The Polystyrene standard differs in the fluidity, in the heat-deflection temperature and in the stiffness, including the antistatic applications for the injection molding, the extrusion and rolling.
The High-Impact Polystyrene has different levels of hardness and fluidity for injection molding and extrusion.
The polystyrene is resistant to the water, the alcohol and to the diluted mineral acids, as well as to the aqueous solutions of the most of the salts. However it expands itself in some organic solvents and dissolves itself in others. This is true for the hydrocarbons, ethers, esters and the aromatic and chlorinated ketones.
Besides the Polystyrene it’s etched from the concentrated sulfuric acid and from the strong oxidizing agents, for example nitric acid, chlorinated water, brominated water and hypochlorites solutions of sodium.