Research On The Synthesis And Function Of Water-based Non-isocyanate Polyurethane

Traditional non-isocyanate polyurethane (NIPU) Synthesized by cyclic carbonate and multi-amine is given more and more attention because of its non-toxicity. NIPU do not contain isocyanate which do harm to the environment and human in the process of production and application. The waterborne NIPU, which use water as dispersion medium, can reduce the use of solvents effectively with the advantages of safe, non-toxicity, convenient operation processing.Cyclic carbonate DOMA was synthesized from glycidyl methacrylate (GMA) and CO2in the presence of the solvent and catalyst with high temperature and high pressure. In order to improve productive rate, the effects of factors were discussed such as temperature, pressure, catalyst, time and solvent. Crude product was obtained by means of washing, extraction and vacuum distillation, and the higher purity quotient of DOMA was refined by means of thin-layer chromatography and column chromatography,and the product yield content was examined by high performance liquid chromatography analysis. Experiments showed that the yield of DOMA was up to82.8%on the condition that the solvent was cyclohexane,the catalyst was tetra-butyl-ammonium bromide and Iron TPP, reaction temperature was110°C, reaction pressure was1.2MPa,and the reaction time was4hours.DOMA had been characterized by means of FT-IR,13C-NMR,1H-NMR,which proved that functional groups and structure of the product after the reaction were in accordance with DOMA.The obtained molecular weight conformed to the expected product of DOMA by means of HLPC-MS detection of molecular weight.Waterborne-NIPU film was obtained by the reaction of diethylenetri-amine and emulsion,and the emulsion which contained cyclic carbonate structure was synthesized by polymerization reaction with acrylic acid, acrylic esters and the homemade DOMA monomers. The film structure was characterized by FT-IR. The experiment investigated the monomer content, reaction temperature and reaction time’s influence on the emulsion stability,and discussed the monomer content, curing temperature and curing time’s influence on the film surface and mechanical properties. The experiments showed stable emulsion was formed under the conditions:DOMA monomer was no more than20%in the emulsion reaction, the acrylic monomer was not less than4%in the reaction, reaction temperature was65°C, reaction time was5h. As the content of acrylic acid increased, the water contact angle of NIPU film decreased with the higher curing temperature and longer curing time,the much improved water absorption on the film surface.