一种水溶性温敏共聚高分子的制备及溶液性质研究

Preparation and Solution Properties of a Thermo-sensitive Aqueous Solubility Copolyme

以N-异丙基丙烯酰胺和N-异丙基甲基丙烯酰胺为共聚单体,合成了一种在水溶液中具有与人体正常体温37℃一致的相转变温度的共聚化合物.利用动态光散射技术研究了这一特殊共聚物在水溶液中高分子链构象行为随温度的变化情况.

A series of copolymers of N-isopropylacrylamide (NIPAM) and N-isopropylmethacrylamide (NIPMAM) with different monomer ratios have been prepared well, whose transition temperature in aqueous solution have been measured by MicroCalorimenter respectively. The relationship of the transition temperature and their compositions have been set, and our results is coincident with those reported in ref.[1] However, it is interesting that when the composition of the NIPMAM monomer in the mixture monomers before polymerization was about 25%, a special thermosensitive copolymer, with a transition temperature near human heat of 37 ℃ in water, has been obtained successfully. In this article, the temperature dependence of the special copolymer conformation in water has been investigated by Dynamic Laser Light Scattering (DLLS) at the concentration higher than the critical concentration of the self-association according to cluster theory. From the DLLS experimental results, it was found that the hydrodynamic radius distribution of the polymer in solution had changed with temperature increasing. It was believed that there were two factors which affected the copolymer conformation and its size distribution in solution: one is the polymer coil shrinking, and the other is the self-association of the interchain.