High-density polyethylene blow moulding

Drop impact resistance of fluid-filled plastic containers is of considerable concern to containers manufacturers as well as distribution industries using the containers for transportation of various liquids. This is due to potential failure of the containers following the drop impact and subsequent spillage of the transported liquid, and consequent safety and economical Issues. In this work, a series of drop impact experiments is conducted on water filled bottles made of blow moulded high-density polyethylene (HDPE). During experiments, pressure and strain histories are recorded at various positions. The experiments are then simulated numerically. 

As an example of another form, co-extruded blow mouldings have been introduced to the market as containers for liquid detergents. The process used is known as sandwich blow moulding and provides a means by which recycled high density polyethylene can be incorporated again into a useful form by being employed between two layers of virgin material. 

Alpha Packaging manufactures botdes and jars made from polyethylene terephthalate (PET) and high-density polyethylene (HDPE) for the pharmaceutical, nutritional and personal care markets. Technologies used include injection blow moulding, injection stretch blow moulding, and extrusion blow moulding. Alpha manufactures stock and custom containers in a variety of styles and colours. 

HDPE exists as both a homopolymer and a copolymer with higher ethylene olefins. The latter offers properties which lie between low and high density, with typical densities of 0.945-0.950. Copolymers have found wide usage for extrusion blow, injection blow and injection moulding. They are, however, generally classified under HDPE. Virtually all high density polyethylenes contain an antioxidant. 

Blow moulding is a standard method for manufacturing automobile fuel tanks in high-density polyethylene. The tanks are often of very irregular shapes in order to utilize available space. What other method or methods could be used to make HOPE fuel tanks, and why is blow-moulding preferred ... 

The Acitainer (Acid container), designed and manufactured by Harcostar Ltd, Huntingdon, is a 45 1 (10-gal.) low-density polyethylene (LDPE) container enclosed and protected by a high-density polyethylene (HOPE) outer container. Both inner and outer containers are blow moulded and the combined unit offers a safer alternative to the conventional acid-carrying carboy. 

Whether an additive is used in concentrated masterbatch form or in its standard form will vary depending on the requirements of particular producers. Masterbatches are routinely used for blow moulding and film blowing in commodity plastics such as polypropylene (PP), LDPE and high-density polyethylene (HOPE). 

Blow moulding produces fairly good surface finish as for many items there is no further surface finishing necessary. Familiar products manufactured by blow moulding include drinks bottles, shampoo bottles, water dmms and plastic barrels. The plastics that are used in blow moulding include low density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene (PP). 

---