扩链剂对脂肪族聚氨酯脲和聚脲弹性体结构与性能的影响

Effect of Chain Extenders on Structures and Properties of Aliphatic Polyurethaneureas and Polyureas

用异佛尔酮二胺(IPDA)、乙二胺(EDA)和己二胺(HDA)三种扩链剂合成了不同结构的脂肪族聚氨酯脲和聚脲,并考察了扩链剂对聚氨酯脲和聚脲形态结构与性能的影响.研究结果表明,与EDA和HDA扩链的聚氨酯脲和聚脲相比,IPDA扩链的聚氨酯脲和聚脲中脲羰基的氢键化程度较低,软段和硬段间的相混合程度较好;同时它们具有更好的拉伸强度、硬度和撕裂强度,但断裂伸长率较低.EDA和HDA扩链的聚氨酯脲和聚脲相比,两者性能相差不大.聚氨酯脲的脲羰基较完善氢键化程度以及整个氢键化程度都比聚脲的要低,同时聚氨酯脲的吸水率也较低.

A series of aliphatic polyurethaneureas （PUUs） and polyureas （PUAs） with various chain extenders were prepared. The influence of chain extenders on morphology and properties of these polyurethaneureas and polyureas was studied. The PUUs and PUAs synthesized with isophorone diamine （IPDA） showed lower degree of hydrogen bonding for the urea carbonyl groups existed in the system as well as better miscibility between soft and hard segments, compared to those prepared with ethylenediamine （EDA） or hexanediamine （HDA） as chain extenders. The tensile strength, hardness and tear strength of PUUs and PUAs prepared with IPDA were higher than those synthesized with EDA or HDA, but the PUUs and PUAs prepared with IPDA had lower elongation at break. There was little discrepancy in the properties of PUUs or PUAs extended with EDA and HDA. The degree of ordered hydrogen bonding for the urea carbonyl groups existed in PUUs was lower than that in PUAs prepared with the same chain extender, and PUUs also had lower water absorption content compared to PUAs prepared with the same chain extender.