含乳酸酯基端—NCO预聚体的交联过程研究

Study on the cross-linking process of end—NCO precursor containing lactate unit

通过测定含乳酸酯基端—NCO预聚体的交联产物及其在常温下大气中静置不同时间的红外光谱、凝胶分数以及力学性能,分析了交联反应过程及其对产物性能的影响。实验结果表明,—NCO基团特征吸收峰的强度在一周内明显下降直至消失,而凝胶分数和力学性能则基本不变;交联产物为具有一定机械强度和韧性的多孔状材料,其拉伸强度、弹性模量、弯曲强度和弯曲模量的平均值分别为10.8、86.2、17.7和102.3 MPa。

The cross-linking process of end-NCO precursor containing lactate unit was examined via measuring the infrared spectra, gel fractions and mechanical properties of samples exposed to the air for different time. FTIR showed thai the NCO-group remained at firsl and would disappear wilhin one-week, while no evident change was found for the gel fractions and mechanical properties of samples, h was also revealed that cross-linked polymer was a kind of porous material with the tensile strength, elastic modulus, bend strength and bend modulus of 10.8,86.2,17.7 and 102.3 MPa respectively.