三官能度聚醚型聚氨酯弹性体的力学性能研究

以三官能度的聚醚多元醇、1,4-丁二醇和二苯基甲烷二异氰酸酯(MDI)为主要原料合成了聚氨酯弹性体。研究表明,硬段质量分数超过50%以后,伸长率降低,交联时间对聚氨酯(PU)弹性体整体的力学性能影响不大。在保持异氰酸酯指数为1.0和MDI含量不变的条件下,把1,4-丁二醇和聚醚多元醇的羟基摩尔比提高到1.50:0.33,材料的力学性能最佳。随着交联时间的增加,拉伸强度及硬度先增大后减小,伸长率呈减小的趋势。

Mechanical properties study on polyurethane elastomers of three functionality polyether

Polyurethane elastomers were synthesized from 1,4-butylene diol, MDI and three functionality polyether polylol. Investigation showed that elongation to break decreased in polyurethane elastomers when content of hard segments was high- er than 50%. Vulcanization time did n＇t effect properties of polyurethane elastomers remarkably. Issocyanate index and molar number of MDI were kept at 1.0, and 2 respectively changing the ratio of between polyether polylol and 1,4-butyle＇ne diol, results showed that ratio is 1.50：0.33, properties of polyurethane elastomers was optimum and polyurethane elastomers became viscous when content of 1,4-butylene diol was enough high.