HDPE Impervious Geomembrane

Product Description: 

Geomembranes are generally considered to be made from continuous, highly impermeable, extruded flexible sheets of either HDPE (High Density Polyethylene) or LDPE (Low Density Polyethylene). However, it is also possible to tightly weave small tape fibres of these polymers so as to achieve (either directly or by subsequent treatment) an impermeable membrane. Predominantly, the continuous extruded sheets are used for water containment or waste disposal linings. These inevitably involve the lining of soil slopes and, in order to increase the frictional characteristics of the membranes, so as to resist sliding, one or both sides of geomembranes can be provided with roughened or raised profile surfaces. 

Applications:

Geomembranes have a very low coefficient of permeability - much lower than most clays and natural soils. HDPE, in particular, is highly resistant to any form of chemical or biological attack. It is also very resistant to U.V. degradation. Many geomembranes are so inert that they cannot be glued together - the chemical reactions of adhesives do not work on them - they have to be welded together by heat. Their inert nature and long life characteristics make HDPE geomembranes ideal to act as liners for liquid chemical reservoirs, fresh-water reservoirs, animal waste containers, basal linings and top capping layers for waste disposal sites. During installation, HDPE geomembrane edges are sealed to one another with a double heat welded joint. The gap between the two welds is checked for leakage using an air pressure test. Many users consider that HDPE is the ideal material for the purpose of lining water and waste disposal sites because of its proven long term stability and resistance to chemical attack, but in addition to HDPE, there is LDPE, for less demanding applications such as fresh water retention and a membrane reinforced with a polyester reinforcing fabric for use where higher in-plane stresses have to be absorbed.