小角x射线散射结晶聚合物结构的研究

利用结晶聚合物的“三相结构”模型计算了结晶聚合物的一维电子密度相关函数,结论是三相模型的片层厚度和不变量与两相结构的意义不同.利用计算结果分析了一批样品的结构参量,发现用Ruland方法得到的结晶过渡层的厚度与用一维电子密度相关函数的结果是一致的.用Bragg定律求出的结晶聚合物的长周期与相关函数法长周期相差很多.这是因为两种分析结晶过渡层厚度的方法都是以样品电子密度的不均匀区为基础的,本质是一致的.但是Bragg法的长周期与相关函数法的长周期代表的范围不同 关键词： 小角x射线散射 结晶聚合物 三相结构 相关函数

Small-angle x-ray scattering study on the structure of crystal line polymer

The three phase structure model of crystal line polymer is used to calculate the one dimensional electron density correlation function.The conclusion is that the definitions of lamellar thickness and invariant are not the same as those in the two phase structure. Then utilizing this result to analyze some specimens,we found that the crystalline transition layer thicknesses obtained by the correlation function method agree with those by the Ruland method, but the long periods obtained by correlation function are much different from the Bragg spacings. The reason is that the two methods to calculate crystalline transition layer thicknesses are all based on the non homogeneous area of the specimen electron density and have the same nature. However, the Bragg spacing and the correlation function long period represent different regions of the non homogeneous area.