Industrial sulfur powder plays a very important role in the rubber industry. It is a kind of rubber vulcanizing agent with excellent properties and low price. The emergence of vulcanizing agents makes rubber products appear in large numbers in our lives, which facilitates all aspects of our lives.
However, there are also some problems in the use of industrial sulfur powder as a rubber vulcanizing agent. In the process of processing, sulfur has high reactivity, which is easy to cause early scorching. In some rubber materials, in order to improve the modulus of the rubber, sulfur is sometimes used in large quantities. However, due to the limited compatibility between rubber and sulfur, the phenomenon of sulfur spraying out of the rubber surface often occurs, which also adversely affects the processing of rubber.
Of course, this sulfur ejection phenomenon also shows that the sulfur is not evenly distributed in the rubber matrix. When the vulcanization reaction occurs, this dispersion also leads to uneven vulcanization of the rubber, which affects the quality of the vulcanized rubber.
In order to solve the problem of ejection and scorching of vulcanized rubber, insoluble sulfur was discovered and applied to rubber production. Insoluble sulfur is a high molecular weight sulfur polymer, when used for rubber vulcanization, it will not migrate to the surface of the rubber, thus solving the problem of blooming; insoluble sulfur has low reactivity, thus avoiding the problem of scorching. At present, high-quality rubber tires generally use insoluble sulfur.
Although insoluble sulfur solves two major problems, it also exists in the compatibility of rubber. Insoluble sulfur is also insoluble in sulfur, so its dispersibility is difficult to ensure. In the process of rubber sulphur, high-density and low-density areas will still appear, which makes the mechanical properties of different areas different when the rubber is in use, which has a certain impact on the quality of the rubber.