| 摘要 |
<p>1455752 Graft polymer compositions MONSANTO CO 8 Jan 1974 [9 Jan 1973 1 Oct 1973- 00749/74 Heading C3G A resin is produced by mixing, at 120‹ to 180‹ C., (A) from 50 to 90 parts by weight of a first composition comprising (a) from 40 to 80% by weight of a first copolymer of a monovinylidene aromatic monomer and an alkene nitrile in a weight ratio of from 90 : 10 to 10 : 90, the copolymer having a weight average molecular weight of from 75,000 to 500,000; and (b) the balance up to 100% of a monovinylidene aromatic monomer and an alkene nitrile in a weight ratio of from 90 : 10 to 10 : 90; the composition having the physical form of a homogeneous hot melt and an initial temperature of 130‹ to 180‹ C.: and (B) correspondingly from 50 to 10 parts of a second composition comprising (a) from 30 to 69À9% by weight of a graft polymer of a substrate of an alkadiene elastomer whose glass transition temperature is below 0‹ C. and a superstrate of a copolymer of from 90 to 10 parts of a monovinylidene aromatic monomer and 10 to 90 parts of an alkene nitrile, the amount of graft superstrate being from 5 to 75 parts for every 100 parts of substrate and the weight average particle size of the graft polymer being from 0À25 to 2À0 microns; (b) from 0À01 to 40% of a second copolymer of from 90 to 10 parts of a monovinylidene aromatic monomer and from 10 to 90 parts of an alkene nitrile, the second copolymer having a weight average molecular weight of from 50,000 to 500,000; (c) from 69À9 to 30% of an organic liquid having a boiling point of from 25‹ to 150‹ C. at atmospheric pressure which is substantially non-chemically reactive with the graft polymer and causes the graft polymer to swell by not more than 25% by volume; and (d) from 0 to 15% by weight of water: the second composition being in the form of a dispersion of the graft polymer in the organic liquid and having an initial temperature of from 0‹ C. up to the boiling point of the liquid; and introducing the mixture into a flash vaporization zone where it has a surface to volume ratio of at least 2À5 : 1 and maintaining the mixture in the zone at from 120‹ to 280‹ C. and a pressure of 0À001 to 800 mm. of Hg absolute for from 1 to 10 minutes while removing vapours volatilized from the mixture from the zone such that, when removed from the zone, the devolatilized mixture comprises at least 97% by weight of a combination of the first and second copolymers and the graft polymer. The organic liquid in the second composition may be styrene and/or acrylonitrile. The mixing and introduction into the vaporization zone may be conducted sequentially or simultaneously. Examples are given in which a dispersion of styrene-acrylonitrile copolymer in styrene and acrylonitrile is mixed with (a) a dispersion in acrylonitrile of a graft polymer formed by grafting styrene and acrylonitrile on to particles of mixed butadiene-acrylonitrile rubbers having sizes of about 0À28 Á and about 0À68 Á.</p> |
