梯度热处理聚氨酯脲弹性体的红外光谱分析

对均匀温度场中制得的聚氨酯脲弹性体在梯度温度场中进行梯度热处理,控制不同的温度梯度和处理时间,得到一系列试样.用傅立叶变换红外光谱(FTIR)对试样进行表征,结果表明,梯度热处理试样的结构呈现梯度变化的趋势.在试样内部从高温到低温端微相分离程度逐渐降低.并且热处理的温度梯度越大或时间越长,相分离的梯度也越大.拉伸测试表明,热处理提高了试样的拉伸强度,断裂伸长率却有所下降.

Infrared analysis on polyurethane-urea elastomer treated in graded temperature field

Polyurethane-urea elastomers prepared in an uniform temperature field were treated thermally in graded temperature field. A series of samples were obtained by changing magnitude of temperature gradient and time. FTIR technique was used to characterize the microphase separation of the samples. The results indicate that the degree of microphase separation within the samples increases gradually from the lower- temperature end to the higher end. Moreover, increasing the heat treatment temperature gradient or time will lead to the increase of the gradient of degree of microphase separation. Tensile tests show that heat treatment enhances the tensile strength but decreases the elongation at breaking point. Elongation properties of samples are related to their gradient of microphase separation degree.