JPS6259137B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to latex compositions and methods of making such latexes. Polymer particles comprising latex have stable, pH-independent ions chemically bound at or near the particle surface. Latexes require means of colloidal stabilization in aqueous media. Colloidal stabilization can usually be carried out by surfactants, which are usually anionic or cationic but may also be in mixtures with non-ionic, especially anionic or cationic surfactants. . Although surfactants contribute to the necessary colloidal stability, they interfere with the coating performance of latexes in limited amounts, and even below the amount that provides the desired stability. As described in U.S. Pat.
There are other methods of copolymerizing ionic monomers and small proportions of ionic monomers. However, this method requires a special blend of monomers and a special polymerization method. Although this process results in a latex containing little or no surfactant, varying amounts of water-soluble products are formed during this operation and remain in the product. U.S. Pat. No. 3,236,820 describes the preparation of water-soluble cationic polymers by reaction of anionic latexes of vinyl chloride-benzyl polymers with sulfides. Starting from an anionic emulsion, converting the polymerized vinylbenzyl chloride units on the particles to cationic groups causes destabilization of the latex. If the proportion of vinylbenzyl chloride units in the polymer is not high enough to render the converted polymer water soluble, the latex will coagulate. The present invention consists of a water-insoluble, non-ionic organic polymer core surrounded by a thin layer of copolymer having chemically bonded PH-independent cationic groups on or near the outer surface of the particle. This includes latexes having constituent particles with a cationic charge attached to them. Such latexes contain ethylenic unsaturation under emulsion polymerization conditions on the particle surface of a non-ionic organic polymer latex that is slightly cationic due to the presence of adsorbed cationic surfactants. It is obtained by copolymerizing activated halogen monomers. In addition, the precursor latex is a copolymer particle of an ethylenically unsaturated activated halogen monomer and an ethylenically unsaturated activated halogen-free non-ionic monomer as a polymer component, and the activated halogen is present throughout the particle. The particles may be uniformly or appropriately distributed. Both types of latexes derive much of their colloidal stability by reacting with nonionic nucleophiles to create pH-independent cationic groups chemically bonded to or near the outer surfaces of the constituent particles. forming a latex with constituent particles consisting of a water-insoluble, nonionic organic polymer core surrounded by a copolymer layer containing sufficient amounts to provide water but insufficient to render the polymer water-soluble. do. More specifically, in one aspect, the present invention provides the following:
The present invention provides a method for producing a cationic latex characterized by comprising the steps (a), (b) and (c). (a) a latex consisting of a nonionic organic polymer core is used as a starting material; (b) a nonionic ethylenically unsaturated monomer with an activated halogen and a nonionic nonionic polymer without an activated halogen; (a) above with a thin capsule layer of a water-insoluble organic polymer with an ethylenically unsaturated monomer.
producing a latex comprising copolymer particles encapsulating a nonionic organic polymer core with an activated halogen uniformly or randomly distributed throughout the particles; and in an amount of 0.01 to 0.5 milliequivalents per gram of latex particles and 0.4 to 2.5 milliequivalents per gram of copolymer in the capsule layer.
and (c) the latex produced in (b) above is heated between 0°C and 80°C.
Consists of polymer particles with pH-independent cationic groups chemically bonded to the particle surface by reacting with a low molecular weight, water-stable, non-ionic nucleophyl group that can diffuse into an aqueous medium at a temperature of Manufacture latex. In another aspect of the present invention, a nonionic ethylenically unsaturated monomer having a nonionic organic polymer core and an activated halogen and a nonionic ethylenically unsaturated monomer without activated halogen are provided. consisting of a thin capsule layer of a water-insoluble organic copolymer with a saturated monomer and the activated halogen in an amount of 0.01 to 0.5 milliequivalents per gram of constituted latex particles and copolymer in the capsule layer. an aqueous colloidal dispersion of cationic structured latex particles derived from polymer particles present in an amount of 0.4 to 2.5 milliequivalents per gram of combined;
It provides: In one embodiment, the manufacture of the products of the invention requires a starting latex comprising solid polymeric particles colloidally dispersed in water, the composition of which and the method of preparation thereof are known per se; The particles of the starting latex are substantially modified to be encapsulated with a copolymer of an ethylenically unsaturated activated halogen monomer and an ethylenically unsaturated activated halogen-free monomer. It is something. The resulting latex contains colloidally dispersed particles with reactive halogen groups at or near the surface of the particles. Such a latex can then be reacted with a low molecular weight non-ionic nucleophilic compound to produce a latex with polymer particles having pH-independent cationic groups chemically bonded to the particle surface. . The colloidal stability of the latex is thereby improved and other advantageous properties are obtained. There are many latexes that can serve as raw latexes for making activated halogen-containing latexes, and their compositions are not limited to a narrow range. Such latexes are made by methods well known in the art. Although preformed latexes substantially free of residual monomer can be used, this raw latex may still have some residual monomer and free radicals upon addition of the activated halogen monomers as a first step in the production of latex products. It can be conveniently produced by emulsion polymerization. The raw latex or ingredients and the process for preparing this latex are selected from known latex compositions that are substantially free of anionic groups and/or free of anionic surfactants adsorbed or bound to the polymer particles forming the latex. It will be revealed. The latex may be somewhat cationic due to the presence of some cationic surfactant. For best results, the raw latex should not contain enough surfactant to create new particles when monomer is added. The composition of the polymeric components of the raw latex also influences the properties of the final product since it constitutes a major portion of the total product volume. The choice is therefore made in part by the desired polymeric properties known to be possessed by prior art materials to provide the properties ascribed to the enveloped components of the present invention. Thus, by way of example, but not limitation, there are applications (such as for plastic pigments) where a raw latex that forms a film at room temperature is selected for the main part of the product, but a raw latex that does not form a film is selected. Common raw latexes have particle sizes of about 500 to about 10,000 Å, preferably about 800 to about 3,000 Å. If the product is to be used in a manner that requires commonly recognized properties, such as low electrolyte concentrations, this property will be considered when selecting the raw latex and ingredients used to perform the following operations. This selection is within the knowledge of the art and is not considered inventive content of the parent compositions and methods of the present invention. Typically, the raw latex is obtained by emulsion polymerization of one or more monomers. This monomer is represented by the same monomer for copolymerization with the activated halogen monomer listed below. Under ordinary emulsion polymerization conditions, a substantial polymerization reaction cannot be obtained at an industrially usable rate as with isobutene, or with stereospecific polyisoprene, stereospecific polybutadiene, etc. Because a specific type of polymerized monomer is desired, the raw latex for encapsulation consists essentially of polymers that cannot be readily produced by emulsion polymerization reactions. Typical preformed polymers are monoolefins having 2 to 20 carbon atoms, especially carbon Polymers and copolymers of monoolefins having up to 8 atoms. Particularly common types are various ethylene/propylene copolymers. Examples of other polymers that can be a component of the raw latex for encapsulation include alkyd resins, block and graft copolymers, such as styrene/butadiene grafts and block copolymers; epichlorohydrin and bisphenol A reaction products such as epoxy resins; and heat-setting vinyl ester resins, e.g. There are about equimolar amounts of reaction products with Methods of making the above polymers and converting them into latexes are known and are not within the scope of this invention. In one method for preparing a latex suitable for subsequent reactions according to the process of the invention, an activated halogen monomer or a mixture of such monomers is added to the reaction mixture of the raw latex before all of the monomers have been converted to polymer. or activated halogen monomers together with one or more hydrophobic monomers to a raw latex essentially free of residual monomers. Polymerization is initiated and substantially completed to envelop the raw latex particles in a thin copolymer layer of ethylenically unsaturated activated halogen monomer. Other latexes suitable for reaction according to the process of the invention are obtained by direct emulsion polymerization of ethylenically unsaturated activated halogen monomers and ethylenically unsaturated activated halogen-free non-ionic monomers. I can do it. A latex is thus obtained containing copolymerized particles containing activated halogen homogeneously or arbitrarily dispersed throughout the particles. The activated halogen monomers of either type of latex must be sufficiently activated to react at a suitable rate after polymerization with a subsequently added nucleophile, but are not easily activated in an aqueous medium. It must not be so reactive as to hydrolyze. Suitable monomers are ethylenically unsaturated benzyl chloride or bromide monomers, ethylenically unsaturated aliphatic iodide monomers and ethylenically unsaturated aliphatic bromide monomers. Particularly preferred activated halogen monomers are vinylbenzyl chloride, vinylbenzyl bromide, 2-
Chloromethylbutadiene, vinyl bromide and bromoalkyl acrylate or bromoalkyl methacrylate, especially 2-bromoethyl acrylate or 2-bromoethyl methacrylate. The activated halogen monomers are oil-soluble, readily polymerize in emulsions, do not interfere with free radical polymerization reactions, and diffuse into latex particles at a sufficient rate in the aqueous medium of the latex. Hydrophobic ethylenically unsaturated monomers that can be copolymerized with activated halogen monomers are non-ionic ethylenically unsaturated monomers that polymerize in aqueous emulsions to form water-insoluble polymers. You can choose from widely known classes of mercury. These monomers are well known in the art and representative examples are illustrated below. Non-ionic ethylenically unsaturated monomers include, but are not limited to: hydrocarbon monomers such as styrenic compounds, such as styrene, α-methylstyrene, ar- Methylstyrene, ar-ethylstyrene, α,ar-dimethylstyrene, ar,ar-dimethylstyrene, and t-butylstyrene; conjugated dienes such as butadiene and isoprene; modified carbons with non-ionic substitutions Hydrogen monomers such as hydroxy-styrene, methoxystyrene, and cyanostyrene; unsaturated alcohol esters such as vinyl acetate and vinyl propionate; unsaturated ketones such as vinyl methyl ketone and methyl isopropenyl ketone; Saturated ethers, such as vinyl ethyl ether and vinyl methyl ether; and acrylic esters, such as methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, 2-
Non-ionic derivatives of ethylenically unsaturated carboxylic acids such as ethylhexyl acrylate and lauryl acrylate; methacrylic esters such as methyl methacrylate, ethyl methacrylate; maleic esters such as dimethyl maleate, such as diethyl maleate, and dibutyl maleate; fumaric acid esters,
For example dimethyl fumarate, diethyl fumarate and dibutyl fumarate and itaconic acid esters such as dimethyl itaconate, diethyl itaconate and dibutyl itaconate; and nitriles such as acrylonitrile and methacrylonitrile. Non-ionic monomers containing unactivated halogens such as monochlorostyrene, dichlorostyrene, vinyl fluoride and chloroprene, although not the preferred types, can also be used. Non-ionic monomers that form water-soluble homopolymers, such as acrylamide, methacrylamide, hydroxyethyl acrylate, and hydroxyethyl methacrylate, may also be hydrophobic in small amounts, up to about 10% based on the amount of hydrophobic monomer. Can be mixed with monomers. A "PH-independent group" used as an ionic group means a group that is primarily ionizable over a wide PH range, for example 2-12. "Non-ionic" as used herein for monomers means that the monomers are not themselves ionic or
This means that it does not become ionic due to a simple change in pH. For example, monomers containing amine groups are non-ionic at high pH, but when a water-soluble acid is added,
Lowers pH and produces water-soluble salts; does not contain such monomers. In order to carry out the polymerization reaction of activated halogen monomers in an embodiment in which activated halogens are present inside the particles, the ratio of the monomer to the total polymer in the latex must be adjusted to an excess of the amount of latex particles present. should be kept low throughout the operation to avoid swelling. If the swelling is severe, ie, the monomers in the polymer are too dissolved, some polymerization will occur inside the particles.
The activated halogen monomer is added to the raw latex over a short period of time or in one or more portions. Optionally, a hydrophobic monomer or mixture thereof without activated halogen may also be added, usually in admixture with the activated halogen monomer. In order to avoid hydrolysis of the activated halogen monomer, the polymerization reaction is preferably carried out at a low temperature that provides a practical polymerization rate.
Such a temperature range is from about 0°C to about 80°C,
About 50 to about 70°C is preferred. Unless the raw latex is made in situ, a reaction initiator (catalyst) is added to activate the latex particle surface, ie, to provide a steady state concentration of free radicals. If necessary, a reaction initiator may be added continuously after the addition of the monomers, especially when a redox system is used. The polymerization reaction continues until the monomers are substantially completely copolymerized. The product obtained by the above method is a raw latex particle having a thickness ranging from a monolayer of copolymer to about 100 Å and surrounded by a layer consisting of a functionalized polymer with activated halogen groups on the outer surface of the polymer. A latex of colloidally dispersed polymer particles having a particle size of about 500 to about 10,000 Å. The amount of activated halogen monomer copolymerized in the capsule layer of the latex of the constructed particles ranges from about 0.01 to about 1.4 per gram of total polymer in the latex.
Milliequivalents, preferably about 0.04 to about 0.5 milliequivalents. However, the amount of hydrophobic monomer copolymerized with the activated halogen monomer is sufficient such that the copolymerized activated halogen monomer does not exceed 3.0 milliequivalents per gram of polymer in the capsule layer or cap. There must be. The proportion of activated halogen monomer is inversely proportional to the particle size of the encased latex and is also inversely proportional to the molecular cross-sectional area of the activated halogen monomer. Therefore, a starting latex of minimum particle size with minimum amount of activated halogen monomer cannot be used. The initiators used in the polymerization reaction of activated halogen monomers are of the type that generates free radicals and are preferably monooxygen compounds, such as inorganic peroxides such as hydrogen peroxide; cumene hydroperoxide and Organic hydroperoxides such as t-butyl hydroperoxide; organic peroxides such as benzyl peroxide, acetyl peroxide, lauroyl peroxide, peracetic acid and perbenzoic acid - in some cases ferrous compounds, heavy activated with water-soluble reducing agents such as sodium sulfite or hydroxylamine hydrochloride and free-radical generating substances such as 2,2'-azobis-isobutyronitrile. Organic hydroperoxides and 2,2'-azobis-isobutyronitrile are preferred. The surfactants used either in the raw latex or as stabilizing additives for latex products are cationic surfactants or non-ionic surfactants or mixtures thereof. Cationic surfactants include aliphatic amines, especially salts of fatty amines, quaternary ammonium salts and hydrates, aliphatic amides derived from disubstituted diamines, and fatty acids of pyridinium compounds. There are classes of chain derivatives, ethylene oxide condensation products of fatty amines, sulfonium compounds, isothioureonium compounds and phosphonium compounds. Specific examples of cationic surfactants are dodecylamine acetate, dodecylamine hydrochloride, tetradecylamine hydrochloride, hexadecylamine acetate, aryldimethylamine citrate,
Octadecylamine sulfate, dodecylamine lactate,
Cetyltrimethylammonium bromide, cetylpyridinium chloride, ethanolated alkylguanidine amine complex compound, stearyldimethylbenzylammonium chloride, cetyldimethylamine oxide,
Cetyldimethylbenzylammonium chloride, tetradecylpyridinium bromide, diisobutylphenoxyethoxyethyldimethylbenzylammonium chloride, 1-(2-hydroxyethyl)-
2-(pentadecyl and pentadecyl mixture)-2-
Imidazoline, resin amine ethoxylate, olelimidazoline, octadecylethylmethylsulfonium methyl sulfate, dodecyl-bis-β-hydroxyethylsulfonium acetate, dodecyl-benzyldimethylsulfonium chloride, dodecyl-benzyltrimethyl sulfonium chloride Onium, S-p-dodecylbenzyl chloride-N,N,
N′,N′-tetramethylisothiouronium, etc. Typical non-ionic emulsifiers (surfactants) are alkylene oxides such as ethylene oxide, propylene oxide, or butylene oxide, long-chain aliphatic alcohols, long-chain fatty acids, alkylated phenols, and long-chain alkyl mercaptans. , long-chain alkyl primary amines, such as acetylamine, compounds formed by reaction with alkylene oxides reacting in high proportions, such as 5 to 20 or even 50 moles per mole of co-reactant. It is. Similarly effective compounds are reaction products of polyethylene glycol and long-chain fatty acids, such as monoesters such as glycerol monostearate, sorbitan trioleate, and polyglycol esters of long-chain carboxylic acids and polyhydric alcohols. Partial and complete esters. The “long chain” mentioned above usually refers to 6 carbon atoms.
It means an aliphatic group having from 20 to 20 or more. Preferred surfactants are those with cationic groups independent of pH, particularly preferred where the cationic groups are sulfonium, sulfoxonium, isothiouronium or reducible quaternary nitrogen groups, such as pyridinium, isoquinolinium. and fugitive surfactants such as quinolinium cationic surfactants. The above-described latex, which contains particles of raw latex surrounded by a relatively thin film of a copolymer of an activated halogen monomer and a hydrophobic ethylenically unsaturated monomer, is then treated with a low-molecular-weight non-carbon material that can diffuse into the aqueous phase. It can be reacted with ionic water-stable nucleophilic compounds to produce polymer particles with pH-independent cationic groups, ie, onium ions chemically bound to the particle surface. Normal particles are approximately spherical. In addition, in copolymer latexes that have activated halogens uniformly or at arbitrary positions throughout the polymer particles forming the latex, only the activated halogens on or near the surface of the particles react with the nucleofoil. If the composition and conditions are selected so as to produce a latex of cationic structured particles, it is possible to react with non-ionic nucleophyl. The amount of activated halogen in the copolymer should not exceed about 3.0 mcg/g.
Because the reaction rate of activated halogens at or near the particle surface in such copolymers is considerably faster than that of halogens inside the particle, the kinetic data indicate when a thin layer near the surface has reacted. Will.
As the nucleophyl reacts with the copolymer having a larger amount of polymerized activated halogen monomer throughout the particle, swelling of the particle occurs, and the reaction within the particle progresses rather easily, resulting in structured particles. It is difficult to adjust the reactions that result, and the same good results cannot be obtained. For each active halogen reacting with the non-ionic nucleophyl, there is one charge attached to the polymer and one halogen ion is released. In the reaction of the neucleophyl with a latex of activated halogen constituent particles or a latex in which the activated halogen is dispersed throughout the latex particles, the amount of halogen reacted per gram of polymer ranges from about 0.01 to about 20% per gram of polymer.
The amount is such that it has a charge of 0.5 milliequivalent. A range of about 0.04 to 0.035 milliequivalents of charge per gram of polymer is preferred. However, in the thin reaction layer near the particle surface, the amount of bonded charge is about 0.4 to about 2.5 milliequivalents for each gram of polymer in the layer. Nucleophilic compounds that can be used in the practice of this invention are stable in aqueous media with a heteroatom as the center of nucleophilicity in which all covalent bonds of the heteroatom are to carbon atoms. It is a nucleophyle containing non-ionic carbon that can be diffused. Nucleophilic compounds which may be conveniently used in the practice of this invention are the following types of compounds, sometimes referred to as Lewis bases: (a) monobasic aromatic nitrogen compounds; (b) tetrabasic compounds; (lower alkyl)thioureas, (c) R ₁ -S-R ₂ in which R ₁ and R ₂ are individually lower alkyl, hydroxy lower alkyl, or R ₁ and R ₂ have 3 to 5 carbon atoms; 1 bonded as an alkylene group, in which R ₂ and R ₃ are individually bonded together as lower alkyl or hydroxy lower alkyl, or 1 alkylene group having 3 to 5 carbon atoms, and R ₁ is lower alkyl, aralkyl or aryl, provided that R ₂ and R ₃ are both alkylene groups, R ₁ is lower alkyl or hydroxy lower alkyl, and wherein R ₁ , R ₂ and R ₃ are individually lower alkyl, hydroxy lower alkyl or aryl. As used herein, "lower alkyl" refers to alkyl having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, and isobutyl. Representative specific nucleophilic compounds include pyridine, quinoline, isoquinoline, tetramethylthiourea, tetraethylthiourea, hydroxyethylmethyl sulfide, hydroxyethylethyl sulfide, dimethyl sulfide, diethyl sulfide, di-n-propyl sulfide,
Methyl-n-propyl sulfide, methylbutyl sulfide,
Dibutyl sulfide, dihydroxyethyl sulfide, bis-hydroxybutyl sulfide, trimethylene sulfide,
thiacyclohexane, tetrahydrothiophene,
N-methyl-piperidine, N-ethylpyrrolidine, N-hydroxy-ethylpyrrolidine, trimethylphosphine, triethylphosphine,
Tri-n-butylphosphine, triphenylphosphine, trimethylamine, triethylamine, tri-n-propylamine, tri-isobutylamine, hydroxy-ethyldimethylamine, butyldimethylamine, tri-hydroxyethylamine, triphenylphosphine and N,N,N-dimethylphenethylamide. To carry out a reaction between a nucleophilic compound and latex particles having activated halogens chemically bonded to the particle surface, the nucleophilic compound is added to the latex, either neat or in the form of a solution, while gently stirring the latex. Add with . Gentle stirring is continued for the duration of the reaction, and sometimes even after the compound has been dispersed in the latex, and then stopped. The reaction is conveniently carried out at room temperature, although temperatures from 0°C to about 80°C can be used. This reaction occurs spontaneously at a rate based on the reactivity of the activated halogen and the nucleophyl. It is advisable to allow the reaction to proceed until the product is largely colloidally stable due to the resulting chemically bound cationic groups. For less reactive substances, small amounts of iodide ions are used to accelerate the reaction, but usually no catalyst is required. When the reaction reaches the desired point, excess nucleophyl is usually removed by standard methods such as dialysis, vacuum stripping and steam distillation. Other pH-independent cationic groups can be substituted for the cationic groups chemically bonded to the latex particles by further reaction with such cationic groups. For example, a latex of cationic constituent particles having sulfonium groups chemically bonded to the constituent particles at or near the particle surface may be heated with hydrogen peroxide at a temperature of about 20 to 80°C, preferably at room temperature, for a sufficient period of time. The reaction can oxidize some or all of the sulfonium groups to sulfoxonium groups. This treatment also reduces latex odor. This oxidation reaction is best performed using an excess of hydrogen peroxide per mole of sulfonium groups, for example from 2 to 10 moles. It is advantageous to react an activated halogen latex containing a length of activated halogen which is to be converted to a bond charge when the product is used in metallization. In this way, all activated halogens are converted to cationic groups, and there is no bound activated halogen in the product. The cationic latex of the present invention has considerably improved chemical and mechanical stability. However, in many applications, such as coating hydrophobic substrates, latexes stabilized solely by charges chemically bonded to the particle surface have surface tensions that are too high to provide good wetting properties to hydrophobic surfaces. In such cases, a small amount, such as about 0.01 to 0.1 meg per gram of polymer, of a conventional cationic or non-ionic surfactant may be added to the latex. Yet in other applications the presence of even small amounts of water-soluble surfactants is detrimental. The latex of the present invention is also very advantageous for such applications. A sufficient amount of charge is chemically bonded to the particle surface to provide colloidal stability and, if necessary, to remove water-soluble substances from the latex and to improve the cationic reactivity and colloidal stability of the latex. Extensive dialysis or ion exchange can be used to reverse the ionization while maintaining the ion content. A simple test is suitable for checking the shear stability of latex. Put a drop of latex on your palm and rub it back and forth with your fingers. When latex is rubbed, it gradually dries to form a film.
Unstable latexes usually coagulate by rubbing one to three times before drying. A stable latex can be rubbed more than five times before solidifying. The latex, which withstands 20 rubs, is very stable and can be rubbed dry before setting up. The friction test correlates with a more complex test in which a drop of latex is sheared in a cone and plate viscometer (Lord Visco rotational viscometer). Friction tests show that the latex is extremely stable and does not solidify.
Can shear for more than 15 minutes at 194r.pm. The particles of the latex of the present invention, i.e., the raw latex and the product, are generally approximately spherical and have a particle size of about 500 to about 10,000.
It has a particle size (diameter) of Å. The following examples are illustrative of how to carry out the invention and are not to be considered as limiting the invention. All parts and percentages are by weight unless otherwise noted. Unless otherwise specified, the particle size in the examples indicates the average particle diameter obtained by a light scattering method. Example A thermoplastic acrylic latex was produced in the following manner. A monomer mixture was prepared by mixing 1072 g of ethyl acrylate and 528 g of methyl methacrylate, and to this was added 24 g of dodecanethiol and t-hydroperoxide.
A monomer feed solution was prepared by adding 5 g of 82.7% butyl solution. To 750 g of a surfactant solution previously prepared by stirring 710 g of water and 40.0 g of a 25 active solution of dodecylbenzylsulfonium chloride for 2 hours under nitrogen flow, 25 g of the monomer feed solution was added, followed by hydroxylamine hydrochloride. The reducing agent solution, prepared in advance by diluting 9 g with 500 g of deionized water, was added at a rate of 7.67 g per hour to approximately 2
Seed latex was made by continuous addition using a pump. 55 g of monomer feed liquid per hour for this type of latex
At the same time, a reducing agent stream of the same addition rate and composition as in the seed latex was added and the reaction mixture was mixed with 400 g of deionized water and a 25% active solution of dodecylbenzylmethylsulfonium chloride.
20g of pre-made surfactant liquid per hour from 100g
mixed by pump at the same time. After 20 hours, the conversion had progressed to about 85%, so continuous addition was stopped, 15 g of vinylbenzyl chloride was added, and the reaction was continued for an additional 2 hours. The temperature was maintained at 50°C during the reaction. The latex (C-1) thus obtained had a solid content of 47.6%, a pH of 2.8,
It contains a polymer with a particle size of 1250 Å and a molecular weight of 74000, and its chloride ion content is per gram of polymer.
It was 0.113 milliequivalent. Part of latex (C-1) is added with water to reduce solid content.
Per 100 parts of diluted latex after diluting to 23.8%
2.12 parts of trimethylamine were added with gentle stirring and the resulting mixture was left at room temperature for 5 days. The latex obtained (IA) has a total charge per gram of polymer.
0.242 mequivalents, of which 0.129 mequivalents were from quaternary ammonium groups attached to each gram of polymer in the latex. The other part of latex (C-1) was treated as described in Example 2. However, trimethylamine
2.24 parts of dimethyl sulfide was substituted. The resulting latex (IB) had a total charge of 0.237 milliequivalents per gram of polymer, of which 0.124 milliequivalents were from sulfonium groups attached to each gram of polymer in the latex. EXAMPLE A latex was made by a quasi-continuous method as described below. The various compositions were made by adding in separate streams. First aqueous solution: Mix 8.75 g of 85.5% phosphoric acid aqueous solution and 1000 g of water, add enough ammonium hydroxide to make the pH of the solution 5, add 20 g of dodecylbenzyldimethylsulfonium chloride (activity basis), and add water. liquid
Sufficient ammonium hydroxide was added to give 2000 g and a pH of 5. Continuous emulsifier stream Dodecylbenzyldimethylsulfonium chloride
Water was added to 125g (activity basis) to make 1000g. Continuous initiator flow 27.5 g t-butyl hydroperoxide (activity basis)
500g of aqueous solution containing. Continuous reducing agent stream 500g containing 14g hydroxylamine hydrochloride
aqueous solution. 1st monomer liquid butadiene 1500g styrene 1200g butyl acrylate 300g dodecanethiol (chain transfer agent) 3g 2nd monomer liquid butyl acrylate 250g vinylbenzyl chloride 50g dodecanethiol 3g Method 2 gallon funnel with croft stirrer ( Pfaudler) “first aqueous solution” in the reactor
After adding and expelling with nitrogen four times, the “first monomer liquid”
Add 100g, increase the pressure to 35psig with nitrogen, and raise the temperature to 50℃.
It was heated to. Continuous initiator flow and continuous reductant flow each hour
Started at a rate of 10g. Three hours after the addition, with stirring (235 rpm), the first monomer liquid and continuous emulsifier streams were pumped into the reactor at 40 and 110 g per hour, respectively, for 19 hours. The second monomer liquid was pumped in at a rate of 50 g/hour for 3 hours while a continuous initiator stream, a continuous reducing agent stream, and a continuous emulsifier stream were introduced in succession. Continued continuous initiator flow, continuous reducing agent flow, stirring and 50°C temperature for an additional 45 minutes. The obtained latex (C
-2) The solid content is 40.4% and the particle size is approximately 1120Å.
It was hot. Another latex was prepared as in C-2, except that the first monomer liquid was fed for 20 hours instead of 19 hours, the second monomer liquid was not added, and after the first monomer liquid feed was stopped. Continuous initiator flow, continuous reducing agent flow, stirring, and holding at 50°C were continued for 4 hours. The resulting latex (C-3) (not an example of the invention) had a solids content of 39.2% and a particle size of 1115 Å. Add enough dodecylbenzyldimethylsulfonium chloride to a portion of this latex to provide an additional 0.09 sulfonium ions per gram of polymer in the latex.
It was made into milliequivalents and the pH was adjusted to 7.6. (Latex C
-3A) A portion of the latex (C-2) was mixed with dimethyl sulfide in an amount calculated to be in excess based on the amount of active halogen in the latex while stirring.
The resulting mixture was left at room temperature for 16 hours. The latex (-A) was then steam distilled and found to have 0.05 milliequivalents of bound sulfonium ions per gram of polymer. A portion of Latex-A was diluted with water to a solid content of 10% and the pH was adjusted to 7.0. In the pump stability test, there was a small amount of coagulation and only a slight change in viscosity at the end of the test after 21 days. Control latex C-3A showed severe clotting after 9 days in a similar test. Pump test is 10
Pour 3000 ml of % solids latex into a 1 gallon container.
Model 9M143 Teel working at 3000rpm
It was pumped up using a centrifugal immersion pump. Water was added periodically to compensate for evaporation losses, ie to maintain the same volume and concentration. The latex was periodically observed for signs of instability. The test is carried out after clotting has become severe enough to stop the pump, or whether or not21
I stopped after a day. EXAMPLES Two latexes containing vinylbenzyl chloride copolymers having the same average composition but with different addition methods of vinylbenzyl chloride polymerized into the polymer particles were prepared according to the formulations shown in the table.

[Table]
The latex was made in a 2 gallon glass lined Fowler reactor with a cloft stirrer. Water, soap, a chain transfer agent, and a reaction initiator were added to the reactor, stirring was started, the lid was closed, and the air was purged with nitrogen four times. Put the monomers (except vinyl benzyl chloride in latex C-5) into a reactor and heat at 50°C.
and kept at that temperature for 20 hours. The temperature was raised to 70°C and the reaction was continued until the reactor pressure became constant. The resulting latex C-4 was cooled and taken out from the reactor. For latex C-5, vinylbenzyl chloride monomer was added at this point and stirring was continued at 70°C for 2 hours. Latex C-5 was then cooled and taken out. The analysis results of the product are shown in the table below.

Table: To each latex was added 2% dodecylbenzyldimethylsulfonium chloride, based on polymer solids, and each was diluted with water to a solids content of 20%. To half of the diluted latex C-5 was added 4 moles of nucleophyl dimethyl sulfide for each mole of polymerized vinylbenzyl chloride in the latex. The resulting reaction was continued at 30° C. for the time indicated in the table below to produce Latex-A. The other half of Latex C-5 was made into Latex-B in the same manner except that a different nucleophyl, ie, the same molar ratio of trimethylamine was used in place of dimethyl sulfide. One half of Latex C-4 was processed as was done with Latex-A to produce Comparative Latex C-4A. Latex C-
The other half of 4 was processed as was done for latex-B to produce comparative latex C-4B. Conversion of benzyl chloride groups to benzyl onium ions was confirmed by titration of chloride ions with silver nitrate solution. The results are shown in the table.

[Table] These data show that comparative latex C-4, which has a relatively uniform distribution of copolymerized vinylbenzyl chloride, converts more slowly and to a lesser extent than the structured particle latex, ie, latex C-5. I found out it was small. EXAMPLE - XI A series of latexes were prepared in the same manner as Latex C-5 with the following compositions: Percent monomer 48-X Styrene 50 Butadiene 2 2-Hydroxyethyl acrylate X Vinylbenzyl chloride Dodecylbenzyldimethylsulfonium chloride was sufficiently added to the product at 5.0 to give 2% by weight based on the polymer in the latex. Each latex was diluted with water to a solids content of 20%. A portion of each diluted latex was reacted with nucleofoil for the time indicated in the table below to produce -XI according to the method of the example. Conversion to onium ions was determined by titration of the chloride ions released in the reaction, and the product was vacuum stripped before testing. The stability of the latex products was evaluated using the friction test described above. Data are shown in the table.

Table: Samples designated as <1 solidified as soon as a finger touched a drop of latex. Samples marked as >20 did not coagulate and could be rubbed to dryness. The latex was applied to the same test side of standard American cedar wallboard. The test plates were then air-dried for 65 hours and immersed in a bath of deionized water to observe the state of the coating. For comparison with the cationic latex of the present invention,
A highly stable anionic latex containing a copolymer of styrene, butadiene, hydroxyethyl acrylate, and itaconic acid was coated and similarly tested. (Comparative Example C-8). As soon as the anionic latex (C-8) was applied, it began to be absorbed into the wood. (weak yield strength), the cationic latex-XI remained on the surface and had no tendency to be absorbed. (Good yield strength) After drying, the anionic latex formed a film with a dull appearance. Cationic latex-XI created a beautiful, shiny film that adhered to the surface of American cedar. The test results are summarized in a table.

[Front] Reddish color
All of the cationic latexes tested, with the exception of Latex, were found to have superior water resistance after air drying compared to the stable anionic latexes having styrene/butadiene copolymer groups. Example XII - 2% azobisisobutyronitrile as initiator, 1% dodecylbenzyldimethylsulfonium chloride as surfactant, and chain transfer agent per 100 parts of monomer in a batch emulsion polymerization reactor. as dodecanethiol and 2,6-di-t-butyl-
Precursor latexes were prepared using 0.1 part each of p-cresol. A reactor was charged with a reaction initiator, a surfactant, a chain transfer agent, and 233 parts of water.
2 parts of 2-hydroxyethyl acrylate and 1.33 parts of styrene were added and the air in the reactor was purged with nitrogen. A total of 30 parts of sufficient styrene was added to this, 63 parts of butadiene was added, the temperature was maintained at 50°C for 4 hours, and then raised to 70°C until the rate of pressure drop was constant, about 7°C.
It kept time. Next, 5 parts of vinylbenzyl chloride was added and the mixture was kept at 70°C for an additional 2 hours. The contents were stirred throughout the reaction. The fluid latex (C-9) obtained after opening the reactor and cooling the reaction mixture has a solids content of
At 27.7%, the particle size was 1250 Å and the pH was 3.7. This latex was shear unstable. (1 or less in friction test) Various nucleophyles shown in the table were mixed in separate parts of latex C-9 and reacted at the time and temperature shown in the table. The reaction time was selected according to the approximate time required to obtain a product that is very frictionally stable, ie, stable for more than 20 rubs. As for Example XII, the reaction temperature was changed from 25°C to 50°C. The latex obtained after the reaction was stripped under vacuum.

[Table] The pH of over-produced products is measured using an aluminum test plate (Parker
3003-H14, 4 inches x 6 inches x 0.025 inches, 10.16 cm x 15.24 cm x 0.6 cm). This treatment is shown in the table.

[Table] Two coated plates of each example were placed in an oven at 175°C, and one plate was baked for 5 minutes and the other plate was baked for 30 minutes. The burned boards were then immersed in water at 70°C for 2 hours, and the appearance before and after this treatment was recorded. The data are shown in the table.

[Table] Before XII Dark yellow Dark yellow
After that, it becomes reddish and remains unchanged.

[Table] In addition, when the burnt boards of Example XII were examined by applying a small piece of pressure-sensitive tape (Scotchi tape) to them before hot water treatment and then rapidly peeling off the tape, it was found that the coating adhered well in all cases. After water treatment, the water was blown off from the boards, air-dried for 30 minutes in the atmosphere, and a similar adhesion test was conducted, but no film was removed from any of the boards. Example - XII 0.2 parts of dodecanethiol in 300 parts of water in a batch system.
Using 2 parts of azobisisobutyronitrile and 5 parts of dodecylbenzyldimethylsulfonium chloride, 40 parts of styrene and 55 parts of butyl acrylate were heated at 50°C.
After stirring for 17 hours and 1 hour at 70°C to carry out an emulsion polymerization reaction to produce about 90% conversion monomer, 5 parts of 2-bromoethyl methacrylate was added and the reaction was continued under the same conditions for another 2 hours to form a latex. Tsukutsuta. The product fluid latex (C-
The solids content of 10) was 25.7% and the particle size was 1070 Å. The frictional stability of this latex was poor. (Rub once or less) Rub the Nucleo File shown in the table below with C-10.
It was mixed into latex in portions and left at 25°C to react until the friction stability of the latex was achieved.

[Table] Min
XII Tetramethyl 0.29 4 0.27 0.15
Thiourea
a. meg〓g polymer standard in raw material latex
b. Polymer reference example in meg〓g product latex Contains 31.1% solids with 0.16 meq total sulfonium groups per gram of polymer, of which 0.06 meq is chemically bound at or near the particle surface. Mix 126 g of latex X with a 7:1 excess of hydrogen peroxide (4.97 g of 30% solution) in a closed reactor.
Stirred at 35°C for 22 hours. Most of the sulfonium groups were oxidized to sulfoxonium groups. There was no loss of colloidal stability and the product had significantly less odor than latex. Example - 40 parts of styrene and 55 parts of butyl acrylate using 0.2 parts of dodecanethiol, 2 parts of azobisisobutyronitrile and 4 parts of dodecylbenzyldimethylsulfonium chloride in 300 parts of water at 50°C for 18 hours An emulsion polymerization reaction was carried out with stirring at 70° C. for 2 hours to obtain about 90% conversion of the monomer, and then 5 parts of 2-chloromethylbutadiene was added and the reaction was carried out for an additional 2 hours under the same conditions. The solids content of the fluid latex (C-11) which could be cooled by opening the reactor was 24.3% and the particle size was 1450 Å. This latex had poor frictional stability. (Less than 1 rub) The nucleofoil shown in the table below was mixed with portions of Latex C-11 and the mixture was left to react at 35°C until the friction stability of the product was very good. (Rub 20 times or more).

[Table] Ruamine Tetrame 0.50 4 0.535 0.398
Cirthio urea
a. meg〓g polymer standard in raw material latex
b. Meg〓g Polymer standard example in product latex Using 0.2 parts of dodecanethiol, 2 parts of azobisisobutyronitrile and 4 parts of dodecylbenzyldimethylsulfonium chloride in 300 parts of water, 50 parts of methyl methacrylate was prepared. and 45 parts of butyl acrylate were subjected to an emulsion polymerization reaction at 50°C for 16 hours and at 70°C for 3 hours with stirring to obtain about 90% conversion of the monomer, and then 5 parts of vinyl bromide was added and the polymerization was carried out under the same conditions. The reaction was then continued for another 2 hours to produce latex. The fluid latex (C-12) obtained after opening and cooling the reactor had a solids content of 238% and a particle size of 1490 Å. The friction stability of this latex was poor. (Rub 1
A portion of this latex (C-12) was mixed with 0.52 milliequivalents of tetramethylthiourea for each gram of polymer in the latex, and the mixture was left at 25°C for 7 days. The latex product was shear stable (greater than 20 rubs) with a total charge of 0.28 milliequivalents and a combined charge of 0.20 equivalents per gram of polymer in the latex. Example - Styrene using 0.1 part of dodecanethiol as chain transfer agent, 2.2'-azobisisobutyronitrile as catalyst and 1 part of dodecylbenzyldimethylsulfonium chloride (activity basis) as emulsifier.
54 parts of butadiene and 2 parts of 2-hydroxyethyl acrylate were subjected to batch emulsion polymerization reaction at 50°C for 3 hours and at 70°C for 7 hours to prepare a latex. The initial latex, which was cooled and passed through cheesecloth, had a solids content of 37.9% and was allowed to stand for 18 hours. When examined under a microscope, the latex particles were relatively uniform in size, with an average particle diameter of 1265 Å. 1980 parts of the initial latex (wet basis) was mixed with sufficient deionized water to make 4000 parts by weight of the diluted latex. Diluted latex C-13 and 2,
10 parts of 2'-azobisisobutyronitrile was placed in a reactor and air was purged with nitrogen. Reactor contents at 50℃
Heat 200 parts of styrene and 50 parts of vinylbenzyl chloride.
The mixture of parts was charged into the reactor under pressure. The mixture in the reactor was stirred at 70°C for 4 hours. The product was cooled and filtered to obtain a latex (C-14) with a solids content of 21.0%. Upon microscopic examination, the latex particle size was relatively uniform, with an average diameter of 1440 Å. Latex C
Comparing the micrographs of C-13 and C-14, there was no sign of new particle generation. Latex C-14 contained 0.042 milliequivalents of chloride ions (from emulsifier) per gram of solids. A portion of latex C-14 was mixed with 2 moles of trimethylamine for every mole of polymerized vinylbenzyl chloride in the latex and stirred at ambient temperature for 20 hours. The resulting latex () was frictionally stable and contained 0.085 milliequivalents of chloride ion per gram of solids, representing a reaction of 0.043 milliequivalents of trimethylamine per gram of solids. (0.085
-0.042) Excess trimethylamine was removed by vacuum distillation. (Using Linco Evaporator) Another portion of latex C-14 was treated in the same manner as described for latex, except that the reaction time was 4 days instead of 20 hours. This latex () is frictionally stable and contains 0.24 meq. of chloride ion per gram of solids, representing a reaction of 0.2 meq. of trimethylamine per gram of solids. (0.24-0.042) Example A latex was prepared as described in the example except that (a) the second monomer liquid was not added; (b) the first monomer liquid contained 26% styrene and chloride as monomers. 24% vinylbenzyl, and 40% butadiene and monomers
Contains 0.1 part dodecanethiol per 100 parts;
(c) The continuous initiator stream and the continuous reducing agent stream are stirred and the first
After stopping the supply of monomer liquid, the reaction was continued at 50°C for 4 hours. The resulting latex is 39.8% polymer solids.
It was hot. The latex was filtered and dialyzed against deionized water for 72 hours. The emulsifier concentration was adjusted to 0.1 milliequivalents of dodecylbenzyldimethylsulfonium chloride per gram of solids. This latex was diluted to 20% solids. (Latex C-15). 0.25 milliequivalents of dimethyl sulfide per gram of polymer solids was added to latex C-15 and the mixture was stirred at 30°C.
Samples were taken periodically and unreacted vinylbenzyl chloride was removed from the samples to stop the reaction. The sulfonium ion concentration was determined by titrating the chloride ions in the sample. The results are shown in Table XI.

[Table] Stability.
The result is 0.64 meg of bond charge per gram of polymer.
or more indicates that the particles substantially swell. Highly charged latexes do not have very high viscosities and often do not gel, forming a viscosity of about 35
It is not possible to achieve a solid concentration of more than %. 0.1 per gram
Latexes with bonded charges between 0.32 meg and 0.32 meg are very stable and have low viscosities. These have substantial amounts (1.25-1.47 meg/g) of uncovered benzyl chloride groups. These latexes, when molded and dried, form hydrophobic films cross-linked with butadiene double bonds by oxidative curing. The chloromethyl groups in the resulting cross-linked film are then used in a quaternization reaction to create an ionic membrane.

Claims (1)

[Scope of Claims] 1. A method for producing a cationic latex characterized by comprising the following steps (a), (b) and (c): (a) nonionic organic polymer; (b) a nonionic ethylenically unsaturated monomer with activated halogen and a nonionic ethylenically unsaturated monomer without activated halogen; above with a thin capsule layer of water-insoluble organic copolymer
producing a latex comprising copolymer particles in which the nonionic organic polymer core of (a) is encapsulated and activated halogen is uniformly or randomly distributed throughout the particles; in an amount of 0.01 to 0.5 milliequivalents per gram of latex particles made up of and 0.4 to 0.4 milliequivalents per gram of copolymer in the capsule layer.
and (c) the latex prepared in (b) above is heated between 0°C and 80°C.
Consists of polymer particles with pH-independent cationic groups chemically bonded to the particle surface by reacting with a low molecular weight, water-stable, non-ionic nucleophyl group that can diffuse into an aqueous medium at a temperature of Manufacture latex. 2. The reaction is carried out until PH-independent cationic groups are present in an amount of 0.01 to 0.5 milliequivalents per gram of latex particles and 0.4 to 1.6 milliequivalents per gram of copolymer in the capsule layer. A method according to claim 1. 3. The method according to claim 1 or 2, wherein the amount of activated halogen is between 0.01 and 1.4 milliequivalents per gram of particles. 4. The latex of the copolymer particle with an activated halogen bound to the capsule layer at or near the particle surface also includes an activated halogen bound throughout the particle.
3. The method according to paragraph 2, paragraph 3. 5 The activated halogen is vinyl chloride-benzyl, 2-chloromethylbutadiene, vinyl bromide,
5. A method according to any one of claims 1 to 4, provided by a copolymerized monomer selected from the group consisting of bromoalkyl acrylate and bromoalkyl methacrylate. 6 Nucleophyl is tetraalkylthiourea or has the formula R ₁ -S-R ₂ (wherein R ₁ and R ₂ individually represent lower alkyl, hydroxyl lower alkyl, or R ₁ and R ₂ have 3 to 5 carbon atoms); The compound is a compound represented by (bonded as one alkylene group), and the cationic group chemically bonded thereby is a sulfonium group. The method described in Section 1. 7. The method according to claim 6, comprising the step of oxidizing at least a portion of the sulfonium groups to sulfooxonium groups. 8 The water-insoluble organic copolymer constituting the capsule layer in step (b) contains a nonionic ethylenically unsaturated monomer with an activated halogen and a nonionic ethylenically unsaturated monomer without an activated halogen. unsaturated monomers and a small stabilizing amount of (i) a free radical catalyst and (ii) a mixture of cationic and nonionic surfactants (the amount of the surfactant mixture is the amount of additional monomers). In the presence of a preformed latex containing less than or equal to the amount necessary to generate new particles in the presence of
Claims 1 to 7 are produced by copolymerization at a temperature of ℃ to 80℃.
The method described in any one of paragraphs. 9 The preformed latex was produced in situ by emulsion polymerization of nonionic ethylenically unsaturated monomers to 85-95% conversion, and the unpolymerized monomers were The method according to claim 8, which forms a nonionic monomer for the subsequent copolymerization reaction. 10. The method of claim 8, wherein the preformed latex is a previously formed latex substantially free of residual unpolymerized monomer. 11. The method of claim 8, wherein a stabilizing amount of a cationic surfactant or a nonionic surfactant or a mixture thereof is added after the copolymerization step. 12. The method according to any one of claims 8 to 11, wherein the temperature is maintained at 50°C to 70°C. 13. The method of claim 8, wherein the activated halogen-free nonionic monomer and the activated halogen-bearing monomer are added to the preformed latex as a mixture. 14 Water-insolubility of nonionic ethylenically unsaturated monomers with a nonionic organic polymer core and activated halogens and nonionic ethylenically unsaturated monomers without activated halogens an amount of 0.01 to 0.5 milliequivalents per gram of latex particles consisting of a thin capsule layer of an organic copolymer and constituted by the activated halogen and 0.4 to 2.5 milliequivalents per gram of copolymer in the capsule layer. an aqueous colloidal dispersion of cationic structured latex particles derived from polymer particles present in an amount of . 15. Claim 14, wherein the amount of cationic groups is between 0.04 and 0.35 milliequivalents per gram of the particles made up and less than 1.6 milliequivalents per gram of copolymer in the capsule layer. Aqueous colloidal dispersions as described. 16 The cationic group is mainly a sulfonium group,
The aqueous colloidal dispersion according to claim 14 or 15, wherein the aqueous colloidal dispersion is an isothiouronium group or a quaternary ammonium group, and the quaternary ammonium group is a pyridinium group. 17. The aqueous colloidal dispersion according to claim 14 or 15, wherein at least some of the cationic groups are sulfoxonium groups. 18. Colloidal stability is achieved primarily by cationic groups chemically bonded to the copolymer at or near the particle surface, claim 1.
The aqueous colloidal dispersion according to any one of items 4 to 17. 19. The aqueous colloidal dispersion according to any one of claims 14 to 18, wherein the organic polymer core is an emulsion polymer of a nonionic ethylenically unsaturated monomer. 20. The aqueous colloidal dispersion according to claim 19, wherein the organic polymer core is a polymer of ethylenically unsaturated hydrocarbon monomers. 21. The aqueous colloidal dispersion according to claim 14, wherein the organic polymer core is a polymer of a nonionic derivative of an ethylenically unsaturated carboxylic acid. 22. The aqueous colloidal dispersion according to claim 14, wherein the organic polymer core is a copolymer of styrene or butadiene. 23. The aqueous colloidal dispersion according to claim 14, wherein the organic polymer core is a polymer of acrylic ester or methacrylic ester. 24. The aqueous colloidal dispersion according to claim 14, wherein the activated halogen monomer is vinylbenzyl chloride. 25 The water-insoluble copolymer capsule layer is approximately 100%
15. Aqueous colloidal dispersion according to claim 14, having a thickness not exceeding Å.