Study on synthesis process of p-Toluenesulfonyl semicarbazide

p-Toluenesulfonyl semicarbazide used as blowing agents in polypropylene processing was synthesized recurring to three-step reactions. In the first step, adding a certain amount of salts in the preparation of p-toluenesulfochloride from toluene and chlorosulfonic acid has a favorable effect on improving yield of p-Toluenesulfonyl chloride. In the second step, the yield of p-toluene sulfonhydrazide using tetrahydrofuran as solvent is higher than that of using benzene as solvent. The reaction temperature has obviously effect on the yield of p-Toluenesulfonyl Semicarbazide.