Identify an common plastic part that is used below its glass

Identify an common plastic part that is used below its glass transition temperature, T_G, and tell what you think the temperature range is that it was designed to function in. Also, identify a part or product that must function above it\'s T_G.

Solution

Polystyrene is used well below its glass transition temperature of 95⁰C.It is designed to function in a temperature range of -50⁰C to 50⁰C.

Polypropylene is used above its glass transition temperature of -10⁰C in normal room temperarure range of 10-40⁰C.