Abstract: This invention relates to a polychloroprene elastomer distinguished by good processing properties and high tensile strength in the form of a polychloroprene mixture containing a sol polymer and a gel polymer in a ratio, by weight, of from 1:4 to 9:1, characterized in that both polymers have been produced in the presence of from 2.5 to 4.0 parts, by weight, of the potassium salt of disproportionated abietic acid (expressed as acid), from 0.3 to 1.0 part, by weight, of a condensation product of naphthalene sulphonic acid and formaldehyde and from 0.1 to 1.5 parts, by weight, of potassium hydroxide, based in each case on 100 parts, by weight, of monomer, and in that the gel polymer is a copolymer of chloroprene and from 1.5 to 2.5 mole percent, based on total monomer, of a diester corresponding to the following general formula: ##STR1## wherein R.sub.1 and R.sub.2 represent hydrogen, chlorine or C.sub.1 -C.sub.4 alkyl; andX represents C.sub.2 -C.sub.10 alkylene.

Abstract: Precrosslinked nitrile rubber polymers are prepared by interpolymerizing a polyol polyacrylate with butadiene and acrylonitrile to improve compression set, extrusion rate and die swell properties of the precrosslinked polymers and blends thereof with linear nitrile rubber polymers without sacrificing other physical and processing properties.

Abstract: Compositions hardenable by exposure to heat or electromagnetic radiation are provided by blending from about 0% to about 50% by weight of an uncrosslinked polymer, from about 20% to about 66% of a polymerizable monomer capable of dissolving said polymer, from about 10% to about 70% of a crosslinked polymer in the form of discrete particles having average diameters of from 0.001 micron to about 500 microns and being swellable by said monomer, and from about 0.25% to about 27% of a crosslinking agent for said monomer. Such compositions exhibit superior chemical and physical characteristics when hardened and are suitable in a wide variety of applications as construction media. In accordance with a preferred form of the invention, a precursor blend is formed from a mixture comprising (A) from 13 to 52 weight percent of a crosslinked polymer of an ester of a C.sub.1 -C.sub.6 alkyl acrylic acid and a C.sub.1 -C.sub.

Abstract: Cyanacrylic acid ester based glues with a reduced setting time comprising a cyanacrylic acid ester and from 0.005% to 3% by weight, based on the cyanacrylic acid ester of a polyoxyalkylene glycol diester having the formula ##STR1## wherein x is an integer from 5 to 80, Alk is an alkylene having from 2 to 4 carbon atoms, and R.sub.1 and R.sub.2 represent members selected from the group consisting of hydroxyl, halogen, lower alkoxy, alkoxyalkyl having from 3 to 12 carbon atoms, alkyl having from 1 to 12 carbon atoms, cyanoalkyl having from 1 to 12 carbon atoms, haloalkyl having from 1 to 12 carbon atoms, nitroalkyl having from 1 to 12 carbon atoms, alkenyl having from 2 to 12 carbon atoms, alkynyl having from 2 to 12 carbon atoms, cycloalkyl having from 3 to 12 carbon atoms, phenyl, nitrophenyl, halophenyl, phenylalkyl having from 1 to 6 carbon atoms in the alkyl and alkylphenyl having from 1 to 6 carbon atoms in the alkyl.

Abstract: The invention includes dental materials based on organic plastics in paste form, comprising at least one phase consisting essentially of finely divided, crosslinked plastics which contain copolymerized ester(s) of methacrylic acid to the extent of at least 50% by weight, and the second phase consisting essentially of ester(s) of methacrylic acid to the extent of at least 50% by weight. The materials can be used for making prostheses, crowns, bridges, artificial teeth, dental fillings, etc.

Abstract: Sag-resistant, pumpable compositions are described which comprise a liquid material dispersed throughout a cross-linked polymer matrix. The liquid material may be a polymerizable material or a polymer-containing material. The compositions of the invention have very broad utility, depending upon the particular ingredients present.

Abstract: A dental material is provided based on organic plastics in paste form, which consists essentially of (a) a polymerizable binder, (b) a crosslinked bead polymer and (c) a fine-particled inorganic filler.

Abstract: The invention provides dental materials which are opaque to X-rays and are based on organic plastics in paste form, which comprises (a) a polymerizable binder, (b) a crosslinked bead polymer and (c) an X-ray contrast medium. The materials can also contain as an additional component (d) a fine-particled inorganic filler which is not opaque to X-rays. The materials are useful, inter alia, for filing dental cavities.

Abstract: Flame retardation of 1,2-polybutadiene based upon the use of halogenated bisphenol bisacrylate reactive flame retardants, for example, 2,2-bis(4-methacryloyl-3,5-dibromophenyl)-propane. Flame retardancy performance of UL 94 V-0 or V-1 has been achieved without impairing desirable dielectric properties and heat resistance inherently possessed by 1,2-polybutadiene. If an aromatic bismaleimide modifier, for example, N,N'-4,4'-diphenylmethane bismaleimide, is jointly used, a thermal expansion coefficient less than a half of the thermal expansion coefficient of cured 1,2-polybutadiene can be achieved.

Abstract: Sag-resistant, pumpable compositions are described which comprise a liquid material dispersed throughout a crosslinked polymer matrix. The liquid material may be a polymerizable material or a polymer-containing material. The compositions of the invention have very broad utility, depending upon the particular ingredients present.

Abstract: Impact modified polyvinyl chloride is prepared by suspension polymerizing vinyl chloride in the presence of a dual catalyst system of a monomer soluble catalyst and a water soluble catalyst to form suspension polymer particles having irregular and porous surfaces, and then polymerizing, in the presence of the porous particles, monomers for forming gelled rubber-containing interpolymer particles having a Tg of less than 25.degree. C. No emulsification system is required for the rubber interpolymerization. Rubber-containing interpolymer particles in the order of 1 micron or less are formed on the surface of the suspension polyvinyl chloride particle. The process can be conducted in one reaction vessel and product contamination is reduced. The product can be used alone or blended with other thermoplastic polymers, such as polyvinyl chloride, to increase the impact strength thereof.

Abstract: Elemental sulfur modified polychloroprene rubbers having improved Mooney viscosity stability are prepared by blending a sol and a gel in a weight ratio of sol:gel of from 98:2 to 60:40 based on solids, wherein the gel contains 0.5 to 5 weight percent of a cross-linking agent comonomer, a trihydric ester of the general formula ##STR1## wherein x is 0 or an integer of from 1 to 4 and is preferably 0; y is 0 or an integer of from 1 to 4 and preferably 1; R.sub.1, R.sub.2 and R.sub.3 represent hydrogen or an alkyl radical with from 1 to 4 carbon atoms and is preferably CH.sub.3.