Circle StressStrain Curve Letter A B C or D for each Polymer

Circle Stress-Strain Curve Letter (A, B, C, or D) for each Polymer Structure Tg = Glass Transition Temperature, below which a polymer is rigid and brittle

Solution

Thermoplastic polymers are rigid and brittle since they show drastic change in their properties above their glass transition temperature and below melting point. Thermoplastic polymers are different from thermosetting polymers or heat set polymers since the former form from  irreversible chemical bonds. Thermosets do not melt or deform upon cooling but gets decomposed upon heating where as thermoplastics reform under cooling. Hence in the given polymers the thermoplastic polymer of amorphous type example acrylics are more rigid as well as brittle.