Why Can't Rubber Seals Increase The Vulcanization Temperature Indefinitely?

Temperature is one of the three major elements of vulcanization. Like all chemical reactions, the vulcanization reaction accelerates as the temperature rises, and Vanter Hoff’s law generally applies, that is, every 8-10°C increase in temperature (approximately equivalent to a gauge pressure) Steam pressure), the reaction speed is approximately doubled; in other words, the reaction time is approximately reduced by half. With the increase of room temperature vulcanization compounds and the emergence of high temperature vulcanization, the vulcanization temperature tends to two extremes. From the perspective of improving vulcanization efficiency, it should be considered that the higher the vulcanization temperature, the better, but in fact, the vulcanization temperature cannot be increased indefinitely. First of all, the thermal conductivity of rubber is very small. For thick products, it is difficult to use high temperature vulcanization to make the inner and outer layers of rubber reach a flat range at the same time; second, the high temperature resistance of various rubbers is different, and some rubbers cannot withstand the effects of high temperature. For example, when natural rubber is vulcanized at high temperature, the oxygen dissolved in the rubber will increase in activity with the increase of temperature, causing strong oxidation, destroying the structure of the rubber, and reducing the physical and mechanical properties of the vulcanized rubber. Third, the high temperature will affect the rubber products The harmfulness of the textiles in the cotton fabric is that when the cotton fiber cloth is overdue at 140 ℃, its strength will drop, and it will be completely destroyed when heated at 240 ℃ for four hours.