Abstract: The present invention provides: an acrylic acid-maleic acid copolymer (or its salt) which is excellent in performances, such as Mg2+ scavengeability, clay dispersibility in the presence of Mg2+, inhibitability upon Mg(OH)2 scale, and inhibitability upon CaCO3 scale; and a production process for such a copolymer (or its salt). The present invention further provides a production process for an aqueous maleic salt solution with a low impurity content which has the advantage of easily giving the above copolymer (or its salt). The present invention still further provides uses of the above copolymer (or its salt) having the above excellent properties.

Abstract: A latex as a binder for nonwoven applications to form a permeable sublayer of personal hygiene articles. The latex is prepared by a process including the steps of (1) polymerizing a monomer mixture comprising styrene, itaconic acid, surfactant and water soluble free radical initiator to form a seed; (2) sequentially adding equal increments of a monomer mixture of styrene, butadiene and acrylic acid to the seed under emulsion polymerization conditions to form a styrene-butadiene-acrylic acid copolymer; and then (3) neutralizing the styrene-butadiene-acrylic acid copolymer to a pH of about 4.5 to 7 to form the latex.

Abstract: A process for reducing the odor emission of aqueous vinylaromatic/1,3-diene copolymer dispersions and of redispersion powders obtainable therefrom by drying, is by emulsion polymerization of a mixture containing at least one vinylaromatic and at least one 1,3-diene in the presence of one or more surfactant substances and optionally drying of the polymer dispersion obtained thereby. There are 0.01% to 15.0% by weight of one or more monomers of the branched or straight-chain alkyl esters having 1 to 8 C atoms in the alkyl radical of monounsaturated monocarboxylic or dicarboxylic acids and 0.01% to 15.0% by weight of one or more monomers based upon the vinyl esters of branched or straight-chain aliphatic carboxylic acids having 1 to 10 C atoms which are added in one step or in two successive steps toward the end of the polymerization, when the total content of free monomers in the aqueous copolymer dispersion is in the range from ≧0 to ≦20% by weight.

Abstract: A process for preparing aqueous polymer dispersions comprises first of all subjecting ethylenically unsaturated monomers to free-radical aqueous emulsion polymerization to prepare an aqueous dispersion of a polymer 1 having a glass transition temperature Tg1, then dissolving further, comparatively hard monomers in the dispersed particles of the polymer 1, and subsequently carrying out free-radical polymerization of said monomers dissolved in said particles.

Abstract: The present invention relates to a hydroxy-functional copolymer P, which is present as a dispersion and/or solution in water, and is obtained by successively carrying out process steps A-D: A) initially introducing a hydrophobic polymer containing hydroxyl groups into a reaction vessel, B) introducing an initiator component into that vessel, C) subsequently polymerizing a hydrophobic monomer mixture containing hydroxyl groups in that vessel and D) subsequently polymerizing a hydrophilic monomer mixture containing hydroxyl and acid groups in that vessel. The present invention also relates to a process for the preparation of copolymers P following the procedure previously set forth and to coating compositions containing these copolymers P and one or more crosslinking agents.

Abstract: A process for production of diene rubber polymers wherein, during production of a diene rubber polymer by emulsion polymerization, the polymerization is initiated using a portion of the starting material and the polymerization is continued with either continuous or intermittent dropwise addition of the remainder of the starting material during the polymerization, and wherein at least ½ of the total amount of the water and of the monomer in the starting material used is added dropwise during the polymerization, and the temperature of the dropwise added water and monomer is kept to at least 20° C. below the polymerization temperature. The process can produce industrially useful diene rubber polymer latexes at a high productivity rate.

Abstract: A polymeric latex prepared by aqueous emulsion polymerization of a monomeric mixture comprising styrene and butadiene in the presence of a seed polymer prepared by aqueous emulsion polymerization of styrene and a salt of 2-acrylamido-2-methylpropanesulfonic acid.

Abstract: The invention relates to a process for preparing substantially monodisperse crosslinked bead polymers useful as precursors for ion exchangers.

Abstract: The present invention provides: an acrylic acid-maleic acid copolymer (or its salt) which is excellent in performances, such as Mg2+ scavengeability, clay dispersibility in the presence of Mg2+, inhibitability upon Mg(OH)2 scale, and inhibitability upon CaCO3 scale; and a production process for such a copolymer (or its salt). The present invention further provides a production process for an aqueous maleic salt solution with a low impurity content which has the advantage of easily giving the above copolymer (or its salt). The present invention still further provides uses of the above copolymer (or its salt) having the above excellent properties.

Abstract: Fluoroelastomers having copolymerized units of vinylidene fluoride major monomer, at least one other fluorinated major monomer, and at least one cure site monomer are prepared in an aqueous suspension polymerization process using an initiator consisting essentially of a solution of an oil soluble peroxide in a water-soluble hydrocarbon solvent.

Abstract: A latex as a binder for nonwoven applications to form a permeable sublayer of personal hygiene articles. The latex is prepared by a process including the steps of (1) polymerizing a monomer mixture comprising styrene, itaconic acid, surfactant and water soluble free radical initiator to form a seed; (2) sequentially adding equal increments of a monomer mixture of styrene, butadiene and acrylic acid to the seed under emulsion polymerization conditions to form a styrene-butadiene-acrylic acid copolymer; and then (3) neutralizing the styrene-butadiene-acrylic acid copolymer to a pH of about 4.5 to 7 to form the latex.

Abstract: Poly(meth)acrylate dispersions, comprised of: (A) 50-90 wt. % methacrylic acid esters; (B) 5-30 wt. % acrylic acid alkyl esters; (C) 2-10 wt. % of another functionalized monomer; (D) 2-10 wt. % of a radically polymerizable carboxylic acid or a polycarboxylic acid or a partially esterified polycarboxylic acid; and (E) 0-40 wt. % of a monomer which is copolymerizable with components (A) to (D).

Abstract: General purpose inherently tacky acrylic pressure sensitive adhesive polymers formed of alkyl acrylates, vinyl esters, diesters of dicarboxylic acid and saturated carbocylic acids, having improved properties, a lower residual monomer content and a reduced polymerization time are formed by a sequential polymerization process in which 50 to 95 percent, typically 90 percent, of the monomers are incrementally added to a reactor as a first charge containing substantially all of the vinyl esters, preferably all of the diesters of dicarboxylic acid, the balance of the monomers being fed in a second incremental charge.

Abstract: The present invention provides a process for the production of a conjugated diene polymer having a controlled microstructure at a high polymerization activity in the presence of a metallocene type complex of compound of transition metal of the group V of the Periodic Table. A novel catalyst is provided comprising (A) a metallocene type complex of a transition metal of the group V of the Periodic Table, (B) an ionic compound of a non-coordinating anion and a cation, (C) an organic metal compound of the groups I to III and (D) water, wherein the molar ratio of (C)/(D) is from 0.66 to 5.

Abstract: A method for producing poly(p-t-butoxystyrene) by a polymerization reaction of p-t-butoxystyrene characterized in that p-t-butoxystyrene or a solution thereof is added little by little to a mixture of the reaction solvent and the polymerization initiator, and water content of the p-t-butoxystyrene or a solution thereof is in a range of 5-70 ppm, and according to the method, poly(p-t-butoxystyrene) having narrow molecular weight distribution can be produced securely, with easy reaction temperature control.

Abstract: An olefin polymer selected from the group consisting of a 1-butene homopolymer, a copolymers of 1-butene with propylene and a copolymer of 1-butene with an alkenyl hydrocarbon having 5 or more carbon atoms, wherein said olefin polymer is an amorphous polymer having a polystyrene-reduced number average molecular weight of 200,000 and substantially not having a melting point, an olefin polymerization catalyst obtained by contacting a specific transition metal compound(A), an organoaluminumoxy compound (B) soluble in an aromatic solvent and water (C), and a process for producing said olefin polymer with said catalyst.

Abstract: A polymer dispersion is prepared by free radical polymerization of an aqueous monomer emulsion by a process in which the monomer emulsion is prepared continuously at the rate of consumption.

Abstract: A process for preparing aqueous polymer dispersions comprises first of all subjecting ethylenically unsaturated monomers to free-radical aqueous emulsion polymerization to prepare an aqueous dispersion of a polymer 1 having a glass transition temperature Tg1, then dissolving further, comparatively hard monomers in the dispersed particles of the polymer 1, and subsequently carrying out free-radical polymerization of the monomers dissolved in the particles.

Abstract: Readily filterable and deodorizable aqueous dispersions of pressure-sensitive adhesive, especially for self-adhesive labels, having solids contents of more than 65%, can be prepared with readily reproducible properties by copolymerizing esters of acrylic and/or methacrylic acid in the presence of less than 50 ppm of inhibitor and, preferably, in the presence of from 0.01 to 5% by weight of reducing agent by a special emulsion technique. The highly concentrated pressure-sensitive adhesive dispersion, subsequently deodorized with steam, is free from coagulum and seediness.

Abstract: A process for forming a hydrophobically modified water soluble or water dispersible polymer by utilizing a micellar polymerization technique comprising the steps of: (1) providing a reaction medium including one or more water soluble or water dispersible monomers and one or more surface active agents or protective colloids; (2) incrementally adding one or more ethylenically unsaturated monomers having hydrophobic properties to said reaction medium; (3) initiating polymerization of said one or more water soluble or water dispersible monomers with said one or more ethylenically unsaturated monomers having hydrophobic properties; and (4) continuing polymerization of said one or more water soluble or water dispersible monomers with said one or more ethylenically unsaturated monomers having hydrophobic properties while incrementally adding said one or more ethylenically unsaturated monomers having hydrophobic properties to said reaction medium is provided.

Abstract: A PDMA polymer for a photosensitive resin composition. The PDMA polymer is obtained by polymerizing an acrylamide, N,N-dimetylacrylamide monomer, and a vinyl-type silane. The PDMA polymer having a molecular weight of 1,000,000.about.

Abstract: A process for forming a hydrophobically modified water soluble or water dispersible polymer by utilizing a micellar polymerization technique comprising the steps of: (1) providing a reaction medium including one or more water soluble or water dispersible monomers and one or more surface active agents or protective colloids; (2) incrementally adding one or more ethylenically unsaturated monomers having hydrophobic properties to said reaction medium; (3) initiating polymerization of said one or more water soluble or water dispersible monomers with said one or more ethylenically unsaturated monomers having hydrophobic properties; and (4) continuing polymerization of said one or more water soluble or water dispersible monomers with said one or more ethylenically unsaturated monomers having hydrophobic properties while incrementally adding said one or more ethylenically unsaturated monomers having hydrophobic properties to said reaction medium is provided.

Abstract: A polymeric material comprising at least first and second polymer parts, which first part has a number average molecular weight higher than that of the second part and which first and second polymer parts each comprise a respective polymer part derived from at least one ethylenically unsaturated monomer, is prepared by a process which comprises the steps of (1) preparing, by aqueous suspension polymerisation the first, higher molecular weight polymer part in the presence of a free radical initiator, but in the absence of a chain transfer agent to form a suspension of the first, higher molecular weight part and thereafter (2) preparing by aqueous suspension polymerisation the second, lower molecular weight part, which preparation step (2) is carried out in the presence of the suspension of the first, higher molecular weight part, a free radical initiator and a catalytic chain transfer agent (CCTA).

Abstract: The invention relates to a method of surface sizing cellulose based products such as paper, board and paper board. The method comprises applying to the surface of said products an aqueous dispersion of a copolymer obtainable by free-radical emulsion polymerization of a monomers mixture comprising at least one monomer selected from the group consisting of styrene and derivatives thereof; at least one monomer selected from the group consisting of esters of ethylenically unsaturated carboxylic acids and alkanols; and at least one monomer selected from the group consisting of ethylenically unsaturated carboxylic and sulfonic acids and salt thereof; optionally in combination with other ethylenically unsaturated copolymerizable monomers.

Abstract: A method for improving the flocculation of suspended solids in a Bayer process liquor in a primary settler stage. The method includes the step of adding to a primary settler feed a composition including water-continuous polymer, said polymer being hydrolyzable in a Bayer process liquor to an acid form, said acid form being an active red mud flocculent. A novel emulsion, and a polymerization technique for obtaining high molecular weight emulsions are also disclosed.

Abstract: The invention relates to a process and an apparatus for the microsuspension polymerization of vinyl chloride in vessels whose contents are agitated predominantly by natural convection where, in a reactor having a ratio of height H to diameter D of H/D 2, which is equipped externally or internally with a heat exchanger provided with water and connected to a pumped circulation system provided with water, the introduction of the cooling water takes place in the upper third of the heat exchanger and the cooling water is conducted downward and is conducted away in the lower third of the heat exchanger.

Abstract: In a gas phase olefin polymerization, an olefin is continuously fed to a fluid bed reactor in which a metallocene catalyst is present. At least one compound selected from water, alcohols and ketones is added in a specified amount simultaneously with the feeding of the olefin. Thus, an olefin polymer having a satisfactory drop second count index as defined by the below indicated formula is produced: ##EQU1## wherein t.sub.0 and t respectively represent a flow time measured in the flow test according to ASTM D-1775 of the olefin polymer obtained when none of the water, alcohols and ketones is incorporated in the reactor, and when at least one compound of water, alcohols and ketones is incorporated in the reactor. The flowability of the polymer formed in the reactor is excellent, so that blocking, bridging and the like do not occur during the gas phase polymerization. Thus, it is feasible to stably produce a (co)polymer having excellent particle properties in high yield for a prolonged period of time.

Abstract: An improved continuous process for the production of nitrile butadiene rubber with high bound acrylonitrile is provided wherein incremental amounts of butadiene monomer are continuously added in each of a plurality of reaction vessels to obtain a copolymer having superior environmental resistance and tensile strength properties.

Abstract: An aqueous polymer dispersion is prepared by free radical aqueous emulsion polymerization of a mixture of monomers having at least one ethylenically unsaturated group, which comprises at least 30% by weight of monomers having two conjugated ethylenically unsaturated double bonds, by a process in which the polymerization temperature is varied in the course of the free radical aqueous emulsion polymerization.

Abstract: A method for the solution or amulsion polymerization of ethylenically unsaturated monomers, styrene, and other free radical polymerizatable monomers in aqueous media in which a cobalt chain transfer agent is used which has both hydrolytic stability and solubility in water and in the organic phase with preferential solubility in the organic phase.

Abstract: A flocculant copolymer of acrylamide and Mannich base of acrylamide is provided which purifies and treats water and/or waste water, and/or sludge, and/or other contaminated liquids resulting from municipal discharges and industrial process effluents, as well as separating suspended and colloidal particles from liquids in industrial manufacturing processes. The copolymer has the general formula: ##STR1## wherein R.sub.1 is hydrogen or C.sub.1-4 alkyl groups, R.sub.2 and R.sub.3 are C.sub.1 to C.sub.8 alkyl groups and may be the same or different.It is prepared in two stage reaction. In the first stage Mannich base of acrylamide is produced by reacting acrylamide with formalin and dimethylamine or other secondary C.sub.1-8 -alkylamines: ##STR2## and in the second stage copolymer of acrylamide and Mannich base of acrylamide is produced by polymerizing in the presence of redox-initiator system. The mole ratio of acrylamide to Mannich base of acrylamide of 1:(0.05-0.

Abstract: A maleic acid-based copolymer is provided which has a weight-average molecular weight of 1,000 to 100,000, a calcium ion-capturability of 300 mgCaCO.sub.3 /g or higher calculated as calcium carbonate, and a clay-dispersibility of 1.2 or higher. Another maleic acid-based copolymer is also provided which has a level of adsorption to clay within the range of 20 to 90% and a calcium ion-stabilization degree constant of 4.0 or larger.

Abstract: A bimodal latex having high printing strength, reduced residue and a controlled polymer gel content which can be utilized for paper coating compositions and to a process for making the bimodal latex. The high strength bimodal latex, prepared by emulsion polymerization, includes in polymerized form open chain conjugated diene monomer, alkenyl aromatic monomer and at least one ethylenically unsaturated monomer selected from the group consisting of ethylenically unsaturated carboxylic acid and derivatives thereof.

Abstract: An aqueous polymerization method is disclosed for forming polymers containing, as polymerized units, at least one monomer having low water solubility, including the steps of:(1) complexing at least one monomer having low water solubility with a macromolecular organic compound having a hydrophobic cavity; and(2) polymerizing in an aqueous system from about 0.1% to about 100%, by weight of the monomer component, based on the total weight of the polymer, of the complexed monomer having low water solubility with from about 0% to about 99.9% by weight, based on the total weight of the polymer, of at least one monomer having high water solubility.The method is also useful for forming aqueous solution polymers having low water solubility.

Abstract: An saturated nitrile-conjugated diene copolymer obtained by copolymerizing acrylonitrile with butadiene in the presence of a free radical initiator and an alkylthiol compound as a molecular weight modifier. A part of the monomers is incorporated in a monomer charge before polymerization, and the remainder thereof is added in a polymerization mixture during polymerization. The alkylthiol compound has 12 to 16 carbon atoms, which include at least three tertiary carbon atoms, and further has a sulfur atom directly bound to at least one of the tertiary carbon atoms. The copolymer has a Mooney viscosity of 15 to 450 and a bound nitrile content of 10 to 60% by weight. The breadth (.DELTA.AN) of compositional distribution of the unsaturated nitrile in the copolymer is 3 to 20. The copolymer is used in combination with a sulfur-containing vulcanizer.

Abstract: A method for making a polymer includes adding a first portion of a colloidal stabilizer to an aqueous medium, adding a monomer mixture, said monomer mixture including a monomer charge and a second portion of colloidal stabilizer and said monomer charge including from about 40 parts by weight to about 70 parts by weight of a vinyl ester monomer per 100 parts by weight monomer charge and from about 30 parts by weight to about 60 parts by weight of a (C.sub.1 -C.sub.12)alkyl (meth)acrylate monomer per 100 parts by weight monomer charge, to the aqueous medium and polymerizing the monomers to form an emulsion of the polymer in the aqueous medium.

Abstract: A method for the production of a microsphere without use of a dispersion stabilizer is disclosed which permits the microsphere to be produced in the form of discrete particles readily treatable for purification. The method which produces this microsphere comprises the steps of dissolving in an organic solvent such as an alcohol a monomer mixture including an ethylenically unsaturated amide and 10 to 70% by weight, based on 100% by weight of said monomer mixture, of a cross-linking agent thereby preparing a mixed solution, keeping said mixed solution at a temperature in the range of from 30.degree. to 95.degree. C., and adding thereto at least one initiator selected from the group consisting of peroxide type initiators and azo type initiators in an amount such as to be contained therein at a final concentration in the range of from 1.times.10.sup.-5 to 8.times.10.sup.-2 mol/liter thereby inducing polymerization of said monomer mixture.

Abstract: A bimetallic catalyst produces broad or bimodal molecular weight distribution polyolefin resin whose composition depends on the ratio of the concentration of the two metals of the catalyst producing the HMW and LMW components. The bimetallic catalyst produces a broad/bimodal MWD resin whose HMW and LMW components depend on the relative productivity of each of the transition metal sites of the catalyst. Water and/or carbon dioxide are cofed to the polymerization reactor at levels necessary to modify the weight fractions of the HMW and LMW components, thus achieving a target molecular weight distribution, MWD. The invention allows the resin MWD to be adjusted in the reactor. The weight fraction of the high molecular weight component decreases with the addition of the water and or the carbon dioxide and the FI of the overall product increases with a decrease in the HMW component weight fraction in the product.

Abstract: This invention discloses a process for preparing a latex which is particularly beneficial for utilization in manufacturing high performance masking tape, which includes the sequential steps of (1) terpolymerizing a vinyl aromatic monomer, an alkyl acrylate monomer, and an alkyl propenoic acid monomer in an aqueous polymerization medium by free radical polymerization to produce a seed polymer latex; (2) neutralizing the seed polymer latex to a pH of about 6 to about 9 by the addition of an alkali; (3) adding additional vinyl aromatic monomer and alkyl acrylate monomer to the neutralized seed polymer latex; and (4) allowing the additional vinyl aromatic monomer and alkyl acrylate monomer to polymerize in a second polymerization step to a solids content of about 30% to about 50% to produce the latex which is particularly beneficial for utilization in manufacturing high performance masking tape.

Abstract: A textile sizing composition comprising one or more aqueous-based dispersions containing between about 15 and about 50 percent by weight solids wherein said solids comprise one or more polymers derived from one or more ethylenically unsaturated monomers, said solids having an average particle size of less than 100 nanometers is disclosed.

Abstract: An in situ process for the preparation of resin particles comprising: preparing a seed particle latex by aqueous emulsion polymerization of a first mixture comprised of at least one monomer, an optional chain transfer agent, and a water soluble free radical initiator, wherein the reaction of the free radical initiator and monomer produces oligomeric radicals which provide in situ stabilization to the resulting first generation seed particles; optionally diluting the first seed particle latex with water; heating and starve feed adding to the first generation seed particles a second mixture comprised of at least one monomer, an organic soluble free radical initiator, an optional chain transfer agent, an optional water soluble free radical initiator, and an optional surfactant to form a third mixture comprised of second generation seed particles; heating and starve feed adding to the second generation seed particles additional said second mixture to form a fourth mixture comprised of third generation seed partic

Abstract: Simultaneous control of the molecular weight and the molecular weight distribution in the production of toner resins can be accomplished by using a starve fed emulsion polymerization process, which includes: selecting a desired molecular weight and molecular weight distribution of the polymer resin; determining a starve fed fraction to achieve the desired molecular weight and molecular weight distribution; and charging a reaction vessel with a chain transfer agent and a first monomer emulsion, and polymerizing monomer in the first monomer emulsion while simultaneously adding to the reaction vessel additional monomer, in the form of a second monomer emulsion, and additional chain transfer agent. The resins thus produced may be used in dry toners, liquid developers and inks suitable, for example, for ink jet applications.

Abstract: In a process for the microsuspension of emulsion polymerization of vinyl chloride using a polymerization apparatus equipped with an agitator the improvement where the ratio (H/D) of the effective height (H) of the apparatus to the effective inner diameter (D) of the apparatus is 4 or more.

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 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: A process for emulsion polymerization to form a latex having a particle size greater than about 0.5 micrometers by charging to a reaction vessel under agitation a reaction mixture including water, emulsifiers at an initial concentration slightly greater than or equal to the critical micelle concentration, a protective colloid, ethylenically unsaturated monomers, and an ionically balanced combination of an anionic and a cationic water soluble free radical initiator or a nonionic initiator; reacting the mixture to form an emulsion of polymerized monomer; and adding additional monomer, emulsifier, and protective colloid and a water soluble chain transfer agent to the reactor while continuing to agitate the mixture under conditions such that the emulsifier concentration does not exceed that at which new polymeric nuclei are formed.

Abstract: A process for preparing a porous and water-absorbent resin which includes dispersing an aqueous solution containing at least one .alpha.,.beta.-unsaturated carboxylic acid monomer, its alkali metal salt or its ammonium salt in a hydrophobic organic solvent, and conducting a reversed phase suspension polymerization by using a water-soluble radical polymerization initiator, while distilling away the hydrophobic organic solvent together with water. A porous and water-absorbent resin having excellent absorbency and a remarkably improved rate of water absorption can be easily and efficiently obtained on an industrial scale.

Abstract: A suspension polymerization process for the preparation of a polymeric material formed from at least two monomers, a non-gaseous monomer and a gaseous monomer. The composition of the beads or particles of the polymeric material is controlled by adding gaseous monomer to the vapor phase after polymerization of about 5% to about 90% by weight of the non-gaseous monomer or by removing a portion or substantially all of the gaseous monomer in the vapor phase before polymerization of about 70% by weight of the gaseous monomer in the aqueous suspension, or a combination thereof.

Abstract: A process for forming a stable and processable polymer comprised of methacrylonitrile (10 to 80 percent) and acrylonitrile (20 to 90 percent) by controlling the ratio of the monomers in the reaction mixture.

Abstract: A process for producing a toner resin by a two-step suspension polymerization process, which entails preparing a polymer of high molecular weight having a weight average molecular weight of greater than about 350,000 from at least one monomer having a polymerizable vinyl group using a compound having at least three t-butyl peroxide groups in one molecule, as a polymerization initiator, and then preparing a low molecular weight polymer in the presence of the high molecular weight polymer. A toner having an excellent fixing property and offset resistance can be obtained from the above resin.