Abstract: As an article of manufacture, a microporous flexible shape or sheet of a sulfur-free, cured polymeric material of a curable rubber, an ethylene-propylene copolymer or mixtures of the curable rubber and ethylene-propylene copolymer; the article possesses an average pore size of less than 2 microns, a predetermined flexibility, and improved toughness, when compared to prior art sulfur cured articles.

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.

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: Crosslinked vinylidene chloride polymer microgel powders are recovered from a latex obtained by emulsion polymerizing in sequence (a) a first monomer mixture comprising a predominant amount of vinylidene chloride, an ethylenically unsaturated comonomer, and a crosslinking polyfunctional monomer; (b) a minor amount of a polyfunctional monomer for providing graft sites on the product of (a); and (c) a second monomer mixture which is predominantly acrylonitrile, the amount of the second monomer mixture being in the range of about 10 to 25 percent of the weight of the first monomer mixture. The so-formed microgels, having a particle size less than about 1 micron, are admixed with an acrylic polymer and a suitable solvent and then spun into fibers having improved flame-retardancy.

Abstract: The present invention provides a method for producing curable resin which comprises reacting acrylic acid and/or methacrylic acid [which is hereinafter cited as (metha-) acrylic acid] with hydroxyl group-containing resin (I) obtained by reacting a five-member cyclic compound having an unsaturated conjugated double bond represented by the general formula (A) given below; ##STR1## (WHEREIN R is an organic residue having from 1 to 3 carbon atoms; m and n are integers and are in the relation of m+n=6) or the Diels-Alder addition product thereof (A) and a compound (B) having both reactive carbon-carbon double bond or bonds and towo or more hydroxyl groups within one and the same molecule thereof. In accordance with the present invention, curable coating composition comprising said curable resin can also be obtained. The resin of this invention can be very quickly cured by the exposure to heat or radiation.

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.