Linear Low – Density Polyethylene

Linear low density polyethylene (LLDPE) is a substantially linear polymer (polyethylene), with significant numbers of short branches, commonly made by copolymerization of ethylene with longer -chain olefins.  Linear low-demsity polyethylene (LDPE) because of the absence of long chain branching. The linearity  of LLDPE results from the different manufacturing processes of LLDPE and LDPE. In general, LLDPE is produced at lower temperature and pressures by compolymerization of ethylene and butane, Helene, or octene. The copolymerization process produces an LLDPE polymer that has a narrower molecular weight distribution than conventional LDPE and in combination with the linear structure, significantly different theological properties.

Application

LLDPE has penetrated almost all traditional markets for polyethylene ,it is used for plastic bags and sheets (where it allows using lower thickness than comparable LDPE), plastic warp, stretch wrap, pouches, toys, covers, lids, pipes, buckets, and containers, covering of cables, geomembranes (1)and mainly flexible tubing. In 2013,theworld market for LLDPE reached a volume of $40 billion.  (2)

LLDPE manufactured by using metallocene catalysts is labeled mLLDPE.

Physical properties

(example)

(l -l)