Polyethylene (PE) is a semicrystalline thermoplastic polyolefin produced through the polymerization of ethylene monomer (CH₂=CH₂), characterized by a saturated hydrocarbon backbone composed of repeating –[CH₂–CH₂]– units. Its nonpolar molecular structure, combined with variations in chain branching, molecular weight, and molecular weight distribution, governs crystallinity, density, mechanical strength, flexibility, and melt processing behavior. The absence of polar functional groups contributes to low moisture absorption, favorable dielectric properties, and resistance to numerous aqueous chemicals, while its semicrystalline morphology determines stiffness, impact toughness, and thermal performance. Commercial PE resins are primarily classified into Low-density polyethylene (LDPE), Linear low-density polyethylene (LLDPE), and High-density polyethylene (HDPE), distinguished by their branching architecture, crystallinity, density, and resulting processing and mechanical characteristics.

PE Grades