PVC (Polyvinyl chloride) is available in two variants: PVC – HD and PVC – LD. The material has an amorphous structure and, for this reason, it is often used for the production of optically clear pressed pieces. It is very tough material with low resistance to high and lower temperatures. It is characterized by low resistance to atmospheric agents. It may be harmful to health (there exists also a variant safe for health though), it can be easily welded and glued. PVC – LD is in fact PVC – HD containing an admixture of plasticizer (the material elasticity depends on the admixture quantity) and its shrinkage is greater than in case of PVC – HD.
