| 摘要 |
<p>A solid polymer compsn. comprises (A) a copolymer of 10-25 wt.% acrylonitrile and/or methacrylonitrile, 40-65 wt.% butadiene and 25-38 wt.% styrene; and (B) a thermoplastic polyurethane having a urethane content of 45-80%, prepd. from a diisocyanate, diol mol.wt. 400) and hydroxyl-ended polyester (mol. wt. 800-4,000), using a NCO/OH ratio of 0.96-1.1:1. The ratio of (A) to (B) is 1:1-99. The compsn. has good impact strength at low temps. and is relatively inexpensive to mfr. The use of a copolymer contg. 50-60 wt.% butadiene and 12-18 wt.% acrylonitrile as (A); bis-(4-isocyanatophenyl)methane as the diisocyanate, and a caprolactone polymer, a polyester derived from a glycol and an aliphatic dicarboxylic acid, contg. a total of 3-5C in the form of methyl, methylene or methine gps. per ester gp., and having an acid value 6.0, or a copolymer of such a polyester and caprolactone, as the polyester is claimed.</p> |
