Insoluble sulfur (cas 9035 99 8, hd7720 or 9035-99-8), the magical yellow powder, is not only non-toxic and flammable, it also has a special name origin - it does not dissolve in carbon disulfide. It is meticulously produced through the thermal polymerization process of ordinary sulfur, and has an astonishing number of sulfur atoms on its molecular chain, up to 108 or more, which gives it the viscoelasticity of a polymer and unique molecular weight distribution characteristics. Therefore, it is also affectionately called elastic sulfur or polymerized sulfur, which is a bright pearl in the field of inorganic polymer chemicals.
In the world of rubber, insoluble sulfur exists in its unique dispersed state, as if it is a silent guardian. It keeps the rubber material looking elegant, avoids frosting and gives it excellent adhesion. Insoluble sulfur is a boon to manufacturers who seek the perfect appearance for light-colored products.
In addition, insoluble sulfur is evenly dispersed in the compound, acting as an attentive guard to prevent sulfur build-up, thus reducing the risk of scorching during storage. It ensures the homogeneity of the properties of the adhesive components, prevents contamination of the products and molds, and makes the production process smoother. More importantly, it eliminates the need for an additional slurry application process to overcome frosting, providing strong support for production linkage.
In the adjacent adhesive layer, insoluble sulfur even demonstrates its non-migratory properties. This is particularly the case for the compounds (male and butyl), where the migration of ordinary sulphur is very fast, which is perfectly solved by the addition of insoluble sulphur. Even more surprisingly, insoluble sulfur also reduces the curing time. When the temperature reaches the vulcanization point, it seems to be activated and starts chain depolymerization, which makes the vulcanization speed up rapidly. This not only reduces the amount of sulfur, but also helps to improve the aging performance of the products, so that the service life of the products is longer.