Abstract: An improved wet strength binder is prepared by a process in which interaction between an olefinic carboxylic acid monomer, such as itaconic acid, and a cross-linker, such as MAGME, is minimized.

Abstract: Substantially homogeneous (meth)acrylic acid/itaconic acid copolymers of number average molecular weight of 500 to 7000 are prepared by copolymerizing in aqueous solution 5 to 90 mole percent acrylic or methacrylic acid monomer with 95 to 10 mole percent itaconic acid monomer at 80.degree. to 120.degree. C. in the presence of a polymerization initiator, the acrylic or methacrylic acid monomer and at least half of the initiator being added separately and continuously to the itaconic acid monomer throughout the polymerization period. The copolymers are employed at a level of from about 0.1 to 100 ppm for prevention of alkaline calcium and magnesium scale formation, such as during seawater evaporative desalination.

Abstract: A conjugated diene copolymer comprising (A) 40 to 90 mole % of a conjugated diene component, (B) 0.5 to 10 mole % of an alpha,beta-ethylenically unsaturated carboxylic acid component, (C) 0.1 to 5 mole % of a polyfunctional alkenyl compound component and (D) 5 to 58 mole % of a monoolefinically unsaturated compound component wherein the intrinsic viscosity [.eta.] of the copolymer as measured at 30.degree. C. in dimethylformamide is 0.01 to 3.0 dl/g, the width (.DELTA.Tg) of the endothermic transition temperature section determined by a differential scanning calorimetry is 45.degree. to 120.degree. C., and the limit temperature (T.sub.1) on the lower temperature side of the endothermic transition temperature section is -40.degree. C. or less.

Abstract: Copolymers of .alpha.-methylstyrene and acrylonitrile having improved composition of uniformity are prepared by emulsion polymerizing a first monomer stream having a weight ratio of .alpha.-methylstyrene/acrylonitrile from about 75/25 to about 85/15 and thereafter polymerizing a second monomer feed stream comprising acrylonitrile.

Abstract: A method of carrying out a continuous aqueous emulsion copolymerization using a single continuously stirred tank reactor to reduce the particle size distribution and the presence of over-sized particles comprises, slowly supplying to a reactor the materials used in the copolymerization, including the monomers which are copolymerized, while maintaining conditions causing copolymerization to proceed until the reactor is filled. The supply is continued while maintaining those conditions until the total supply is in the range of from about 1.5 to about 5 reactor volumes. The excess material in the reactor is removed therefrom and collected in one or more separate vessels, and the product of the copolymerization is then combined and mixed to form a uniform product. The composition copolymerized can be changed during the copolymerization. The emulsion copolymer product is particularly useful in latex paints where it improves the gloss and scrub resistance of the paint.

Abstract: A process for producing monodispersed fine particles of a vinyl polymer is disclosed, which comprises polymerizing monomers containing at least one vinyl monomer selected from the group consisting of aromatic vinyl compounds, acrylic esters, and a methacrylic ester in the presence of (1) a surface active agent represented by formula (I) ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, each represents a substituted or unsubstituted alkyl group having from 4 to 8 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted cyclohexyl group and M represents an alkali metal, (2) from 10.sup.-3 to 10.sup.-1 mol/l of a persulfate as a polymerization initiator, and (3) from 10.sup.-4 to 10.sup.-2 mol/l of a divalent metal sulfate as an electrolyte. Monodispersed vinyl polymer fine particles having a particle size of 1 .mu.m or greater with a very narrow size distribution are obtained.

Abstract: In a process for producing a highly water-absorbent resin comprising subjecting a mixture of (meth)acrylic acid with a water-soluble salt thereof as a monomer to reversed phase suspension polymerization in a hydrophobic solvent in the presence of a dispersing agent, improvements that at least a portion of said monomer is fed sequentially with the progress of polymerization reaction and at least a portion of said dispersing agent is fed sequentially with the progress of polymerization. The resulting resin is useful as a highly water-soluble resin component of sanitary products, or as a humectant/desiccant, a rheology modifier and so on.

Abstract: The present invention provides a process for producing vinyl chloride resin in suspension polymerization of vinyl chloride monomer by the use of a polymerization reactor equipped with a reflux condenser using an improved brumagine-type impeller equipped with auxiliary blade/s, and polymerization is started in a range of 0.8 to 1.0 of the water/monomer ratio, polymerization temperature is raised to 3.degree. to 10.degree. C. at polymer conversion being not more than 50 weight percent, with water being added in the course of polymerization not more than making up for the volumetrical contraction resulting from the progress of polymerization so that upon completion of polymerization the water/monomer ratio is controlled in a range of 1.0 to 1.4. The polyvinyl chloride resin obtained by the present process is superior in quality such as high bulk density and little fish eye with high productivity.

Abstract: An improved emulsion polymerization process for the preparation of high Mooney viscosity terpolymers of ethylene, vinyl acetate, and reactive halogen-containing monomers is provided. In the process, the reactive halogen-containing monomer is added during the polymerization. The ethylene pressure may also be increased during the polymerization.

Abstract: A high solids latex of a functional monomer may be prepared by emulsion polymerization of the monomer charge to a specified overall conversion and then introducing an additional micelle forming surfactant or a unimodal seed latex and continuing the polymerization.

Abstract: This invention provides a method for the manufacture of a high-expansion type absorbent polymer by first causing an absorbent polymer which is obtained by polymerization of a monomer and is possessed of an alkali salt of acrylic acid as a component of polymer to be cross-linked at the time of azeotropic dehydration thereof with a cross-linking agent possessing two or more functional groups in the presence of an inorganic salt and subsequently drying the cross-linked polymer. By the method of this invention, there can be obtained a high-expansion type absorbent material which absorbs water quickly and forms a gel not viscid but permeable to gas. This absorbent material is highly advantageously used as absorbent for sanitary materials free from leaking water and as a water-retaining agent for agricultural applications hardly causing rotton plant roots.

Abstract: A method for producing by suspension polymerization a copolymer comprising a vinyl cyanide compound and an aromatic vinyl compound having excellent transparency, and uniform composition, and a content of the polymerized residue of vinyl cyanide compound in the range of from 50 to 85% by weight comprising the steps of: (a) carrying out initial charging of the total quantity of the vinyl cyanide compound and a partial quantity of the aromatic vinyl compound at a compositional ratio, wherein the content of the vinyl cyanide compound in the resulting copolymer attains an intended ratio within a range of from 50 to 85% by weight; (b) initiating the copolymerization reaction by adding a polymerization initiator having a decomposition half-life at 95.degree. C.

Abstract: A heat-resistant copolymer obtained by copolymerizing (A) 72-82 parts by weight of .alpha.-methylstyrene and (B) 26-18 parts by weight of acrylonitrile, characterized in that the copolymer contains (a) 0-15% by weight of monomer chain --(A)--(A)--(A)--, (b) 50% by weight or more of monomer chain --(A)--(A)--(B)--, and (c) 50% by weight or less of monomer chain--(B)--(A)--(B)--, the total of (a), (b) and (c) being 100% by weight. This copolymer is excellent in heat stability and moldability when molded at high temperatures, and the blending of this copolymer with other thermoplastic resins gives thermoplastic resins with excellent heat resistance.

Abstract: An emulsion polymer of a water insoluble vinylic monomer and an acrylic monomer is formed by precharging a portion of the acrylic monomer and thereafter adding a comonomer charge corresponding to the final desired composition of the vinylic monomer and acrylic monomer at an addition rate generally corresponding to the steady state monomers concentration. A high non-volatiles content is maintained to inhibit the acrylic monomer from partitioning into the aqueous phase.

Abstract: A process for preparing copolymer beads suitable for conversion to ion exchange resins, comprising forming a polymeric matrix containing a plurality of free radicals, and continuously adding to said matrix, under conditions suitable for polymerizing a monomer feed which is imbibed by and polymerized within the matrices. Ion exchange resins prepared from beads made by such process exhibit improved osmotic and mechanical properties.

Abstract: The invention provides a process for the preparation of polymer latex by emulsification of an initiator or initiator mixture and optionally a solvent in the presence of emulsifier in water in a first step and adding a monomer and polymerizing in a second step. The process is carried out by emulsifying an essentially water-insoluble initiator or initiator mixture in the first step at a temperature above the melting point of the initiator or initiator mixture if no solvent is used, and below its decomposition temperature, optionally together with an essentially water-insoluble liquid solvent, which forms a liquid solution together with the initiator or the initiator mixture at the emulsification temperature, then, in a second step adding monomer, possibly additional emulsifier and that part of the desired amount of water which was not added in the first step, and initiating polymerization as per se known by heating.

Abstract: This invention relates to an improved interfacial polycondensation aromatic polycarbonate process which does not require large quantities of strong base to provide a particulate product. The process is specific to interfacial polycondensation processes wherein the polycarbonate is formed in the aqueous phase by using a low organic to aqueous phase volume ratio. The quantity of strong base required to provide a particular product is reduced by adding the aromatic dihydroxy compound to the reaction mixture in small increments. This maintains a high mole ratio of strong base to aromatic dihydroxy compound during reaction.

Abstract: Process for preparing aqueous dispersions of a somewhat water-soluble low-molecular organic material, in which swellable particles prepared in a first step are swelled with the organic material in the second step. When the organic material is a polymerizable monomer the dispersion prepared is converted to a polymer dispersion. In the first step swellable oligomer or oligomer-polymer particles are prepared by(a) dispersing an aqueous mixture containing an oil-soluble initiator or a solution of an oil soluble initiator in an organic solvent, and then swelling the dispersed initiator-containing droplets with monomer and effecting polymerization, or(b) swelling polymer particles in aqueous dispersion with vinyl monomer and an oil-soluble initiator and effecting polymerization, the ratio between initiator and monomer used being so high that in the polymerization an oligomer having a degree of polymerization of 5-200 is formed.

Abstract: An .alpha.-methylstyrene high-content copolymer which is characterized by that it is a copolymer which comprises 65-90 parts by weight of .alpha.-methylstyrene with 35-10 parts by weight of acrylonitrile and 0-5 parts by weight of a copolymerizable vinyl monomer or monomers and that a component having an .alpha.-methylstyrene content of 82% or higher is contained in an amount of 30 parts by weight or more. Such a copolymer may be produced by a process which comprises charging 65 parts by weight or more of .alpha.-methylstyrene and 10% by weight or less based on this .alpha.-methylstyrene of acrylonitrile and a vinyl monomer or monomers all in one portion at the initial stage, making the system fully emulsified, gradually adding 35 parts by weight or less of acrylonitrile and the vinyl monomer or monomers, and carrying out emulsion polymerization until the amount of a polymer produced has amounted to 50 parts by weight or more in such way that the ratio of the .alpha.

Abstract: A modacrylic fiber comprising a copolymer containing acrylonitrile, at least one of vinyl chloride and vinylidene chloride, and a sulfo group-containing vinyl monomer having a relative reactivity of at least 1 to acrylonitrile, in a specific ratio. The copolymer is prepared by polymerizing the monomers, while adding the sulfo group-containing vinyl monomer to the polymerization system under the following condition:16<Y-X<83wherein X and Y are percentages of the amount of a polymer produced at the time of starting the addition and the amount of a polymer produced at the time of finishing the addition, respectively, based on the amount of the whole polymer to be produced. The fiber has an excellent flame resistance and an excellent devitrification preventing property.

Abstract: Disclosed is a polymer and its preparation by reacting part of the monomers in the reactor in such a way as to obtain a high molecular weight product, and reacting at least one other portion of the monomer in the same reactor in such a way as to obtain at least one low molecular weight fraction. The products are useful in contact adhesives, particularly when blended with an aminoplast or phenoplast as a tackifier and crosslinker, and with a thickening agent such as polyvinyl alcohol.

Abstract: The invention pertains to sprayable latex polymers produced by step-wise polymerization of ethylenically unsaturated monomers comprising alkylol acrylamide monomer, functional monomers, and other monomers, wherein the alkylol acrylamide monomers are copolymerized in the second stage monomer addition to preferentially locate alkylol acrylamide groups in the surface portion of the latex polymer particles.

Abstract: Substantially homogeneous (meth)acrylic acid/itaconic acid copolymers of number average molecular weight of 500 to 7000 are prepared by copolymerizing in aqueous solution 5 to 90 mole percent acrylic or methacrylic acid monomer with 95 to 10 mole percent itaconic acid monomer at 80.degree. to 120.degree. C. in the presence of a polymerization initiator, the acrylic or methacrylic acid monomer and at least half of the initiator being added separately and continuously to the itaconic acid monomer throughout the polymerization period. The copolymers are employed at a level of from about 0.1 to 100 ppm for prevention of alkaline calcium and magnesium scale formation, such as during seawater evaporative desalination.

Abstract: Fuel range liquid hydrocarbons are produced by the oligomerization of olefins in a process comprising contacting the olefins containing 5 or less carbon atoms with a water containing medium at a temperature sufficient to cause oligomerization and at a pressure sufficient to maintain the density of the medium at about 0.5 to about 1.0 grams per milliliter.

Abstract: A process for the preparation of emulsion polymers having a solid content of about 65% to about 80% is disclosed. The process comprises the step of adding a monomeric mixture to a reaction system maintained at a temperature of from about 60.degree. C. to about 90.degree. C., the monomer addition not exceeding an hourly rate of about one-fourth of the total monomer to be added, the mixture comprising monomers having a particle size of from about 10-100 microns, the system having therein an emulsifier and initiator at the time of the monomeric addition.

Abstract: A process is disclosed for preparing copolymer latices possessing a solids content of at least about 60 weight percent and a viscosity not exceeding 15,000 cp. Brookfield Viscosity (RVF, Spindle No. 4) at 2 rpm from (a) vinyl acetate in an amount representing from about 10 weight percent to about 95 weight percent of total monomer charge, and (b) at least one monomer selected from the group consisting of acrylate ester, methacrylate ester and vinyl ester of an alpha-branched saturated monocarboxylic acid representing the balance of the total monomer charge.

Abstract: A new method for preparation of hydrophilic fillers has been found, based on high-molecular weight compounds insoluble in water, obtained by the copolymerization of unsaturated monomers, soluble and insoluble in water, either in the form of an aqueous emulsion containing 10-70% by wt. of fillers, or in the dry powdered form having the required particle size, which in the final application are able to sorb reversibly water vapor, and are particularly suited for producing synthetic leather and similar materials.

Abstract: Aqueous polymer dispersions containing up to 75% by weight of polymer are prepared advantageously by emulsion copolymerization in the presence of conventional anionic emulsifiers, polymerization initiators and small amounts of polymerization inhibitors, at conventional polymerization temperatures, by copolymerizing at least two monomers A, which per se are not copolymerizable with one another, mixed with from 60 to 95% by weight of at least one monomer B, which is copolymerizable with both monomers A, in the presence of a polymerization inhibitor, by the emulsion feed process, wherein (a) the initial aqueous phase at the start of the monomer emulsion feed contains from 0.01 to 0.

Abstract: The present invention relates to a process for producing low energy dispersion vinyl copolymers which, in a plastisol, can be fused at lower temperatures or in a shorter period of time than presently available dispersion vinyl copolymers. It has been found that if, instead of adding all the comonomer batchwise prior to the start of the reaction, the comonomer, such as methyl acrylate, for example, is metered into the reactor continuously, or intermittently, during all or part of the polymerization reaction period, a dispersion vinyl copolymer is produced that has a lower plastisol viscosity for a given comonomer content. Plastisols made from the vinyl copolymers of the present invention have good flow properties and the fused films made therefrom have high gloss, high clarity and good mechanical strength, even when fused at low temperatures.

Abstract: Crystallizable, controlled composition interpolymers consisting essentially of (a) from about 88 to about 92 mole percent vinylidene chloride, (b) from about 8 to about 12 mole percent methyl methacrylate, and (c) up to about 3 weight percent, based on the combined weight of (a) and (b), of one or more ethylenically unsaturated comonomers; such interpolymers having a relative viscosity of at least about 1.40.degree. at 25.degree. C. as a 1 percent solution in tetrahydrofuran and being capable of forming substantially haze-free solutions when present in an amount of about 20 percent solids in a solvent mixture consisting of 65 percent by weight tetrahydrofuran and 35 percent by weight toluene.

Abstract: A pastable emulsion polymer comprised of carboxylated monomer/vinyl chloride/vinyl acetate terpolymer having improved strength of adhesion produced by emulsion copolymerization and containing, per polymer weight,from 60% to 98% by weight of vinyl chloride monomer units,from 1% to 29% by weight of vinyl acetate monomer units, andfrom 1% to 15% by weight of carboxyl-containing monomerunits selected from the group consisting of olefinically-unsaturated monocarboxylic acids, monoallyl esters of non-ethylenically unsaturated dicarboxylic acids, and monovinyl esters of non-ethylenically-unsaturated dicarboxylic acids. The terpolymers are manufactured by the copolymerization of vinyl chloride, vinyl acetate, olefinically-unsaturated monocarboxylic acids and/or monoallyl esters and/or monovinyl esters of non-ethylenically unsaturated dicarboxylic acids in an aqueous emulsion. The pastable terpolymers, after empasting are used for coating flexible sheet-like articles.

Abstract: This invention relates to a vinyl acetate-ethylene copolymer containing emulsion particularly adapted for the preparation of nonwoven goods. The vinyl acetate-ethylene emulsion is prepared by an improved process for producing an aqueous emulsion suitably adapted for producing non-woven goods said emulsion containing a vinyl acetate-ethylene copolymer wherein said copolymer contains from about 75-96% by weight of vinyl acetate. It is produced by forming an aqueous suspension of vinyl acetate, ethylene, and stabilizer, initiating the polymerization of the reaction mixture by the addition of catalysts, and adding from about 0.5-10% by weight of the vinyl acetate of a crosslinkable monomer. The improvement for enhancing the absorptivity of the copolymer comprises:pressurizing the reactor with ethylene to an initial ethylene equilibrium pressure of from about 100 to 1,000 psig;initiating the reaction mixture by the addition of catalyst at a temperature from about 10.degree.-35.degree. C.

Abstract: A process for producing a resin having a high heat resistance with a high polymerization conversion by emulsion-polymerizing .alpha.-methylstyrene (AMS), methyl methacrylate (MMA) and acrylonitrile (AN), characterized in that the polymerization is conducted in two steps; A monomer mixture consisting of 60-85% by weight of AMS, 2-30% by weight of MMA and 5-20% by weight of AN is subjected to copolymerization in the first step until 25-85% by weight, based on the weight of the final copolymer, of a copolymer is formed, and in the second step, at least one monomer of the above three monomers is added to the polymerization system to adjust the composition ratio of the three monomers in the polymerization system so as to fall in the region surrounded by the lines connecting points A, B, C, D and E in the triangular coordinate graph indicating the quantitative relationship of the three monomers, and the resulting monomer mixture is subjected to polymerization conditions to complete the polymerization.

Abstract: A process for preparing a thermoplastic resin having high heat resistance by emulsion polymerization of an .alpha.-alkylstyrene compound of the formula: ##STR1## wherein R.sub.1 is C.sub.1 -C.sub.3 alkyl and R.sub.2 is hydrogen, C.sub.1 -C.sub.3 alkyl or halo(C.sub.1 -C.sub.3)alkyl and an unsaturated nitrile in a weight proportion of 65:35 to 80:20 in the presence of a radical initiator, characterized in that the whole amount of the .alpha.-alkylstyrene compound and 10 to 99% by weight of the unsaturated nitrile on the basis of its total amount are first subjected to polymerization and, after the polymerization, the remaining portion of the unsaturated nitrile is added to the reaction mixture and the resultant mixture is subjected to further polymerization until the polymerization is substantially completed.

Abstract: A process for preparing a carboxylated latex containing an N-alkylolamide of an unsaturated carboxylic acid comprises carrying out the polymerization reaction in two or more stages in which the majority (or all) of the N-alkylolamide monomer is supplied to the second stage. The reaction may be carried out using a batch procedure but a continuous reaction is preferred. The product latex is particularly suitable for paper and textile applications and especially for use in paper coating compositions.

Abstract: Styrenic polymer particles having a uniform particle size distribution are prepared without the formation of fine polymer powders. The suspension polymerization process which comprises providing a stirred, aqueous suspension of polymeric seed particles, adding gradually to the suspension styrenic monomer and polymerizing it therein, and continuing the addition of monomer as the polymerization proceeds, may be improved by introducing the styrenic monomer below the surface of the suspension.

Abstract: Vinyl acetate-ethylene copolymer latices having an inherent viscosity of not less than about 1.90 and demonstrating superior performance in the Time of Set Test and Vinyl Wetting Test are prepared by the process which comprises copolymerizing from about 60% to about 95% by weight of vinyl acetate monomer with from about 40% to about 5% by weight of ethylene monomer in an emulsified reaction medium containing:(a) at least one surface active agent in an amount of not less than about 1.0% by weight, and not more than about 2.0% by weight, of the total monomer,(b) a catalyst, and(c) a protective colloid,the total weight of the surface active agent and vinyl acetate monomer being introduced into the reaction medium in delayed increments prior to and after the commencement of copolymerization.

Abstract: The binary suspension polymerization of a water soluble monomer and an organophilic or hydrophobic monomer having a low Tg in an integrated aqueous suspension system wherein the suspension medium for said organophilic monomer droplets comprises a hydrophilic monomer having a higher rate of reaction than the hydrophobic monomer and water in a mixture such that a solution of between about 1,000 and about 100,000 cps Brookfield viscosity is maintained in the reaction zone during polymerization of the organophilic droplets.

Abstract: An improved two-step process for producing bimodal emulsion polymer particles includes the steps of first providing uniform size polymer particles in the first stage by feeding monomers to the reaction mixture at a rate faster than the rate the monomers polymerize, and followed by a controlled second stage monomer polymerization by feeding monomers to the reaction mixture at a rate slower than the rate of polymerization of the monomers. The polymer particles are bimodal and are particularly useful in coatings, adhesives, and plastics.

Abstract: A process is described by which plastics dispersions of high water and saponification resistance are obtained which, due to their small average particle size diameter of 0.01 to 0.06 microns are especially useful as primers for porous substrates. In their penetration characteristics, the present dispersions can be compared with conventional solvent-based primers at comparable solids content. The dispersions are obtained in a one-step polymerization process.

Abstract: The process of continuously polymerizing acrylonitrile and other non-acidic mono-olefinic monomers with small amounts of certain acidic mono-olefinic monomers copolymerizable with acrylonitrile wherein the acrylonitrile and other non-acidic mono-olefinic monomers are continuously charged to a reactor and the acidic monomer is fed to the reactor in increments and in cycles, with a tall amount in a given cycle of 0.5 to 5 weight percent of the acidic monomer, based on total monomer weight fed in the cycle, being fed to the reactor during each cycle. Each cycle is made up of two time periods, with at least 65 percent of the acidic monomer being fed during the first time period and up to 35 percent being fed during the second time period. Preferably, all of the acidic monomer is fed to the reactor in the first time period. The first time period of the cycle is 5 to 25 percent of the second time period and the sum of first and second time periods, or cycle time, is about 15 to 25 percent of the reactor dwell time.

Abstract: The invention relates to a process for reducing the monomer content in expandable thermoplastic beads which are produced by polymerizing an ethylenically unsaturated monomer or a mixture of such monomers in aqueous suspension in the presence of a blowing agent. The residual monomers in both the beads and the process water are reduced by treatment of the slurry of beads and water obtained after polymerization in a vessel at a temperature above 65.degree. C. in the presence of at least one water-soluble initiator. In order to avoid the expansion of the beads during the course of monomer reduction the vessel is kept completely filled with a liquid, preferably water, during the temperature treatment.

Abstract: In the aqueous emulsion free radical polymerization of dienes and copolymerization of dienes and vinyl monomers using mercaptan modifiers there is added at at least 75% conversion a large amount of mercaptan modifier as compared to that previously added and the polymerization is stopped at about 90-99+% conversion to provide processable polymers having a reduced amount of or no gel.

Abstract: In the production of a water-soluble, cationic high polymer of (A) at least one of acrylamide and methacrylamide and (B) at least one of ammonium type monomers of either one of the formulas: ##STR1## wherein R.sub.1 is a hydrogen atom or a methyl group, R.sub.2 and R.sub.3 are each a lower alkyl group, R.sub.4 is a hydrogen atom, a lower alkyl group, an aryl group, a hydroxy(lower)alkyl group, a benzyl group or a group of the formula: --CH.sub.2 COO(CH.sub.2).sub.m CH.sub.3 (m being an integer of 0 or 1), R.sub.5 .crclbar. is a group of either one of the formulas: --(CH.sub.2).sub.2 COO.crclbar. and --(CH.sub.2).sub.3 SO.sub.3 .crclbar.

Abstract: In a process for polymerization of tetrafluoroethylene with a copolymerizable modifier in an aqueous medium containing a polymerization initiator and a dispersant to produce a modified tetrafluoroethylene polymer containing 0.001 to 2 wt.% of the copolymerizable modifier based on the weight of the polymer, a process for producing the modified tetrafluoroethylene polymer characterized in that:(1) chlorotrifluoroethylene is used as said copolymerizable modifier,(2) at least 50 wt.% of the copolymerizable modifier to be incorporated into the polymer is introduced into the polymerization system after 70 wt.% of the polymer to be finally formed has been formed, and(3) after 90 wt.% of the polymer to be finally formed has been formed, the concentration of said copolymerizable modifier is maintained at at least 0.01 mol.% based on the total amount of tetrafluoroethylene and the modifier in the polymerization system.

Abstract: Methyl methacrylate polymer powders especially suitable for making plastisols and organosols are prepared by an improved process comprising stepwise emulsion polymerization in aqueous media in the absence of emulsifiers and surfactants and in such manner that at least most of the monomer added at each step is consumed before the addition of the succeeding portion, followed by isolation of the polymer powder by evaporation of the latex at a temperature that is at least 30.degree. C., preferably 40.degree.-50.degree. C., below the glass transition temperature of the polymer.

Abstract: In the process for producing the aqueous emulsion of vinyl chloride/vinyl acetate/ethylene terpolymer by polymerizing vinyl chloride, vinyl acetate and ethylene in an aqueous dispersion system under ethylene pressure in the presence of an emulsifier and/or protective colloid using a radical initiator, the improvement which comprises adding vinyl chloride and vinyl acetate to said aqueous dispersion system at substantially fixed rates while maintaining a required amount of unreacted vinyl acetate in the system, and, after completion of addition of vinyl chloride, adding additional vinyl acetate of 3 to 20% by weight based on the total amount of vinyl acetate which has been added until that time and continuing the polymerization until the concentration of vinyl acetate in the system is decreased to 1% by weight or less, wherein the volume of the aqueous dispersion system is at least 50% by volume based on the volume of the reactor when addition of the additional vinyl acetate is completed.

Abstract: A poly(vinyl chloride) resin composition comprised of an admixture of poly(vinyl chloride) resin and a clear or translucent polymeric material comprised of a non-uniform copolymer comprised of acrylonitrile, styrene and acrylate ester. The clear polymeric ASA material is a good impact modifier for PVC. The admixture contains from 3 to 15 percent by weight, based on the admixture, of the clear polymeric material. The clear polymeric material has a weight ratio of acrylonitrile and styrene acrylonitrile, styrene and acrylate ester which is between about 40 to 60 and about 60 to 40. The PVC resin combination, in dry form, can be conventionally hot processed or fabricated.

Abstract: This invention relates to a process for production of expandable thermoplastic beads with improved yield and with improved expandability. The process involves maintaining the polymerization vessel full of liquid at a certain pressure or with a gradually increased outside pressure on the reaction media.

Abstract: An alkali metal or ammonium bisulfite or metabisulfite added incrementally to a polymerizing aqueous solution of dimethyldiallylammonium halide enables control of the intrinsic viscosity of the resulting polymer within desired limits without adverse effect on monomer conversion.