Polymers, glassy Terms Links

An elastomer is defined as a cross-linked amorphous polymer above its glass transition temperature. Elastomers may be stretched substantially reversibly to several hundred percent. While most of this chapter explores the behavior of elastomers, the study of cross-linking is more general. If the cross-linked polymer is glassy, it is often called a thermoset. Below, the terms elastomer and rubber are often used interchangably. 

At temperatures in excess of in Fig. 8.2, the not very well-defined melting temperature, these polymers are completely amorphous and show many of the features characteristic of liquids, the condition being termed viscofluid. Rapid cooling of the polymer from state A (Fig. 8.2) causes it to follow the path ABC, whether it it cross-linked or not. The polymer is amorphous at all stages along ABC, shows little or no change in specific volume at and when the temperature is below it is essentially glassy. 

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