Description of PMMA Molecular Orientation due to Clustering Theoretical Model

Description of PMMA Molecular Orientation due to Clustering Theoretical Model 

This chapter discusses the independent determination of parameters for a cluster entanglement network enabling the accurate description of the experimental data on the molecular orientation in polymethyl methacrylate. This confirms the validity of the earlier proposed structural model for the polymer amorphous state [1, 2]. 

Two deformation schemes are commonly used to account for molecular orientation. These are the so-called affine and pseudoaffine schemes whose description, along with their applicability to real polymers, it given in a series papers [5, 6]. However, it turns out that the behaviour of the real polymers (amorphous as well as the semicrystalline ones) differs essentially from these schemes, entailing mmierous modifications [5, 6]. The main principle of all these modified and unmodified deformation schemes is the presence of a molecular entanglement network [7, 8]. 

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