高性能透明聚氨酯薄膜的制备及微相分离结构

Synthesis and Microstructure of High Performance Transparent Polyurethane Films

以自制的无规共聚支链聚酯多元醇和市售异氰酸酯为主要原料,成功制备出一系列高性能的透明聚氨酯薄膜。对聚氨酯薄膜的力学性能、光学性能、耐化学性、耐水解性能进行了测定,采用红外光谱(FT-IR)、广角X射线衍射(WAXD)、原子力显微镜(AFM)对其微相分离结构进行了表征。研究结果,表明聚酯多元醇中多种单体的共聚可以破坏其规整结构,阻止其结晶;聚酯多元醇或异氰酸酯中的环状结构可提高聚氨酯的力学强度;具有不对称结构的异氰酸酯或使异氰酸酯混合可以破坏聚氨酯内部的规整结构,降低其微相分离程度,但适度的微相分离对薄膜的透明性影响不大。

A series of transparent polyurethane films were synthesized using aliphatic isocyanate, with or without home-made copolymerized polyester polyol. The physical properties of the polyol were determined and the infrared （IR） spectroscopic analysis of polyols was reported. The physieochemical properties of polyurethane films were tested, and the microstructure was characterized by FT-IR, WAXD and AFM. The results indicate that the mixtur~~ of diacids and alcohols destroys the uniform structure and reduces the intermolecular interaction of polyesters. The structure and composition of isocyanate would influence the mechanical properties and surface morphology of polyurethane fihns. The cyclic structure in isocyanate improves the mechanical properties of polyurethanes, and the asymmetric structure in isocyanate or mixture of isocyanates destroys the regular structure of polyurethanes and reduces the degree of microphase separation. The modest microphase-separated structure in synthesized polyurethane networks does not trove significant influence on transmittance in the visible region.