MDI基热塑性聚酯型聚氨酯弹性体性能的研究

以4,4′-苯基甲烷二异氰酸酯（MDI）、聚己二酸丁二醇酯二醇（PBA）、1,4-丁二醇（BDO）为原料,采用一步法合成热塑性聚氨酯弹性体（TPU）。在n（—NCO）/n（—OH）（R值）恒定条件下,研究了PBA相对分子质量、BDO添加量与TPU性能关系,并由红外光谱、热重、X射线衍射分别表征了TPU的结构、热性能和结晶特性。研究发现：R值、BDO量和MDI量恒定时,PBA的相对分子质量越高,TPU的拉伸强度、断裂伸长率均呈增加趋势;R值恒定,以相对分子质量3 000的PBA为原料,TPU的拉伸强度、断裂伸长率均随BDO添加量的增加而增加;TPU的热分解温度高于300℃,结晶特性显著。

Study on properties of thermoplastic polyester polyurethane elastomer based on MDI

Thermoplastic polyurethane elastomer（TPU） was synthesized by one-shot process with 4,4′-diphenylmethane diisocyanate（MDI）,poly-butylene adipate gylcol（PBA） and 1,4-butanediol（BDO） as raw materials.When R value was the same in the experiment,the influences of molecular weight of PBA and addition amount of BDO on the properties of TPU were studied.Moreover,structure,thermal property and crystallinity of TPU were characterized by FT-IR,TGA and XRD,respectively.The results were as follows.When R value,addition amount of BDO and addition amount of MDI were certain,with the increasing of molecular weight of PBA,tensile strength and elongation at break of TPU were increased.When R value was certain and PBA with molecular weight of 3000 was used as a polyester component,with the increasing of additon amount of BDO,tensile strength and elongationat break of TPU were also increased.Additionally,the thermal decomposition temperature of TPU was above 300℃ and its crystallinity was significant.