Polyurethanes from Direct Organocatalytic Copolymerization of p-Tosyl Isocyanate with Epoxides

The direct copolymerization of p-tosyl isocyanate (TSI) with epoxides, initiated by onium salts in the presence of trialkylborane, to produce polyurethanes is reported. The rate of copolymerization and the (regio)selectivity were investigated in relation to the trialkylborane and the initiator used. Under optimized conditions such copolymerizations have been successfully performed for a wide range of epoxides, including ethylene oxide, propylene oxide, 1-octene oxide, cyclohexene oxide, and allyl glycidyl ether. These copolymerizations afford a new category of polyurethanes, clear of side products such as cyclic oxazolidinone, isocyanurate, and poly(isocyanate) linkages. The experimental conditions used in this work are compatible with those for the organocatalytic (co)polymerization of other oxygenated monomers and CO2, holding the potential for their terpolymerization with p-tosyl isocyanate and the development of new materials with unprecedented properties.

Automated summary

The direct copolymerization of p-tosyl isocyanate with epoxides using onium salts and trialkylborane as initiators has been successfully demonstrated, producing polyurethanes without side products. This study holds the potential for developing new materials with unprecedented properties through terpolymerization with other oxygenated monomers and CO2.