widely used for technical parts, rigid containers, caps, tubes, and tanks
LDPE (Low-density polyethylene)
Trade Name : Hostalen, Lupolen, Vestolen
✓ This material meets the criteria ~ Specialized grades may meet this criteria
| Density | 0.941 to 0.984 g/cm³ ISO 1183 |
|---|---|
| Charpy notched impact | 1.2 to 29 kJ/m2 |
| Flexural modulus | 758 to 1540 MPa ISO 178 |
| Flexural resistance | 25 MPa |
| Tensile modulus | 752 to 1360 MPa ISO 527-1 |
| Tensile resistance | 11.3 to 27.3 MPa ISO 527-1, -2 |
| Tensile strain | 6 to 1000 % ISO 527-1, -2, Break |
widely used for technical parts, rigid containers, caps, tubes, and tanks
LDPE has a very strong chemical resistance due to the non-polar nature of polyethylene. It is generally unaffected by aqueous solutions of salts, acids, and alkalis, and it withstands many solvents up to approximately 60°C, subject to actual usage conditions. This very good inertness explains its success in canisters, tanks, piping, and technical packaging.<br />
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However, LDPE is not recommended when exposed to strong oxidising agents, notably nitric acid, fuming sulphuric acid and halogens. As always, the thickness, stressed areas, processing quality and actual service conditions heavily influence the final performance of the component; therefore, testing under actual usage conditions remains the best validation.
Injection at 180–250 °C, mould at 20–60 °C. Low viscosity → good filling. High shrinkage (1.5–3.0 %) → adjustment of mould dimensions essential. Crystallisation influenced by cooling rate. No pre-drying required.
Is HDPE recyclable?<br />
Yes. HDPE corresponds to resin code #2 and is presented by the source consulted as one of the most widely and effectively recycled plastics. This good recyclability explains its major role in rigid packaging and material reuse applications. <br />
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Le PEHD est bien recyclé car il s'agit d'un plastique polyvalent, abondant et dont la valeur est relativement élevée par rapport à d'autres plastiques. Il est utilisé dans une grande variété de produits, ce qui contribue à la disponibilité des matériaux recyclés. De plus, le PEHD est assez facile à trier et à nettoyer, ce qui en fait une cible attrayante pour les installations de recyclage. Le processus de recyclage du PEHD est également bien établi et efficace, générant un matériau qui peut être utilisé pour fabriquer de nouveaux produits de haute qualité, tels que des bouteilles, des tuyaux, des jouets et des meubles.<br />
Because it benefits from a mature collection, sorting, washing, grinding and regranulation process, particularly for rigid packaging. Its value increases significantly when clean, natural rHDPE, with little contamination from pigments, labels, metals or adhesives, is obtained. <br />
What elements complicate its recycling?<br />
Elements that hinder recyclability include dark or black caps, overly covering labels, adhesives that do not separate well during washing, certain metal components, and decorations unsuitable for optical sorting. The APR stresses the need to design HDPE packaging so that it remains detectable and separable in automated sorting lines.
Some grades of polyethylene can be used for food contact, but this is never an “automatic” property of any HDPE material. Compliance depends on the grade, additives, process, intended use, and available regulatory documentation.<br />
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The framework is Regulation (EU) No 10/2011 on plastic materials intended for contact with food. The essential idea, for a material data sheet, is that the compliance of the final product relies on migration, intended use, and the transmission of a Declaration of Conformity throughout the supply chain.<br />
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In the United States, 21 CFR 177.1520 covers olefin polymers, including polyethylene, for food contact applications. The text sets specifications for density, extractables and leachables, and notably distinguishes polyethylene used for standard articles, for cooking-related uses, or as a component of food contact coatings.
The LDPE (Low-Density Polyethylene) is a technical thermoplastic known for its robustness, lightness, very good chemical resistance, and very low water absorption. It is particularly suitable for the manufacture of rigid containers, injection-moulded parts, tubes, caps, and components exposed to humidity or common chemicals.
LDPE is easily processed, generally doesn't require pre-drying for injection moulding, and benefits from excellent recyclability, especially within its specific recycling stream. Code 02.
However, for food-contact applications, a grade specifically complying with applicable regulations and accompanied by its conformity documentation should be selected.