LDPE FILM

LDPE is an abbreviation for Low Density Polyethylene. Polyethylene is made by polymerization of ethylene. (Poly means ‘a lot’; in fact, it means a lot of ethylene). Ethylene is obtained by cracking a light petroleum derivative such as naphtha.

The low density is obtained by the high-pressure polymerization process. This creates molecules with many side branches. The side branches ensure that the degree of crystallization remains relatively low. In other words, due to their irregular shape, molecules cannot lie in or on top of each other in a well-organized way, so that less of them fit in a certain space. The lower the degree of crystallization, the lower the density of a material.

A good example of this in daily life is water and ice. Ice is water in a (higher) crystallized state, and therefore much lighter than water (melted ice).

LDPE is a kind of thermoplastic. It is a plastic that softens when heated, unlike rubber for example. This makes thermoplastics suitable for reuse. After heating, it can be brought into other desired shapes.

LDPE film is an abbreviation for low density polyethylene film. The variety of Low Density Polyethylene (LDPE) film resins have evolved to match the myriad applications for specific large markets for LDPE films. What works for one application will not work for others. A few examples of resins which work only for specific LDPE plastic film applications are –  dry cleaner bags, bread bags, paper towel overwrap and shipping sacks.