LLDPE, additives Processing aids

Productivity also reportedly remained high with the new additive. In monolayer bag extrusion runs with LLDPE/LDPE blends, a 65% reduction in processing aid, using the 102725 product, sttH allowed a 150tn/minute Une speed and 9001b/ hour output from a 22-in die. In co-extrusion, a 6-ln die outputted 470 Ib/houi, with the additive loaded at 80% less than the other product. 

The latest Viton FreeFlow additives are among those that have a reduced tendency to interact with other constituents of the formulation. Another new non-reactive fluoropolymer additive has been developed by Dyneon in association with 3M Canada to overcome similar problems, and has been found to perform well in LDPE and LLDPE film. The later versions of Dyneon polymer processing aids act as effective process aids in polyamides and PU, without the usual discoloration and processing problems. 

Fluoroelastomers are useful as processing aids. The fluoropoly-mers are normally in the fluid state at room temperature (2). The effect of the addition of an elastomer to linear low density poly(eth-ylene) (LLDPE) is shown in Figure 11.1. 

In addition an acrylic based processing aid improves the extrusion of high density poly (ethylene) (HDPE). However, the use of this processing aid provides only a marginal improvement in the extrusion of LLDPE having a narrow molecular weight distribution (7). 

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