Glassy polymers polyvinylchloride

Some of the prominent glassy polymers that we consider in the second family that can exhibit rubbery behavior above their Tg are polystyrene (PS), polypropylene (PP), polyvinylchloride (PVC), and polymethyl methacrylate (PMMA). These are shown in Fig. 2.1 in Chapter 2. 

CO2 is well known for its plasticising effects in glassy polymers and in polyvinylchloride (PVC) this effea starts above 10 bar. 

As might be expected, there are polymers intermediate between the crystalline and glassy ones. For example, polyvinylchloride shows enough Older to prevent its classification as glassy, but not enough to be considered crystalline. 

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