Material information without obligation for PE (VLD, LD, LLD, MD, MLD, HD)
Physical Mechanical Properties
At 0,90-0,96 g/ccm PE is a very light material, where by VLD = Very Low Density 0,90 g/ccm and HD = High Density 0,96 g/ccm. In the natural state PE is water-resistant. PE is very brittle. The E module, the tensile strength and the surface hardness have low values. Good resistance to expansion cracks, principally in the case of VLDP and LLD/MLD-PE. With increasing density and increasing melting index PE becomes more sensitive as regards its stretching qualities.
The permanent temperature range for use without mechanical load are, in the case of VLD-PE -50° to 80°C and in the case of LD-PE -50° to 95°C and in the case of HD-PE -50° to 105°C. The material bursts into flames at about 340°C. PE burns also outside the flame, weakly glowing and then drips down burning.
Optical and Chemical Properties
Naturally-coloured PE is translucent. If the wall thickness is reduced. PE moulded parts become more transparent. Given correspondingly-designed injection-moulding tools VLD/LLD-PE articles demonstrate a very shiny surface. Natural PE articles are UV-sensitive and go yellow with time. PE is non-polar and is therefore not susceptible to very many chemicals. It is resistant to acids, lyes, alcohol, oil and salt solutions. HDPE is also resistant to benzine. VLD-PE and LD-PE swell in aliphatic and aromatic hydrocarbons. PE is not resistant to very strong oxidation media, e.g. nitric acid. The steam permeability level is small, gas permeability level is quite high however, in comparison to other plastics.
Physiological Behaviour and Joint
Physiologically, PE is no problem unless additives dangerous to health are used. Thanks to the excellent chemical consistency only impact glues can be used. The surface of the parts must be pre-treated very carefully-flame treatment, corona removal plus subsequent base coating. If possible the material should not be glued, instead heating elements, friction or not gas welding should be used.
Resistance to Weather and Ageing
PE is sufficiently resistant to radiation within the visible range. UV radiation produces oxidation and this is increased by the presence of oxygen. PE parts go brittle therefore on the surface and over disintegrate a long period. Suitable stabilisers can delay this process.
Special Uses, Products
Transport containers, shims, pipe plugs, furniture fittings, one-way assembly aids, substitution of soft PVC by VLD-PE for highly elastic articles.