Morphology solid polymers

For the analysis of the role of monomer diffusion during ethylene polymerization while forming a solid polymer a model of the polymer grain (see Fig. 2) has been suggested (95). This model is consistent with the results of the study of nascent morphology of the polymer and its porosity (95, 100, 103). According to this model three levels are considered in the analysis of transport phenomena. 

M. Neergat and A. K. Shukla. Effect of diffusion-layer morphology on the performance of solid-polymer-electrolyte direct methanol fuel cells. Journal of Power Sources 104 (2002) 289-294. 

I. M. Ward, Mechanical Properties of Solid Polymers, 2nd edn, John Wiley, New York (1983) A. E. Woodward, Understanding Polymer Morphology, Carl Hanser, Munich, Vienna (1995)... 

The morphology of solid polymers is also an important parameter. Thus, radiation-induced changes can be expected to differ in crystalline and amorphous regions — but in what way and to what extent "Crystallinity" and "amorphous" are not absolute terms and as more becomes known about the solid-state structure of polymers this should be related to radiation degradation. 

Fig- 13.29. Distribution of particle sizes in 10 wt. % Pt-C electrocatalyst. Particle sizes are average diameters. (Reprinted from E. A. Ti-cianelli, M. N. Beery, and S. Srinivasan, Dependence of Performance of Solid Polymer Electrolyte Fuel Cells with Low Platinum Loading on Morphologic Characteristics of the Electrodes, J. Appl. Electrochem. 21 601 copyright 1991, Fig. 9. 

A similar interpretation cannot be put on the cyclic ol omer concentrations of samples prepared starting with solid polymers containing (i) 11.5% w/w cyclic oligomers and (ii) no cyclic oligomers (see Fig. 18). Evidently the morphological structure of the samples of nylon-6 at 459 K prepared by starting with (i) and (ii) are similar. 

We have demonstrated that the structures, morphologies, and even chain conformations of solid polymer samples may be altered by including them in and then coalescing them from their CD-ICs. In addition to altering their physical behaviors, coalescence of guest polymers from their CD-ICs permits us to obtain solid polymer samples that are distinct from bulk samples made from their solutions and melts. Clearly study of such reorganized coalesced polymer samples can contribute to our ability to understand and develop improved structure-property relations for them. 

Michler, G. H. Morphology of Polymers Bethge H. Heydenreich J., Eds. Electron Microscopy in Solid State Physics Elsevier Amsterdam, Netherlands, 1987 p. 386. 

SAXS has been used to study the morphology of polymer blends in the solid state [Khambatta, 1976 Russel, 1979 Russel and Stein, 1982, 1983]. Eor example, in the interlameUar regions of PCL/ PVC blend the system is miscible on a molecular scale. Addition of PVC impeded crystallization of PCL. At high PVC concentration PCL remained in solution. The radius of gyration was larger than that under unperturbed conditions, in spite of the fact that at the same time the second virial coefficient, A, was virtually zero. SAXS was used... 

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