Polyolefin is a soft plastic film that is easily deformed by pressure and has good conformability. Examples are polyethylene and polypropylene.
Glossary
polypropylene
Polypropylene, abbreviated PP. Polyolefin film, similar in properties to polyethylene, but with higher heat resistance and strength.
polystyrene
Polystyrene is a colorless thermoplastic material formed as a result of the polymerization of styrene. It has excellent electrical insulating properties and is relatively unaffected by moisture. The film of this material breaks easily and has limited heat resistance.