Abstract: High impact polystyrene having excellent properties is produced by a continuous process comprising feeding rubber and styrene continuously to a multistage horizontal dissolving tank to dissolve the rubber completely with stirring by increasing the temperature of each stage stepwise along the liquid flow direction, feeding the rubber solution to a first polymerizer to effect phase inversion of the rubber and preliminary polymerization of styrene; feeding the pre-polymerized solution to one or more horizontal type polymerizers to undergo bulk polymerization while removing the heat generated therein; and feeding the polymerized solution to a monomer separator to remove the remaining monomer.

Abstract: A process for the production of cross-linked graft copolymers by the radically initiated precipitation copolymerization of an ethylene/vinyl ester copolymer as graft base and a mixture to be grafted of one or more aromatic monovinyl compounds, acrylonitrile and/or methacrylonitrile, a cross-linking agent containing two or more carbon-carbon double bonds, and, optionally, another monoolefinically unsatured copolymerizable monomer wherein the ungrafted base is precipitated by the addition of a precipitating agent simultaneously with the precipitating cross-linked graft copolymer.

Abstract: In a process for the mass polymerization of vinyl aromatic monomer wherein vinyl aromatic monomer is polymerized in successive stages of increasing temperature, the improvement which narrows the molecular weight distribution of the resulting polymer comprising incorporating a crosslinking agent into a polymerizing mass at a point where about 60 to about 95% of monomer is converted to polymer.

Abstract: The invention relates to polymers and copolymers of pivaloyloxyalkyl methacrylates which contain structural units of the general formula ##STR1## where R.sup.1 is (CH.sub.2).sub.n.sbsb.1 --O (n.sub.1 =2 to 10) or (CH.sub.2 CH.sub.2 --O).sub.n.sbsb.2 (n.sub.2 =1 to 4) and to the method of their preparation and modification. The polymerization and copolymerization can be initiated by free-radical initiators of the peroxy type or by anionic initiators, e.g., alkali metal alkoxides or butyllithium, and carried out in a solution, bulk or suspension process in the presence of a crosslinking agent or without it. Anionic polymerization may result in stereoregular polymers or may be used for preparation of block copolymers by the "living" polymer technique. The polymers and copolymers can be modified by the partial or total conversion of the pivaloyloxyalkyl methacrylate units into hydroxyalkyl methacrylate units by selective hydrolysis, alcoholysis or other reaction.

Abstract: There is disclosed an environmentally degradable plastic composition comprising an organic polymeric material having dispersed therein at least one ethylenically unsaturated alcohol or ethylenically unsaturated ester derived therefrom as a readily autoxidizable organic substance.

Abstract: An aqueous dispersion of an olefinic resin composition having improved properties which comprises mixing an olefinic resin composition comprising (a) 50 to 99% by weight of a carboxyl-free olefinic resin having an intrinsic viscosity of 0.1 to 5 and (b) 1 to 50% by weight of a carboxyl-containing modified olefinic resin having an intrinsic viscosity of 0.04 to 1 and an acid number of 30 to 150, the amount of each resin being based on the total amount of resins (a) and (b), which has been melted by heating to a temperature above the melting point, whichever is higher, of the resins, with an aqueous medium heated to a temperature of 140 to 300.degree. C. in the presence of at least 0.2 chemical equivalent, to the carboxyl groups of resin (b), of a base.

Abstract: The production of polymer beads by a suspension polymerization process in which a vinyl aromatic monomer having a free-radical generating catalyst dissolved therein is suspended in an aqueous medium with the aid of from 0.1 to 2.0 percent by weight, based on monomer, of a finely divided phosphate suspending agent in the presence of a modifier and heated to cause the monomer to polymerize into polymer beads is improved by the addition to the suspension of at least about 0.01 percent by weight based on monomer of an adjunct modifier, such as certain aminoalkanecarboxylic acids and N-substituted derivatives thereof. The process of the invention is especially applicable in the preparation of large polymer beads.

Abstract: Process for the preparation of a transparent, weather-resistant vinyl chloride polymer having a very high impact strength by the polymerization of vinyl chloride either together with or without other copolymerizable monomers in aqueous dispersion by the emulsion polymerization method in the presence of at least one acrylic ester copolymer. The process involves emulsion polymerizing vinyl chloride or a monomer mixture containing at least 80 percent by weight of vinyl chloride in the presence of a dispersion of at least one acrylic ester copolymer consisting of 90 to 99.7 percent by weight of at least one acrylic ester containing 3 to 16 carbon atoms in the ester group and 0.3 to 10 percent by weight of a polyfunctional monomer having at least two non-conjugated ethylenic double bonds, at least one of said double bonds being of the allyl type. The acrylic ester copolymer having a mean particle diameter of 30 to 150 nm, determined by soap titration.