有机硅改性超支化聚氨酯的研究

首先制备了端基为羟基的超支化聚氨酯-脲（HPU）和异氰酸根封端的线性低聚物（A2）。以二者为原料制备了异氰酸根封端的超支化聚氨酯，并用适量的硅烷偶联剂（KH550）与异氰酸根反应进行改性。最后未反应的异氰酸根在大气环境下湿固化成膜得到了杂化聚氨酯。用红外光谱（FTIR）表征了产物的化学结构，讨论了产物中可能存在的氢键形式。研究了硅烷偶联剂（KH550）含量对聚合物热性能和力学性能的影响。研究结果表明，聚合物的耐热性能随着KH550含量的增加而增加，但其拉伸强度逐渐下降。

Study on the Hyperbranched Polyurethane Modified with Silicone

The hyperbranched polyurethane-urea(HPU) with OH end groups and linear oligomeric A2 with isocyanate terminated was prepared.Then the hyperbranched polyurethane with isocyanate terminated was synthesized with using HPU and A2 as raw materials and the products were modified by the reaction between excess NCO and proper silicane coupling agent(KH550).At last the remaining excess NCO completely formed into hybrid polyurethane by moisture curing under atmosphere circumstance.The chemical structure of the polymers was characterized by FTIR,and possible hydrogen bond formation existed in the products were discussed.The effects of the KH550 content on the thermal properties and mechanical properties of the polymer were discussed.It was found that the heat resistance of polymers was better and better with the increasing content of KH550,but the tensile strength decreased.