Polyethylene is a long chain hydrocarbon thermoplastic material produced from the polymerization of ethylene. Polyethylene is relatively low priced, easily process able, highly impervious, and especially characterized by its high resistance to a wide range of chemically aggressive contaminants. Polyethylene is thus used worldwide as the preferred choice for waterproofing numerous earthwork structures such as landfills and industrial reservoirs. Manufactured in wide rolls, polyethylene liners come in varying thickness ranging from 20 to 100 mil (0.5 to 2.5 mm), as required by engineering design requirements. Polyethylene liners are also very reliable in exposed environments on account of their excellent low temperature brittleness resistance and superior protection against UV degradation.

◊HDPE (High Density Polyethylene):

High Density Polyethylene is the most chemically resistant member of the polyethylene family on account of its dense configuration (>0.94 g/cm3). It is extensively used for most containment structures. Although less flexible than its LLDPE counterpart, it still offers great elongation properties allowing up to 12% deformation at its yield point.

As its name implies, Linear Low Density Polyethylene is a lower density polymer (<0.939 g/cm3) yielding increased material flexibility. LLDPE is mainly used where large settlements are anticipated from long term consolidation such as landfill covers.

Polyethylene liners come in a variety of surface finishes, from smooth to heavily textured. Offering higher friction properties, textured materials are advantageously used when lining steep slopes by preventing slippage of adjacent materials. The level of texturing is described by the asperity heights which can range up to 10 mil (0.25 mm).