Linear Low Density Polyethylene Resins

Linear low density polyethylene (LLDPE) is a copolymer of ethylene with an α-olefin (propylene, 1-butene, 1-hexene or 1-octene). The LLDPE has linear molecular structure with short branching and narrow molecular weight distribution as compared with low density polyethylene (LDPE). The short chain branches has influence either LLDPE or LDPE , on the morphology and some physical properties such as stiffness, density, hardness and tensile strength. The properties of LLDPE films are attributed to its linearity and crystallinity. The molecular structure of the LLDPE is essentially linear due to the type of catalyst used. Their crystallinity, although much lower than HDPE, is greater than LDPE. This increased crystallinity in addition to linear polymeric chains, positively affect the mechanical properties of the films without causing a decrease in their optical characteristics. Compared to HDPE, LLDPE presents the tensile strenght and hardness lower as much as increasing content of ramifications, and exhibits greater resistance to impact and tearing (films). LLDPE is a thermoplastic with high capacity for heat sealing, being widely used in packaging of commodities , replacing LDPE in several applications. And used in films for industrial use, disposable diapers and absorbent pads in general, toys, pharmaceutical and hospital, wire and cable coating. The tubular film extrusion provides materials for packaging . In blends with HDPE or LDPE, LLDPE and used in industrial sacks, food packaging and agricultural film. The cast film extrusion provides products for use in plastic bubble. LLDPE can be used for injection caps for domestic use, containers, flexible articles and parts of general use.