Synthesis Of Waterborne Polyurethane And Flame-retardant Modified By HCCP

Waterborne polyurethane(WPU) has little odor, high molecular weight, low viscosity, easy processing, highly wear-resistant, strong adhesion, Simple operation, convenience store and easy to use, in leather, coating, textile, paper, printing and other fields are widely used, these materials prior to use if they are not fire-retardant treatment will be lurking posing a fire hazard, likely to cause significant casualties. Therefore, improve flame-retardant properties of WPU has a high value and very important social signif icance.In this paper, with polypropylene glycol(PPG), isophorone diisocyanate(IPDI), dimethylol propionic acid(DMPA), 1,4-butanediol(BDO) and trimethylolpropane(TMP) and others as raw materials, the use of the prepolymer dispersion synthesis WPU. By measuring the content of isocyanato, particle size testing, emulsion stability, measuring the viscosity of the emulsion, water resistance testing and mechanical properties testing methods, WPU synthesis of conditions and formulations were studied and discussed. The results showed that: to ensure WPU prepolymerization sufficiently stable during the reaction in each step, synthesis polyurethane prepolymer is first reacted at 45℃~55℃ for 20 min, then slowly warmed to 75℃, for about 100 min. Waterborne chain extender reaction at a temperature of 85℃ for about 120 min. Further expansion of the chain and a crosslinking reaction at 85℃ for about 120 min. WPU synthetic formulation research show results, increase the R values and TMP content can improve water resistance of WPU, R values, DMPA content and TMP content were increased, can be improve the hard segment content of WPU, so that the mechanical properties of WPU film, showing the tensile strength increased and elongation at break decreased.With hexachlorocyclotriphosphazene(HCCP), hydroxyethyl acrylate(HEA) and phenol(Ph OH) as raw materials, triethylamine(TEA) as the deacid reagent, by nucleophilic displacement reaction two-step synthesis of the five phenoxy cyclotriphosphazene acrylate(PCPA), using FTIR and 1H NMR characterization of the synthetic product PCPA. FTIR analysis shows the success of Ph OH and HEA substituted, simple post-processing product, the yield was 70%. By the method of free radical reactions will PCPA grafted onto the WPU molecular chain, PCPA modified WPU structure was characterized by FTIR. And through the emulsion stability, water resistance testing, mechanical properties, thermal gravimetric analysis, oxygen index test, vertical combustion test and other means testing the performance of PCPA modified WPU research. The results showed that: FTIR analysis shows PCPA successfully grafted to WPU molecular chain. With the increase of the content of PCPA, WPU emulsion particle size increases, a certain amount of PCPA can improve WPU film water resistance, increase PCPA content on the mechanical properties of WPU film has little impact. TGA and fire performance testing can be concluded that, increase PCPA content can be improved the WPU initial decomposition temperature, char yield and oxygen index, at 600℃, the unmodified WPU char yield only 0.158%, and when the PCPA content is at 6.43%, was 2.39% char yield, oxygen index of 27.2%, vertical flame test results for UL-94 V-1 level, it belongs to flame retardant materials.