Extrudable polyvinyl alcohol compositions containing polyester-polyether block copolymers
AssigneeAir Products and Chemicals, Inc.
InventorsLloyd M. Robeson, Jeffrey A. Kuphal, Amir Famili
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Abstract
In a melt extrudable polyvinyl alcohol composition consisting essentially of polyvinyl alcohol and plasticizer, which has been made melt extrudable by adding sufficient energy to the polyvinyl alcohol to both melt and substantially eliminate the crystallinity in the melt while simultaneously removing energy from the melt at a rate sufficient to avoid decomposition of the polyvinyl alcohol, the improvement which comprises 5 to 25 wt % poly(butylene terephthalate)-polytetrahydrofuran block copolymer for improved impact resistance.
Claims19
In a melt extrudable polyvinyl alcohol composition comprising polyvinyl alcohol and plasticizer, the improvement for providing good impact efficiency which comprises 8 to 25 wt % thermoplastic polyester-polyether block copolymer, based on total composition.
In a melt extrudable polyvinyl alcohol composition comprising polyvinyl alcohol which is 75-99 mole % hydrolyzed and has a degree of polymerization from 200-2500 and plasticizer, the improvement for providing good impact efficiency which comprises 8to 25 to wt % thermoplastic polyester-polyether block copolymer, based on total composition, which is comprised of a multiplicity of recurring intralinear, long-chain and short-chain ester units connected head to tail through ester linkages with the long-chain ester units being represented by the structure:
- ##STR6## and the short-chain ester units being represented by the structure:
- ##STR7## where A is a divalent radical remaining after removal of the terminal hydroxy groups of a poly(tetrahydrofuran) glycol having a molecular weight (Mn) of from about 400 to about 4,000;
- B is a divalent radical remaining after removal of hydroxyl groups from ethylene glycol, butanediol or cyclohexane dimethanol;
- and R.sub.1 and R.sub.2 are independently 1,4-phenylene, 1,3-phenylene, naphthalene or cyclohexylene radicals.
In a melt extrudable polyvinyl alcohol composition comprising polyvinyl alcohol which is 85-98 mole % hydrolyzed and has a degree of polymerization from 200-2500 and plasticizer, the improvement for providing good impact efficiency which comprises 8 to 25 wt % thermoplastic poly(butylene terephthalate)-polytetrahydrofuran block copolymer, based on total composition.
Dependencies are inferred from the claim text.