Description of the molecular orientation of amorphous polymers in the framework of the cluster model

The article is devoted to the urgent problem of creating high-strength structural materials used in assemblies and parts of agricultural machinery. A successful way to solve this problem is to give a high degree of orientation to macromolecules. The degree of molecular weight is used as a characteristic of molecular orientation. To describe the molecular orientation, the cluster model of two macromolecular frameworks is used: molecular entanglements and molecular meshes. The important features of the cluster mesh of meshes in comparison with the mesh of entanglements are indicated. This goal is realized using the example of a simpler structure of the amorphous state of a polymer, polymethylmethacrylate, due to the lack of crystallinity in them. It is shown that information about the type and characteristics of the macromolecular framework involved in the orientation processes can be obtained from the results of measurements of birefringence from the degree of stretching. A comparison of the experimental and theoretical dependences of birefringence on the degree of extraction of amorphous polymethylmethacrylate showed a good agreement. It is shown that the parameters of the cluster mesh of meshes, determined by an independent method, allow a fairly accurate description of experimental data on the molecular orientation of polymethylmethacrylate. This, in turn, confirms the correctness of the structural model of the amorphous state of polymers.