水性聚氨酯的软段阻燃改性及其性能测试

Flame retardant modification of soft segment of waterborne polyurethane and its performance test

为提高水性聚氨酯(WPU)的阻燃性,以不同摩尔比的含磷聚酯二醇(BY3009T)和二聚酸聚酯二醇(BY3022)复配聚氨酯软段部分,二羟甲基丁酸(DMBA)为亲水扩链剂,与异佛尔酮二异氰酸酯(IPDI)反应,合成阻燃水性聚氨酯(BWPU)乳液。对未改性WPU和BWPU结构与性能进行表征与测试,分析BY3009T对聚氨酯乳液稳定性、力学性能、热学性能及阻燃性能的影响。结果表明:随着BY3009T含量的增加,乳液粒径变化不大,但稳定性和成膜性能逐渐变差,胶膜拉伸强度降低而断裂伸长率升高,极限氧指数先明显提升后趋于稳定。当BY3009T和BY3022的复配摩尔比n_(3009T)∶n_(3022)=3∶1时,改性后水性聚氨酯的综合性能最好,残炭量比未改性WPU提升了547.7%,极限氧指数(LOI)值达到28.3%,UL-94测试结果为V-1级。

In order to improve the flame retardancy of waterborne polyurethane(WPU),different molar ratios of phosphorus-containing polyester diol(BY3009T)and dimer acid polyester diol(BY3022)were used to compound the polyurethane soft segment part,dimethylol butyric acid(DMBA)as the hydrophilic chain extender,and then reacted with Isophorone diisocyanate(IPDI)to synthesize the flame retardant waterborne polyurethane(BWPU)emulsion.The structure and properties of unmodified WPU and BWPU were characterized and tested,and the effects of BY3009T on the stability,mechanical properties,thermal properties and flame retardancy of polyurethane emulsion were analyzed.The research results show that with the increase of BY3009T content,the particle size of the emulsion has little change,but the stability and film-forming properties are gradually getting worse,the tensile strength of the film decreases while the elongation at break increases,with the limiting oxygen index(LOI)increasing significantly and then becoming stabilized.When the compound molar ratio of BY3009T and BY3022 is n_(3009T)∶n_(3022)=3∶1,the comprehensive performance of the modified WPU is the best,the carbon residue is 547.7%higher than that of unmodified WPU,the LOI value reaches 28.3%,and the UL-94 test result is V-1.