Abstract: A block copolymer of propylene can be obtained with its quality controlled uniform by conducting at first continuous polymerization of propylene in a polymerization system, receiving a polymer slurry, which has been discharged continuously from the polymerization system, in a batchwise polymerization tank, feeding ethylene to the tank to conduct batchwise polymerization of ethylene and propylene. Upon discharge of a copolymer slurry formed by the preceding batchwise polymerization, at least a predetermined amount of unreacted ethylene is left over in the tank. Into the tank with the unreacted ethylene still left over therein, there are simultaneously charged the polymer slurry from the polymerization system and a deactivator. During this charging, ethylene is not supplied.

Abstract: A novel block copolymer is disclosed which includes a random ethylene-propylene copolymer segment (A) and a methacrylate segment (B). The block copolymer has a number-average molecular weight of about 1,000 to about 600,000 and a ratio of (A) to (B) of 15/85 to 97/3 by weight.

Abstract: A process for improving the flame retardancy, hygroscopic, soil release and other properties of a polymer substrate is provided in which the substrate is contacted with a suitable aqueous mixture containing a water-soluble monomer and an organic halogen-containing hydrophobic carrier compound at a temperature of between about 40.degree. C. to 100.degree. C. Polymerization of the monomer is thereafter initiated by a chemical or physical initiator to form a polymer evenly disposed on the substrate. The flame retardancy, hygroscopic, soil release and other surface properties of the substrate are thereby improved. The mixture may be in the form of an emulsion wherein the hydrophobic carrier compound is emulsified by an appropriate agent. The invention also pertains to the improved substrates prepared in accordance with the present process.

Abstract: A rubber composition suitable for tire treads having well-balanced excellent steering stability in cornering, wet skid characteristic, ice skid characteristic and rolling characteristic, and an excellent processability, which comprises a rubber component containing a block copolymer consisting essentially of a block A and a block B, obtained by conducting polymerization of an aromatic vinyl compound and a conjugated diene compound in a hydrocarbon solvent in the presence of an organolithium initiator and modifying with a coupling agent, and satisfying the following conditions (A) to (E);(A) the block A having a content of an aromatic vinyl compound of 5 to 29% by weight and a content of 1,2-bonds in the conjugated diene component of 25 to 55% by weight,(B) the block B having a content of an aromatic vinyl compound of 35 to 60% by weight and a content of 1,2-bonds in the conjugated diene component of 20 to 70% by weight,(C) the content of the block A in the block copolymer being from 20 to 80% by weight,(D) th

Abstract: A continuous process as disclosed which produces a clear, high impact block copolymer having a vinyl aryl monomer content of at least 70 percent of the block copolymer. This continuous process involves the continuous preparation of a multiblock copolymer which comprises the alternate feeding of monomer streams to a reaction zone wherein a product stream is withdrawn from the polymerization system at the same rate as the total rate of the feed streams.

Abstract: A thermoplastic resin composition comprising:(A) 20 to 60% by weight of a propylene-ethylene block copolymer obtained by block copolymerizing 70 to 95% by weight, based on the total weight of the block copolymers, of propylene homopolymers obtained by polymerizing propylene at first stage, having a relationship represented by the formula:1.00.gtoreq.P.gtoreq.0.015 log MFR+0.955(wherein P is an isotactic pentad ratio of a propylene homopolymer and MFR is a melt flow rate thereof), and 30 to 5% by weight, based on the total weight of the block copolymer, of ethylene or ethylene and propylene at one or more stages, the ethylene content being 3 to 12% by weight based on the total weight of the block copolymers;(B) 60 to 20% by weight of a styrene homopolymer; and(C) 5 to 30% by weight of a styrene-ethylene.butylene-styrene block copolymer or a styrene-ethylene.propylene block copolymer,the total of (A), (B) and (C) being 100% by weight.

Abstract: A polymerization process for preparing triblock copolymers and multiblock copolymers. The process includes the polymerization of isobutylene below about -40.degree. C. in a reaction mixture which includes a titanium halide, a mixed solvent, and an initiator compound selected from the group consisting of cumyl ester and cumyl ether compounds. In at least some instances, the components are added in a particular order, sometimes together with a moisture scavenger. After formation of the polyisobutylene, a diene is added to the mixture containing the polyisobutylene and polymerized to form the desired copolymer. The diene portion of the copolymer may subsequently be cyclized to produce a copolymer exhibiting both thermoplastic and elastomeric properties. If desired the block copolymers can be subsequently modified to include functional side groups, or to provide photocuring capabilities.

Abstract: A novel block copolymer consisting essentially of ethylene and propylene and comprising 1 to 20 parts by weight of block (A) having an ethylene content of 0 to 4% by weight, 5 to 49 parts by weight of block (B) having an ethylene content of more than 4% and less than 25% by weight, and 50 to 94 parts by weight of block (C) having an ethylene content of 25 to 85% by weight. The block copolymer is characterized by less formation of flow marks in molding, and also has excellent tensile characteristics.

Abstract: An acryl type macromonomer having a polyethyleneimine derivative chain represented by the general formula: ##STR1## where R.sub.1 represents H or CH.sub.3, R.sub.2 represents H or (substituted) alkyl or aryl group, R.sub.3 represents H or (substituted) alkyl group, X represents O or NR.sub.4, R.sub.4 represents H or alkyl or aryl group and n represents an integer from 1 to 1000, or a graft polymer having the polyethyleneimine derivative chain as a graft chain. The macromonomer can be obtained by reacting the compound of the general formula: ##STR2## where R.sub.2 represents H or (substituted) alkyl or aryl group, R.sub.3 represents H or (substituted) alkyl group, Y represents OH or NHR.sub.4, R.sub.

Abstract: A multiphase thermoplastic composition is provided by incorporating at least one polar thermoplastic polymer with at least one functionalized, selectively hydrogenated alkenyl arene/conjugated diene block copolymer to which has been grafted an effective amount of carboxyl functional groups primarily in the alkenyl arene blocks thereof. The carboxyl functional groups may be in the form of carboxylic acids, their salts and esters, and combinations thereof. The rubbery compositions of the present invention possess improved tensile strength, high temperature mechanical properties and oil resistance.

Abstract: A polyalkylene oxide having unsaturated end groups. The polymer has a distribution of molecular weight Mw/Mn of not more than 1.5, and a process for the same. The polymer is useful as rubber materials, and can provide cured rubber having an excellent elongation.

Abstract: The present invention provides a novel epoxy resin-based curable composition suitable for use as an encapsulating resin composition for semiconductor devices capable of being highly resistant against crack formation with low internal stress by curing and yet having very high heat conductivity and maintaining high glass transition temperature. The inventive composition comprises (a) 100 parts by weight of a curable epoxy resin blend which is a mixture of an epoxy resin and a curing agent therefor, (b) from 5 to 100 parts by weight of a block copolymer composed of at least one segment of an aromatic polymeric moiety, phenyl novolac, and at least one segment of an organopolysiloxane moiety having 30 to 200 silicon atoms and bonded to the aromatic polymeric moiety through a carbon-to-silicon linkage, and optionally (c) an inorganic filler which is preferably a silica filler such as powdered quartz in an amount not exceeding 1000 parts by weight.

Abstract: A star-shaped polymer useful as a polymeric VI improver comprising at least one arm which is a block copolymer containing a cunjugated diolefin block and a monoalkenyl aromatic hydrocarbon block and a plurality of arms which are either a homopolymer of a conjugated diolefin or a copolymer of two or more conjugated diolefin or a copolymer of two or more conjugated diolefins. Oil compositions comprising star-shaped VI improvers of this type exhibit relativelylow HTHSR viscosities, and hence, improved fuel efficients when used in automotive applications. Oil compositions comprising star-shaped VI improvers of this type also exhibit improved low temperature pumpability.

Abstract: The present invention relates to a thermally stable modified selectively hydrogenated high 1,2 content block copolymer wherein a functional group is grafted to the block copolymer in the vinylarene block.

Abstract: An improved free radical polymerization process employing as a polymerization initiator a bisquinone peroxide. Upon decomposition to initiate polymerization such bisquinone peroxides may also produce singlet oxygen capable of producing hydroperoxidized rubber if rubber is included in the polymerization mixture. The by-products formed from the decomposition of the bisquinone peroxide desirably comprise hindered phenolic compounds having antioxidant properties.

Abstract: A coating composition for the protection of metallic and non-metallic substrates against corrosion, comprising a film-forming polymer; at least one particulate metallic pigment in an amount ranging from about 30% to about 60% by weight based on the total weight of the composition; an agent for control of electrical conductive characteristics having an oil absorption value of less than 20 (determined by ASTM standard D 281-84), the volumetric ratio of the control agent to the metallic pigment ranging from 0.7:1 to 1.25:1; an agent for control of rheological characteristics; and at least one solvent compatible with the polymer.

Abstract: There is provided a composition having interpenetrating matrices comprising (a) a first polymer network characterized by nodes interconnected by fibrils and (b) a second polymer network comprising diorganosiloxy units. In another aspect, there are provided compositions comprising an interpenetrating polymer network of polytetrafluoroethylene and polydiorganosiloxane. Methods for making the foregoing compositions are also provided.

Abstract: In block copolymers of the general formula A--B--A' which have a molecular weight of less than 300,000 and consist of from 18 to 40% by weight of a vinylaromatic hydrocarbon and from 60 to 82% by weight of one or more partially or completely hydrogenated hydrocarbons and in which A and A' are each a polymer block of a vinylaromatic hydrocarbon and B is a polymer block of a diene hydrocarbon, the weight ratio of the polymer blocks A to A' is less than or equal to 1:5 and greater than 1:10 and the mean molecular weight of polymer block A is from 2,000 to 20,000 and that of the polymer block A' is from 10,000 to 110,000 and the molecular weight of the B block is not less than 18,000.

Abstract: A composition and method for forming the composition providing a molding composition of poly(arylene sulfide) and a crack resistance and/or an impact strength improving amount of a polymeric rubber chosen from among silicone rubber, ethylene-acrylic rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, and poly(butyl acrylate) rubber. In embodiments of the invention the improvement is enhanced by the addition of organosilane to the composition.

Abstract: Novel graft copolymer elastomers comprising a rubbery substrate polymer and a graft copolymer of a monomer capable of grafting to the rubbery substrate and a copolymerizable comonomer having pendant reactive groups capable of functionally reacting with reactive polar functionality of a copolymer of a monovinylidene aromatic monomer and a copolymerizable polar comonomer are disclosed.