Abstract: These compounds contain an oxetane functionality and a cinnamyl functionality. The oxetane functionality is homopolymerizable in reactions that can undergo cationic or anionic ring opening, and the cinnamyl functionality is polymerizable with compounds such as electron acceptor compounds. The dual functionality allows for dual cure processing. The generic structure of such compounds is in which R is a methyl or ethyl group, X and Y independently are a direct bond, or an ether, ester, or carbamate group, and Q is a divalent hydrocarbon (which may contain heteroatoms of N, O, or S), provided that X and Y will not both be direct bonds in the same molecule.

Abstract: A process for producing a crosslinkable silyl group-containing polymer which is excellent in oil resistance, heat resistance, weatherability, low staining properties, and compression set characteristics, includes the steps of radically polymerizing a vinyl monomer in the presence of a thiocarbonylthio group-containing compound with a specific structure, and introducing crosslinkable silyl groups. Also provided is a curable composition which contains the polymer and which is easy to handle.

Abstract: A living polymerization process for preparation of poly(vinyl chloride) (PVC) with controlled molecular weight and molecular weight distribution is described. The polymerization reaction can be initiated by various polyhalocarbon initiators in conjunction with non-metallic reducing single electron transfer reagents as catalysts and accelerated by electron shuttles. The process occurs at room temperature in water or water-organic solvent medium. The polymerization provides PVC with a controlled molecular weight and narrow molecular weight distribution. The halogen containing polymer compositions are useful as, among others, viscosity modifiers, impact modifiers and compatibilizers.

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: Provided is a polymer scale deposition-preventive agent. It includes (A) a condensation reaction product of an aldehyde compound and a hydroxynaphthalene compound and (B) a soluble methoxyl group-substituted cellulose ether. The agent is formed into a film having an adequate polymer scale deposition-preventive property in a single-step application. The time for the application process is shortened to improve productivity. Polymer scales can be prevented from adhering to the inner wall surfaces of the polymerization vessel even if a plenty number of batches for polymerization are repeated.

Abstract: A process for polymerizing unsaturated monomers is disclosed. The process comprises polymerizing, in the presence of a late transition metal catalyst (LTMC), a variety of unsaturated monomers which are traditionally, some of which are exclusively, made by free radical polymerizations. The LTMC polymerization provides the polymer with improved properties such as no free radical residue and narrow molecular weight distribution.

Abstract: Thermally stabilized initiator compositions comprising: (a) at least one dialkyl peroxydicarbonate, and (b) a stabilizing effective amount of a compound of Structure I: wherein R1 and R2 are as defined in the summary of the invention section, processes for their preparation and use are disclosed.

Abstract: The present invention pertains to a process for controlled free radical polymerization or copolymerization of vinyl chloride at a temperature between 40° C. and 95° C., at a pressure between 5 and 30 bar in the presence of a stable free nitroxyl radical.

Abstract: A process for the preparation of polyvinyl chloride (PVC) with controlled molecular weight and molecular weight distribution is disclosed. The polymerization reaction can be initiated by various organic halide initiators in conjunction with a metal catalyst and an optional ligand in organic solvents or water and in the presence of an optional comonomer. The polymerization process provides PVC with a controlled molecular weight and narrow molecular weight distribution. The chlorine containing polymers compositions are useful as, among others, viscosity modifiers, impact modifiers and compatibilizers.

Abstract: A process for producing organic peroxide initiators useful in the polymerization of ethylenically unsaturated monomers. The process for making the organic peroxides includes forming an aqueous emulsion of the organic peroxide. The organic peroxide is dispersed as small droplets of from 1 to 10 microns in size in the aqueous emulsion. The organic peroxide may be added to a polymerization reactor containing an ethylenically unsaturated monomer. The organic peroxide functions as a free radical initiator to polymerize the monomer. The organic peroxide may be substantially free of organic solvents and plasticizers. The resulting polymers are of high quality.

Abstract: A method of producing a vinyl chloride-based polymer by suspension polymerization is provided, by which heat removal performed by a reflux condenser can be increased, but total heat removal performed by the jacket can be reduced, without affecting the quality of the product polymer. The method includes commencing heat removal when or after a polymerization conversion rate reaches 15%, and controlling said reflux condenser so as to remove a fixed quantity of heat per unit of time depending on the polymerization conversion rate as the polymerization process proceeds.

Abstract: A process for producing a crosslinkable silyl group-containing polymer which is excellent in oil resistance, heat resistance, weatherability, low staining properties, and compression set characteristics, includes the steps of radically polymerizing a vinyl monomer in the presence of a thiocarbonylthio group-containing compound with a specific structure, and introducing crosslinkable silyl groups. Also provided is a curable composition which contains the polymer and which is easy to handle.

Abstract: A dispersion stabilizer for suspension polymerization of a vinyl compound contains a modified saponified vinyl ester copolymer (A) having an ethylene content of 1 to 20 mol %, a degree of saponification of 90 mol % or more and a degree of polymerization of 100 to 3,000, a saponified vinyl ester polymer (B) having a degree of saponification of 60 to 90 mol % and a degree of polymerization of 600 to 4,000, and a saponified vinyl ester polymer (C) having a degree of saponification of 30 to 60 mol % and a degree of polymerization of 100 to 600, and in which a component (A)/{component (B)+component (C)} weight ratio if 5/95 to 40/60. The dispersion stabilizer for suspension polymerization of the vinyl compound exhibits quite excellent suspension polymerization stability. Further, the suspension polymerization of a vinyl compound using this dispersion stabilizer can produce a resin having a high bulk density minimizes the formation of milky turbid waste water.

Abstract: The present invention concerns the use of polymer particles in cleaning agents, and such cleaning agents. The polymer particles used according to the present invention are spherical and monodisperse with a particle size which may be varied within the range 10 to 50 micrometers. When all the particles are identical in size and otherwise have identical properties, all the particles will contribute equally to the abrasive effect, and the problems of phase separation phenomena in the final formulation will be reduced. Particles of this type cause no problems with scratching either. Another new and surprising feature of the present invention is that spherical monodisperse polymer particles which have a surface evenly covered with “spikes” of the same polymer material as that of the spherical particle demonstrated much improved washing results in comparison with particles which only had a normal smooth surface. The invented cleaning agents produce good washing results without scratching.

Abstract: A process is provided for producing a vinyl chloride-based polymer by polymerization of vinyl chloride or a monomer mixture containing it in a reaction vessel. Heat generated during polymerization is removed using a reflux condenser. When the polymerization rate is within a range from 30% to 50%, a copolymeric polyether, with a weight average molecular weight of 1,500,000 to 2,000,000, and an ethylene oxide to propylene oxide molar ratio within a range from 78/22 to 82/18, is added to the reaction mass. Foaming of the polymer slurry due to the use of the reflux condenser beyond the point where the polymerization rate reaches 60% is suppressed, and the polymer can be produced with no deleterious effects on the quality of the product polymer.

Abstract: A process for polymerizing vinyl chloride or a monomer mixture containing vinyl chloride in an aqueous medium in a polymerization vessel fitted with a reflux condenser, characterized by starting to add (A) an anti-foam agent, and (B) a partially saponified polyvinyl alcohol with an average degree of polymerization of 100 to 500 and a saponification degree of 75 to 85 mole %, to a reaction mixture during the operation of said reflux condenser, and continuing the addition of (A) and (B) until recovery of unreacted monomers from said polymerization vessel is completed, thereby preventing the polymer slurry from foaming, rising, or scattering during polymerization or recovery of unreacted monomers.

Abstract: Rational combinatorial computational methods use accurate quantum mechanical and molecular modeling techniques to identify optimum polymerization catalysts for polar olefins. Using mechanistic information to model the polymerization reaction, the methods systematically vary components of a catalyst template to calculate a potential energy surface for a number of catalyst candidates. The potential energy surfaces are compared to identify a catalyst for the catalytic polymerization reaction. Internal Lewis acid single site polar olefin polymerization catalyst compositions and compounds for polymerizing polar olefins are also described.

Abstract: A process for producing peroxydicarbonates comprising first reacting at least one inorganic peroxide with at least one alkali metal hydroxide to form at least one alkali metal peroxide. The at least one alkali metal peroxide is added to a mixture of at least one haloformate, at least one dispersant and water. The mixture is homogenized during the entire reaction to form a peroxydicarbonate. The peroxydicarbonate is dispersed as small droplets of from 1 to 10 microns in size in the aqueous mixture. The entire mixture is added to a polymerization reactor containing an ethylenically unsaturated monomer. The peroxydicarbonate functions as the free radical initiator to polymerize the monomer. The peroxydicarbonate is substantially free of organic solvents and plasticizers. The resulting polymers are of high quality.

Abstract: The invention concerns a method of polymerization in aqueous suspension of vinyl chloride alone or mixed with another vinyl monomer, wherein the initiator comprises at least a compound selected from dialkyl peroxydicarbonates, peroxy-tert-alkanoates and diacyl peroxides, and it consists in using, as short-stopper of the polymerization, a stable free nitroxyl radical. The resulting resins have good whiteness.

Abstract: Fluorine-modified comb polymers based on acryloyldimethyltaurine The invention provides water-soluble or water-swellable copolymers obtainable by free-radical copolymerization of

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: Process for the aqueous suspension polymerization of vinyl chloride with the use of dialkyl peroxydicarbonates in solution and process for the manufacture of a solution of dialkyl peroxydicarbonate. The dialkyl peroxydicarbonates with short alkyl chains, preferably diethyl and diisopropyl peroxydicarbonates, are used for the aqueous suspension polymerization of vinyl chloride, in the form of a solution in a dialkyl alkanedicarboxylate which is liquid and insoluble in water. The preferred solvents are hexanedicarboxylates (adipates) derived from adipic acid and from C6-C10alkanols. The peroxydicarbonate concentration of the said solutions is generally 15-40% by weight. The process according to the invention produces vinyl chloride polymers of improved quality resulting in shaped articles exhibiting markedly fewer fisheyes.

Abstract: There is provided a process for producing a vinyl chloride-based polymer by conducting a suspension polymerization in an aqueous medium using an oil soluble polymerization initiator, wherein the oil soluble polymerization initiator utilizes a combination of (A) t-amyl peroxyneodecanoate and (B) a peroxide-based polymerization initiator with a 10 hour half-life temperature in a solution with a concentration of 0.1 mol/liter in trichloroethylene within a range of at least 30° C. but less than 55° C., and when a predetermined polymerization conversion rate is reached, the polymerization reaction temperature is raised by a predetermined amount, followed by addition of an antioxidant to said polymerization mixture to halt the polymerization reaction. According to this process, a vinyl chloride-based polymer with good anti-initial discoloration can be produced in high yield and with good productivity.

Abstract: A polymeric material containing a halogen-containing polymer such as PVC, an inorganic hydroxide and, an acrylic material is described. The presence of the inorganic hydroxide provides a material of superior weathering resistance as compared to materials comprising halogen-containing polymers which do not contain hydroxide.

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.

Abstract: Disclosed are internally blocked borates useful for polymerizable compositions, and polymerizable adhesives made therewith. The internally blocked borates have general structures: wherein X represents —CHR6—, oxygen or sulfur; n is an integer; R1, R2, R3, R4, R5, and R6 are independently selected, for example, from unsubstituted and substituted C1-C10 alkyl, alkylene groups, or aryl groups, including other embodiments further defined, and M is a counter ion with positive charge m.

Abstract: A production process for a vinyl-based polymer is provided. The production process comprises a step for polymerizing a vinyl-based monomer by a radical reaction within an aqueous medium in a polymerization vessel, and a step for supplying a reaction inhibitor with a melting point of no more than 40° C. from a reaction inhibitor supply tank to the polymerization vessel via a reaction inhibitor supply pipe. The reaction inhibitor supply tank and the reaction inhibitor supply pipe are heated, and the reaction inhibitor is added to the polymerization vessel in a liquid state with a viscosity of no more than 200 mPa·s. The reaction inhibitor can be added to the polymerization mixture without the use of an organic solvent even at low temperatures, and problems such as the solidification of the reaction inhibitor inside the supply tank or piping, and subsequent blocking of the piping do not occur.

Abstract: The invention pertains to a process wherein initiators and protective colloids are both metered to a polymerization mixture. This manner of metering allows for improved control of the polymerization rate and an improved reactor space-time yield, and the process will render a polymer with a relatively high porosity.

Abstract: Disclosed are internally blocked borates useful for polymerizable compositions, and polymerizable adhesives made therewith.

Abstract: A dispersion stabilizer for suspension polymerization of a vinyl compound containing a vinyl alcohol polymer (A) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 60 mol % or more and a degree of polymerization of 600 or more and a vinyl alcohol polymer (B) selected from the group consisting of a vinyl alcohol polymer (B1) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 20 to 80 mol % and a degree of polymerization of 100 to 600, a vinyl alcohol polymer (B2) having a degree of saponification of 20 to 60 mol % and a degree of polymerization of 100 to 600 and a vinyl alcohol polymer (B3) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 90 mol % or more and a degree of polymerization of 1,000 or more.

Abstract: The dialkyl peroxydicarbonates with short alkyl chains, preferably diethyl and diisopropyl peroxydicarbonates, are used for the aqueous suspension polymerization of vinyl chloride, in the form of a solution in a dialkyl alkanedicarboxylate which is liquid and insoluble in water. The preferred solvents are hexanedicarboxylates (adipates) derived from adipic acid and from C6-C10 alkanols. The peroxydicarbonate concentration of the said solutions is generally 15-40% by weight. The process according to the invention produces vinyl chloride polymers of improved quality resulting in shaped articles exhibiting markedly fewer fisheyes.

Abstract: A method of producing a vinyl chloride-based polymer by suspension polymerization is provided, by which heat removal performed by a reflux condenser can be increased, but total heat removal performed by the jacket can be reduced, without affecting the quality of the product polymer. The method includes commencing heat removal when or after a polymerization conversion rate reaches 15%, and controlling said reflux condenser so as to remove a fixed quantity of heat per unit of time depending on the polymerization conversion rate as the polymerization process proceeds.

Abstract: A production process for a vinyl-based polymer is provided. The production process comprises a step for polymerizing a vinyl-based monomer by a radical reaction within an aqueous medium in a polymerization vessel, and a step for supplying a reaction inhibitor with a melting point of no more than 40° C. from a reaction inhibitor supply tank to the polymerization vessel via a reaction inhibitor supply pipe. The reaction inhibitor supply tank and the reaction inhibitor supply pipe are heated, and the reaction inhibitor is added to the polymerization vessel in a liquid state with a viscosity of no more than 200 mPa·s. The reaction inhibitor can be added to the polymerization mixture without the use of an organic solvent even at low temperatures, and problems such as the solidification of the reaction inhibitor inside the supply tank or piping, and subsequent blocking of the piping do not occur.

Abstract: A process for producing a vinyl chloride polymer, the process including the steps of charging into a polymerization vessel, vinyl chloride or a monomer mixture containing vinyl chloride, water, and other materials necessary for polymerization, and polymerizing in an aqueous medium the vinyl chloride or the monomer mixture. An antioxidant is added to a mixture of materials before polymerization, or to a polymerization reaction mixture during polymerization or after polymerization. The antioxidant is added in the state of an aqueous dispersion and by means of a uniaxial eccentric screw pump. The aqueous antioxidant dispersion can be added at a constant rate and stably, without causing any block-up of the interior of the pump even when the polymerization vessel is held at a high internal pressure. Hence, vinyl chloride polymers having less uneven plasticizer absorption and having good anti-initial discoloration properties and thermal stability can be produced stably.

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: A dispersion stabilizer for suspension polymerization of a vinyl compound contains a modified vinyl alcohol polymer (A) having an ethylene content of 1 to 20 mol %, a degree of saponification of 90 mol % or more and a degree of polymerization of 100 to 3,000, a vinyl alcohol polymer (B) having a degree of saponification of 60 to 90 mol % and a degree of polymerization of 600 to 4,000, and a vinyl alcohol polymer (C) having a degree of saponification of 30 to 60 mol % and a degree of polymerization of 100 to 600, and in which a component (A)/{component (B)+component (C)} weight ratio is 5/95 to 40/60. The dispersion stabilizer for suspension polymerization of the vinyl compound exhibits quite excellent suspension polymerization stability. Further, the suspension polymerization of a vinyl compound using this dispersion stabilizer can produce a resin having a high bulk density minimizes the formation of milky turbid waste water.

Abstract: A living polymerization process for preparation of poly(vinyl chloride) (PVC) with controlled molecular weight and molecular weight distribution is described. The polymerization reaction can be initiated by various polyhalocarbon initiators in conjunction with non-metallic reducing single electron transfer reagents as catalysts and accelerated by electron shuttles. The process occurs at room temperature in water or water-organic solvent medium. The polymerization provides PVC with a controlled molecular weight and narrow molecular weight distribution. The halogen containing polymer compositions are useful as, among others, viscosity modifiers, impact modifiers and compatibilizers.

Abstract: A composition of matter formed by melt-blending certain thermoplastic polymers and from about 1.0 to about 7.5 wt. % of a fluorocarbon additive, the additive having a lower by surface energy than that of the polymer; the blending resulting in a cooled admixture having a concentration of fluorocarbon additive through a cross-section of the solid composition lower in the interior thereof and higher at the surfaces thereof.

Abstract: A polymerization process comprises (1) contacting at least one polymerizable monomer in the presence of a metal catalyst in a reactor; (2) effectuating polymerization of the monomer; (3) adding a substituted olefin having at least one polar group to the reactor. The substituted olefin is different from the monomer. Vinyl-terminated macromers preferably are generated which can be homopolymerized or copolymerized with the monomer by the metal catalyst. A polymer of an olefin monomer and a substituted olefin comprising a backbone and a plurality of side chains. The polymer is characterized by an Rv of greater than about 0.85, where Rv is a measure of the relative number of vinyl groups in the polymer. In some polymers, the vinyl endgroups are transformed to other useful end groups.

Abstract: A reshapable hair styling composition comprising heterogeneous (meth)acrylic copolymer particles, said particles being the same or different and comprising at least one (meth)acrylic copolymer comprising: (a) units derived from at least one monomer chosen from (meth)acrylate esters of branched and straight chain alkyl alcohols, (b) units derived from at least one monomer chosen from (meth)acrylate esters of saturated and unsaturated cyclic alcohols containing 6 to 20 carbon atoms, (c) optionally units derived from at least one monomer chosen from hydrophilic monomers, and (d) optionally units derived from at least one monomer other than (a), (b), and (c) monomers, wherein said composition provides a reshapable effect.

Abstract: There is provided a polyvinyl chloride dispersion resin from which a product having excellent clarity and heat resistance can be obtained, and which has improved pulverization efficiency and increased recovery percentage in the production process, a plastisol composition and a plastigel composition using the same. The polyvinyl chloride dispersion resin of the present invention is obtained by polymerization using 0.1 to 5.0 parts by weight of an ammonium salt emulsifier based on 100 parts by weight of a vinyl chloride monomer, wherein the polyvinyl chloride dispersion resin has a specific surface area of 5 to 10 m2/g and comprises (A) 10 to 60% by weight of a particle having a particle diameter distribution of less than 0.5 &mgr;m and having at least one peak diameter of the distribution in the range of at least 0.1 &mgr;m to less than 0.5 &mgr;m and (B) 40 to 90% by weight of a particle having a particle diameter distribution of at least 0.

Abstract: Disclosed is a solution that comprises (A) a solvent; (B) about 0.001 to about 20 wt % of a terpolymer that comprises the condensation reaction product of (1) an aromatic compound that contains a benzene or naphthalene ring substituted with the group OR or SR, where R is hydrogen, alkyl from C1 to C15, or aryl, alkaryl, or aralkyl from C6 to C15; (2) about 0.1 to about 10 moles of a carbonyl compound per mole of said aromatic compound; and (3) about 0.1 to about 10 moles of a thiourea per mole of said aromatic compound (C) about 1 to about 5 wt % of a base; (D) about 0.1 wt % to saturation of a salt; and (E) 0 to about 20 wt % of an alcohol. Also disclosed is a method of making the terpolymer in the absence of an acid catalyst and a method of inhibiting the formation of scale on reactor components in contact with polymerizing vinyl chloride monomer.

Abstract: A composition comprising (A) polyvinyl alcohol having an amino group connected to a phenyl group and (B) at least one water resistance-imparting agent selected from polyepoxy compound, aldehyde compound, polyisocyanate compound, and water-soluble oxidizing agent; the composition exhibits outstanding water resistance even when used at room temperature; the composition finds use as a woodworking adhesive, plywood adhesive, and two-part instantaneously curing adhesive which does not require heating for curing.

Abstract: A composition containing a non-flammable chlorofluoro-olefin copolymer having a crystallinity index less than about 10% and a weight-average molecular weight greater than about 1,000,000 daltons, wherein the copolymer has at least two comonomer units of the formula:

Abstract: Water-soluble polymers having a water-soluble backbone and side units having in water a lower critical solution temperature, LCST, the polymers being obtainable by free-radical precipitation polymerization of water-soluble monomers and of macromonomers comprising a unit with an LCST whose heat-induced demixing temperature in aqueous solution is from 5 to 40° C. for a concentration by mass in water of 1% of the said unit. Also described is a process for preparing these polymers by free-radical precipitation polymerization, and aqueous compositions containing these polymers and the use of these polymers and compositions, especially in cosmetics, for the cleansing and/or making up and/or care and/or antisun protection of keratin materials.

Abstract: A new class of “living” free radical initiators that are based on alkylperoxydiarylborane and its derivatives and that may be represented by the general formula.

Abstract: A method of producing a vinyl-based polymer is provided in which the blocking of piping resulting from solidification of a reaction inhibitor does not occur even if the operation of supplying the reaction inhibitor is conducted at a low temperature. This method involves the polymerization of a vinyl monomer via a radical reaction, wherein a reaction inhibitor formed from a compound represented by a general formula (1), shown below, is added to the polymerization system in the form of an aqueous dispersion, either prior to commencement of the polymerization, during the polymerization, or following completion of the polymerization, depending on the effect desired.

Abstract: Thermally stabilized initiator compositions comprising:

Abstract: A process for the preparation of polyvinyl chloride (PVC) with controlled molecular weight and molecular weight distribution is disclosed. The polymerization reaction can be initiated by various organic halide initiators in conjunction with a metal catalyst and an optional ligand in organic solvents or water and in the presence of an optional comonomer. The polymerization process provides PVC with a controlled molecular weight and narrow molecular weight distribution. The chlorine containing polymers compositions are useful as, among others, viscosity modifiers, impact modifiers and compatibilizers.

Abstract: A process for producing a vinyl chloride polymer is provided. This process includes polymerizing vinyl chloride or a monomer mixture containing vinyl chloride in an aqueous medium in a polymerization vessel fitted with a reflux condenser. This process is characterized by starting to add (A) an anti-foam agent, and (B) a partially saponified polyvinyl alcohol with an average degree of polymerization of 100 to 500 and a saponification degree of 75 to 85 mole %, to a reaction mixture during the operation of said reflux condenser, and continuing the addition of (A) and (B) until recovery of unreacted monomers from said polymerization vessel is completed. According to the process, it is possible to prevent the polymer slurry from foaming, rising, or scattering during polymerization or recovery of unreacted monomers.