Rigid segments, property-structure

Without clarification of the real causes of these changes in the intensity of bands, connected with fluctuations in rigid segments, we can only assert that they are determined by the influence of optimal concentrations of chemically modified filler on the polymer structure as a whole, and in the case imder discussion on the structure of permole-cular formations of rigid blocks in particular. Alteration of the whole association structure is not necessary the transition layer at the phase boundary is enough. Probably, the extremal character of the dependences of certain physical and mechanical properties of the filled polymers on the filler concentration (mainly for the extremum at small concentrations) is connected with this. In any case, the extremal values of adhesion strength that we observed may be explained from this starting point. 

Cooper et al. [68-70] investigated the effect of butylene terephthalate and butylene isophthalate unit content in the rigid segment on the physical properties and structure of PEE. The isophthalate influences the crystallization and melting conditions of the PEE hard phase. This is directly related to the material mechanical properties. 

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