不同软段热塑性聚氨酯弹性体的合成及性能研究

The Synthesis and Properties of Thermoplastic Polyurethane Elastomers Based on Different Soft Segment

以聚己二酸丁二醇酯二醇(PBA)、聚己内酯二醇(PCL)、聚碳酸酯二醇(PCDL)和聚四亚甲基醚二醇(PTMG)作为软段,采用一步法制得4种热塑性聚氨酯弹性体(TPU)。通过FTIR、电子拉力试验机、DSC、TGA和DMA分析研究了软段结构对TPU的物理机械性能、热性能和动态力学性能的影响。结果表明,在软段分子量和硬段含量相同时,PTMG-TPU和PCL-TPU较PBA-TPU和PCDL-TPU具有较低的硬度、模量、压缩永久变形和较高的弹性。PBA-TPU和PTMG-TPU显示较高微相分离程度和热稳定性;PCDL-TPU则显示较高的相混合程度。在低于玻璃化转变温度(Tg)时其储能模量降低次序为PCDL-TPU>PBA-TPU>PCL-TPU>PTMG-TPU,Tg增大的次序为PTMGTPU<PCL-TPU≈PBA-TPU<PCDL-TPU。

Four thermoplastic polyurethane elastomers （TPU） with different soft segment based on poly （oxytetramethylene） glycol, poly （ 1,4-butylene adipate ） glycol, poly （ 8-caprolactone ） diol and polycarbonate glycol were synthesized by one-step method. The physical and mechanical properties, thermal and dynamic mechan- ical properties of TPU were mainly studied by FTIR, electronic tensile tester, TGA, DSC and DMA analysis. The results showed that, when the molecular weight of soft segment and the hard segment content were the same, PT- MG-TPU and PCL-TPU had lower hardness, modulus, compression set and rebound than PCDL-TPU and PBA- TPU, PBA-TPU and PTMG-TPU showed higher microphase separation degree and thermal stability, PCDL-TPU showed higher phase mixing. Under the glass transition temperature （ Ts） , the storage modulus of the TPUs reduced in order of PCDL-TPU〉PBA-TPU〉PCL-TPU〉PTMG-TPU. Their Ts increased in order of PTMG-TPU〈PCL-TPU≈ PBA-TPU 〈PCDL-TPU.