Stretch films containing random copolymer polypropylene resins in adjacent layers of a nanolayer structure

摘要

A method of producing a stretch film includes at least: extruding a first random copolymer polypropylene (RCPP) resin from a first extruder at a first temperature to at least one primary channel inside of a feedblock; extruding a second RCPP resin from a second extruder at a second temperature to at least one secondary channel, wherein said second temperature is greater than said first temperature; combining the first RCPP resin and the second RCPP resin to create a layered stream using a combining adapter disposed in communication with the feedblock; passing said layered stream from the combining adapter to a die; and passing the layered stream through said die to a casting unit. A multi-layered stretch film includes at least one nanolayer section, the nanolayer section comprising alternating substantially adjacent layers of a first random copolymer polypropylene (RCPP) resin and a second RCPP resin.

主权项

1. A method of producing a multi-layered stretch film, said method comprising:
extruding a first random copolymer polypropylene (RCPP) resin from a first extruder at a first temperature to at least one primary channel inside of a feedblock; extruding a second RCPP resin from a second extruder at a second temperature to at least one secondary channel inside of the feedblock, wherein said second temperature is greater than said first temperature, thereby creating a relative temperature gradient of at least about 30° F.; combining the first RCPP resin from the at least one primary channel and the second RCPP resin from the at least one secondary channel to create alternating substantially adjacent nanolayers using a combining adapter disposed in communication with the feedblock; passing said alternating substantially adjacent nanolayers from the combining adapter to a die; and passing said alternating substantially adjacent nanolayers through said die to a casting unit, thereby forming a nanolayer section of a film web.