HDPE as a material
High-density polyethylene (HDPE) is a polyolefin, a polymer made from petroleum-based monomers. Polyethylene is one of the most versatile plastics of all time and is used in different variants in almost all areas of life. HDPE represents a major subcategory of the polyethylene (PE) that is most widely used worldwide.
HDPE - Questions & Answers
HDPE can be used in temperature ranges from -50 to 70°C. This makes it very popular for packaging food, chemicals, and cosmetics, among other things. When uncolored, the plastic has a milky transparent appearance and is hard but flexible at room temperature. The widespread use of this thermoplastic material is due to several advantages. Compared to glass as a packaging material, it is significantly more break-resistant and, at 0.94 g/cm³ to 0.95 g/cm³, considerably lighter.
Compared to LDPE produced using high-pressure processes, HDPE is more resistant to abrasion, more diffusion-tight, and also stiffer.
Thanks to its mechanical stability, the material retains its shape even with large volumes and is therefore ideal for the production of dimensionally stable bottles and canisters. In addition, HDPE is easy to process and weld. HDPE is a very versatile plastic. In addition to a wide variety of packaging for liquids, creams, or solids, it is used to manufacture pipes, blinds, foam mats, and even entire boats, among other things. This is why HDPE has become the most widely used plastic outside the packaging industry. This is made possible by its excellent dimensional stability in temperature ranges from -50°C to 70°C. Another advantage is the durability of PE. The denser the polyethylene, the more pronounced this property is. The wide variety of materials that can be wrapped in HDPE packaging makes this plastic very interesting for a whole range of products. In addition, the plastic is physiologically harmless. HDPE therefore poses no health risks. HDPE is suitable for packaging food, cosmetics, and pharmaceutical products.
Since the material is chemically very stable, it can be used to contain salts and salt solutions or bases and acids, for example. Organic solvents such as fats, oils, waxes, and alcohols are also well suited for packaging made from HDPE. Unfortunately, chlorinated hydrocarbons and oxidizing acids cannot be packaged with this material. HDPE is therefore an excellent and inexpensive packaging material for many solvents.
However, UV light causes this versatile packaging material to become brittle. This can cause it to lose some of its beneficial properties. HDPE packaging should therefore be protected from prolonged exposure to sunlight.
HDPE can be colored in many different shades. To achieve this, color masterbatches are added during production. These are granules containing pigments on a PE carrier material. Just 1-2% of these granules are enough to ensure opaque coloring in the melting process. HDPE can be printed using screen printing. There are inks available that dry immediately with the help of UV light. The rubber coating on self-adhesive PE or PP labels also adheres well and permanently to HDPE containers.
HDPE is made from oil and is not biodegradable or compostable. However, HDPE is 100% recyclable. It is detected by near-infrared scanners in recycling plants, sorted, shredded, cleaned, and processed back into granules. Old bottles and cans can be turned into new containers or other consumer goods. Even in residual waste, HDPE still has a use. It burns without leaving any residue or releasing harmful substances and has a good calorific value. This means that it meets the recycling standards of the DIN EN 13427 series, with the exception of compostability (DIN EN 13432).
Therefore, be sure to put HDPE waste in the recycling bin. It is not plastic that is responsible for environmental pollution, but humans and their actions.