Processing aids for enhanced machine direction orientation rates and property enhancement of polyolefin films using hydrocarbon waxes
AssigneeEquistar Chemicals, LP
InventorsRobert J. Bowling, D. Ryan Breese
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Abstract
The present invention disclose a method for the orientation of a high density polyethylene (“HDPE”) film. The process of the invention comprises forming a HDPE-wax mixture by adding to a HDPE batch a normally solid hydrocarbon wax. The HDPE-wax mixture is subsequently stretched into a film at an orientation temperature below the film's melt temperature. The hydrocarbon wax is characterized by having a drop point equal to or lower than the melting point of the HDPE film. The present invention also provides a film made by the process of the invention and a master batch thereof.
Claims8
A process forming an oriented high density polyethylene (HDPE) film, the process comprising:
- forming a HDPE wax mixture by adding to HDPE a normally solid hydrocarbon wax having a molecular weight from about 1000 to about 4000 in an amount of from 0.02 weight percent to about 1.0 weight percent, said weight percents based on the sum of the weights of HDPE and the hydrocarbon wax, said HDPE being substantially free of filler such that filler-created microvoids are substantially avoided;
- and
- stretching the HDPE wax mixture into a film at an orientation temperature below the film's melt temperature,
- wherein the hydrocarbon wax has a drop point lower than the melting point of the HDPE film.
Dependencies are inferred from the claim text.