Abstract: A process for producing polymer particles with an irregular shape by polymerizing a water-soluble polymerizable monomer in a system comprising a hydrophobic organic solvent inert to the polymerization and an aqueous solution of the water-soluble polymerizable monomer, characterized in that the system further contains an anionic surfactant.

Abstract: There is a need for polymers which are utilized in automotive interiors which offer increased heat and ultraviolet light resistance. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat and ultraviolet light resistance.

Abstract: A polymerization process for the preparation of thermoplastic resin or resins comprising heating a mixture comprised of a free radical initiator, a stable free radical agent, at least one polymerizable monomer compound, and a sulfonic acid salt polymerization rate enhancing compound, to form a thermoplastic resin or resins with a high monomer to polymer conversion and a narrow polydispersity.

Abstract: A process of making polymeric matte bead particles for use in photographic elements which comprises forming a suspension of ethylenically unsaturated monomer droplets in an aqueous media, subsequent to the formation of droplets and before commencement of reaction, adding to the aqueous media an effective amount of a hydrophilic colloid to improve adhesion and polymerizing the monomer to form solid polymeric particles.

Abstract: There is a need for polymers which are utilized in automotive interiors which offer increased heat and ultraviolet light resistance. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat and ultraviolet light resistance. This invention discloses a rubbery polymer which can be blended with polyvinyl chloride to make leathery compositions having good heat and ultraviolet light resistance, said rubbery polymer being comprised of repeat units which are comprised of (a) butyl acrylate, or optionally a mixture of butyl acrylate and 2-ethylhexyl acrylate containing up to about 40% 2-ethylhexyl acrylate, (b) at least one member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate, and ethyl acrylate, (c) acrylonitrile, (d) styrene, (e) a half ester maleate soap, and (f) a crosslinking agent.

Abstract: Polysuccinimide is prepared by reacting an unsaturated C.sub.2 dicarboxylic acid or anhydride thereof, e.g., maleic acid, fumaric acid, and maleic anhydride, with a particulate ammonium salt that is thermally decomposable to liberate ammonia. The reaction is carried out at a temperature which is above the thermal decomposition temperature of the ammonium salt and for a time period which is sufficient for the acid or anhydride to react with the ammonia liberated from the ammonium salt and for polymerization to occur. The present method avoids the prior art problems of controlling ammonia losses and water removal. The product polysuccinimide can be readily hydrolyzed to polyaspartic acid or a salt thereof, if desired.

Abstract: A polymerizable composition comprising:(a) a monomer; and(b) a sulfinate represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.5 each represents a substituent having 2 to 6 carbon atoms, R.sup.2, R.sup.3 and R.sup.4 each represents an atom or substituent inert to the monomer (a), M.sup.n+ represents a n-valent cation, and n represents an integer of 1 to 4.

Abstract: In a method of preparing styrene plastics, the water medium containing tricalcium phosphate is prepared in situ (0.15 to 1.5 wt. %). Then, calcium carbonate (0.07 to 0.35 wt. %) is heated and dispersed therein. Thereafter, the monomer/comonomers/prepolymer, and secondary sodium alkylsulphates (0.001 to 0.020 wt. %) are introduced into the suspension polymerization process at 15 to 47% conversion. This method permits production of styrene plastics using a common technology, while providing specified bead size distribution, low concentration of dust fractions, and enhancement of the process stability.

Abstract: A process for preparing a free-flowing redispersible powder composed of a vinyl-pyrrolidone/vinyl acetate copolymer containing 15-40% by weight of vinylpyrrolidone units wherein the mixture of the monomers is copolymerized in organic solution, the resulting solution is, after addition of a surfactant, subjected to replacement of the solvent by water, and the resulting dispersion is spray- or freeze-dried, and the use of the redispersible powder for producing paints and coating compositions, glues and adhesives and, in particular, the matrix and/or coating of solid slow-release pharma-ceutical forms and of hair-spray formulations are described.

Abstract: A cyanoacrylate monomer adhesive formulation which has improved thermal properties resulting from the inclusion in the formulation of an effective amount for enhancing the thermal resistance of the cured polymer of a naphthosultone compound having at least one strong electron withdrawing group thereon, suitably a nitro group.

Abstract: Provided is a process useful for making acrylic polymers of methacrylic acid having improved shear stability. The process provides polymers useful as enteric coatings for medicaments having improved coating efficiency of pharmaceutical forms. Also provided are medicaments in solid form coated with said polymers.

Abstract: The specification discloses a method for making DCPD based resins that have relatively narrow molecular weight distributions. The method comprises thermally polymerizing dicyclopentadiene monomer in the presence of one or more strong acids, preferably with an olefinic modifier, to provide a dicyclopentadiene oligomer. Optionally, an organic sulfur species can also be used to further effect molecular weight control. For end-use performance in inks, adhesives, coatings and other related areas, the invention provides dicyclopentadiene oligomer resins having weight average molecular weights less than 1000 and relatively narrow molecular weight distributions, as measured by a polydispersity index, of less than about 2.3. Among the strong acids that are effective for controlling molecular weight, hypophosphorous acid is preferred because it gives light colored resins.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aromatic dibasic acid dihydrazide compound, and (B) an aromatic tetracarboxylic acid anhydride. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: The present invention discloses an alkylidenenorbornene polymer comprising as the essential constituent at least one kind of the structural unit represented by the formula ##STR1## wherein R.sub.1 denotes an alkyl group of 1-4 carbon atoms and R.sub.2 denotes a hydrogen atom or an alkyl group of 1-5 carbon atoms, and a process for producing the same.According to the present invention, an alkylidenenorbornene polymer is obtained which is excellent in light resistance, transparency, heat resistance and moisture resistance and is useful as an optical polymeric material.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aromatic compound having at least two amino groups and (B) an aromatic bis-ester anhydride. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A method for producing polysuccinimide is provided. Thermal polymerization of maleamic acid at a temperature of from about 160.degree. C. to about 330.degree. C. produces polysuccinimide. The reaction is optionally conducted in the presence of one or more processing aids, solvents or diluents. The polysuccinimide is particularly useful as a detergent additive.

Abstract: This invention provides a process by which a polymer having a hydroxyl group at both terminals can be easily obtained with a cheap price and good efficiency from a wide field of vinyl-based monomers including polar ones. The process is arranged in such a manner that the polymerization of a vinyl-based monomer (a) is performed in the presence of an alcohol (b) having no addition-polymerization reactivity by using an initiator (c) consisting essentially of a peroxide and, on this occasion, at least one of catalysts (d) selected from a group consisting of an organic sulfonic acid compound having no addition-polymerization reactivity and an inorganic acid is further used and a reactor does not substantially contain any component other than the (a), (b), (c) and (d).

Abstract: Paste-forming polymers of vinyl chloride are produced by discontinuous polymerization in the presence of a conventional predispersion of emulsifier, dispersion acid, water and optional monomer-soluble catalyst. The predispersion is prepared only with 30-80% by weight of the amount of emulsifier required in total. The remainder of the emulsifier, or a component forming the emulsifier, is added in metered amounts as an aqueous solution batchwise or continously to the polymerization mixture after a conversion of 10-60% by weight.The thus-obtained polymers lead to pastes of an especially low viscosity, even under high shear stress, and result in open-cell plasticized foam materials having a good elastic memory capacity.

Abstract: Process for producing ethylene-vinyl ester copolymers using a polymerization solvent of a dialkyl sulfoxide (process X); process for producing ethylene-vinyl alcohol copolymer by liquid phase saponification using a solvent of a dialkyl sulfoxide (process Y); and process for producing shaped articles which comprises contacting the ethylene-vinyl alcohol copolymer obtained by the process Y, or that obtained by saponifying the ethylene-vinyl ester copolymer obtained by process X, to a non-solvent for ethylene-vinyl alcohol copolymer.Ethylene-vinyl ester copolymers having a wide range of ethylene content and higher degree of polymerization than that with solution polymerization using methanol.The rate of saponification is higher than that with single solvent system of lower alcohol.Production cost is low, because production process of polymer is directly connected to that of shaped articles utilizing the polymer.

Abstract: A method for preparing a graft copolymer is here disclosed which is characterized by comprising the step of carrying out a living polymerization of at least one (meth)acrylic ester by the use of a polymeric compound as an initiator having one or more units represented by the following formula (I) in a molecular chain substantially in the absence of water in the presence of a Lewis acid or a donor compound of an anion selected from the group consisting of HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- and F.sup.- : ##STR1## wherein R is hydrogen or an alkyl group having 1 to 6 carbon atoms, and R' is an alkyl group having 1 to 12 carbon atoms.

Abstract: A water-dispersible, inherently tacky pressure-sensitive adhesive comprising a tacky emulsion polymer formed of from about 80% to 90% by weight of monomers comprising a major portion of at least alkyl acrylate containing from 4 to about 8 carbon atoms in the alkyl group and from about 20% to 10% by weight hydroxyethyl methacrylate, said emulsion polymer formed in the presence of anionic and nonionic surfactants to provide a polymer having a glass transition temperature of -15.degree. to -50.degree. C. A sufficient amount of chain transfer agent is employed to provide an emulsion polymer which when coated on a repulpable paper substrate enables recovery of paper fibers substantially free of adhesive under conditions of TAPPI Useful 204, and is resistant to loss of adhesive properties on exposure to high humidity.

Abstract: Disclosed is a free radical polymerization process for the preparation of a thermoplastic resin or resins comprising heating a mixture of a free radical initiator, a stable free radical agent, and at least one polymerizable monomer compound to form a thermoplastic resin or resins with a high monomer to polymer conversion; cooling said mixture; optionally isolating the thermoplastic resin or resins; and optionally washing and drying thermoplastic resin or resins.Related free radical processes are also disclosed for the preparation of mixtures and block copolymer thermoplastic resins. Resins prepared by the disclosed processes possesses a narrow polydispersity and a modality that is controlled by the selection of a free radical initiator and stable free radical agent addition step or steps.

Abstract: The present invention relates to a process for the preparation of N-(hydroxyphenyl)maleamic acid and various dimers and oligomers thereof. The process is characterized by heating, in the absence of any solvent, N-(hydroxyphenyl)maleamic acid at a temperature ranging from about 150.degree. to about 250.degree. C. in the presence of an acid catalyst. This unique process avoids the need to recover expensive highly polar solvents. The present invention also relates to use of these maleimide containing compounds in rubber. The use of the blend of hydroxyphenyl maleimide and the various dimers and low molecular weight oligomers impart superior properties to rubber when compared to the use of hydroxyphenyl maleimide alone in rubber.

Abstract: The premature free-radical polymerization of a non-linear, readily polymerizable organic monomer under conditions where the monomer would otherwise polymerize is inhibited by incorporating within the non-linear, readily polymerizable monomer a polymerization inhibiting amount of a fullerene or a derivative thereof.

Abstract: There is disclosed a process for producing an acrylamide polymer which comprises polymerizing acrylamide monomer alone or a monomer mixture composed of 50 mole % or more of acrylamide monomer and a monomer capable of copolymerizing with acrylamide monomer in the presence of an azo series polymerization initiator and 0.1% by weight or more of 2-mercaptobenzothiazole or a salt thereof based on the weight of the monomer in an aqueous medium having a pH of 6 or higher at a temperature range of 5 to 100.degree. C., and then drying the resulting material.

Abstract: This invention discloses methods of polymerization in the field of PVC dispersion resins, in particular, dispersion PVC, made by the emulsion or microsuspension process with or without monomer metering. The invention achieves improved initial plastisol color without destroying blush resistance by employing techniques which entail at least two air evacuation steps. In the preferred embodiment a specified amount of a metabisulfite reducing agent is incorporated into the polymerization medium and/or monomer mixture followed by polymerization initiaton and further processing. Another disclosure of the invention is a simple method for reducing the haze of dispersion resin plastisol films thereby improving their clarity by the addition of a small amount of non-copolymerizable polybasic carboxylic acid to the dispersion resin or monomer dispersion prior to isolating the resin. The preferred poly basic acids are non-ethylenic unsaturated, di- or tri-carboxylic acids like citric acid and tartaric acid.

Abstract: A cyanoacrylate monomer adhesive formulation which has improved thermal properties resulting from the inclusion in the formulation of an effective amount for enhancing the thermal resistance of the cured polymer of a mono, poly or hetero aromatic compound characterized by at least three substitutions on an aromatic ring thereof, two or more of said substitutions being electron withdrawing groups selected from the group consisting of NO.sub.2, CN, CF.sub.3, NR.sup.1.sub.3.sup.+, SR.sup.1.sub.2.sup.+, C(.dbd.O)R.sup.1, C(.dbd.O)OR.sup.1, NO, CCl.sub.3, SO.sub.2, S(.dbd.O), SO.sub.3, SO.sub.2 R.sup.1, SO.sub.2 OR.sup.1 and F, one or more of said substitutions being leaving groups selected from the group consisting of F, Br, Cl, I, NO.sub.2, CN, SOR.sup.1, SO.sub.2 R.sup.1 and SO.sub.2 OR.sup.1, and R.sup.1 is an optionally substituted hydrocarbon group. Example such compounds have the formula: ##STR1## where L is the leaving group and the W groups are the electron withdrawing groups.

Abstract: In the emulsion polymerization of monomers wherein at least one monomer is substantially water insoluble, the presence in the emulsion polymerization mixture of one or more emulsifiers having the formula:[R.sup.1 O--(CH.sub.n H.sub.2n O).sub.x --][R.sup.2 O--(C.sub.n H.sub.2n O).sub.y --][R.sup.3 O--(C.sub.n H.sub.2n O).sub.z --]P.dbd.O(I)in whichR.sup.1 is a group corresponding to formula IIa or IIbCH.sub.3 --(CH.sub.2).sub.a --CH(OH)--(CH.sub.2).sub.b --CH(SO.sub.3 M)--(CH.sub.2).sub.c --CH.sub.2 -- (IIa)orCH.sub.3 --(CH.sub.2).sub.a --CH(SO.sub.3 M)--(CH.sub.2).sub.b --CH(OH)--(CH.sub.2).sub.c --CH.sub.2 -- (IIb)or a residue formed by elimination of one water molecule from the group corresponding to formula IIa or IIb, R.sup.2 and R.sup.3 may be the same or different and represent hydrogen or a residue having the meaning defined for the group R.sup.

Abstract: Fluoroalkyl sulfinates were synthesized and used as a source of fluoroalkyl radicals in aqueous emulsion polymerization. The resulting polymers contained a high level of perfluoroalkyl end groups. When fluoroalkyl disulfinates were utilized, the fluoroalkyl moiety and was incorporated in the polymer backbone. These disulfinates act as monomers, yielding fluoropolymers with specific micro structural fragments, derived from the parent perfluoro disulfinate. Novel fluoropolymers can thus be prepared.

Abstract: (Co)polymer particulates soluble in their corresponding (co)monomer composition, e.g., particulates of acrylic, methacrylic or styrene polymers, are produced by finely dispersing an aqueous phase including at least one polymerization initiator in an organic phase which comprises such (co)monomer composition and at least one nonsolvent for such (co)polymer which is miscible with such (co)monomer composition, and suspended emulsion polymerizing such mixed-phase polymerization recipe.

Abstract: A molded article comprising a cross-linked ring-opened polymer produced by the metathesis polymerization of a dicyclopentadiene (DCPD) monomer, which may be dicyclopentadiene (DCPD) or of a mixture of (DCPD) and norbornene group-containing cycloolefins, in the presence of an effective amount of a metathesis polymerization catalyst and a co catalyst that is capable of crosslinking the unsaturated double bonds of the polymer and thereby increasing the crosslink density of the polymer and its T.sub.g, a process for making it, a process for increasing the T.sub.g of the molded article, and uses of the molded article with a high T.sub.g.

Abstract: Polymer scale deposition from a polymerization medium in which a monomer having an ethylenic double bond is polymerized, is prevented by conducting the polymerization in a polymerization vessel having a coating by applying a liquid comprising (A) an organic compound containing at least one member selected from the group consisting of a sulfonic acid group and a carboxylic acid group and having a molecular weight of 1000 or less and (B) a water-insoluble compound having an absorption band in the visible light range of 540 to 750 nm, the compounds (A) and (B) having been dissolved or dispersed in (C) an ester-based organic solvent, and having a pH of 3 or less; to the inner wall surfaces of said polymerization vessel. Polymer scale can be effectively prevented and polymeric products are barely colored.

Abstract: Emulsion polymers which are prepared by free-radical polymerisation of monomers in the presence ofa) polymers of the formulae ##STR1## wherein the radicals have the meanings given in the description, and b) low-molecular anionic emulsifiers,are outstandingly suitable as surface sizes for paper. They are distinguished by a low tendency to foaming and by a wide application spectrum.

Abstract: Novel polyacrylic acid resins are prepared by polymerizing H.sub.2 C.dbd.CHCO.sub.2 H, H.sub.2 C.dbd.CRCO.sub.2 X, or HRC.dbd.CHCO.sub.2 X, wherein R is an aliphatic or aromatic hydrocarbon, halogenated hydrocarbon, or sulfonated hydrocarbon of from C.sub.1 to C.sub.20, phenol, naphthol, sulfonated phenol, sulfonated naphthol, or a halogen, and X is hydrogen, alkyl, or a hydroxylated, ethoxylated, sulfonated, or halogenated aliphatic or aromatic hydrocarbon of from C.sub.1 to C.sub.20, sodium, potassium, ammonium, or quaternary amine, in the presence of aromatic sulfonic acid or its salt to form a polymer in which the sulfonated aromatic compound is covalently bound to the polymer. In an alternative embodiment, a textile processing or cleansing compound is included in the polymerization reaction along with the acrylic acid and aromatic sulfonic acid or its salt.

Abstract: This invention relates to a process for the living cationic polymerization of vinylic unsaturated compounds containing electron donating substituents resulting in polymers of narrow molecular weight distribution.

Abstract: This invention relates to the synthesis of a latex which can be formulated into coatings having improved flexibility and good water resistance. Coatings of this type are particularly useful in roof coating applications because they offer excellent flexibility, excellent ultra-violet light resistance, and good water resistance. The subject invention more specifically discloses a process for producing a neutralized latex that is useful in the manufacture of water reducible coatings which comprises:(1) free radical aqueous emulsion polymerizing, at a pH of less than about 3.5, a monomer mixture which comprises, based on 100 weight percent monomers: (a) from about 30 to about 70 weight percent vinyl aromatic monomers, (b) from about 25 to about 65 weight percent of at least one alkyl acrylate monomer, (c) from about 1 to about 5 weight percent of acrylic acid, and (d) about 0.4 to about 3 weight percent methacrylic acid, in the presence of about 0.2 to 0.

Abstract: A process for producing an aqueous resin dispersion is disclosed, which comprises dissolving a macromonomer having a radical polymerizable group at the terminal thereof and an oil-soluble radical polymerization initiator in a hydrophobic vinyl monomer copolymerizable with the macromonomer to form a solution, emulsifying the solution in an aqueous medium in the presence of an emulsifying agent selected from (A) an alkali sulfosuccinate anionic surfactant and (B) a surfactant comprising from 2 to 98% by weight of (i) an alkali sulfonate anionic surfactant other than (A) or (ii) an alkali sulfuric ester anionic surfactant, and from 98 to 2% by weight of a nonionic surfactant having an HLB value of 10 or more, and copolymerizing the macromonomer and the vinyl monomer at an elevated temperature. The aqueous resin dispersion has a high content of a graft polymer with a reduced content of unreacted macromonomer.

Abstract: A self-emulsifiable resin powder can be dispersed in water without utilizing additional surfactants or expending large amounts of mechanical energy. Such self-emulsifiable resin powders offer numerous distinct advantages over conventional latices. One of the most important benefits that is realized by utilizing self-emulsifiable resin powders is that they can be shipped dry which is the equivalent to shipping a latex with a 100 percent solids content. In other words, such self-emulsifiable resin powders eliminate the necessity for shipping water in latices. The self-emulsifiable resin powders disclosed herein also have the advantage of having low carboxyl contents and of being dispersible into aqueous systems which contain virtually no surfactants. These self-emulsifiable resins contain a relatively small proportion of repeat units which are derived from both acrylic acid and methacrylic acid.

Abstract: High molecular weight polymers of vinyl aromatic monomers are prepared by free radical polymerization in the presence of 5 to 5000 ppm of a soluble organic acid having pKa from 0.5 to 2.5.

Abstract: This invention relates to a process for the radical homo-or copolymerization of acrylonitrile with one or more copolymerizable monomers under reaction conditions such that the monomers are present predominantly in a gaseous form of an adsorbed form and polymerization of the monomers, which are presumably adsorbed, takes place in the solid phase (solvent-free polymerization) and results in pulverulent PAN-(co)polymers. The process is preferably carried out in the presence of small quantities of a mediator substance such as dimethylformamide which does not alter the pulverulent consistency of the PAN-polymers but leads considerably more rapidly and with much improved yields to freshly formed polyacrylonitrile polymers.

Abstract: High molecular weight polymers of vinyl aromatic monomers are prepared by organic hydroperoxide initiated free radical polymerization in the presence of 5 to 5000 ppm of a soluble organic acid having pKa from 0.5 to 2.5.

Abstract: A family of ionic polyacetylenes containing long sequences of conjugated double bonds in the backbone with ionic charges adjacent to or in conjugation with the backbone, and a synthetic process for preparing them, are disclosed. These polymers, which are soluble in many solvents including water, are mono- and di-substituted polyacetylenes that are extensively conjugated. The charge density and geometry of charge distribution depends on the number and nature of the substituents.

Abstract: Vinyl polymers, e.g., the homo- and copolyvinyl chlorides, are prepared in one or more stages, to a degree of conversion of at least 50%, by suspended emulsion polymerizing at least one vinyl monomer, e.g., vinyl chloride, said at least one monomer having dispersed therein finely divided droplets of an aqueous solution of at least one component of a polymerization initiating system, and wherein the amount of water in said aqueous solution constitutes at least 19%, and preferably at least 20% by weight of the at least one monomer.

Abstract: A process for the preparation of polymers which comprises forming an aqueous phase comprised of water and a surfactant; adding to the aqueous phase monomers; subsequently initiating polymerization of the monomers; thereafter adding a stabilizing component; and completing the polymerization.

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: Novel anionic polymeric hydrogels based on sulfonated amino aldehyde resins and a process for preparing such hydrogels are described. The hydrogels may include poly(N-vinyl 2-pyrrolidone) and other additives. Such hydrogels may be prepared by a four step process in which melamine and/or urea are reacted with formaldehyde, sulfonated, condensed to form a viscous gel and dried.

Abstract: The improvement in a process for the preparation of latexes of homo- and co-polymers of vinyl chloride, with particles having a mean diameter between 0.2 and 0.8 .mu.m and containing at least one organosoluble polymerization initiator, by polymerization in microsuspension of the corresponding monomer or monomers, according to which a fine dispersion of the monomer or monomers is formed in an aqueous medium containing at least one anionic emulsifying agent or at least one anionic emulsifying agent and at least one nonionic emulsifying agent, in the presence of 0.004 to 0.16% by weight; in relation to the weight of the monomer or monomers, of said initiator expressed as active oxygen and then the thus formed reaction medium is subjected to polymerization at the desired polymerization temperature (.theta..sub.1); the improvement comprising adding to the aqueous medium 2,6-ditert.

Abstract: The present invention relates to a process for preparing a polymeric resin which contains repeat units which are derived from maleic anhydride in an emulsion polymerization process which comprises polymerizing a vinyl aromatic monomer and an alkyl acrylate monomer in an aqueous medium in the presence of a styrene-maleic anhydride seed polymer which is neutralized with a tertiary amine. Such polymers, which contain repeat units which are derived from a vinyl aromatic monomer, an alkyl acrylate monomer, and maleic anhydride, are particularly useful as electrostatic image developing toner resins. For instance, resins, which are comprised of repeat units which are derived from styrene, butyl acrylate, and maleic anhydride, are particularly useful as toner resins.

Abstract: A novel process for the preparation of a readily dispersible, pourable dispersion powder comprising emulsion polymerizing in the presence of a free radial initiator a mixture of 1 to 50% by weight of ethylene and 99 to 50% by weight of an ethylenically unsaturated comonomer phase comprising at least one member of the group consisting of (a) 60 to 100% by weight of vinyl chloride, (b) 0 to 40% by weight of monoethylically unsaturated, oil-soluble monomers, (c) 0 to 10% by weight of monoethylenically unsaturated water-soluble monomers having functional groups and (d) 0 to 5% by weight of oil-soluble monomers that are monoethylenically unsaturated and have functional groups or are multiple ethylenically unsaturated and optionally a protective colloid and/or emulsifier at an ethylene pressure of 10 to 150 bar to obtain an aqueous dispersion of a vinyl chloride-ethyelene copolymer, optionally adding to the aqueous dispersion (e) 0 to 40% by weight, based on the VCE-polymer, of at least one water-soluble substance

Abstract: Storage-stable polychloroprene is obtained, using a polymerization initiator comprising a mixture of(1) a redox system comprising(a) a reducing agent selected from the group consisting of(i) sodium dithionite,(ii) formamidine sulphinic acid, and(iii) a mixture from (i) and (ii),(b) potassium peroxodisulphate as an oxidizing agent and, optionally,(2) sodium anthraquinone-.beta.-sulphonate as a co-activatorin the presence of oxygen, wherein from 10 to 90 by weight of the initiator are present at the commencement of polymerization and the remainder is added during the polymerization, and after a certain degree of conversion the reducing agent is the only component of redox system (1) which remains to be added.