What is the melting point for PS?

Polystyrene (PS) does not have a defined melting point because it is an amorphous polymer; instead, it has a glass transition temperature (Tg) of around 100 °C (212 °F). When heated, it softens gradually without a sharp transition from solid to liquid. For practical applications, it typically begins to lose its structural integrity at temperatures above 200 °C (392 °F).