Fluoropolymer based polymer processing additive (PPA) has been
used in LLDPE over a decade mainly to eliminate surface defects,
remove die build-up and reduce gel formation. PPA, however could
not find much usage in PP due to non-availabiity of suitable grade.
A new product known as Dynamar FX 5911 X has been developed by Dyneon
LLC, USA that is ideally suitable for PP. This new grade of PPA
is undergoing major development work in applications such as cast
film, BOPP and raffia tapes. These products are being manufactured
at increased output without affecting their product quality. The
new high performance PPA has a special role to play in this stricter
demand of higher productivity with more demanding performance. The
new PPA is designed for improved processibility of PP having lower
MFR that is needed to generate higher strength and lower moisture
permeation. For higher MFR PP, PPA allows processing at lower temperature
and thereby improves stability of polymer. The new PPA additive
is required to be used at 500 ppm level for reduction of die build-up
and about 1000 ppm level for gel control and enhanced productivity.
In BOPP, cigarette packaging film seems to have found greater usage
of PPA. the improved surface finish of cigarette packaging with
PPA is considered to be the key reason for it's acceptance. It seems
that the major benefits for PP processors are derived from enhanced
producitivity, lower rejections and reduction of machine downtime.
(Source : Modern Plastics
International October 2000) |
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