LDPE, the first of the polyethylenes to be developed, is characterized by good toughness and flexibility, relatively low heat resistance, low-temperature impact resistance, and clarity in film form. Like the medium and high-density grades, LDPE has good resistance to chemical attack. At room temperature, it is insoluble in most organic solvents but is attacked by strong oxidizing acids. At higher temperatures it becomes increasingly more susceptible to attack by aromatic, chlorinated and aliphatic hydrocarbons.

Polyethylene is susceptible to environmental and some chemical stress cracking. Wetting agents such as detergents accelerate stress cracking. Some copolymers of LDPE are available with improved stress-crack resistance.

About half of LDPE production goes into packaging applications such as industrial bags, shrink bundling, soft goods and produce and garment bags. Other applications include blow-molded bottles, large industrial containers and toys; hot-melt adhesives; injection-molded housewares; paper-board coatings and wire insulation. LDPE resins are rotationally molded into large agricultural tanks, chemical shipping containers, tote boxes and battery jars.

One of the fastest growing plastics today is linear low density polyethylene (LLDPE) used mainly in film applications but also suitable for injection, rotational and blow molding.

Properties of LLDPE are different from those of conventional LDPE and HDPE Impact, tear and heat-seal strengths and environmental stress-crack resistance of LLDPE are significantly higher. Major uses at present are in film products - industrial trash bags, liners and heavy-duty shipping bags for such products as plastic resin pellets.