Abstract: In the suspension polymerization of styrene monomers in water using suitable suspension stabilizers, the only modifier needed has been found to be organotin compounds in amounts from 10 to 1000 ppm based on monomer. The product beads have a narrow bead size distribution.
Type:
Grant
Filed:
May 21, 1987
Date of Patent:
August 1, 1989
Assignee:
Arco Chemical Technology, Inc.
Inventors:
Bernard H. Meyer, Joseph C. Kinslow, Paul E. Arch, D. Harper Meek
Abstract: A process for the cross-linking of olefin-polymers such as polyethylene which comprises reacting the polymer with a free radical generator to form a polymer having free radicals and reacting the polymer having free radicals with a tetrafunctional organo zirconate which has at least one functional group that is reactive with the free radicals on the polymer followed by contact thereof with moisture or water, optionally in the presence of a condensation reaction catalyst.
Abstract: A linear alternating polymer of carbon monoxide and at least one ethylenically unsaturated hydrocarbon exhibits improved thermal stability as evidenced by reduced weight loss at elevated temperatures and enhanced crystallinity and crystallizability when produced with a catalyst composition formed from preformed palladium trifluoroacetate and a bidentate phosphine ligand.
Abstract: A block copolymer of propylene is produced by using propylene itself as a liquid medium, conducting continuous polymerization (former-stage polymerization) of propylene alone or propylene and a small amount of ethylene at first and then conducting batchwise copolymerization (latter-stage polymerization) of ethylene and propylene. The amount of an activity improver to be added to a polymerization tank for the latter-stage polymerization and/or the polymerization time of the latter-stage polymerization are controlled in accordance with the amount of a slurry transferred from a polymerization tank for the former-stage polymerization to the polymerization tank for the latter-stage polymerization so as to maintain the ratio of the amount of the polymer polymerized by the former-stage polymerization to the amount of the polymer polymerized by the latter-stage polymerization constant in the block copolymer.
Abstract: This invention relates to vinyl monomer compositions exhibiting accelerated surface cure characteristics. These compositions are prepared from a vinyl monomer or monomer mixtures such as a blend of dicyclopentenyloxyethyl methacrylate and hydroxypropyl methacrylate, a bulk phase polymerization catalyst system, a polyvalent metal oxidative surface phase catalyst, and a diolefin rubber dispersed in the vinyl monomer as a surface cure accelerator. These compositions are useful as binders for polymer concrete and as impregnants for porous surfaces. The accelerated surface cure is particularly advantageous with monomer mixtures containing low volatility vinyl monomers.
Abstract: There is disclosed a method for increasing the electrical conductivity of a porous synthetic polymeric material. The method comprises depositing an effective amount of a polyacetylene polymerization catalyst throughout the porous structure, subsequently exposing said material to acetylene under polymerization conditions, for a time sufficient to form polyacetylene within the porous structure, and finally doping the resultant product with a conductivity modifying amount of either an electron donor dopant or an electron acceptor dopant.There is also disclosed an improved electrodialysis process wherein an electrolyte solution is placed between opposite faces of two membranes, the first membrane being an anion exchange membrane and the second membrane being a cation exchange membrane, while being subjected to a primary electric field causing the cations in the electrolyte to pass through the cation exchange membrane and the anions to pass through the anion exchange membrane.
Abstract: New compositions and a process for the preparation of conjugated diene polymers of broadened molecular weight distribution by reacting non-terminated lithium catalyzed conjugated diene polymers with cyclic organic compounds selected from the group of carbonates, thiocarbonates and sulfites. The resulting new compositions are suitable for use in making high impact plastics and for fabricating rubber goods.
Abstract: New compositions and a process for the preparation of conjugated diene polymers of broadened molecular weight distribution by reacting non-terminated lithium catalyzed conjugated diene polymers with linear organic compounds selected from the group of carbonates, thiocarbonates and sulfites. The resulting new compositions are suitable for use in making high impact plastics and for fabricating rubber goods.
Abstract: A novel method for crosslinking a polyolefin comprising reacting a polyolefin, which is a low density polyethylene having a density less than 0.93 and melt index of 0.1-0.5 g/10 min. or a polyolefin mixture containing a low density polyethylene having a density less than 0.93 as major component, with an organic silane and a free radical generating compound to form a silane-grafted polyolefin, then mixing silane-grafted polyolefin with a silanol condensation catalyst, and heating them. According to this method, the crosslinking takes place concurrently with forming by extrusion, and a shaped article having a high degree of crosslinking with smooth surface is obtained. The method according to this invention is especially suited for covering electrical wires with polyolefin.
Type:
Grant
Filed:
June 28, 1979
Date of Patent:
October 14, 1980
Assignee:
The Fujikura Cable Works Ltd.
Inventors:
Ikuo Fujimoto, Setsuya Isshiki, Yoshikazu Kurita, Yoji Sato
Abstract: In the use of certain metal salts of the hemi-perester of maleic acid as catalysts for the polymerization and curing of ethylenically unsaturated monomers and of methyl methacrylate-containing syrups the addition of an activator such as sodium bisulfite provides a substantial reduction in the curing time. The process is relatively insensitive to the amount of filler used. The salts of maleic hemi-peresters, in combination with the activators, are also useful for polymerizing ethylenically unsaturated monomers.
Abstract: A process for production of the maleic anhydride adduct of a liquid polymer having a maleic anhydride addition amount of 2 to 70% by weight, which comprises reacting a liquid polymer having a molecular weight of 150 to 5,000 and a viscosity of 2 to 50,000 cp at 30.degree. C. in the presence of at least one compound, as a gelation inhibitor, selected from the group consisting of imidazoles, thiazoles, metallic salts of mercaptothiazoles, urea derivatives, naphthylamines, nitrosamines, iron, iron compounds and specific halogen compounds, said liquid polymer being selected from the group consisting of liquid polybutadienes, liquid polyisoprenes and liquid copolymers comprising units of butadiene or isoprene and units of at least one compound selected from the group consisting of other diolefins, olefins and aromatic vinyl compounds.