METHOD OF PRODUCING POLYMER SULFUR Russian patent published in 1997 - IPC

FIELD: sulfur production. SUBSTANCE: invention relates to producing, in presence of active additives, heat resistant high-molecular polymer sulfur to be employed in tire and rubber industries as nonbleeding vulcanizing ingredient. Method is distinguished with that, in the stage of breaking initial sulfur or in the stage of its melting, fine-dispersion hydrophobic silicon dioxide (0.1-1.0 wt.-%) is added and sulfur is melted in presence of 1-2 wt.-% of hexachloro-p-xylene preliminarily heat treated at 110-150 C for 20-40 min. Further, temperature of melt is elevated to 210 C, kept for 30-40 min, whereupon melt is rapidly cooled with water, crushed, and soluble allotropic sulfur modifications are extracted with organic solvent. Yield 72-90%, thermal stability of product is 0.15-0.48%/min. EFFECT: enhanced efficiency of process. 1 tbl