D14.
State the requisites of an elastomer.
An elastomer can be described as a cross-linked polymer, which
glass-transition temperature is below the temperature used when the elastomeric
properties are studied. A way to visualize the structure of an elastomer is to
say that there are large polymer coils, and that these coils are held together
by a network of cross-linkages. When the elastomer is stretched, the coils
uncoil and increase their energy levels. When the stretching force is removed,
the stretched coils recoil again in order to decrease their energy levels. To
conclude, an elastomer is a cross-linked resin which glass-transition
temperature has been exceeded.
