Virgin Grade HDPE pellets are freshly produced HDPE pellets that have never before been used in any manufacturing applications whatsoever. HDPE stands for High Density Polyethylene, and is a plastic that begins its life in the form of crude oil, from which naphtha is extracted, and then cracked at high temperatures to release ethylene gas. The ethylene gas is then put through a catalytic process, which causes the ethylene molecules to bond in long linear chains, creating polyethylene. High Density Polyethylene is simply polyethylene that is very molecularly dense due to a highly linear structure.
The HDPE emerges from the polymerization process as a very hot liquid, however, as it begins to cool, it quickly begins to solidify. This is due to one of the properties that make HDPE so very useful, that property being the fact that HDPE is a solid at room temperature. In order to make the Virgin Grade HDPE useful for manufacturing applications, before it is cooled entirely, it is extruded through a die with many small holes in it, and cut to length in the form of small pellets. The resulting product? Virgin Grade HDPE Pellets.
HDPE is therefore much stronger than other forms of HDPE, has a high level of chemical resistance (it is fairly inert), and is also lightweight and flexible, as well as having a pleasing translucent quality that takes color well and produces beautiful products such as children’s toys, garden furniture, and food packaging, amongst other things.
Caveat
Most of the time “grade” is a term used to refer to the Melt Flow Index, and is generally expressed as a function of the operations that are most suitably undertaken with that particular type of HDPE. For example, Injection Molding Grade HDPE has a high melt flow index, which means that it is highly viscous and will flow quickly into molds.
The title “Virgin Grade HDPE” is therefore a bit of a misnomer, which may be confusing to some who lump it in with other grades, such as Blow Molding Grade. It is possible to have Virgin HDPE that is Blow Molding Grade, or Virgin HDPE that is Injection Molding Grade. Virgin HDPE is simply a term to describe new HDPE that has freshly been created from a polymerization process and has never been used in any manufacturing applications whatsoever. Recycled/reprocessed/scrap HDPE can never be correctly termed as being virgin grade HDPE.