【摘要】 从高分子线团密度存在浓度依赖性角度出发,导出了从稀溶液至浓溶液范围内高分子链叠加度与浓度的定量关系式.以链叠加度为高分子溶液的结构参数,关联了文献中6种分子量的聚氯丁二烯在不同溶剂和温度条件下溶液相对黏度的变化.这表明,高分子溶液的宏观性质与溶液中高分子链叠加度这一微观结构参数密切相关.更多还原

【Abstract】 The radius of gyration is a good parameter for characterizing the dimensional distribution of a given polymer chain at perturbation conditions.But it is hard to give information about stack structures of polymer chains both in bulk and solution.It is highly desirable to establish the relationship between the micro-structure parameter and macroscopical properties of polymers in bulk or in solution.The degree of chain overlap is a good parameter for that,which has been defined and applied very well in bulk state.Based on Flory theory of intrinsic viscosity of polymers and the model of concentration dependence of polymer chain dimension in solution,a quantitative expression of the degree of chain overlap ξc,ξc≡c/pc=4πNnA/3Φ×{[η]c/1+([η]-[η]θ)/[η]θ[1-exp(-c/c)]},in terms of the concentration of the polymer solution from diluted solution to concentrated solution was deduced.A master curve of the relative viscosity ηr of polychloroprene solutions in literature for different molecular weights,various solvents and temperatures can be obtained as the ξc was used as a variable for replacing the concentration.It suggests that the micro-structure parameter of ξc and its quantitative expression proposed in solution state could correlate the macroscopical properties of polymer solutions,ηr,very well even at high concentration range.Also,ξc could be expected to be a promising micro-structure parameter for associating other properties of polymer in solutions.更多还原