Polypropylene provides excellent resistance to organic solvents, degreasing agents and electrolytic attack. It has a lower impact strength, but its working temperatures and tensile strength are superior to low or high density polyethylene. It is lightweight, resistant to staining, and has a low moisture absorption rate. This is a tough, heat-resistant, semi-rigid material, ideal for the transfer of hot liquids or gases. It's recommended for vacuum systems, where higher heats and pressures are encountered.
• Good chemical resistance.
• Good dielectric properties.
• It is physiologically inert, so in natural form, it is approved for use in contact with food.
• Low specific gravity.
• Good stability to temperature.
• Compared to the engineering plastics it has low thermal and mechanical properties: tensile stress, flexural and compressive strength, etc. Compared to PE it is more rigid but less shock resistant.
Polypropylene is commonly used for mechanical components in corrosive environments such as the chemical industry. This is due to its high resistance to acids and alkalis and a high temperature resistance. Typical components are: