Abstract: An improved method for preparing polyvinyl chloride resins by suspension polymerization wherein the reaction vessel is placed under a limited, selected atmosphere of air, oxygen or nitrogen gas prior to charging starting vinyl chloride monomer material.

Abstract: Biocompatible polymeric microspheres having an average diameter below about 3 microns and having a density at least 15% greater or lesser than organic cells and having covalent binding sites are provided in accordance with this invention. The microspheres are obtained by copolymerizing a hydroxy or amine substituted acrylic monomer such as hydroxyethylmethacrylate with a light or dense comonomer such as a fluoromonomer. A lectin or antibody is bound to the hydroxy or amine site of the bead to provide cell specificity. When added to a cell suspension the marked bead will specifically label the cell membrane by binding to specific receptor sites thereon. The labelled membrane can then be separated by density gradient centrifugation.

Abstract: Polymers and copolymers of vinyl chloride having a narrow grain size distribution and a large average mean diameter and a process for the preparation of same in which the polymerization of vinyl chloride is carried out in the presence of a prepolymer composition obtained by polymerization, under high turbulence, of a monomeric composition containing vinyl chloride and acrylic acid or methacrylic acid, an aliphatic ester thereof or a diester of a dihydric alcohol.

Abstract: Spontaneously cross-linked alkali metal acrylate polymers having a high water-absorbing property and which are safe for contact with the human skin are prepared by a water-in-oil suspension polymerization process, using a sorbitan fatty acid ester having an HLB value of 3 to 6 as a dispersing agent.

Abstract: A process for the polymerization of vinyl chloride which comprises adding to an aqueous dispersion of vinyl chloride polymer prepared by a suspension polymerization process, optionally containing vinyl chloride monomer, or a bulk polymerization process the additives necessary for emulsion polymerization, then effecting the polymerization of the vinyl chloride monomer present in the reactor prior to introducing the emulsion polymerization additives and/or vinyl chloride monomer added after the introduction of these additives.Vinyl chloride polymers comprising vinyl chloride polymer particles produced by suspension or bulk polymerization having vinyl chloride granules agglutinated thereon said granules having the dimensions of vinyl chloride granules obtained by conventional emulsion polymerization.

Abstract: Micro-suspension polymerization of vinyl chloride monomers and comonomers with a seed in the form of a previously prepared dispersion of the polymer or copolymer containing all of the organo-soluble initiator required for the polymerization, in which the initiator is activated during the polymerization by the addition of an organo-metallic complex of a water-soluble metal salt reacted with a complexing agent.

Abstract: A one-step process for the emulsion polymerization of vinyl chloride using a water-soluble initiator and an aqueous emulsifier system of (1) a C.sub.12 -C.sub.18 straight chain alkyl or alkenyl phosphate surfactant and (2) a C.sub.12 -C.sub.20 straight chain alkyl or alkenyl alcohol and/or a straight chain saturated hydrocarbon having a carbon content of greater than 18 is disclosed. One suitable example of a straight chain phosphate surfactant is sodium lauryl phosphate. Suitable alcohols include stearyl alcohol, cetyl alcohol and eicosanol. A suitable hydrocarbon is eicosane. The resulting homo- and copolymer latices can be used in plastisols and organosols.

Abstract: A powdery copolymer having a powder particle size from 0.1 to 200 microns, said copolymer comprising at least 50 percent by weight of methyl methacrylate and 0.2 to 10 percent by weight of at least one monomer having a basic nitrogen atom, the balance, if any, being other monomers copolymerizable therewith, said copolymer being prepared by emulsion copolymerization such that all or a predominant portion of the monomer or monomers having a basic nitrogen atom is first added to the remaining monomers after the polymerization of at least half of said remaining monomers, the resulting copolymer then being recovered from the resultant latex in powder form.

Abstract: Water-swellable, cross-linked, bead copolymers of (A) an ethylenically unsaturated monomer having a carboxylic acid anhydride, glycidyl or succinimide group, (B) a comonomer having at least two radical-polymerizable carbon double bonds, and (C) a radical-polymerizable water-soluble comonomer are disclosed to be excellent carriers capable of bonding with biologically active substances such as enzymes, enzyme substrates, inhibitors, hormones, antibiotics, antigens, and peptides.

Abstract: Solid titanium trichloride in the form of fine granules having low aluminum compound content, which is suitable as a catalyst for polymerization of .alpha.-olefins, especially, propylene is obtained as a precipitate by heating liquefied titanium trichloride in the presence of a liberating agent, and separating the thus formed precipitate. The liquefied titanium trichloride is preferably prepared with an reducing titanium tetrachloride by organic aluminium compound in the presence of ether and hydrocarbon.

Abstract: Polymerization of ethylene using a transition metal hydrocarbyl complex, especially zirconium tetrabenzyl, supported on alumina consisting of substantially spherical particles having diameters in the range 20-150 .mu.m. The particulate polymer produced by the process contains substantially no "fines" (i.e. particles <100 .mu.m diameter) and has improved pourability.

Abstract: There is provided a process for preparing water-soluble polyelectrolytes by a water-in-oil emulsion process. A mixture of a surfactant, free radical initiator, at least one water-soluble, oil-insoluble, ethylenically unsaturated monomer adapted to polymerize under refluxing conditions, oil and water (the oil and water being adapted to form an azeotropic boiling mixture) is heated with vigorous agitation. The monomer polymerizes at the reflux temperature under the vigorous agitation with a concomitant simultaneous loss of water. Finely divided, water-soluble particles result.

Abstract: A method for preparing substantially dry homopolymers and copolymers which comprises forming a polymeric latex or water-in-oil emulsion and partially inverting said latex by regulated contact time with water in the time span 0.5 - 10.0 seconds and preferably less than 1 second. A preferred operation is carried out in a static mixer where the contact time for inversion is regulated by the diameter or length of a cylindrical tube containing static baffles.

Abstract: There is disclosed a polymerization process for the preparation of large chloroprene polymer particles having an average diameter in the range of from 0.15 to 2.0 microns. The process utilizes a polymerization medium and catalyst system that produces a substantially monodisperse particle size distribution of polychloroprene rubber particles in an aqueous dispersion, said particles having great utility as a rubber phase in thermoplastic polyblends.

Abstract: In a process of bulk vinyl chloride polymerization involving a two stage stationary reaction zone polymerization wherein high speed agitation is used during the first stage and slow speed agitation is used in the second stage, the polymerization in the first stage is conducted in contact with an organic or inorganic, inert, fine particle size material, solid at least at reaction temperatures and insoluble in the monomer or monomers used, or an anionic, cationic, or nonionic surfactant, or mixtures thereof. By the present polymerization method using economical conventional agitation equipment, small particle size polyvinyl chloride homopolymers or copolymers are produced which are useful as extender resins in plastisols.

Abstract: There is disclosed a process for producing carboxyl-containing hydrophilic polymeric fillers comprising polymerizing at least one carboxyl-containing monomer with a cross-linking monomer in an oxygen bearing organic solvent for the monomers and in the presence of a free radical catalyst to form a polymeric precipitate and treating the thus formed polymeric precipitate with a solution containing sodium, potassium or ammonium ions thereby transforming the same into the corresponding polymeric salt, said solvent being a non-solvent for the polymer.

Abstract: Process for manufacturing finely divided polymers of bicyclo [2.2.1] heptene-2 compound comprising the steps of incompletely polymerizing said bicyclo [2.2.1] heptene-2 compound by the ring opening polymerizing technique in the presence of a catalyst system selected from the group comprising a compound of a noble metal of the platinum family and an alcohol-reducing solvent and tungsten hexachloride, an aluminum alkyl and an aromatic solvent, under superatmospheric pressure and in the presence of a quantity of solvent at least equal to that necessary for the solution of said catalyst system and abruptly reducing said pressure at a temperature higher than the vaporization temperature of the reaction mixture under said reduced pressure, whereby an expansion, a division and at least partial drying of the resulting polymer is obtained.

Abstract: Emulsions of ethylene homopolymer and/or copolymers are provided which are remarkably clear and have a light transmission of at least about 95%, and contain particles which have an average size no greater than about 100 angstrom units. These emulsions are produced by polymerizing ethylene, or ethylene with at least one other alpha unsaturated monomer in aqueous medium in the presence of an effective amount of a water soluble persulfate initiator, from about 2 to about 5 percent by weight based on the aqueous medium of an alkyl aryl sulfonate surfactant, and from about 0.3 to about 0.7 percent by weight based on the aqueous medium of an alkyl mercaptan. The resulting clear emulsions are combined with clear polish latexes such as acrylic latexes to form clear polish compositions.

Abstract: Homopolymers and copolymers of vinyl chloride are produced in the form of a powder by a bulk polymerization process which involves a dual temperature operation. Vinyl chloride (either alone or admixed with other copolymerizable monomers) is contacted with conventional polymerization initiators in the absence of solvents or diluents at a first temperature of from about 68.degree. to about 110.degree. F until the polymerization has proceeded to 0.1 to 10% of completion and thereafter the temperature is raised to 120.degree. to 150.degree. F until the polymerization has reached the desired conversion.

Abstract: Copolymers of acrylonitrile and conjugated aromatic olefines, such as styrene, containing 50-95% molar of acrylonitrile are made using an aqueous suspension process in which hydroxyethyl cellulose is used as the suspension agent.

Abstract: Copolymers of acrylonitrile and conjugated aromatic olefines, such as styrene, containing 50-95% molar of acrylonitrile are made using an aqueous suspension process in which polyvinyl pyrrolidone is used as suspension agent.

Abstract: Unique polymers are prepared by the polymerization of high internal phase ratio emulsions of monomers in aqueous systems.

Abstract: In a microsuspension polymerization of vinyl halide monomer additional monomer is added during the polymerization.