Abstract: Disclosed are crosslinking compositions having both sulfur and nonsulfur curative systems which are particularly adapted for crosslinking rubber blends of (a) from about 35% to about 85% halobutyl rubber or a mixture of butyl rubber and halobutyl rubber wherein the halobutyl rubber is at least 50% by weight of the mixture and (b) from about 15% to about 65% of an epihalohydrin rubber, and to the rubber materials crosslinked therewith. The rubber materials crosslinked with these crosslinking compositions have an excellent balance of cure rate, cure state and scorch safety; have improved tire carcass adhesion and good impermeability to gases; and are useful in tire inner tubes and inner liners.

Abstract: A method for easily, inexpensively and efficiently producing an improved water-absorbent resin having a high water absorbency and a high water absorption rate and capable of forming a gel having a high gel strength and nonstickiness, in which water-absorbent resin particles which contain water and a crosslinking agent and are in the semi-swollen state are agitated at an elevated temperature in the presence of an inert inorganic powder to conduct the crosslinking of the resin, while removing water, the water-absorbent resin containing a monomer units having a carboxyl group in the form of free acid or a metal salt.

Abstract: A curable fluoropolymer composition containing a copolymer of vinylidene fluoride and hexafluoropropylene or the like, a vulcanization accelerator which is a quaternary ammonium compound or a quaternary phosphonium compound, a crosslinking agent such as a bisphenol, a divalent metal oxide or divalent metal hydroxide acid acceptor, and as a coaccelerator a polyol e.g. pentaerythritol or the like.

Abstract: A process is provided for the production of a mixture of butadiene-acrylonitrile polymer and zinc peroxide which comprises (i) reacting an agitated aqueous mixture of French Process zinc oxide, sulphuric acid and hydrogen peroxide to form an aqueous slurry of a mixture of zinc peroxide and zinc oxide, and (ii) mixing with said slurry a latex of a butadiene-acrylonitrile polymer, followed by coagulating the mixture and recovering and drying the product.

Abstract: Advantages in the dressing of leather, especially of split leather, with a synthetic rubber latex are obtained if in the leather dressing, the rubber latex is reacted with from 0.5 to 50% by weight, based on solid rubber, of one or more oxides and/or hydroxides of one or more bivalent metals and the leather is treated with a non-polymerized rubber latex which is produced in a one-stage process up to a monomer conversion of from 70 to 95% by weight, by emulsion polymerization of:(A) from 1 to 10 parts by weight of one or more .alpha.,.beta.-monoethylenically unsaturated carboxylic acids; and(B) from 90 to 99 parts by weight of a mixture of(a) from 10 to 90 parts by weight of butadiene and(b) from 10 to 90 parts by weight of styrene and/or acrylonitrile, wherein the quantity of acrylonitrile in the mixture amounts to a maximum of 50 parts by weight.

Abstract: Ionic hydrocarbon polymers having improved adhesion to nylon are provided comprising copolymers of .alpha.-olefins and alpha,beta-ethylenically unsaturated monocarboxylic acids and optionally other monoethylenically unsaturated monomers wherein from about 10 to 90 percent of the carboxylic acid groups are ionized by neutralization with zinc ions uniformly distributed throughout the copolymer such that the resultant ionic copolymer has a zinc salt content of from about 0.0115 to about 0.0229 mols per 100 grams of ionic copolymer. Such ionic copolymers are particularly suitable to be coextruded with nylon as a result of their improved adhesion thereto.

Abstract: A liquid chloroprene polymer having substantially at least one carboxyl group in the molecule and having a number average molecular weight of about 500 to about 20,000 which is produced by(1) homopolymerizing a chloroprene monomer or(2) copolymerizing a chloroprene monomer with a monomer copolymerizable with a chloroprene monomer,in the presence of an organic solvent and about 0.5 to about 20 parts by weight of a mercaptocarboxylic acid per 100 parts by weight of the monomers. The liquid polymer is reacted with a polyvalent metal oxide or hydroxide to form a thermo-reversible elastomeric composition.

Abstract: This invention is directed to a composition for use as a material for the outer layer of a golf ball, which composition is produced by the reaction of an ionomer resin with a monoepoxy compound. The golf ball having the outer layer of such composition can be driven for a long distance with a soft shot feeling.

Abstract: Copolymers of vinylidene fluoride with at least one other fluorinated- ethylenically unsaturated monomer are press-cured at about 163.degree.-204.degree. C. by crosslinking with an aromatic polyhydroxy compound in the presence of an accelerator in a weakly basic system, at least a portion of the polyhydroxy compound being blocked by conversion to acetal or thioacetal groups. At the press-cure temperature some of the acetal or thioacetal groups are decomposed and the free hydroxyl groups are reformed, thus providing crosslinking capability. The remainder of acetal or thioacetal groups are decomposed during post-cure oven heating at a higher temperature, and under those conditions copolymer vulcanization is completed. Press-cured compositions of this invention have excellent hot tensile elongation, which permits easy demoldability; and very good recyclability, which eliminates or reduces fluoropolymer waste. The compositions of this invention also have excellent mold flow properties at press-cure temperature.

Abstract: A process for vulcanizing a rubber base comprising at least one halogen-containing amorphous polymer at a low temperature ranging from 5.degree. to 85.degree. C., which comprises carrying out the vulcanization in the presence of 0.01 to 20 parts by weight of an organic hydroperoxide and/or ketone peroxide per 100 parts by weight of the rubber base.In the above process, at least one member selected from the group consisting of (I) the oxides of metals, such as zinc, lead, chromium, cobalt, nickel, magnesium, manganese, copper and iron, or the metallic salts of said metals with aliphatic or cycloaliphatic carboxylic acid having 8 to 24 carbon atoms; (II) methacrylic esters; (III) maleimides; and (IV) oximes, may be used as a vulcanization activator or a vulcanization accelerator in an amount of 0.01 to 20 parts by weight per 100 parts by weight of the rubber base.