Abstract: The present invention relates to a copolymer including 20 to 65 wt % of units derived from an alkyl styrene-based monomer; 10 to 40 wt % of units derived from a (meth)acrylate-based monomer; and 20 to 40 wt % of units derived from vinyl cyan-based monomer, based on the total weight of the copolymer, wherein the residual monomer content is 780 ppm or less, and a method for preparing the same.

Abstract: A process for producing an esterified cellulose ether can be efficiently be produced by reacting a moist cellulose ether having a water content of at least 10 percent, based on the weight of the moist cellulose ether, with an aliphatic monocarboxylic acid anhydride, a dicarboxylic acid anhydride or a combination thereof. Further improvements in efficiency and reduction in process steps are achieved in a process for producing an esterified cellulose ether which comprises the steps of a) reacting cellulose with an alkaline material to produce alkali cellulose, b) reacting the produced alkali cellulose with one or more etherifying agents and washing the produced cellulose ether to obtain a moist cellulose ether having a water content of at least 10 weight percent, and c) reacting the moist cellulose ether with an aliphatic monocarboxylic acid anhydride and/or a dicarboxylic acid anhydride and with a depolymerizing agent.

Abstract: A method for manufacturing polyethylene or an ethylene copolymer, including a step of free radical polymerisation or copolymerisation of the ethylene at an initiation temperature varying from 150° C. to 200° C., at a pressure varying from 500 to 3000 bar, in the presence of a peroxidic polymerisation initiator selected from among the peroxide compounds of formula (I) in which R1 and R8 are, separately, a C2-C6 alkyl group; R2, R3, R6 and R7 are, separately, a C1-C5 alkyl group; and R4 and R5 are, separately, a C1-C6 alkyl group.

Abstract: A polymer for an optical film that includes a repeating unit A including a repeating unit represented by the following Chemical Formula 1; and a repeating unit B including a repeating unit represented by the following Chemical Formula 2, wherein R1 to R8, n1 and n2, are defined herein.

Abstract: Composition which contains polymerizable binder and an initiator according to the following Formula I: R1—X—O—O—[Y—O—O—-]nR2??(Formula I) and having a large through-curing depth and a sufficiently long processing time and which cures without the development of high temperatures.

Abstract: The invention provides compositions of matter, methods of their synthesis, and methods of their use in polymerization reactions. The compositions include polyfunctional initiators used to make star polymers when polymerized with monomers. The polyfunctional initiators are synthesized out of a multifunctional core with at least two functional groups and two or more initiator units bonded to the functional groups. The initiator units have two electron-withdrawing groups bonded to a central carbon atom and an azo group between the central carbon atom and the functional group. The polyfunctional initiators are particularly effective because when they decompose to form the radical core of a star polymer, the electron-withdrawing groups prevent the corresponding radical from forming any linear polymer contamination and only desired star polymers result.

Abstract: Described herein are partially fluorinated elastomers and methods of curing comprising (i) a fluoroelastomer comprising interpolymerized units derived from (a) at least one hydrogen containing monomer and (b) at least one nitrile containing monomer, and (ii) a curing agent, wherein the curing agent consists essentially of a peroxide and a coagent.

Abstract: Golf ball components, such as cores, intermediate layers, and covers, formed with compositions including precursors with acrylate functionality crosslinked with a curing agent.

Abstract: Disclosed are novel non-linear vinyl polymers comprised of a multifunctional peroxide, and a cross-linking agent and/or a chain transfer agent, and methods of making such polymers having: at least 0.03 branches/1000 backbone carbons; linear portions with a molecular weight (Mw) of 350,000 or less; 0.2 to 3.0 branches/molecule; or, a Mz/Mw of from 1.7 to 5.7. Methods of quantifying branching are disclosed using a linear reference having 0.0 to 0.06 branches/1000 backbone carbons along with SEC techniques and measurements of molecular weight, molecular size, and concentration. Also discovered is a vinyl polymer resin comprised of from 0.1 to 50 weight percent of non-linear polymers having at least 0.06 branches/1000 backbone carbons, where branching is measured using a heat polymerized polystyrene having from 0.0 to 0.06 branches/1000 backbone carbons as a linear reference.

Abstract: Liquid rubbers that are ordinarily immiscible in liquid thermoset resins can be made miscible by the addition of at least one non-functional aromatic end-group to the polymer chains of such liquid rubber compositions. Such addition may be initiated by high-temperature peroxides in non-functional aromatic solvents. The liquid rubbers are found to improve the fracture toughness of cured thermoset resins while maintaining dimensional and heat resistance.

Abstract: A process for producing a modified polyethylene resin, which comprises the step of melt kneading at least: (A) 100 parts by weight of a polyethylene resin, (B) from 0.1 to 20 parts by weight of at least one compound selected from the group consisting of: (B1) a compound having in its molecule (i) at least one carbon-carbon double or triple bond and (ii) at least one polar group, and (B2) a compound having in its molecule (iii) an OR group and (iv) at least two specific functional groups, and (C) from 0.01 to 20 parts by weight of an organic peroxide having a decomposition temperature of from 50 to 115° C., at which temperature a half-life thereof is 1 minute.

Abstract: A method for carrying out homogenous polymerization reactions in a reactor, wherein monomers and/or prepolymers are fed (apportioned). In a first step, an initiator is optionally admixed with the monomer and/or prepolymer. In a second step, once viscosity is substantially higher, a solvent is added thereto and/or the monomer itself is partially evaporated, it is condensed externally and/or internally and fed back into the reactor.

Abstract: It has been discovered that improved polystyrene products may be obtained by polymerizing styrene in the presence of at least one multifunctional initiator, at least one chain transfer agent, and at least one cross-linking agent. The presence of the multifunctional initiator tends to cause more branched structures in the polystyrene. A mathematical model that helps optimize the levels of these additives for given molecular weights, melt flow indices (MFIs) and zero shear viscosities (?0) has also been discovered.

Abstract: The invention relates to polymer beads having a high content of diacyl peroxides. A prolongation of the pot life in reaction resins based on high-boiling methacrylate esters is achieved due to this high content of peroxides.

Abstract: It has been discovered that improved polystyrene products may be obtained by polymerizing styrene in the presence of at least one multifunctional initiator, at least one chain transfer agent, and at least one cross-linking agent. The presence of the multifunctional initiator tends to cause more branched structures in the polystyrene. A mathematical model that helps optimize the levels of these additives for given molecular weights, melt flow indices (MFIs) and zero shear viscosities (&eegr;0) has also been discovered.

Abstract: The invention relates to a method to safely produce, handle and transport packaged organic peroxide formulations comprising a reactive phlegmatiser and to the use of such packaged material in polymerisation and polymer modification processes, particularly the high-pressure (co)polymerisation process of ethylene and/or the suspension (co)polymerisation process of styrene.

Abstract: It has been discovered that certain compounds serve as polymerization accelerators when employed together with peroxide initiators for the polymerization of vinylaromatic monomers. Suitable accelerators that increase the rate of decomposition of the peroxide initiator include, but are not necessarily limited to, hydroperoxides and/or metallic salts. Representative examples of suitable hydroperoxide accelerators include t-butyl hydroperoxide (TBH), cumyl hydroperoxide, and p-isopropyl cumyl hydroperoxide, whereas suitable metallic salt accelerators include cobalt naphthenate and cobalt acetoacetonate. Use of these accelerators when vinylaromatic monomers are polymerized in the presence of polybutadienes and peroxide initiators results in an increase in grafting as compared with similar copolymers made without the accelerator.

Abstract: The invention relates to a polymerization process wherein at least one initiator is selected from trioxepan compounds of formula I with R1-3 being independently selected from substituted or unsubstituted hydrocarbyl groups.

Abstract: The invention describes a polymer with high transmission for UV rays, this transmission being preserved even after prolonged exposure to UV light (tanning lamps). The polymer is further characterized by a low residual monomer content (determined as methyl methacrylate).

Abstract: The melt of polyvinyl aromatic polymers comprising from 10 to 45 weight % of star branched polymer prepared using a combination of thermal and tetra functional peroxide initiation has an improved melt strength permitting better foam formation for extrusion foam blown with conventional blowing agents and inert gases including CO2 and an improved tensile strength for oriented polystyrene (OPS) articles, e.g. blown film or extruded sheet.

Abstract: The present invention provides to overcome the deficiencies of the prior art, the present invention provides a method of producing a polymer. The method includes taking a product stream from a monovinyl aromatic polymerization system wherein the product stream comprises a polymerized monomer and a monomer. The product stream is introduced into an up-flow heat exchanger in a presence of an initiator, such as a peroxide, that affects a polymerization of the monomer in the up-flow heat exchanger. The initiator may include a low-temperature initiator and a high-temperature initiator where a ratio of the high-temperature initiator to the low-temperature initiator can range from about 0:600 to about 50:600.

Abstract: The melt of polyvinyl aromatic polymers comprising from 10 to 45 weight % of star branched polymer prepared using a combination of thermal and tetra functional peroxide initiation has an improved melt strength permitting better foam formation for extrusion foam blown with conventional blowing agents and inert gases including CO2 and an improved tensile strength for oriented polystyrene (OPS) articles, e.g. blown film or extruded sheet.

Abstract: The new compound t-butylperoxycyclododecyl oxalate is described, as well as a method of preparing it and use of the compound as a polymerization initiator.

Abstract: The present invention provides a macroporous hyperhydroxy polymer formed from a monomer mixture of substantially similar fractions of functional acrylic monomers which are combined to form a compound having a polymer skeleton which provides a high number of hydroxyl sites. The result is a material which, when hydrated, has a pore size relative to oxygen and water which provides a high ratio of free water to bound water. When formed into contact lenses, the material exhibits oxygen permeability approaching that of a static layer of tears of equal thickness and water contents of 95% or greater. The polymer is also suitable for use as burn dressings, bandages, soil hydratants, surface treatments, lubricants and coatings, absorbents, transport membranes and the like.

Abstract: A free radical polymerization process for the preparation of a thermoplastic resin or resins includes the in situ formation of a stable free radical agent from a precursor material in a reactor vessel, introducing a free radical initiator and at least one polymerizable monomer compound into the reactor vessel, and heating a mixture of the free radical initiator, the stable free radical agent, and the polymerizable monomer compound(s) in the reactor vessel to form a thermoplastic resin.

Abstract: A (meth)acrylic premix comprising a (meth)acrylic resin composition (A) containing a (meth)acrylic monomer (a) and a (meth)acrylic polymer (b), an inorganic filler (B), and a curing agent (C), wherein, the component (a) is a (meth)acrylate having a bicyclo ring, fluorine atom, cyclic ether, cyclohexane ring or tricyclo ring, and the component (C) is a radical polymerization initiator having a 10 hours half-life temperature of 75° C. or more; an acrylic SMC or BMC comprising this (meth)acrylic premix and a thickening agent; and a method for producing (meth)acrylic artificial marble, wherein this (meth)acrylic SMC or BMC is cured with being pressurized and heated at a temperature in the range from 105 to 150° C., are provided. These are useful for producing (meth)acrylic artificial marble having various excellent physical properties such as appearance, dimension stability, hot water resistance, weatherability.