Butyl reclaimed rubber is a recycled rubber that is processed from waste butyl inner tube to replace butyl rubber and reduce the cost of raw materials. Some of the butyl reclaimed rubber is used to produce various rubber sealing products; There are many factors in the sealing effect of the products. The compression resistance and the heat resistance of the rubber are important factors. Xiaobian once discussed the compression set and heat resistance of the rubber sealing products separately, then the butyl reclaimed rubber. What is the heat resistance of the sealed product under compression?
In general, the heat resistance of the butyl reclaimed rubber sealing article during compression deformation is much lower than that when it is not deformed, so that the heat aging resistance under compression of the butyl reclaimed rubber sealing article used at a relatively high temperature for a long time is improved. Extending the service life of butyl sealing products is of great significance. Rubber product manufacturers can improve the heat resistance of butyl sealing products under compression by adjusting the vulcanization system, reinforcing filling system and softening plasticizing system.
1. Vulcanization system
1 Experiments show that when sulphur and diethyldithiocarbamate are used in the butyl rubber vulcanization system, the butyl vulcanizate has a compression set of 71% at 100 ° C, and the butyl vulcanizate is compressed and deformed at 120 ° C. For 75%, the compression set of vulcanizate at 140 ° C is 81%, and when the temperature rises to 160 ° C, the compression set of butyl vulcanizate reaches 100%.
2 In the butyl rubber vulcanization system, when the accelerator DM and the p-benzoquinone dioxime are combined with sulfur, the compression set of the vulcanized rubber at 100 ° C is 75%, the compression deformation at 120 ° C is 84%, and the compression set at 140 ° C is 86. %, the compression set rate reaches 92% when the temperature rises to 160 °C.
3 When the combination of vulcanized resin SP-1055 and a small amount of neoprene rubber is used in the butyl rubber vulcanization system, the compression set at 100 ° C is 55%, and the compression set of butyl vulcanizate reaches 74% at 120 ° C. When the temperature rises to 140 ° C, the compression set of the vulcanizate is 79%, and the temperature of the butyl vulcanizate continues to rise to 160 ° C. The compression set of the butyl vulcanizate is 87%.
In summary, when using butyl reclaimed rubber to produce sealed rubber products, especially heat-resistant sealing rubber products, the choice of resin vulcanization can minimize the compression set of butyl reclaimed rubber vulcanizate at high temperatures.
2. Reinforcing filling system and softening plasticizing system
The type and amount of the compounding agent in the reinforcing filling system and the softening plasticizing system in the butyl reclaimed rubber sealing product also affect the heat resistance of the reclaimed rubber sealing article under compression. Studies have shown that reducing the amount of fine particle filler can improve the heat resistance of butyl reclaimed rubber seals under compression; the use of a small amount of petrolatum and paraffin in the softening plasticization system can further improve the heat resistance of butyl rubber under compression. Sex.
When butyl reclaimed rubber is used instead of butyl rubber to produce heat-resistant rubber seals, the type and amount of each compounding agent in the vulcanization system, reinforcing filling system and softening plasticizing system in the reclaimed rubber product formulation can be reasonably adjusted to improve the butyl group. The heat resistance of the reclaimed rubber sealing article under compression conditions, thereby extending the service life of the butyl sealing article.