Process for producing synthetic pulp from a film of a mixture of polypropylene and low density polyethylene

  • US 3,950,473 A
  • Filed: 05/21/1973
  • Issued: 04/13/1976
  • Est. Priority Date: 12/20/1971
  • Status: Expired due to Term
First Claim
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1. A process for producing a synthetic pulp which comprises:

  • a. making a composition consisting of1. 50 to 90 parts by weight of polypropylene having a melt flow rate of 30 to 150 as measured at 230°

    C and under a load of 2.16 kg and2. 50 to 10 parts by weight of low density polyethylene,into a film having a thickness of 70 μ

    or less,b. uniaxially stretching the resulting film to at least 8 times its original length,c. cutting the film thus stretched to lengths of 5 mm or less, andd. fibrillating the cut film lengths by passing them through at least two clearances having a distance of 5 mm or less formed between a plurality of linear projections on the inner peripheral surface of a cylindrical casing and the tip ends of at least two sets of a large number of vanes rotating therein at a peripheral speed of 92 - 100m /sec. whereby a crumpling and disintegrating action mainly by blows and a whirling air stream is brought about to effect fibrillation, ande. recovering a synthetic pulp having the following characteristics

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