p-Toluenesulfonyl isocyanate

p-Toluenesulfonyl isocyanate (CAS 4083-64-1), also known as tosyl isocyanate or p-tosyl isocyanate, is a reactive sulfonyl isocyanate monomer carrying both isocyanate and sulfonyl functional groups. It carries no assigned E-code. It is supplied as a clear liquid under the HS code 29309090.

In polyurethane foam systems, the isocyanate group reacts with hydroxyl or amine components to drive cross-linking and control cell structure during foaming. In textile and leather processing, it functions as a biocidal and cross-linking agent, bonding to substrate polymers while inhibiting microbial growth. It is also used as a reactive colorant intermediate in coatings and adhesive formulations.

This material is supplied in compliance with REACH regulations and is registered under EC number 223-810-8. Standard packaging formats for laboratory and industrial procurement are available on request. Buyers should consult the current SDS for handling classifications prior to ordering.