Struktol are used in rubber compounding. They provide coupling of non-black pigments to the polymer backbone allowing for: Improved abrasion, Higher compound modulus, Lower hystersis, Improved compression set, Improved rolling in tire tread compounds. Product name: Chemical composition: Features: Typical data: Product form: STRUKTOL SCA 98 Bis (3-triethoxysilylpropyl) tetrasulfide Improves reinforcing capabilities of fillers with silanol groups Improves abrasion Provides higher compound modulus Improves rolling in tread compounds Sulfur content: 21-23% 1.089 Yellow liquid STRUKTOL SCA 98CB Same as SCA 98 Same as SCA 98 Sulfur content: 10-12% 1.34 Black powder STRUKTOL SCA 98PL Same as SCA 98 Same as SCA 98 Sulfur content: 10-12% 1.00 Pale yellow pastille STRUKTOL SCA 98WT Same as SCA 98 Same as SCA 98 Sulfur content: 7.5-16% 1.43 Off white powder STRUKTOL SCA 984 3-Thiocyanatopropyltriethoxy silane Improves compound modulus Improves compression set Sulfur content: 12% Amber colored liquid Improves abrasion 1.03 STRUKTOL SCA 985 Bis (3-triethoxysilylpropyl) disulfide Improves reinforcing capabilities of fillers with silanol groups Sulfur content: 12-14% 1.04 Yellow liquid Improves abrasion Provides higher compound modulus Improves rolling in tread compounds 60a
Product name: Chemical composition: Features: Typical data: Product form: STRUKTOL SCA 985PL Bis (3-triethoxysilylpropyl) disulfide Same as SCA 985 Sulfur content: 6-7% 1.00 Pale orange pastille STRUKTOL SCA 989 3-Mercaptopropyltriethoxy Improves tensile strength MPTES content 95% Clear liquid silane Improves tear strength Improves abrasion 0.98 STRUKTOL SCA 989 WT 3-Mercaptopropyltriethoxy silane Same as SCA 989 SCA 989 content: 70% 1.20 Light gray powder STRUKTOL SCA 960 γ-glycidyloxypropyl trimethoxy silane Mainly used in glass reinforced epoxy resin, ABS, nylon and PBT SCA 960 content: >95.0% Improves tensile strength Density: 1.070+0.050 Improves tear strength Improves relative extensibility Clear liquid STRUKTOL SCA 972 Vinyl tri(2-methoxyethoxy) silane Improves the reinforcing capability of fillers with silanol groups in peroxide cured compounds Improves tensile strength SCA 972 content: >98.0% Clear liquid Density: 1.040+0.020 Improves tear strength Improves abrasion STRUKTOL SCA 974 γ-methacryloxypropyl trimethoxy silane Improves coupling of fillers with silanol groups, and fiberglass in the resin/ polymer matrix SCA 974 content: >97.0% Clear liquid Density: 1.040+0.020 STRUKTOL SCA 974WT Same as SCA 974 Same as SCA 974 SCA 974 content: 70.0+2.0 Clear liquid Density: 1.598+0.020 STRUKTOL SCA 1100 Aminopropyl triethoxy silane Improves the reinforcing properties of fillers containing hydroxyl groups Min. purity: 98.0% 0.941+0.01 Colorless liquid (07/07/04)AAC/rca 60b
STRUKTOL SCA 98 & SCA 985 An Overview STRUKTOL SCA 98 and SCA 985 are silane coupling agents for use in rubber compounding. When used in rubber compounding, they provide coupling of non-black pigments to the polymer backbone allowing for: Improved abrasion Higher compound modulus Lower hysteresis Improved compression set Improved rolling in tire tread compounds The theory for their effectiveness is that the silane portion of the molecule couples with OH groups on the silica and silicate surfaces in non-black pigments. The sulfur portion of the molecule is available for curing activity and can enter into the vulcanization mechanism. The SCA 98 is a tetra-sulfide silane while the SCA 985 is a di-sulfide silane. When the SCA 985 is used as a 1:1 replacement for the SCA 98, a reduction in the cured modulus and maximum tensile may be noticed. This can usually be regained by increasing the sulfur level in the final mix pass. THE REINFORCEMENT OF NON-BLACK FILLERS IS ENHANCED BY STRUKTOL SCA 98 & SCA 985 Suggested Dosage phr Levels per 100 phr filler Silica, ppt 3 13 Clay 0.3 1.0 Calcium Stearate 6 7 Magnesium Silicate (talc) 1 4 Fumed Silica 3-15 60c
MIXING AND DUMP TEMPERATURE Part or all of the non-black filler should be dispersed with the STRUKTOL SCA 98/SCA 985 in the first mixing stage. The remaining ingredients should be added after the silane coupling agent and the filler have been incorporated. Curatives should be added in the last mixing stage. SUGGESTED TYPICAL MIX SCHEDULE 0' Rubber ½' ½ to all non-black pigment STRUKTOL SCA 98/SCA 985 2½' Black, if present, oil, stearic acid, zinc oxide 3½' AO 2, AO 3 4½' Clean 5' Dump Because of the sulfur present in the STRUKTOL SCA 98/SCA 985, it is necessary to control the maximum mixing temperature. The following are recommended dump temperatures: Natural Rubber 150 C SBR 150-160 C NBR 140 C 60d
POLYMERS AND STRUKTOL SCA 98/SCA 985 EFFECTIVENESS ACM NDA IIR GOOD CM GOOD XNBR GOOD EPDM ECO FKM NDA HIIR HALOBUTYL GOOD CSM NATURAL RUBBER CR NBR BR IR SBR URETHANTE GOOD VAMAC GOOD Excellent - STRUKTOL SCA 98/SCA 985 favorably influences properties, producing significant improvements in physical properties and state of cure. Good - STRUKTOL SCA 98/SCA 985 has an effect on physical properties producing enhanced modulus and improved abrasion. NDA - No data available in actual experience with STRUKTOL SCA 98/SCA 985. 60e
AREAS OF RUBBER INDUSTRY WHERE STRUKTOL SCA 98/SCA 985 WOULD BE BENEFICIAL Footwear - abrasion - cutting and chunking - flex life improvement Rolls - abrasion - aging - processing - set reduction (better load bearing) - reduced water swell - lower hysteresis Mechanical Molded Goods - increased modulus - better heat aging - compression set reduction - dynamic property improvement - reduced swell to polar liquids - filler substitution (non-black for black) Hose - improved abrasion on cover - better heat aging - increased modulus - lower compression set - improved adhesion to reinforcing elements Solid Tires - improved abrasion - lower hysteresis - higher modulus - improved processing 60f
Tires - treads for abrasion, hot tear, improved rolling, - lower hystersis - carcass for adhesion and/or filler substitution - breaker (belt) stocks for adhesion Belts - Flat Belts - increased abrasion - improved reversion - reduced cost with clay substitution for black - improved cord adhesion - increased flex life and modulus Belts - V Belts - increased modulus - improved abrasion - longer flex life - improved adhesion to reinforcing elements 60g
Struktol Struktol silane coupling agents are for use in rubber compounds, particularly mineral-filled, and allow for: Lower compound viscosity Higher compound modulus Improved abrasion Lower hysteresis Improved compression set Improved rolling in tire tread compounds Improved dispersibility Faster incorporation Contact Struktol Company of America now for our brochure with CD. Phone: 800-327-8649 or 330-928-5188 E-mail: customerservice@struktol.com 60h