie AG.POSTCURING OF SILICONE RUBBER ARTICLES • Recommendations for thermal post-treatment of vulcanisates • Use of enough fresh air: 120 l per kg and min • Duration: 4 hours at 200°C (> 4 mm: + 2h/mm) • Loose packing of articles • Do not mix peroxide and Pt-cured articles • Reasons for postcuring: • Minimization of peroxide decomposition products (not in case of Pt-cure) • Decomposition of excess crosslinker components • Optimization of physical properties • Minimization of volatiles Silicone Rubber – Properties and Applications Johann Müller. Wacker. high vulcanization speed) • Fully automized process • Molds with up to 128 cavities • Possibility of producing articles with complex geometry • 2-component-injection molding • No reworking (no flash etc. January 2011 .SOLID OR LIQUID SILICONE RUBBER? liquid silicone Advantage: • Short cycle time (low viscosity.) solid silicone Advantage: • Better physical properties of products • Higher flexibility in processing • Molding • Extrusion • Calendaring • Assembly Silicone Rubber – Properties and Applications Johann Müller. Wacker.Chemie AG. etc. medical) • High transparency • Dry surface • Better physical properties (tear resistance. Wacker. elasticity.) Silicone Rubber – Properties and Applications Johann Müller. January 2011 . KTW.Chemie AG. FDA.PEROXIDE OR Pt-CATALYZED CROSSLINKING? Pt-(addition-)cure Advantage: • Fast crosslinking peroxide cure Advantage: • Not sensible towards catalyst poisons • „Unlimited“ storage time for compounds • No by-products from crosslinker (BfR. AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller.Chemie AG. Wacker. January 2011 . PROPERTIES OF SILICONE RUBBER Silicone Rubber – Properties and Applications Johann Müller. Wacker.Chemie AG. January 2011 . January Wacker Academy 2011 29. Slide 49 . fully saturated backbone • High bonding energy: Si-O 451 kJ/mol (for comparison C-C 352 kJ/mol) • Low surface energy.11.PROPERTIES OF SILICONE RUBBER DERIVATION FROM STRUCTURE OF POLYMER • Inorganic.2010. organic side groups shield backbone • High flexibility of chains n m Excellent high temperature resistance and low temperature flexibility High resistance towards chemicals and environmental influences Water and dirt repellant surface Silicone Rubber – A Properties General Introduction and Applications Johann Dr. AG. Jürgen Müller. WackerWacker Chemie Chemie AG. Ismeier. Chemie AG. O. Wacker. in case of combustion only non-toxic combustion products Silicone Rubber – Properties and Applications Johann Müller. January 2011 . C and H n m High transparency Good mechanics due to effective polymer-filler-interaction Good flame retardant properties.PROPERTIES OF SILICONE RUBBER DERIVATION FROM STRUCTURE OF POLYMER AND FILLER • High similarity of structure of polymer and filler • Polymer and filler contain only Si. Wacker.35 g/cm³ 3-90 Shore A 5-11 N/mm² 100-900 % 5-50 N/mm 10-25 % Rebound resilience 20-70 % Silicone Rubber – Properties and Applications Johann Müller.TYPICAL MECHANICAL PROPERTIES OF SILICONE RUBBER Specific gravity Hardness Tensile strength at break Elongation at break Tear resistance (ASTM D 624) Compression set (175°C. January 2011 . 22 h) 1.05-1.Chemie AG. easily pigmentable • Excellent compression set • Neutral taste and smell (a lot of grades comply with regulations of BfR and FDA) • Easy processing Silicone Rubber – Properties and Applications Johann Müller.PROPERTIES OF SILICONE RUBBER • Broad range of usage temperature from -50 °C up to +250 °C (special grades -110 °C up to +300 °C) • Almost no change of properties between 0 °C and 150 °C • Electrically isolating to semi-conductive • Resistant to radiation. ageing and weathering • Transparent.Chemie AG. Wacker. January 2011 . Chemie AG. January 2011 . Wacker.AGENDA • Raw materials for silicone rubber • Production of silicone rubber • Liquid and solid silicone rubber • processing • crosslinking • Properties of silicone rubber • Silicone rubber in comparison to other elastomers Silicone Rubber – Properties and Applications Johann Müller. January 2011 . Wacker.Chemie AG.SILICON RUBBER IN THE WORLD OF ELASTOMERS Silicone Rubber – Properties and Applications Johann Müller. 10 % turnov. FMVQ • (E)CO • EVM. NBR. AEM. Wacker. BR. January 2011 . (X)IIR 17 % volume 30 % turnover General Purpose Elastomers: NR. ACM • CSM volume Silicone Rubber – Properties and Applications Johann Müller.RUBBER CLASSIFICATION price 1 % vol. PMVQ. Speciality Elastomers: CR.Chemie AG. EP(D)M. SBR 82 % volume 60 % turnover High Performance Elastomers • FKM • HNBR • MVQ. AND OIL-RESISTANCE (ACCORDING TO ASTM-D 2000/SAE J 200) 250 FPM FKM 200 heat resistance* (°C) 80% VA FVMQ HT-ACM MVQ VMQ 150 44% ACN HNBR 34% ACN HNBR 48% ACN ACM ACM AEM EVM 40% VA EPDM EPDM NBR NBR CO/ECO 18% ACN CM/CSM IIR 100 CR SBR SBR BR BR NR NR 50 10 20 30 * temperature at which after 1000 hours.Chemie AG. Wacker. January 2011 . 50 % of initial elongation at break are retained 40 80 100 120 140 60 maximum swelling in oil IRM 903 (%) no requirements Silicone Rubber – Properties and Applications Johann Müller.HEAT. 50 % of initial elongation at break are retained heat resistance* (°C) Silicone Rubber – Properties and Applications Johann Müller.Chemie AG.LOW TEMPERATURE FLEXIBILITY AND HEAT RESISTANCE 0 low temperature flexibility TR (°C) according to DIN 53520 ACM ACM EVM CM/CSM HNBR HNBR AEM NBR ECO CO/ECO IIR EPDM FVMQ FKM -20 CR CR -40 NR SBR SBR -60 BR BR VMQ -80 60 80 100 120 140 160 180 200 220 240 260 * temperature at which after 1000 hours. Wacker. January 2011 . SUMMARY OF PHYSICAL PROPERTIES NR BR SBR EPDM IIR CR NBR CSM/CM ACM EVM AEM ECO/CO VMQ HNBR FKM FVMQ heat resistance low temperature flexibility oil resistance fuel resistance ozone-/weathering resistance mechanical properties (23 °C) mechanical properties (100 °C) tear resistance abrasion resistance low temperature C. January 2011 .Chemie AG. Wacker.S. (-20 °C) high temperature C. (120 °C) gas impermeability processing prics Rating (all properties except price) excellent fair weak price low medium high Silicone Rubber – Properties and Applications Johann Müller.S. January 2011 .Chemie AG.SILICONE RUBBER APPLICATIONS Sports and Fashion Others Electrical Energy T&D. Cable 10% 10% Automotive 20% 20% Electronics Photonics Solar Silicone Elastomer 25% 25% Market 2009 1.8 BN EUR* 15% 15% 10% 10% 20% 20% Household Machinery Sanitary Medical and Health Care Baby Care * Source: WACKER estimates Silicone Rubber – Properties and Applications Johann Müller. Wacker. January 2011 .Chemie AG. Wacker.THANK YOU FOR YOUR ATTENTION! Silicone Rubber – Properties and Applications Johann Müller.
Report "40. Silicone Rubbers- Properties and applications- Hans mueller.ppt"