Abstract: The invention provides an improvement in the suspension polymerization of vinyl chloride in an aqueous medium in the presence of a monomer-soluble polymerization initiator, according to which the amount of polymer scale deposition on the reactor walls can be greatly decreased. The improvement comprises admixing the aqueous polymerization medium with (a) a water-soluble crosslinked copolymer of an unsaturated carboxylic acid monomer, e.g. acrylic acid, and a crosslinking monomer such as di(methyl)allyl ether of diethyleneglycol and (b) a non-ionic surface active agent in combination.
Abstract: The invention provides an improvement in the suspension polymerization of vinyl chloride or a monomer mixture mainly composed of vinyl chloride in an aqueous medium containing a nonionic surface active agent and in the presence of a monomer-soluble polymerization initiator, according to which the aqueous polymerization medium is admixed with a crosslinked copolymer having carboxyl groups such as a copolymer of acrylic acid and diethyleneglycol bisallyl or bismethallyl ether at a moment when the percentage of the monomer conversion is in the range from 1 to 20% so that a polyvinyl chloride resin product of high quality can be obtained having an outstandingly high bulk density and plasticizer absorptivity but still containing an extremely small number of fish eyes.
Abstract: A process for modifying the surface characteristics of a pre-formed polymeric substrate to impart hydrophilicity, hydrophobicity, or other desired properties thereto, by peroxidizing the surface of the substrate and then allowing the active sites along the polymer chains to generate free radicals which induce graft polymerization of a suitable ethylenic monomer (or other ethylenically-unsaturated compound) onto the surface of the substrate is described. Such graft copolymerization is undertaken in the presence of variable valence metal ions in a reduced state under acidic conditions and at selected reaction times and relatively low temperatures, and ideally in the presence of squarate ions (diketocyclobutenediol) to control the physical characteristics of the surface graft and to restore the metal ions to their lower valence state without at the same time producing deleterious by-products.
Type:
Grant
Filed:
February 14, 1984
Date of Patent:
May 20, 1986
Assignee:
American Hospital Supply Corporation
Inventors:
Kenneth G. Mayhan, Robert A. Janssen, William J. Bertrand
Abstract: A 1,2-polymerization of 1,3-butadiene is carried out in a polymerization solvent in the presence of a 1,2-polymerization catalyst consisting essentially of a cobalt compound soluble in the polymerization solvent, an organic aluminum halide, an organic magnesium compound, and carbon disulfide and/or phenyl isothiocyanate and in the presence or absence of a cis-1,4-polymerization product of 1,3-butadiene.
Abstract: A polybutadiene rubber having an enhanced mechanical strength is produced in such a manner that the contents of water and carbon disulfide in a solution of 1,3-butadiene and carbon disulfide in an inert organic solvent is controlled to 0.2 to 5 m moles and 20 m moles or less, respectively, per liter of the 1,3-butadiene-carbon disulfide solution; a first polymerization mixture is prepared from the controlled 1,3-butadiene-carbon disulfide solution, an organic aluminum compound of the formula Al R.sub.n X.sub.3-n, wherein R=C.sub.1-6 alkyl, phenyl, or cycloalkyl, X=halogen, and n=1.5-2.
Abstract: A process for modifying the surface characteristics of a pre-formed polymeric substrate to impart hydrophilicity, hydrophobicity, or other desired properties thereto, by peroxidizing the surface of the substrate and then allowing the active sites along the polymer chains to generate free radicals which induce graft polymerization of a suitable ethylenic monomer (or other ethylenically-unsaturated compound) onto the surface of the substrate is described. Such graft copolymerization is undertaken in the presence of variable valence metal ions in a reduced state under acidic conditions and at selected reaction times and relatively low temperatures, and in the presence of squarate ions (diketocyclobutenediol) to control the physical characteristics of the surface graft and to restore the metal ions to their lower valence state without at the same time producing deleterious by-products.
Type:
Grant
Filed:
October 8, 1980
Date of Patent:
January 19, 1982
Assignee:
American Hospital Supply Corporation
Inventors:
Kenneth G. Mayhan, Robert A. Janssen, William J. Bertrand
Abstract: In a process for the production of a chemically blended composition of non-elastomeric ethylene resins in a multiplicity of steps in the presence of a catalyst composed of a transition metal catalyst component and an organometallic compound, which comprises (a) a step of forming (i) an ethylene polymer or an ethylene/alpha-olefin copolymer having an alpha-olefin content of up to 15% by weight, said polymer or copolymer (i) having an intrinsic viscosity [.eta.] of 0.3 to 3, and (b) a step of forming (ii) an ethylene/alpha-olefin copolymer having an alpha-olefin content of 0.2 to 30% by weight which is more than that of the polymer or copolymer (i), said copolymer (ii) having an intrinsic viscosity [.eta.] of 1 to 12 which is at least 1.
Abstract: Durable excellent water absorption property and antistatic property can be given to synthetic fiber by a simple method. In the method, a polymerization initiator is absorbed in the fiber and then the fiber is applied with a water-soluble polymerizable monomer and heat treated to form a polymer thereon.
Abstract: Rubber-reinforced alkenyl aromatic resinous polymers are prepared by polymerizing an alkenyl aromatic monomer such as styrene containing a reinforcing rubber until phase inversion occurs and subsequently adding an additional solution containing a reinforcing polymer such as rubber and containing polymerization.