Abstract: Provided are a preparation process of a copolymer for semiconductor lithography, suited for a film forming composition used for the formation of minute patterns necessary for semiconductor fabrication, which comprises carrying out radical polymerization of at least two monomers having an ethylenic double bond in the presence of a polymerization initiator in a polymerization solvent, while causing to exist, in the solution containing the monomers, a polymerization inhibitive component; and a copolymer for semiconductor lithography prepared by the above-described process, and contains no high polymer, has excellent storage stability and generates remarkably less defects in resist pattern when used for semiconductor lithography.

Abstract: A metallocene catalyst may be temporarily and reversibly passivated by contact with an effective amount of a passivating compound selected from the group of oxygen, oxygen-containing compounds, and nitrogen-containing compounds.

Abstract: A diene rubber (A) having a weight average molecular weight (Mw) of 100,000 to 3,000,000, an Mw/number average molecular weight (Mn) ratio of 1.30 to 2.50, and an Mw/peak top molecular weight (Mp) ratio 0.70 to 1.30. A rubber composition comprising the diene rubber (A) and a diene rubber (B) having an Mw of 2,000 to 90,0000 and/or an oil extender for rubber has good processability and can give a rubber vulcanizate having high tensile strength and good abrasion resistance. The diene rubber (A) is produced by conducting a living polymerization of diene monomer in a hydrocarbon solvent; adding a polymerization stopper to a polymerization mixture at a conversion of 5 to 98% to deactivate 10 to 90% by mole of active terminals present as of the initiation of polymerization; and finally adding a polymerization stopper to completely terminate the polymerization reaction.

Abstract: Processes for transitioning among polymerization catalyst systems, preferably catalyst systems that are incompatible with each other. In particular, the processes relate to transitioning from olefin polymerizations utilizing metallocene catalyst systems to olefin polymerizations utilizing traditional Ziegler-Natta catalyst systems.

Abstract: Continuous gas-phase polymerization process for preparing ethylene and propene homopolymers and copolymers, in which ethylene, propene or mixtures comprising ethylene or propene and C3-C8-?-monoolefins are polymerized in the polymerization zone of a gas-phase polymerization reactor at from 30 to 125° C. and pressures of from 1 to 100 bar in the gas phase in a bed comprising finely divided polymer in the presence of a catalyst. To remove the heat of polymerization, the reactor gas is circulated and firstly passes through a cyclone after leaving the reactor. To prevent polymer deposits in the circulating gas system, a catalyst poison having a boiling point above the maximum temperature within the circulating gas system is fed into this circulating gas system at a position between the reactor and the cyclone.

Abstract: A polymer scale preventive agent for use in the polymerization of a monomer containing an ethylenic double bond is provided. The agent includes (A) a condensation reaction product obtained by reacting an aldehyde compound and a hydroxynaphthalene-based compound in the presence of a reducing agent, and (B) a polymer compound containing a nitrogen atom. This agent is capable of forming a coating with satisfactory scale prevention properties on inner wall surfaces of a polymerization vessel with a single-stage application, enabling the production process time to be shortened and the productivity and quality of polymeric products improved.

Abstract: Processes for transitioning among polymerization catalyst systems, preferably catalyst systems that are incompatible with each other. In particular, the processes relate to transitioning among olefin polymerization reactions utilizing Ziegler-Natta catalyst systems, metallocene catalyst systems and other MAO-based single site catalyst systems.

Abstract: A controlled free radical polymerization process, which includes the steps of: adding a monofunctional iniferter compound to an oxygen-free solvent; heating the solution to a temperature sufficient to allow the iniferter compound to form two carbon centered radical residues; adding a first monomer composition comprising one or more monomers to the solution containing the radical containing residues; polymerizing the first monomer composition to form a quasi-living polymer; and optionally polymerizing a second monomer composition comprising one or more monomers, which are different than the first monomer composition. The resulting non-random copolymer having the general formula: ?-[—Ap—Bs—]t-? where A and B are different compositions of ethylenically unsaturated monomers; p is an integer from 1 to 1,000; s is an integer from 0 to 1,000; t is an integer from 1 to 100; and ? is a residue from the iniferter.

Abstract: This invention relates to processes for transitioning among polymerization catalyst systems, preferably catalyst systems, which are incompatible with each other. Particularly, the invention relates to processes for transitioning among olefin polymerization reactions utilizing Ziegler-Natta catalyst systems, metallocene catalyst systems and chromium-based catalyst systems.

Abstract: Processes for chemically-modifying the surface of an emulsion polymer particle are provided which include providing an aqueous emulsion polymer, a monomer at a level of at least 0.5% by weight based on the weight of the emulsion polymer and a, surface-modifying chemical capable of bonding with the monomer, under conditions where there is no substantial polymerization of the monomer, and then reducing the level of the monomer by at least 50%.

Abstract: The present invention relates to a polymerizable composition comprising a) at least one ethylenically unsaturated monomer and b1) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl and a free radical initiator or b2) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ether. Further aspects of the present invention are a process for polymerizing ethylenically unsaturated monomers, the (co)polymers obtainable by this process and the use of multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyls in combination with a free radical initiator, or a multi-functional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ethers for controlled polymerization. In a particularly preferred embodiment at least one additional heating step at a temperature from 140 to 280° C. is applied after polymerization is completed.

Abstract: It has been discovered that the polymerization of unsaturated compounds, such as butadiene, may be inhibited by the addition of a diene and/or alkanolamine inhibitor. The inhibitor is believed to catalytically destroy peroxides present, such as hydrogen peroxide, which may be present in trace amounts. Particularly useful inhibitors include, but are not limited to, ethylenediamine (EDA) and monoethanolamine (MEA).

Abstract: A high-quality protective film for a dry film resist is provided. A film of a polyethylene is used as the protective film, the polyethylene being prepared by pressurizing ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. and a reaction pressure of not lower than 167 MPa in the presence of a radical polymerization initiator, or by pressuring ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. in the presence of a radical polymerization initiator while allowing a radical polymerization inhibitor to be present in the reaction system.

Abstract: The invention relates to a process for producing water-soluble or water-swellable polymer products with low levels of residual monomers using acrylic acid and/or acrylic acid derivatives, which process is characterized by adding a nitrogen compound to the monomer solution to be polymerized and subsequent heating of the polymer product at temperatures of from 120 to 240° C. The polymers produced accordingly are suitable for use as flocculants, dispersants and absorbents.

Abstract: Disclosed herein is a method for inhibiting the premature polymerization of ethylenically unsaturated monomers comprising adding to said monomers an effective amount of a mixture comprising: A) at least one stable hindered nitroxyl compound having the structural formula: wherein R1 and R4 are independently selected from the group consisting of hydrogen, alkyl, and heteroatom-substituted alkyl and R2 and R3 are independently selected from the group consisting of alkyl and heteroatom-substituted alkyl; and X1 and X2 (1) are independently selected from the group consisting of halogen, cyano, COOR7, —S—COR7, —OCOR7, (wherein R7 is alkyl or aryl), amido, —S—C6H5, carbonyl, alkenyl, or alkyl of 1 to 15 carbon atoms, or (2) taken together, form a ring structure with the nitrogen; and B) at least one inhibitor selected from the group consisting of ortho-quinone, ortho-hydroquinone, para-quinone, para-hydroquinone, and derivatives of the foregoing.

Abstract: A high-quality protective film for a dry film resist is provided. A film of a polyethylene is used as the protective film, the polyethylene being prepared by pressurizing ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. and a reaction pressure of not lower than 167 MPa in the presence of a radical polymerization initiator, or by pressuring ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. in the presence of a radical polymerization initiator while allowing a radical polymerization inhibitor to be present in the reaction system.

Abstract: Methods and compositions for inhibiting the polymerization of vinyl monomers are disclosed. Combinations of aminophenol compounds and nitroxyl radical compounds are effective at inhibiting vinyl monomer polymerization under both processing and storage conditions.

Abstract: Provided is a continuous vapor-phase polymerization method for producing polyolefins. In the method, polymer agglomerates and aggregates are prevented from being formed, and polymer deposition on the wall of reactors and around stirring blades is prevented. The method enables continuous and stable production of high-quality polyolefins, with no pipe line clogging. The method is characterized by a specific supply mode of feeding a catalyst activity retardant such as alcohol into polymerization reactors. Specifically, the retardant is fed into the vapor phase in a polymerization reactor and into the powder phase therein through its side wall. Preferably, the retardant is fed into the powder phase through a plurality of sites of the side wall of the reactor.

Abstract: The present invention provides a method of forming a functionalized polymer. The method includes the steps of providing a living lithium polymer and terminating the polymer with an oxazoline compound selected from an organic halide oxazoline and a branched or unbranched vinyl oxazoline compound. The present invention also provides a compounded rubber article wherein carbon black is compounded with a terminated rubber that is the reaction product of a living lithium polymer and such oxazoline compounds.

Abstract: The present invention is directed to a process for forming a high-cis polydiene. The process includes catalyzing a diene polymerization, and terminating the polymerization with an amine-water termination mixture, preferably a TMEDA-water termination mixture. The catalyst system is a mixture of (a) organoaluminum compounds; (b) organonickel compounds; and (c) fluorine-containing compounds.

Abstract: The present invention relates to a polymerizable composition comprising a) at least one ethylenically unsaturated monomer and b1) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl and a free radical initiator or b2) at least one multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ether. Further aspects of the present invention are a process for polymerizing ethylenically unsaturated monomers, the (co)polymers obtainable by this process and the use of multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyls in combination with a free radical initiator, or a multifunctional triazinyl based 2,2,6,6 tetramethylpiperidine-1-oxyl-ethers for controlled polymerization. In a particularly preferred embodiment at least one additional heating step at a temperature from 140 to 280° C. is applied after polymerization is completed.

Abstract: In a process for the polymerization or copolymerization of ethylenically unsaturated monomers in the presence of polymerization initiators which decompose to form free radicals in a continuously operated polymerization apparatus comprising a fresh gas feed line, a precompressor, a postcompressor, a reactor, a pressure maintenance valve, a high-pressure circuit having a high-pressure product separator and a high-pressure circulation gas return line, a product valve and a low-pressure circuit having a low-pressure product separator and a low-pressure circulation gas return line, nitrogen monoxide or oxygen is introduced as inhibitor into the high-pressure circuit, into the low-pressure circuit and/or the precompressor.

Abstract: The invention relates to a method for producing water-soluble or water-swellable polymerizates with a low residual monomer content from acrylic acid and/or acrylic acid derivatives. The method is characterized by the addition of a nitrogen compound to the monomer solution to be polymerized, an in that the polymerizate is subsequently heated at temperature of 120 to 240° C. The polymerizates produced according to the inventive method are suitable as flocculants, dispersants and absorbers.

Abstract: An aqueous phase inhibitor for quenching free radical polymerization comprising a free radical quenching agent having a hydrophilic tail is disclosed, as well as a coating and related methods. In one embodiment, the free radical quenching agent can either be an N-hydroxylamine or an N-nitrosonamine, the hydrophilic tail can be a polyhydric alcohol tail and the inhibitor can be a concentrate in a liquid medium such as water, alcohol and mixture thereof.

Abstract: It has been discovered that the polymerization of unsaturated compounds, such as butadiene, may be inhibited by the addition of a diene and/or alkanolamine inhibitor. The inhibitor is believed to catalytically destroy peroxides present, such as hydrogen peroxide, which may be present in trace amounts. Particularly useful inhibitors include, but are not limited to, ethylenediamine (EDA) and monoethanolamine (MEA).

Abstract: An aqueous phase inhibitor for quenching free radical polymerization comprising a free radical quenching agent having a hydrophilic tail is disclosed, as well as a coating and related methods. In one embodiment, the free radical quenching agent can either be an N-hydroxylamine or an N-nitrosonamine, the hydrophilic tail can be a polyhydric alcohol tail and the inhibitor can be a concentrate in a liquid medium such as water, alcohol and mixture thereof.

Abstract: In a process for stabilizing chemical compounds having at least one ethylenically unsaturated bond to undesired free radical polymerization, a nitroxyl radical and a chemical compound containing phosphorus in chemically bonded form are added to the unsaturated compound present as pure substance or as a component of a mixture.

Abstract: Free radical polymerizations immediately terminated by a process comprising the addition of an inhibitor solution which contains phenothiazine and at least 50% (w/w) N-alkylpyrrolidone to a system undergoing free radical polymerization, wherein the inhibitor solution also contains p-methoxyphenol (MEHQ).

Abstract: The present invention is a composition for and a method of shortstopping free radical emulsion polymerizations that inhibits the formation of nitrosamines. The composition comprised nitrosamine inhibitors in combination with conventional alkylhydroxylamine shortstoppers. Such nitrosamine inhibitors are based on primary amines, amine-containing polymers, pyrroles, hydroquinones, certain phenols, ascorbic acid, and other well-known nitrosation inhibitors; they may be used individually or as a blend. The compositions are targeted for applications in the emulsion processes for producing rubber latexes and the preparation of rubber products thereafter.

Abstract: The present invention provides a solvent exchange column for continuously exchanging styrene monomer with the solvent used to produce polybutadiene and a method of use therefor. The solvent exchange column includes an exchange plate support structure coupled to and supporting spaced apart exchange plates, wherein each of the exchange plates has holes located therein to allow a passage of fluid therethrough. The solvent exchange column further includes a vapor ventilation system for allowing the volatized solvent to exit the solvent exchange column.

Abstract: A high-quality protective film for a dry film resist is provided. A film of a polyethylene is used as the protective film, the polyethylene being prepared by pressurizing ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. and a reaction pressure of not lower than 167 MPa in the presence of a radical polymerization initiator, or by pressuring ethylene with use of an ultra-high pressure compressor and then polymerizing the ethylene at a reaction temperature of 190° to 300° C. in the presence of a radical polymerization initiator while allowing a radical polymerization inhibitor to be present in the reaction system.

Abstract: A process for preparing highly functionalized polymers comprising the steps of admixing anionically-polymerizable monomers and at least one anionic-polymerization initiator to form an admixture of living polymers, adding at least one lithium alkoxide stabilizer to the admixture of living polymers to form a stabilized admixture, and adding a functionalizing agent to the stabilized admixture.

Abstract: Disclosed is a process for pressurizing ethylenically unsaturated monomers to 200-5000 bar in the absence of a polymerization initiator, which comprises effecting said pressurizing in the presence of nitroxyl compounds of the formula I where R1 and R2 are singly C1-C4-alkyl or combine with the joining carbon atom to form a 5- or 6-membered saturated hydrocarbon ring, R3 is C1-C4-alkyl, and R4 is hydrogen or C1-C12-alkyl. Also disclosed are a process for preparing copolymers by such pressurization and subsequent polymerization and copolymers obtainable thereby.

Abstract: An aqueous phase inhibitor for quenching free radical polymerization comprising a free radical quenching agent having a hydrophilic tail is disclosed, as well as a coating and related methods. In one embodiment, the free radical quenching agent can either be an N-hydroxylamine or an N-nitrosonamine, the hydrophilic tail can be a polyhydric alcohol tail and the inhibitor can be a concentrate in a liquid medium such as water, alcohol and mixture thereof.

Abstract: In the process according to the invention for the aqueous suspension polymerization of vinyl chloride, alone or as a mixture with another vinyl monomer, the polymerization initiator comprises at least one compound chosen from dialkyl peroxydicarbonates, peroxy-tert-alkanoates and diacyl peroxides and use is made, as agent for halting the polymerization, of a mono- or disubstituted hydroxylamine. The resins thus obtained exhibit improved color and heat stability.

Abstract: The process for producing bead polymers having a mean particle size of 0.5 to 50 &mgr;m and a narrow particle size distribution by polymerisation of monomers dissolved in a solvent that constitutes a precipitation agent for the polymers obtained from these monomers is characterized in that the solvent contains 5 to 3000 ppm of sulfur-free radical interceptors.

Abstract: Process for the synthesis of block polymers, homopolymers and copolymers of narrow polydispersity having formula (1) by contacting selected vinyl monomer(s), vinyl-terminated compound(s) and free radicals in which effective control of production of polymer is achieved by controlling the mole ratio of vinyl monomer(s), vinyl-terminated compound(s) and free radicals relative to one another; and polymers produced thereby

Abstract: A process for producing a vinyl chloride polymer is provided which includes the steps of: (A) suspension polymerizing vinyl chloride or a monomer mixture containing vinyl chloride, in an aqueous medium to obtain a polymer slurry; (B) stripping unreacted monomers remaining in the polymer slurry; and (C) subjecting the polymer slurry having passed through the step (B), to dehydration at a temperature of from 80° C. to 95° C., preferably within 60 minutes after the stripping. According to this process, the polymer cake obtained after the polymer slurry Is dehydrated can be made to have a greatly low water content. Hence the drying time in the drying step can be shortened to bring about an improvement in productivity and also to achieve a reduction of energy consumption in the drying step and consequently a reduction of production cost. Vinyl chloride polymer dried products having good anti-initial discoloration properties can be obtained.

Abstract: Disclosed are a resin composition for inhibiting polymerization of a vinyl compound, which includes a resin and 0.1 to 30% by weight based on the resin, of a polymerization inhibitor for the vinyl compound; a resin molding for inhibiting polymerization of a vinyl compound, and a packing for inhibiting polymerization of a vinyl compound in a distillation tower, the resin molding and packing each including this resin composition. Also disclosed are methods for inhibiting polymerization of a vinyl compound, which include contacting the vinyl compound with the resin composition; these methods include processes of inhibiting polymerization of a vinyl compound in a distillation tower, by contacting the vinyl compound in the distillation tower with packing therein which includes this resin composition.

Abstract: In a continuous gas-phase polymerization process for preparing ethylene and propene homopolymers and copolymers, in which ethylene, propene or a mixture of ethylene or propene and C3-C8-&agr;-monoolefins is polymerized in the polymerization zone of a gas-phase polymerization reactor at from 30 to 125° C. and a pressure of from 1 to 100 bar in the gas phase in a bed of finely divided polymer in the presence of a catalyst, where the reactor gas is circulated to remove the heat of polymerization, polymer deposits in the circulating gas line are prevented by metering a catalyst poison having a boiling point above the maximum temperature within the circulating gas line into this circulating gas line in at most such an amount that it does not significantly impair the productivity of the catalyst in the reactor.

Abstract: When a nitroxyl compound is heated in an oxygen-free atmosphere with a vinyl aromatic monomer at 50-140.degree. C. for up to 60 days, it forms an activated inhibitor mixture which is superior to the nitroxyl compound itself in preventing the premature polymerization of a vinyl aromatic monomer during its processing and purification.

Abstract: There is disclosed a method for synthesizing polyolefins having a silyl group at one terminus, the method comprising reacting a monomer of an a-olefin (C.ltoreq.3.ltoreq.10) and a tetrasubstituted silyl radical in the presence of a metallocene catalyst.

Abstract: There is disclosed a method for synthesizing polyolefins having a silyl group at one terminus, the method comprising reacting a monomer of an .alpha.-olefin (C.ltoreq.3.ltoreq.10) and a tetrasubstituted silyl radical in the presence of a metallocene catalyst.

Abstract: The invention describes a dental composition, delivery system and method for making temporary crowns and bridges in which the composition comprises two free-radical polymerizable pastes, one a catalyst paste and the other a base paste, wherein the catalyst paste comprises at least one polymerizable monomer, at least one polymerization initiator which is a peroxide oxidizing agent, at least one first polymerization inhibitor and a filler, and wherein the base paste comprises at least one polymerizable monomer, at least one polymerization accelerator, at least one second polymerization inhibitor, at least one non-polymerizable plasticizer and a filler. These catalyst and base pastes are stored in a dual cartridge from which they can be dispensed with a dispenser, preferably in a 1:1 volume ratio, and can be mixed in a static mixer to form a moldable polymerizing material, which is then applied to a prepared area of one or more teeth in a patient's mouth to form a crown or a bridge.

Abstract: The invention relates to a chain end functionalised polymer of formula: ##STR1## in which: the polymer chain (P) is a hydrophobic chain obtained by radical polymerisation of at least one monomer,R represents a hydrogen atom or a linear or branched hydrocarbon chain having 1 to 8 carbon atoms optionally substituted with at least one group selected from CO.sub.2, NH.sub.2, OH or a phenyl group, itself being optionally substituted,A and B, identical or different, each represent a single bond, a saturated or unsaturated linear or branched hydrocarbon chain having from 1 to 16 carbon atoms, it being possible for it to contain an amide bond or a peptide chain having 2 to 4 amino acids, particularly natural amino acids,the NH.sub.2 and/or COOH groups being free or salified.The invention also relates to the use of the above products as surfactants and more particularly as wetting agents, dispersing agents of solid particles and for preparing microdispersions of polymers, in particular microgels and microlatexes.

Abstract: Selected derivatives of 1-oxyl-2,2,6,6-tetramethyl-4-aminopiperidine are surprisingly effective as inhibitors to prevent the premature polymerization of acrylic and methacrylic acids, their esters, their amides, vinyl acetate and acrylonitrile in the presence of water.

Abstract: A functionalized polymer comprising a polymer having at least one cyclic amine end group defined according to formula (I) ##STR1## where Z is an anionically-polymerized polymer; R.sub.1 is selected from the group consisting of organic groups containing from 1 to about 12 carbon atoms and a bridging bond; each R.sub.2 is independently selected from the group consisting of hydrogen, organic groups containing from 1 to about 12 carbon atoms, and a bridging bond; each R.sub.3 is independently selected from the group consisting of hydrogen and organic groups containing from 1 to about 12 carbon atoms; a is an integer from 4 to about 16; and b is an integer from 0 to about 12; and optionally including a bridge, formed by the selection of two of said bridging bonds, the bridge having 0 to about 6 carbon atoms between the bridging ring members.

Abstract: The present invention relates to a method of terminating a free-radical initiated emulsion polymerization by utilizing a shortstopping agent that contains a stable nitroxyl free-radical or is capable of forming a stable nitroxyl free radical in situ. Besides more effective stopping of polymerization, the present invention does not contain nitrosamine precursors nor is the shortstop agent easily removed during latex and polymer processing.

Abstract: A process for the free radical initiated polymerization of unsaturated species characterized by the use of compound of Formula (I) as chain transfer agents: ##STR1## wherein: X is selected from hydrogen; CN; optionally substituted aryl; COOH; COOR; C(O)NHR.sup.6 ; C(O)NR.sup.7 R.sup.8 ; and halogen;Q is selected from COOR.sup.1 ; CN; and C(O)NR.sup.7 R.sup.8 ;Y is selected from hydrogen; C.sub.1 to C.sub.6 alkyl; C.sub.1 to C.sub.6 alkyl substituted with one or more substituents selected from hydroxy, amino, C.sub.1 to C.sub.6 alkoxy, C.sub.1 to C.sub.6 alkoxycarbonyl, halogen, CN and optionally substituted aryl; C.sub.1 to C.sub.6 alkenyl; and C.sub.1 to C.sub.6 alkynyl;Z is selected from COOR.sup.2 ; CN; and optionally substituted aryl;R.sup.3 and R.sup.4 are the same or different and are selected from hydrogen C.sub.1 to C.sub.4 alkyl and halogen; or R.sup.3 and R.sup.

Abstract: Free radical polymerizations are immediately terminated by adding a phenothiazine-containing solution whose solvent comprises at least 50% of its weight of an N-alkylpyrrolidone.