Improving Polymer Processability Utilizing Constrained Geometry Single Sue Catalyst Technology

Constrained geometry single site catalyst technology has enabled Dow Chemical to produce a new family of homogeneous copolymers which expand the horizons of polyolefins. This INSITE'0 technology makes it possible to control the amounts of long chain branching (LCB) and short chain branching (SCB) to produce a polymer that has the good physical properties obtained with a narrow molecular weight distribution (MWD, where Mw/M. 2) and yet has good processability-as described in this paper. For example, in a typical melt extrusion process, these new polymers are less susceptible to melt fracture than the other homogeneous (narrow MWD) polyolefins and even the broader MWD heterogeneous polyolefins such as linear low density polyethylene (LLDPE) and ultra low density polyethylene (ULDPE).