Geomembranes can be manufactured from four main polyolefins: three from the polyethylene family, namely high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE) and very low-density polyethylene (VLDPE), and polypropylene (PP). Lower densities mean more flexible materials and increased weldability of the product, offset by reduced chemical resistance and mechanical strength, increased gas permeability and, in some cases, such as LLDPE, a 30% reduction in UV resistance.
In the specific case of PP, this material can provide the same flexibility as VLDPE but with significant chemical resistance, meaning it can be classified as a sort of hybrid material for special applications.
Geomembranes are determined by a series of parameters that describe both the type of raw material used and the quality of the geomembrane in terms of durability (UV resistance, chemical resistance to stress cracking and temperature). They also give an indication of the quality of the geomembrane transformation process and hence the manufacturer itself.
Atarfil’s technical data sheets group the properties of each of these concepts to make them easier to understand.
The following description gives a non-exhaustive summary of the meaning of certain properties to aid understanding and help users determine evaluation criteria. Please do not hesitate to contact Atarfil Technical Services for further information.