Heretofore, carbon black has been used as a reinforcing filler for rubber because carbon black provides higher reinforcement and more excellent abrasion resistance than other fillers. Recently, because of social requirements to save energy and to save resources, particularly to cut down fuel consumption of automobiles, a decrease in the heat buildup of rubber compositions is also required.
For decreasing the heat buildup of rubber compositions by using carbon black, use of a small amount of carbon black or carbon black having a large particle size is considered. It is, however, well known that, in both methods, decreasing heat buildup is in a contradictory relation with improving reinforcement and abrasion resistance of a rubber composition.
On the other hand, silica is known as a filler which provides decreased heat buildup of a rubber composition. However, silica particles tend to cohere together due to hydrogen bonding of silanol groups which are functional groups on the surfaces of the silica particles. For improving the dispersion of silica particles into rubber, the mixing time must be increased. When dispersion of silica particles into rubber is insufficient, a problem arises in that processability in processes such as extrusion and the like deteriorates due to the increase in the Mooney viscosity.
Moreover, the surfaces of the silica particles are acidic. Therefore, there are problems in that basic substances used as vulcanization accelerators are absorbed such that vulcanization is not carried out sufficiently, and a sufficient modulus of elasticity is not obtained.
In order to solve these problems, we developed various types of silane coupling agents.
This is a bifunctional polysulfidic organosilane for the rubber industry defined chemically as Bis(3-triethoxysilylpropyl)tetrasulfide. It is used to improve the reinforcing capability of fillers with silanol group on their surface (e.g., silicas, silicates, clay, etc.), and also as an integral part of curing systems to improve crosslinking network properties.
Technical Properties
Empirical Formula
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C18H42O6S4Si2
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Molecular Weight
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539
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Boiling Point
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Decomposition above 250°C [760mmHg]
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Flash Point
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Min.100 °C
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Pour Point
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App.-80°C
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Color and Appearance
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Yellowish clear liquid
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Density [25°C]
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1.09
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Volatiles components
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Max 4.0%
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Average chain length
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3.75 +/- 0.15
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Total Sulfur (standard value)
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22.7 +/- 0.8 %
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Soluble in
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Primary alcohols, ketones, benzene, toluene, chlorinated hydtocarbons, acetonitrile, dimethylformaminde, dimethysulfoxide
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Insoluble in
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Water
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Applications
· Coupling Agent
With as little as 0.5 to 1.0 phr with clay fillers and 1.0 to 4.0 phr for silica pigments, PC2000 couples the non-black pigment and elastomers resulting in increases in modulus and increase in abrasion resistance.
· Cure Equilibrium
The Bis(3-triethoxysilylpropyl)tetrasulfide has four sulfur atoms positioned in the center. At cure temperatures, these participate with sulfur in producing polysulfidic crosslinks. It replaces crosslinks broken during cure, resulting in reversion resistant, and with proper compounding, reversion free compounds. This is known as equilibrium cure. The dynamic flex characteristics, E.G., heat generation and crack growth, are dramatically improved.
· Curing Agent
Removing all sulfur from the compound for NR, SBR, NBR and replacing it with the Bis(3-triethoxysilylpropyl)tetrasulfide and certain thiuram accelerators, produces compounds with excellent heat aging characteristics in addition to the coupling effects. It is a silane coupling agent that has crosslinking and accelerator activity in rubber compounds. Area of rubber industry where them would be beneficial
· Footwear
Abrasion resistance | Cutting and chunking resistance | Flex life improvement
· Rolls
Abrasion resistance | Aging resistance | 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 | Possibly better adhesion
· Tires
Treads for abrasion, hot tear | Carcass for adhesion and/or filler substitution | Breaker (belt) stocks for adhesion
· Belts Flat Belts
Increased abrasion | Improved reversion resistance | Reduced cost with clay substitution for black | Improved cord adhesion | Increased flex life and modulus
· V Belts
Increased modulus | Improved abrasion | Longer flex life | Improved adhesion to reinforcing elemen
Organosilanes assure permanent bonds between two material systems that are otherwise incompatible. Pre-mixed blends of organosilanes and carbon black offer manufacturers free-flowing powders to complement their choice of organosilane products. Chinese producer and exporter of organosilanes and glyoxal. Supplies custom and fine organic chemicals and organosilanes, including pharmaceutical intermediates.
Organosilanes assure permanent bonds between two material systems that are otherwise incompatible. Pre-mixed blends of organosilanes and carbon black offer manufacturers free-flowing powders to complement their choice of organosilane products. Chinese producer and exporter of organosilanes and glyoxal. Supplies custom and fine organic chemicals and organosilanes, including pharmaceutical intermediates.
Manufacturer and exporter of rubber stoppers for pharmaceuticals industries. Chinese manufacturer of rubber sheeting,rubber extrusion and molded rubber products. Provides a product catalog and industry news. Natural rubber producer and exporter of both raw materials for industrial use and finished products including tires and rubber gloves.
