疏水化修饰的聚N-异丙基丙烯酰胺高分子的水溶液性质研究

为了研究不同疏水化修饰的聚Ｎ 异丙基丙烯酰胺（ＰＮＩＰＡＭ）高分子的水溶液性质，合成了一系列Ｎ 异丙基丙烯酰胺（ＮＩＰＡＭ）和长链丙烯酸酯及丙烯酸胆固醇酯的共聚物．利用表面张力法证实了该类共聚物在室温下都具有良好的表面活性，在水溶液中能够形成胶束．利用荧光探针法，研究了共聚物的低温临界溶液温度（ＬｏｗｅｒＣｒｉｔｉｃａｌＳｏｌｕｔｉｏｎＴｅｍｐｅｒａｔｕｒｅ，ＬＣＳＴ），发现，随着丙烯酸酯碳链及其配比（摩尔投料比）的变化，共聚物的ＬＣＳＴ变化不明显，但它们都比均聚的ＰＮＩＰＡＭ要低；利用荧光偏振法研究了共聚物在水溶液中的微粘度，发现其微粘度不随共聚物中丙烯酸酯链长和配比的变化而变化，说明了该类共聚物在室温下能够形成相类同的胶束内核．

WATER SOLUTION PROPERTIES OF HYDROPHOBICALLY MODIFIED POLY(N-ISOPROPYLACRYLAMIDES)

To study the water solution properties of hydrophobically modified poly(N-isopropylacrylamides), the copolymers of NIPAM and a series of acrylic ester and cholesteryl acrylate were synthesized. The surface activity and micelle behavior of the copolymers in aqueous solution were deterimned by surface tension methods. Simultaneously, the Lower Critical Solution Temperature (LCST) of the copolymers was studied by fluorescence probe method. Results shows that the LCSTs of the copolymers have no obvious change with the change of the alkyl length of acrylic ester and the molar ratios of acrylic ester for the copolymers, but they are all lower than the homopolymer of Poly(N-isopropylacrylamide)(PNIPAM). The microviscosity of the copolymers in aqueous solution was studied by fluorescence polarization. Results show that their microviscosity do not change with the change of the alkyl length of acrylic ester and the molar ratios of acrylic ester for the copolymers. It indicates that at room temperature the copolymers can almost form the indetical micellar structure.