Under normal conditions, the ethylenic polymers are not toxic, and can even be used in contact with food and pharmaceuticals products , however certain additives can be aggressive. In the past, the polyethylene was classified by its density and the type of process used in its manufacture. Currently, polyethylenes are more appropriately described as branched and linear chain polyethylenes.
Depending on the reaction conditions and the catalytic system used in the polymerization, five different types of polyethylene can be produced:
- Low density polyethylene (LDPE or LDPE).
- High density polyethylene (HDPE or HDPE).
- Linear low density polyethylene (LLDPE or LLDPE).
- Polyethylene ultra high molecular weight polyethylene (UHMWPE or UHMWPE).
- Ultra low density polyethylene (ULDPE or PEUBD)LDPE – Low Density Polyethylene