Study of the carbamate/aldehyde reaction, a new pathway towards NIPU materials

An innovative alternative to the synthesis of non-isocyanate polyurethanes (NIPUs) thermoset materials was thoroughly investigated. This pathway, involving reaction between primary carbamate functions and aldehyde functions, studied using model reactions ethyl different aldehydes that lead highlights key parameters as well first reported proposed mechanism for this reaction. In a second time, polycarbamates synthesized from two polyols were via transcarbamoylation before participating in polycondensation with monoaldehydes. First linear NIPU oligomer dicarbamate derived ethylene glycol benzaldehyde. product analysed by NMR spectroscopy MALDI-TOF mass spectrometry. exhibited low molar masses attributed many secondary termination reactions, mainly due presence acetic anhydride used solvent Cross-linked then without solvent, tricarbamate trimethylol propane vanillin, biobased monoaldehyde, time. The process these optimized obtain thermosetting networks gel fraction (GF) dimethylsulfoxide (DMSO) up 82%, Tg values ranging 39 °C 65 depending on GF value. study brings much needed highlight little-known carbamate/aldehyde demonstrates its potential novel coatings simple monoaldehyde such vanillin.