Amorphous material/polymers/regions transparency

The physical properties of random copolymers are determined by their location on the diagram, that is, by their composition and use temperature. In region 1, the polymer is a homogeneous, amorphous, and, if pure, transparent material. The distinction between melt and rubbery behavior is not sharp At higher temperatures, the material flows more easily and becomes less elastic in character. It should be kqpt in mind, though, that the vi sities of polymer melts, even well above Tg or T , are far greater than those encountered in nonpolymeric materials. 

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