LLDPE Raw Material

Production

Linear low density polyethylene with ethylene as the main raw material, with a small amount of α-olefin (such as 1-butene-1, 1-octene, etc.), under the action of catalyst by high pressure or low pressure gas-phase fluidized bed polymerization, the structural formula is -[CH2-CH2]n-, the reaction out of the material by granulation, drying, sent to packaging.

The production of LLDPE Raw Material started with transition metal catalysts, especially Ziegler or Philips types. New processes based on cyclic olefin metal derivative catalysts are another option for LLDPE production. The actual polymerization reaction can be carried out in solution and gas phase reactors. Typically, octenes are copolymerized with ethylene in a solution phase reactor to form butenes. Hexene is polymerized with ethylene in a gas phase reactor. The LLDPE Raw Material produced in the gas phase reactor is in pellet form and can be sold as a powder or further processed into pellets. Linear low density polyethylene is usually characterized by melt index and density. The melt index reflects the average molecular weight of the resin and is mainly controlled by the reaction temperature. The average molecular weight is independent of the molecular weight distribution (MWD). Catalyst selection affects MWD. Density is determined by the concentration of copolymer monomer in the polyethylene chain. The concentration of copolymer monomers controls the number of short branched chains (their length depends on the type of copolymer monomer) and thus the density of the resin. High pressure LDPE has long branched chains, while linear LDPE has only short branched chains.