聚N-异丙基丙烯酰胺溶液的粘度的温度依赖关系

用自由基聚合法合成了聚Ｎ 异丙基丙烯酰胺（ＰＮＩＰＡＡＭ）样品，用乌氏粘度计考查了该聚合物的四氢呋喃（ＴＨＦ）溶液和水溶液的粘度与温度的依赖关系．发现ＰＮＩＰＡＡＭ ＴＨＦ体系的特性粘数随温度升高而增大，ＰＮＩＰＡＡＭ Ｈ２Ｏ体系的特性粘数 温度曲线表现出较为复杂的变化规律．并用实验确定的特性粘数对合成样品的分子量进行了表征Ｍｎ＝８４４×１０５ｇ·ｍｏｌ－１．

THE TEMPERATURE DEPENDENCE OF VISCOSITY OF POLY(N|ISOPROPYLACRYLAMIDE) SOLUTION

Poly(N isopropylacrylamide) (PNIPAAM) was synthesized by free radical polymerization.By means of Ubbelodhe viscosimeter,the temperature dependence of viscosity of PNIPAAM THF and PNIPAAM H 2O systems was tested.The relative viscosity of PNIPAAM THF system was found linear increased with temperature increased,the higher the temperature was,the larger the viscosity deviated from Einstein's theory for viscosity of suspension,the dispersed substance was found tended to linear structure in high temperature.But the relative viscosity of PNIPAAM H 2O system was found inereased slow with temperature increased and the transformation points were found,the higher the temperature was,the littler the viscosity deviated from the Einstein's theory,the dispersed substance was found tended to globular structure in high temperature.The intrinsic viscosity of PNIPAAM THF system was found increased with temperature increased,but the intrinsic viscosity curve of PNIPAAM H 2O system was quite complex,and the step declining curve was found.But the viscosity curve of PNIPAAM H 2O system was quite complex.The intrinsic viscosity determined by experiment was also used to characterize the molecular weight of PNIPAAM M n =8 44×10 5g·mol -1 .