Showing papers on "Copolymer published in 1986"

Uniform polymer particles by dispersion polymerization in alcohol

Abstract: Uniform polystyrene particles in 1–10 μm size range and up to 40% solid contents have been prepared by polymerizing styrene in ethyl alcohol with azo-type initiators and a polymeric stabilizer polyvinylpyrrolidone along with an anionic, nonionic, or comonomeric co-stabilizer. Effects of polymerization parameters, such as monomer concentration, type of co-stabilizer, initiator type and concentration, crosslinking monomer, and diluent on average particle size and size distribution have been studied. Functional groups such as hydroxyl, carboxyl, amine, amide, silane, polydimethylsiloxane, and silacrown have been successfully incorporated onto the particles by copolymerization. A mechanism for particle formation and growth in dispersion polymerization is presented.

Theory of Microphase Separation in Graft and Star Copolymers

Abstract: Calcul des criteres de stabilite de phase et de facteurs de structure statique pour des copolymeres AB simples greffes, pour des copolymeres etoile avec un nombre eg-l de bras A et B et pour des copolymeres bisequences, en etoile a n-bras

Stable tetrafluoroethylene copolymers

Abstract: A tetrafluoroethylene/perfluoro(alkyl vinyl)ether copolymer substantially free of unstable end groups and extractable fluoride that cause corrosion of metal surfaces.

Effect of arm number and arm molecular weight on the solid-state morphology of poly(styrene-isoprene) star block copolymers

Abstract: Caracteristiques morphologiques examinees par microscopie electronique, diffusion RX aux petits angles, analyse thermique mecanique dynamique et sorption de vapeur

New supported polymerization catalyst

Abstract: An olefin polymerization supported catalyst comprising the supported reaction product of at least one metallocene of a metal of Group IVB, VB, and VIB of the Periodic Table, a non-metallocene transition metal containing compound of a Group IBV, VB, or VIB metal and an alumoxane, said reaction product formed in the presence of the support. The supported product is highly useful for the polymerization of olefins especially ethylene and especially for the copolymerization of ethylene and other mono and diolefins.

Molecular design of multicomponent polymer systems, 13. Control of the morphology of polyethylene/polystyrene blends by block copolymers

Abstract: As investigated by optical and electron microscopy, the observed morphology of the meltblended polyethylene/polystyrene pair unambiguously supports the interfacial activity of poly(hydrogenated butadiene-b-styrene) copolymers. The phase size is significantly reduced, the interfacial adhesion is dramatically increased and the phase dispersion is firmly stabilized against coalescence during subsequent processing. Diblock copolymers with a balanced composition are the most efficient interfacial agents in such an extent that only small amounts (1–2 wt.-%) are required to obtain homogeneous and stable phase dispersions. The emulsification concept applied to melt-blended immiscible polymers appears to be a powerful technique to prepare valuable polymer alloys.

Apparatus for the continuous production of polymers and copolymers of water-soluble monomers

Abstract: The present invention relates to a process and an apparatus for the continuous production of polymers and copolymers of water-soluble monomers particularly arcylic acid and/or methacrylic acid, optionally with additional comonomers, by the polymerization of an aqueous monomer solution that is introduced into the trough that is formed by an endless conveyor belt. The trough-like shape of the conveyor belt changes continuously into an extended flat profile during the polymerization process; starting from the side edges and working towards the center of the trough formed by the conveyor belt, the resulting polymer gel strand is released continuously during the transition of the curved trough-like shape of the conveyor belt into the extended, flat form.

Copolymerization of ω-Unsaturated Oligo(Methyl Methacrylate): New Macromonomers

Abstract: The free-radical copolymerization of ω-unsaturated oligo(methyl methacrylate) (1) with each of ethyl acrylate, styrene, methyl methacrylate, acrylonitrile, and vinyl acetate have been investigated. Incorporation of (1) into the polymer was observed in all cases although the molecular weights of the copolymers were substantially lower than those of the homopolymers obtained in the absence of (1) but under otherwise identical conditions. These experiments, together with a product study of the reactions of (1) with cyanoisopropyl radicals, have shown that the addition of free radicals to the double bond of (1) occurs readily. The sterically hindered radical so formed, however, undergoes facile β-scission, resulting in the termination of chains (chain transfer) in competition with chain propagation. The implications of these findings to the usefulness of (1) in the synthesis of graft copolymers and their relevance to the chemistry of free-radical polymerizations when methyl methacrylate is employed a...

Random copolymer and process for production thereof

Abstract: A random copolymer characterized in that (A) the copolymer comprises polymerized units from ethylene and polymerized units from at least one cycloolefin, (B) the mole ratio of the polymerized units from the cycloolefin to the polymerized units from ethylene is from 3:97 to 60:40, (C) the cycloolefin is incorporated in the polymer chain without ring opening, (D) the copolymer has an intrinsic viscosity of 0.01 to 20 dl/g, (E) the copolymer has a molecular weight distribution (Mw/Mn) of not more than 4, and (F) the copolymer has a crystallinity of 0 to 10%. The random copolymer may be grafted by (a) alpha, beta-unsaturated carboxylic acids and/or their derivatives, (b) styrenes, (c) organic silicon compounds having an olefinically unsaturated bond and a hydrolyzable group, or (d) unsaturated epoxy monomers. The random copolymer is produced by continuously copolymerizing ethylene with at least one cycloolefin in a hydrocrbon medium in the presence of a catalyst formed from a soluble vanadium compound and an organoaluminum compound while maintaining the atomic ratio of vanadium atoms to aluminum atoms in the reaction system, V/Al, at 2 or higher.

Styrene-diene block copolymer compositions

Abstract: This invention comprises to styrene-diene block copolymer-oil-coupling agent compositions which are radiation cross-linked. In another aspect this invention relates to similar composition wherein the styrene-diene block copolymer is a blend of two different poly(styrene-ethylenebutylene-styrene) triblock copolymers, which composition may also be radiation cross-linked.

Propylene polymer composition

Abstract: PROPYLENE POLYMER COMPOSITION ABSTRACT OF THE DISCLOSURE A propylene polymer composition comprising (A) a modified propylene polymer obtained by treating: (1) 100 parts by weight of a propylene polymer or a mixture of a propylene homopolymer and a ethylene-propylene copolymer rubber, with (2) 0.1 to 50 parts by weight of an organic compound having at least one unsaturated bond in the molecule and a hydroxyl group and (3) 0.01 to 20 parts by weight of an organic peroxide; and (B) a propylene polymer, wherein content of the component (A) in the composition is 5 to 50% by weight. This composi-tion may further contain one or more of (C) an amorphous ethylene-propylene copolymer having a propylene content of 20% to 50% by weight and a Mooney viscosity ML1+4 at 100°C of 20 to 100, (D) a high-density ethylene copolymer having a density of 0.935 g/cm3 or more, (E) a linear low-density ethylene copolymer having a density of not less than 0.900 g/cm3 but less than 0.935 g/cm2, a melting point of 106°C to 130°C, a melt flow rate of 0.01 to 100 g/10 min. and substantially having 3 to 35, based on 1,000 carbon atoms of the backbone carbon chain, of the side-chain alkyl groups having 1 to 10 carbon atoms, and (F) an inorganic filler. The resultant composition has not only an excellent adhesion to polyurethane without the use of a primer, but also has a good weathering resistance.

Cobalt(II) chelates as chain transfer agents in free radical polymerizations

Abstract: Free radical polymerization processes employing cobalt(II) chelates of vicinal iminohydroxyimino compounds, diazadihydroxyiminodialkyldecadienes and -undecadienes, tetraazatetraalkylcyclotetradecatetraenes and -dodecatetraenes, N,N'-bis(salicylidene)ethylenediamines and dialkyldiazadioxodialkyldodecadienes and -tridecadienes as catalytic chain transfer agents for controlling the molecular weight of the homopolymers and copolymers produced.

Encapsulated solar cell assemblage and method of making

Abstract: A solar cell assemblage and method of making, comprising: (a) a pre-treated silanized transparent substrate; (b) a layer of semiconductor material; (c) an electrical contact on the surface of said layer of semiconductor material; (d) an extruded transparent film encapsulating the assemblage which comprises 75 to 91 parts by weight of a blend of: 65 to 75 parts by weight of a selectively hydrogenated two-block polymer wherein (1) each A is a polymer block of a monovinyl or alpha alkyl monovinyl arene and the A blocks are from 10 to 40% by weight of the total block copolymer, and (2) each B is a polymer block formed by polymerizing a conjugated diene, and the B blocks are 90 to 60% weight of the total block copolymer, and 25 to 35 parts by weight of a selectively hydrogenated multiblock copolymer wherein: (1) each A is a polymer endblock of a monovinyl or alpha alkyl monovinyl arene and the A blocks are 10 to 40% by weight of the total block copolymer, and (2) each B is a polymer midblock is formed by polymerizing a conjugated diene and the B blocks are 90 to 10% weight of the total block copolymer, about 8.5 to about 23.5 parts by weight of an (alpha) methyl styrene polymer tackifying resin; and about 0.5 to about 1.5 parts by weight of a mixture of a phenolic antioxidant, a UV absorber with benzotriazole functionality and a UV absorber with hindered amine functionality; (e) a carbon filled polymer frame; and (f) sealant.

Liquid ethylene-alpha-olefin random copolymer, process for production thereof, and use thereof

Abstract: A liquid ethylene-alpha-olefin random copolymer, characterized in that (a) it has an ethylene unit content of 10 to 85 mole % and an alpha-olefin unit content of 15 to 90 mole %, (b) it has a low molecular weight, (c) it has a narrow molecular weight distribution, (d) the dispersion of the ethylene units and alpha-olefin units in the polymer chain is in the advanced state, and (e) the directions of bonding of the alpha-olefin units in the polymer chain are nearly the same. The copolymer is prepared by copolymerizing ethylene and an alpha-olefin having 3 to 20 carbon atoms in the presence of a catalyst comprising a compound of a transition metal of Group IVb of the periodic table and an aluminoxane. The copolymer is very useful as a synthetic lubricant oil.

Molecular design of multicomponent polymer systems. XII. Direct observation of the location of a block copolymer in low‐density polyethylene‐polystyrene blends

Abstract: Modification d'un copolymere butadiene hydrogene-styrene par insertion d'une courte sequence centrale isoprene, permettant de localiser le copolymere a l'interface du melange fondu d'homopolymeres

Thermoplastic elastomer composition

Abstract: A thermoplastic elastomer composition and process comprising a crystalline polyolefin, halogenated butyl rubber, olefin copolymer rubber, polyolefin modified with, e.g., maleic anhydride and optionally nitrile rubber, wherein the halogenated butyl rubber isat least partially crosslinked using a metal oxide and/or chloride, e.g., zinc oxide. Crosslinking is achieved under dynamic mixing conditions and the resulting composition has superior strength,performance and processing properties. Furthermore, use of nitrile rubber imparts improved oil resistance to the composition.

Rubber-modified nylon composition

Abstract: A polyamide composition of improved impact resistance comprising a blend of components (A) a core/shell graft rubber composition having a thermoplastic copolymer shell comprising a polyamide-interactive monomer, (B) a polyamide and, (C) an acid-containing acrylate copolymer rubber.

Hydrogenated block copolymer compositions

Abstract: A composition having a composition containing substantially no other engineering thermoplastic resin and a compression set (JIS K 6301; 100° C.×22 hours; and compressibility, 25%) of 65% or less as rubber which comprises: (a) 100 parts by weight of a hydrogenated block copolymer obtained by hydrogenating a block copolymer comprising at least two polymer blocks A composed mainly of a vinyl-substituted aromatic hydrocarbon and at least one polymer block B composed mainly of a conjugated diene, (b) 11 to 233 parts by weight of a homopolymeric and/or copolymeric polyphenylene ether resin comprising a binding unit represented by the general formula, ##STR1## wherein R1, R2, R3 and R4, which may be the same or different, represent substituents selected from the group consisting of hydrogen, halogen, hydrocarbon groups and substituted hydrocarbon groups, and having a reduced viscosity in a range of from 0.15 to 0.70 as measured at 30° C. in a 0.5 g/dl chloroform solution, (c) 10 to 500 parts by weight of a non-aromatic softening agent for rubber, and (d) 5 to 150 parts by weight of a polyolefin resin and/or a polystyrene resin.

Polymerization using palladium (II) salts: Homopolymers and copolymers from phenylethynyl compounds and aromatic bromides

Abstract: Preparation d'homopolymeres de faibles masses moleculaires du m-bromophenylacetylene ainsi que de copolymeres et reseaux de benzenes di- et triethynyl avec des di- et tribromobenzenes par une reaction de couplage utilisant un sel de Pd(II), la triphenylphosphine et l'iodure cuivreux comme catalyseur

Adhesive copolymer microspheres-containing aqueous suspension and method for producing the same

Abstract: A repeatedly usable and releasable sheet is coated thereon with an adhesive copolymer microspheres-containing aqueous suspension and polymer microparticles prepared by polymerization of one or more vinyl monomers. In the presence of a protective colloid comprising casein, the microspheres is prepared by aqueous suspension polymerization of (a) from 70 to 99.9 percent by weight of one or more monomers selected from the group consisting of alkyl acrylate esters and alkyl methacrylate esters, (b) from 0.1 to 10 percent by weight of one or more α-monoolefin carboxylic acids and (c) from 0 to 29.9 percent by weight of one or more vinyl monomers other than the foregoing (a) and (b).

Miniemulsion copolymerization of vinyl acetate and butyl acrylate. I: Differences between the miniemulsion copolymerization and the emulsion copolymerization processes

Abstract: Differences between the emulsion copolymerization and miniemulsion copolymerization processes, in terms of emulsifier adsorption, emulsion stability, polymerization kinetics, copolymer composition and dynamic mechanical properties were studied for the comonomer mixture of 50:50 molar ratio vinyl acetate (VA+)—butyl acrylate (BuA), using sodium hexadecyl sulfate (SHS) as a surfactant and hexadecane (HD) as a co-surfactant. The use of hexadecane with the appropriate SHS initial concentration led to a higher adsorption of surfactant, smaller droplet size, higher stability of the emulsions, lower polymerization rates, and larger latex particle size. The copolymer composition during the initial 70% conversion was found to be less rich in Vac monomer units for the miniemulsion process. The dynamic mechanical properties of the copolymer films showed less mixing between the BuA-rich core and the VAc-rich shell in the miniemulsion latexes compared to the conventional latex films.

Pressure-sensitive adhesive composition

Abstract: A pressure-sensitive adhesive composition comprising as a base polymer a mixed block copolymer comprising a polymer block of a monovinyl-substituted aromatic compound and a polymer block of a conjugated diene compound. The pressure-sensitive adhesive composition is useful to seal, for example, corrugated board or carton.

Surgical suture coating

Abstract: A surgical suture coating comprising a random copolymer is disclosed. The copolymer has about 25 to 75 weight percent of glycolic acid ester linkages. The remaining linkages comprise at least trimethylene carbonate. The copolymer has a glass transition temperature at or below ambient temperature.

Kinetic modeling of copolymerization/crosslinking reactions

Abstract: Copolymerisation radicalaire monomere monovinyl-divinyl. Information cinetique de l'amorcage, propagation et reticulation, terminaison et transfert de chaine. Application au systeme styrene/(p) m-divinyl-benzene

Copolymers and their use

Abstract: The molecular weight and/or flocculation or coagulation efficiency of polymers of diallyl monomers such as DADMAC can be increased by copolymerising the monomers with an amide monomer such as MAPTAC.

Copolymerization of cationic monomers with acrylamide in an aqueous solution

Abstract: Rapports de reactivite obtenus pour 7 types de monomeres cationiques commerciaux; calcul des parametres Q et C et relation entre Q et les maxima d'absorption UV des monomeres

Polymeric compositions comprising olefin polymer and nitrogen containing ester of a carboxy interpolymer

Abstract: Polymeric compositions are described which comprise a mixture of (A) at least one oil-soluble polymer which is a homopolymer of a non-aromatic monoolefin or a copolymer of said non-aromatic monoolefin with an aromatic monoolefin, and (B-1) at least one nitrogen-containing ester of a carboxy-containing interpolymer, and/or (B-2) at least one oil-soluble acrylate polymerization product of at least one acrylate ester, or a mixture of one or more of (B-1) and (B-2). The polymeric compositions of the invention also may contain (C) an effective amount of at least one viscosity-reducing liquid organic diluent such as a naphthenic oil or an alkylated aromatic material. Polymeric compositions of the present invention are useful as additives in transmission fluids (both automatic and manual) and hydraulic fluids, and the transmission fluids and hydraulic fluids containing the polymeric compositions of the present invention exhibit improved shear stability while maintaining desired high and low temperature viscosity characteristics.