Process Study On Preparation Of Insoluble Sulfur With Low Temperature Melting Method

Insoluble sulfur is allotrope of general sulfur with amorphous structure. Due to its structure and the structure of the polymer is similar, so also named as poly-sulfur.Oil-filled high grade insoluble sulfur products with high temperature stability, has become irreplaceable vulcanizing agent of radial tires production.The study mainly focuses on production process of insoluble sulfur with low temperature melting method, taking industrial first grade sulfur as raw material to replace general sulfur powder used in rubber. The process mainly includes three parts: polymerization (preparation of middle grade insoluble sulfur), extraction (preparation of high grade insoluble sulfur), and filling oil. Test equipments and factors affecting the insoluble sulfur performance such as the polymerization reaction temperature, reaction time, amount of stabilizer, drying time, as well as extraction temperature, extraction time and solid-liquid ratio and other parameters were discussed and researched. Finally process parameters of insoluble sulfur production with low temperature melting method are fixed, and product properties are also tested. Test results indicate that, all properties of oil-filled high grade insoluble sulfur prepared under this process are superior to chemical industrial standard HG/T2525-2011; and its property is close to that of imported insoluble sulfur product.