NO172122B - LATEX MATERIAL, ITS MANUFACTURING AND USE - Google Patents

Description

This invention relates to polymer materials comprising phosphinyl-containing, ethylenically unsaturated compounds, as well as the manufacture and use of the materials, see respectively claims 1, 5

and 7.

The aforementioned phosphinyl-containing, ethylenically unsaturated compounds are useful in the production of polymeric materials when they are homopolymerized or copolymerized with compounds containing polymerizable 1,2-ethylenically unsaturated portions. The polymer materials produced are useful in latex paints, in plastic-metal laminates, coatings for metals and in adhesives. Polymeric materials prepared from compounds containing 1,2-ethylenically unsaturated moieties are often brought into contact with or applied to metals in various ways.

A main problem is finding a polymer material that has good adhesion to particular metals. What is needed is a polymer material prepared from compounds containing 1,2-ethylenically unsaturated moieties which have good adhesion properties to metals and other substrates.

In one aspect, the invention is a latex material containing a new phosphinyl-containing, ethylenically unsaturated compound selected from a (hydroxy)phosphinylalkyl acrylate or methacrylate and a (dihydroxy)phosphinylalkyl acrylate, methacrylate or ethacrylate, and also the corresponding ammonium, alkali metal- or alkaline earth metal salts thereof, in amounts as set forth in claim 1. These compounds are hereinafter referred to as "HP acrylic monomer" or "DHP acrylic monomer".

Such a polymer can be obtained by polymerization of:

(a) an HP or DHP acrylic monomer and

(b) at least one copolymerizable 1,2-ethylenically unsaturated monomer.

In another aspect, this invention is a method for producing a latex material as stated in claim 5.

The polymer materials produced from the aforementioned 1,2-ethylenically unsaturated (hydroxy)-phosphinyl- and (dihydroxy)phosphinyl-containing compounds have surprisingly good adhesion to many metals. The polymer materials also have improved anti-corrosive properties.

Preferred HP acrylic monomers included in materials according to this invention are as indicated by the following formula:

where:

R"*" is hydrogen or methyl;

R 2 is individually in each occurrence hydrogen or C^_^g-alkyl;

M is an alkali metal, alkaline earth metal or ammonium; and

a is 1 or 2.

In the embodiments where M is an ammonium portion or an alkali metal, a is equal to 1. In the embodiments where M is an alkaline earth metal, a is equal to 2.

In the formula above, R 2 is preferably hydrogen or C 1 -alkyl, more preferably hydrogen. R 1 is most preferably methyl.

M is preferably an ammonium portion or an alkali metal. M is more preferably an ammonium portion, potassium or sodium. A is preferably 1.

The (hydroxy)phosphinylalkyl acrylates and (hydroxy)phosphinylalkyl methacrylates can be prepared by reacting hypophosphoric acid with a suitable aldehyde or ketone to produce a <x-hydroxyalkylphosphoric acid, which is then reacted with acrylic or methacrylic acid to produce the new connections. The reaction sequence can be exemplified by equations III and IV.

1 2

where R and R are as defined above.

In the first step of this process, the hypophosphorous acid is brought into contact with a suitable aldehyde or ketone in a ratio of between 3:1 and 1:1. In this reaction there can be no excess of aldehyde or ketone since such an excess would result in multiple additions of aldehyde or ketone to the acid. This procedure is carried out in an aqueous solution. It is preferred to add the aldehyde or ketone to an aqueous solution of the hypophosphorous acid, since this reaction is exothermic and a slow addition will result in much better regulation of the reaction temperature.

Generally, this step can be carried out at any temperature at which the reaction takes place. Preferred temperatures are between 20 and 100°C, with temperatures between 70 and 90°C being most preferred.

This method can be carried out at any pressure at which the reaction takes place. Atmospheric, subatmospheric and superatmospheric pressure can be used. Atmospheric pressure is preferred. Although not necessary, it is preferred to carry out this reaction under an atmosphere of inert gas. Examples of inert gases include nitrogen and argon.

Any reaction time that produces the desired conversion is suitable. Generally, reaction times of between 3 and 10 hours are preferred. After completion of the reaction, the water-solvent is stripped off.

The hydroxyalkyl phosphoric acid produced by the reaction described above is then contacted with methacrylic acid or acrylic acid at a ratio of between 3:1 to 1:3, with a ratio of between 2:1 and 1:2 being preferred and a ratio of 1: 1 as most preferred. When there is an excess of a reagent, it is preferred that this reagent is methacrylic or acrylic acid. This process is usually carried out in an inert organic solvent. Examples of preferred inert organic solvents are aromatic hydrocarbons and chlorinated solvents. Among more preferred solvents are perchlorethylene and xylene. It is preferred that the solvent used has a boiling point of over 100°C, and most preferably that the solvent has a boiling point of over 120°C.

This reaction is carried out in the presence of an esterification catalyst. Preferred esterification catalysts are strong acids. More preferred strong acids include sulfonic, sulfuric and phosphoric acids. A most preferred catalyst is p-toluenesulfonic acid.

Any temperature at which the turnover takes place

is suitable. This reaction is preferably carried out at the reflux temperature of the solvent. It is more preferred that the reflux temperature is above 100°C, with a reflux temperature of above 120°C being most preferred.

During the course of this process, water is formed as a by-product. It is preferred to remove the water when it is formed, since the process is an equilibrium process and removal of water drives the reaction to completion.

This turnover can be carried out at atmospheric and superatmospheric pressure. Atmospheric pressure is preferred. An inert atmosphere can be used.

Turnover times that provide the desired conversion are suitable. Preferred trading times are between 4 and 10 hours.

Preferred DHP acrylic monomers used in the invention are those corresponding to the formula:

or where R<1> is hydrogen, methyl or ethyl, R<2> is independently selected from hydrogen and alkyl of 1-10 carbon atoms, and M+ is an ammonium cation, an alkali metal cation or 1/2 of an alkaline earth cation. It should be understood that the ammonium cation can be designated as NH^ , the alkali metal cations as Li<+>, Na<+>, K<+>, Rb<+> and Cs<+> and that "1/2 of an alkaline earth metal cation" will correspond to 1 /2 Mg<++>, 1/2 Ca<++>, 1/2 Ba<++> or 1/2 Sr<++>. A typical alkaline earth, the calcium salt, can therefore be specified with the structure:

Preferred monomers according to the preceding formulas are

1 2

those where R is hydrogen or metal and R is chosen independently from hydrogen and alkyl with 1-3 carbon atoms. It is most preferred that the DHP acrylic monomer is (dihydroxy)phosphinylmethyl methacrylate, i.e. a compound where R is

2

methyl and R is hydrogen.

Preferred salts are those where M<+> is an ammonium cation, a sodium cation or a potassium cation.

The DHP acrylic monomers can be prepared by reacting between

a dialkylphosphonoalkyl acrylic ester and a trialkylhalosilane to form a bis(trialkylsilyl)ester intermediate, which is saponified to a corresponding salt and can be acidified to form a DHP acrylic monomer in the form of a free acid.

Dialkylphosphonoalkyl acrylic esters are known compounds and

is revealed by 0'Brian et al. in U.S. Patents 2,934,555 and 3,030,347.

Dialkylphosphonoalkyl acrylic esters are formed by adding a dialkyl hydrogen phosphite to an aldehyde or ketone to form a dialkyl-1-hydroxyalkylphosphonate intermediate, which is converted to an acrylic ester by reaction with an acrylic halide in the presence of a hydrogen chloride acceptor.

The turnovers can be expressed with the equations:

where "alk" is lower alkyl, X is chlorine, bromine or iodine, and "base" is a hydrogen halide acceptor.

Because formaldehyde and lower aldehydes are more reactive with the dialkyl hydrogen phosphites than higher aldehydes or ketones, it is preferred to use the lower links in the compound series for use as intermediates.

Further conversion of a dialkylphosphonoalkyl acrylic ester to DHP acrylic monomer can, when it comes to the use of chlorotrimethylsilane, be indicated by the equations:

where Me is methyl/alk, M and X are as above or HX is equivalent

a strong acid different from hydrohalic acid.

Transesterification of the dialkylphosphonoalkyl acrylic ester with trialkylhalosilane is carried out in an aprotic solvent,

for example acrylonitrile, benzene, toluene, dimethylformamide, dimethylsulfoxide or the like. Use of acrylonitrile is preferred.

At least 2 moles of trialkylhalosilane are used for each mole of dialkylphosphonoalkyl acrylic ester. It is preferred to use 2 mol of a halotrimethylsilane. Although it is possible to use iodotrimethylsilane in this reaction, it has been found in accordance with the invention that the transesterification can easily be carried out using chlorotrimethylsilane if a stoichiometric amount of an iodide donor is present in the reaction mixture. It is therefore preferred to use a reaction mixture containing 2 mol of chlorotrimethylsilane and 2 mol of an alkali metal iodide, preferably sodium iodide or potassium iodide.

The reaction can be carried out at any temperature at which the reaction will take place. However, the turnover takes place within a reasonable time at room temperature. Consequently, reaction temperatures of from 15 to 50°C are preferred.

The turnover can be carried out at any pressure. However, the conversion takes place easily under ambient conditions so that it is not necessary to use pressure or vacuum equipment. The conversion is therefore preferably carried out at atmospheric pressure.

Due to the hydrolytic instability of trialkylhalosilanes, it is preferred to carry out the reaction under substantially anhydrous conditions. Use of drying agents, e.g. calcium chloride or Drierite tubes, are preferred. It is further preferred to carry out the reaction under a dry, inert atmosphere, for example under dry nitrogen or dry argon.

At the end of the reaction, the mixture is hydrolysed by adding at least 2 mol of water per moles of bis(trialkylsilyl) phosphonoalkyl acrylic ester. The mixture is stirred to allow separation of a slightly soluble salt, which is removed by filtration. The intermediate is subjected to hydrolysis with a base,

which cleaves the trialkylsilyl groups and forms a corresponding metal salt. This conversion takes place easily at room temperature and

- pressure, so that elevated temperatures are not necessary

and press. The salt can be used directly in the production of the polymer materials according to this invention. The (dihydroxy)phosphinylalkyl acrylic compound can be polymerized in the form of the salt, and if desired, the resulting polymer can be acidified to convert the salt to the corresponding acid form.

The resulting monomer salt can be converted to the free acid by treatment with a stoichiometric amount of a mineral acid,

such as hydrochloric, hydrobromic, hydroiodic, sulfuric or phosphoric acid.

The polymer materials according to this invention include the product obtained by vinylic polymerization of an HP-

or DHP acrylic monomer. The polymer materials according to this invention include homopolymers of HP or DHP acrylic monomers and also copolymers with at least one other compound containing a polymerizable 1,2-ethylenic unsaturated portion.

The polymer materials preferably comprise the reaction product of (a) between 0.5 and 99% by weight of an HP or DHP acrylic monomer, and (b) between 99.5 and 1% by weight of at least one copolymerizable

1,2-ethylenic unsaturated compound.

The copolymerizable materials according to this invention more preferably contain between 1 and 10% by weight of the new HP or DHP acrylic monomers according to this invention, and most preferably between 1 and 5% by weight of HP or DHP acrylic -the monomer.

The novel compounds of this invention are generally clear, viscous liquids which are soluble in water and polar organic solvents such as methanol, ethanol and dimethyl sulfoxide.

The salts of the (hydroxy)phosphinylalkyl acrylate, the (hydroxy)phosphinylalkyl methacrylate, the (dihydroxy)phosphinylalkyl acrylate,

The -methacrylate or -ethacrylate is prepared by bringing the (hydroxy)phosphinylalkyl acrylate, the (hydroxy)phosphinylalkyl methacrylate, into contact with a base containing an alkali metal, alkaline earth metal or an ammonium portion in water under such conditions that the salts are formed. Conditions for such transactions are well known to professionals in the field. Examples of preferred bases include ammonium hydroxides, alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides and alkaline earth metal

carbonates.

Alkali metal here refers to lithium, sodium, potassium, rubidium and cesium. Preferred alkali metals are lithium, potassium and sodium, with potassium and sodium being most preferred. Alkaline earth metals here refer to beryllium, magnesium, calcium, strontium and barium. Preferred alkaline earth metals are magnesium and calcium.

Any compound containing a polymerizable 1,2-ethylenic unsaturated moiety is useful in this invention. Examples of such compounds include monovinyl aromatic compounds, such as styrene, p-vinyltoluene, p-chlorostyrene; fi - ethylenically unsaturated acids, such as acrylic acid and methacrylic acid; alkyl esters of "K^</>S -ethylenically unsaturated monocarboxylic acids containing from 1 to 18 carbon atoms in the alkyl group, such as methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate and methyl methacrylate; /3-ethylenically unsaturated nitriles, such as acrylonitrile and methacrylonitrile; /3-ethylenically unsaturated amides, such as acrylamide and meth-acrylamide; vinyl esters, such as vinyl acetate and vinyl propionate; vinyl halides, such as vinyl chloride and vinyl bromide; vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; vinyl ketones, such as vinyl methyl ketone and vinyl ethyl ketone; vinylidene halides, such as vinylidene chloride and vinylidene bromide; hydroxyalkyl esters of acrylic and methacrylic acids, such as hydroxypropyl acrylate, hydroxyethyl acrylate and hydroxybutyl acrylate; nitriles of ethylenically unsaturated carboxylic acids such as acrylonitrile and methacrylonitrile; ethylenically unsaturated carboxylic acids such as acrylic acid; ethylenically unsaturated alcohols such as allyl alcohol and aromatic compounds substituted with 1,2-ethylenically unsaturated moieties such as styrene, vinyltoluene and tert-butylstyrene.

The polymer materials according to this invention are produced by methods that are well known in the field, and such productions are not the point of the invention. Suitable polymerization techniques include solution polymerization, dispersion polymerization, emulsion polymerization, bulk polymerization, and heterogeneous polymerization. These polymerizations can be carried out continuously or in batches as appropriate.

In one embodiment, the polymer materials according to this invention can be produced by free-radical-initiated solution polymerization. In particular, the phosphinyl-substituted 1,2-ethylenically unsaturated monomers are homopolymerized, or copolymerized with one or more compounds containing a polymerizable 1,2-ethylenically unsaturated moiety, in an organic solvent medium in the presence of a free radical-type catalyst under an oxygen -free atmosphere. The monomer components are mixed and polymerized in the proportions indicated above.

Examples of solvents include the lower alcohols such as ethanol, propanol and butanol; aromatic hydrocarbons such as toluene, benzene and xylene, halogenated hydrocarbons such as methylene chloride and tetrachloroethane and others such as butyl acetate and butoxyethyl acetate.

Representative catalysts used in free radical catalyzed polymerization include azo and peroxide types, e.g. peroxides such as benzoyl peroxide; hydroperoxides such as t-butyl hydroperoxides; peracids such as perbenzoic acid; peresters, such as t-butyl peroctoate; and azo compounds such as azobisiso-butyronitrile. Free radical-catalyzed polymerization is readily carried out at temperatures from room temperature (20°C) to 200°C under atmospheric to superatmospheric pressure at catalyst concentrations of 0, in the case of thermal initiation, to 5% by weight, based on the weight of monomers, preferably from 0.01 to 5% by weight of catalyst in pure form or in an inert solvent for the catalyst. Thermal initiation usually takes place at temperatures between 60 and 120°C.

It may often be necessary to use a chain regulator to provide a molecular weight in the desired range. Examples of chain regulators that can be used include long-chain alkyl mercaptans, e.g. t-dodecyl mercaptan with the formula: H3CC(CH3)2CH2C(CH3)2CH2C(CH3)2SH, (XIII)

short-chain alkyl mercaptans such as butyl mercaptan and 2-hydroxy-ethyl mercaptan, isopropanol, isobutanol. Long-chain alcohols, e.g. lauryl alcohol, octyl alcohol, cumene, carbon tetrachloride, tetrachloroethylene and trichlorobromomethane. The amount of chain regulator that can be used depends on the particular system and the conditions and can vary from 0 to 5% by weight, based on the monomer weight. Illustrative is that the use of from 0 to 1% by weight of t-dodecyl-

mercaptan serves to provide as wide a molecular weight range in aqueous media as is desirable.

In another embodiment, the polymer materials according to this invention can be produced by ionic polymerization techniques.

Representative ionic catalysts include lithium-based catalysts, e.g. metallic lithium, alkyl lithium and other lithium compounds, and Ziegler catalysts, e.g. reducible halide of titanium or vanadium in combination with aluminum trialkyl or diethyl aluminum chloride, or lithium aluminum hydride. Ionic polymerization is advantageously carried out in an inert hydrocarbon solvent such as lower alkane or lower aromatic hydrocarbon at temperatures in the range of -20 to 140°C under pressures varying from atmospheric to superatmospheric and in the presence of from 1 to 200 ppm of ionic catalyst, based on the weight of monomers. Polymerization can be similarly carried out with cationic catalysts at temperatures of

from -100 to 100°C. Such catalysts include the etherates of boron trifluoride and aluminum trichloride and Ziegler catalysts such as a reaction product of reducible transition metal compounds such as titanium tetrachloride or trichloride and reducing organometallic compounds such as triethylaluminum or diethylaluminum chloride.

In another embodiment, low-pressure polymerization techniques can be used whereby the compounds containing the polymerizable 1,2-ethylenically unsaturated portions are K-olefins.

Low pressure polymerization of β-olefins with catalyst systems composed of a partially reduced heavy transition metal component and an organometallic reducing component to form high molecular weight, solid, relatively linear, high density polymers is well known. Such polymerizations are characteristically carried out in an inert organic liquid diluent under an inert atmosphere and at relatively low temperatures, e.g. 0 to 100°C and low pressures, e.g. 0 to 7.0 kg/cm gauge pressure. Typical transition metal components are the halides, oxyhalides and alkoxides of metals selected from groups IVB, VB, VIB and VIII

in the Periodic Table of the Elements as given in "Handbook of Chemistry and Physics", 48th ed., Chemical Rubber Company. Common organometallic components include the metal alkyls, the metal alkyl halides and dihalides, the metal hydrides and the like

components in which the metals are selected from groups IA, IIA and HIA in the periodic table of the elements. The o(-olefin polymers formed by low pressure polymerization usually have molecular weights in the range of 100,000 to 300,000 or even as high as 3,000,000.

In yet another embodiment, the polymer materials according to this invention can be produced by emulsion polymerization whereby the monomers are dispersed in an aqueous medium containing a free radical type catalyst and a stabilizing emulsifier or a mixture of emulsifiers. Suitable free radical catalysts include the persulfates (including ammonium, sodium, and potassium persulfates), hydrogen peroxide, the perborates, and the percarbonates. Organic peroxides can also be used either alone or in addition to an inorganic peroxygen compound. Typical organic peroxides include benzoyl peroxide, tert-butyl hydroperoxide, cumene peroxide, acetyl peroxide, caproyl peroxide, tert-butyl perbenzoate, tert-butyl diperphthalate and methyl ethyl ketone peroxide. The amount of catalyst usually required is roughly from 0.01 to 3.0% by weight, based on the monomer mixture. In order to increase the rate of polymerization, improve the polymer properties and reduce unwanted side reactions, it is often desirable to activate the catalyst. Activation of the catalyst also has the effect of lowering the temperature required to polymerize the monomers. The activation can best be carried out using a redox system in which a reducing agent is present within the limits of 0.001 to 6.0% by weight, based on the monomers, in addition to the peroxide catalyst. Many examples of such redox systems are known. Such agents as hydrazine or a soluble oxidizable sulfoxy compound, including the alkali metal salts of hydrosulfites, sulfoxylates, thiosulfates, sulfites and bisulfites, can be used. Redox systems can be activated by the presence of a small amount (a few parts per million) of polyvalent metal ions. Ferrous ions are commonly and effectively used, or a tertiary amine which is soluble in the reaction medium can also be used as an activator.

Stabilizing emulsifiers suitable for the purposes of this invention include the anionic and nonionic surfactants. Examples of suitable anionic surfactants include the alkyl aryl sulfonates, the alkali metal alkyl sulfates, the sulfonated alkyl esters, and the fatty acid soaps. Specific examples of these well-known emulsifiers are sodium butyl naphthalene sulfonate, sodium lauryl sulfate, disodium dodecyl diphenyl ether disulfonate, N-octadecyl disodium sulfosuccinamate, dihexyl sodium sulfosuccinate and dioctyl sodium sulfosuccinate. A preferred anionic surfactant is disodium dodecyl diphenyl ether disulfonate.

Suitable nonionic surfactants include the polyethenoxy agents, e.g. ethylene glycol polyethers and ethylene nonylphenol polyethers and the like; and fatty acid esters of polyhydric alcohols, e.g. propylene glycol fatty acid ester. Other suitable nonionic emulsifiers are described in Becher, Emulsions: Theory and Practice, 2nd ed. Reinhold Publishing Corporation,

New York, 221-225 (1965). A preferred non-ionic emulsifier is ethylene nonylphenol polyether which has 40 mol of ethylene oxide per moles of nonylphenol.

The amounts of surfactants required depend primarily on the concentrations of monomers to be treated and, to a further extent, on the choice of type of surfactants, monomers and proportions of monomers. Generally, the amount of emulsifier required falls between

0.5 and 10% by weight of the monomer mixture. A preferred emulsifier system for producing the latexes according to this invention is a mixture of from 0.1 to 0.5 part of an anionic surfactant and from 4 parts to 5 parts of a non-ionic surfactant per 100 parts of monomer used in the production of the latex. Latices which do not have a measurable amount of coagulant are easily obtained when the amounts are from 0.2 to 0.3

part of anionic surfactant and from 4.0 to 4.2 parts of non-ionic surfactant per 100 parts monomer.

Polymerization of the monomers is conveniently carried out at a temperature between room temperature and 100°C, preferably between 65 and 80°C. As previously mentioned, the required temperature for the polymerization is reduced by using catalyst activators. During the polymerization, the temperature can be partly regulated by the rate at which the monomers are added and polymerized and/or by applied cooling.

As is known in the art, emulsion polymerization can be carried out batchwise or continuously. It is possible to work completely in batches, emulsify the entire monomer batch and continue with polymerisation. However, it is usually advantageous to start with part of the monomers to be used, and add the rest of the monomer or monomers as the polymerization progresses. An advantage of gradual monomer addition is that a high solids content is achieved with optimal regulation and with maximum uniformity for the product.

In yet another embodiment, heterogeneous polymerization techniques can be used to prepare the polymer materials according to this invention. Heterogeneous catalysts are readily obtained by mixing an alkyl aluminum with a reducible compound of a metal from groups IVA, VA, VIA and VIII

in the periodic table. Examples of alkyl aluminum compounds that can be used include trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-pentylaluminum, diethylaluminum chloride and diethylaluminum hydride. Metals from the groups listed above include titanium, zirconium, hafnium, thorium, uranium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten and iron. Examples of suitable reducible compounds of these metals include halides, e.g. chlorides and bromides; oxyhalides, e.g. oxychlorides; complex halides, e.g. complex fluorides; freshly precipitated oxides or hydroxides; and organic compounds, e.g. alcoholates, acetates, benzoates or acetylacetonates. Titanium compounds are preferred, for example titanium tetrachloride, titanium oxychloride or titanium acetylacetonate. A particularly preferred heterogeneous catalyst is a mixture of triisobutylaluminum and titanium tetrachloride. Such catalyst systems are prepared by dissolving each of the catalyst components in an inert liquid vehicle such as hexane under an oxygen- and moisture-free atmosphere, e.g. of nitrogen, argon, helium and the like. Current methods for producing these catalyst systems are described in more detail in U.S. Patent No. 3,113,115

and 3,257,332, by Karl Ziegler et al.

The heterogeneous catalyst process is carried out in the absence of molecular oxygen, carbon monoxide, carbon dioxide and water in a conventional reaction vessel which allows the monomers to bubble through the inert vehicle • containing the catalyst. The polymerization is carried out at temperatures in the range between 30 and 100°C and preferably between 85 and 95°C.

In order to facilitate the treatment of the gaseous "(-olefins), the polymerization zone is kept under a pressure between atmospheric pressure and 790 kPa manometer pressure in the first stage, preferably at a pressure in the range between 380 and 450 kPa manometer pressure. In a preferred embodiment, the first stage is carried out in the presence of a molecular weight regulator during the polymerization, such as hydrogen, acetylene and other commonly used chain transfer agents. If hydrogen is used as a molecular weight regulator, the amount of hydrogen used is in the range from 1 to 90 mol%, based on the monomer feed, and preferably from 25 to 50 mol%. It is further preferred that the molecular weight control agent is not present during the polymerization in the second step. The polymerization process can be carried out in a batch or continuous manner.

After completion of polymerization, any excess monomer is vented. The mixture is then treated by any conventional method to deactivate the catalyst and remove the catalyst residues and recover the polymer mixture. In one method, the deactivation of the catalyst is carried out by washing the slurry mixture with an alcohol such as methanol, n-propanol and isopropanol. The polymer is then separated from the diluent, e.g. by decantation, filtration or other similar method, after which the polymer is dried.

In yet another embodiment, the polymer material according to this invention can be produced by mass polymerization whereby the monomer components are directly brought into contact with a catalyst. In mass polymerizations, free radical catalysts can be used. Such free radical catalysts are described above. Concentrations of polymerization catalysts are usually between 0.001 and 5% by weight. The temperatures are between room temperature (20°C) and 200°C. Atmospheric pressure and superatmospheric pressure can be used. Due to the problems with heat dissipation in exothermic mass polymerizations, mass polymerization can either be terminated at relatively low conversions of between 40 and 60% by weight and excess monomer distilled off, or the polymerization can be carried out in two stages. In the first step, a large batch of monomer is polymerized to an intermediate conversion and then, to facilitate heat dissipation, the polymerization is completed in thin layers. The reaction can be carried out to completion while the monomer-polymer mixture flows either through a small diameter tube or down the walls of a column or by free fall in thin streams.

In yet another embodiment, the polymer materials according to this invention can be produced by suspension polymerization techniques. In suspension polymerization, the catalyst is dissolved in the monomer, the monomer is dispersed in water and a dispersant is incorporated to stabilize the resulting suspension. Suspending agents are usually water-soluble organic polymers, such as poly(vinyl alcohol), poly(acrylic acid), methyl cellulose, gelatin and various pectins; and water-insoluble inorganic compounds such as kaolin, magnesium silicates, aluminum hydroxide and various phosphates. Free radical catalysts described above are useful in these suspension polymerizations. Generally, catalyst concentrations of between 0.001 and 5% by weight, based on the monomer, are used. Temperatures between room temperature (20°C) and 200°C are suitable.

The polymers produced are in the form of finely granulated beads

which is easily recovered by filtration and drying.

The choice of the particular polymer isation process to be used depends on the particular monomer system used and the desired properties of the polymer material. Professionals in the field may well make such choices.

The polymer materials according to this invention have increased adhesion to metals and have anti-corrosive properties^

These polymeric materials are useful in latex paints, coatings for metals, plastic-metal laminates and adhesives.

The following examples are given to illustrate the invention. All parts and percentages are based on weight unless otherwise stated.

Example 1

A - Production of hydroxymethyl phosphoric acid

In a 500 ml 3-necked flask equipped with a magnetic stirrer, thermometer, nitrogen inlet and cooler, 264 g of 50% hypophosphorous acid was placed. The solution was heated to 80°C with stirring. Paraformaldehyde (66 g) was then added in portions (portions of

2 1/2 g) over a period of 30 minutes. After the addition was complete, the solution was kept at 80°C for 3 hours. A further 4 g of paraformaldehyde was added, and heating was continued for a further 3 hours. The clear solution was then stripped of water on a rotary evaporator, 100 ml of absolute ethanol was added, and then it was stripped again. This gave a clear liquid which became

13 31

characterized by C and p nuclear magnetic resonance.

B - Production of (hydroxy)phosphinylmethyl methacrylate

A 2-liter 3-necked flask equipped with a mechanical stirrer, nitrogen sparger, and a modified Dean-Stark trap and condenser was charged with the following reactants:

96.0 grams (1 mole) of hydroxymethylphosphoric acid

258 grams (3 moles) of methacrylic acid

0.4 grams of phenothiazine

0.8 gram of benzyltrimethylammonium chloride

0.4 gram of p-toluenesulfonic acid

1 liter perchlorethylene

While stirring and maintaining a nitrogen purge, the mixture was heated to reflux for 7 hours, during which time 17.8 mL of water was collected.

The two-phase mixture was then cooled and extracted three times with 600 ml of water. The combined water extracts were stripped on a rotary evaporator. Final removal of water and excess methacrylic acid was carried out by vacuum distillation.

The product, a clear, viscous liquid, was characterized at C 31

and on no.

Example 2 - Copolymer preparation

A polymer containing the following monomers was produced:

based on weight 53% 45% 2%

In a 1-liter flask with a round bottom equipped with a mechanical stirrer was placed:

79.5 g of methyl methacrylate

67.5 g of butyl acrylate

3.0 g of hydroxyphosphinylmethyl methacrylate

0.75 g of benzoyl peroxide

700 ml methyl ethyl ketone

The solution was refluxed for 3 hours. Methyl ethyl ketone (300 mL) was distilled off, leaving a clear, highly viscous solution.

Example 3 - Preparation of (dihydroxy)phosphinylmethyl methacrylate

One liter of acetonitrile, 236 g (1 mol) of diethylphosphonomethyl methacrylate, (CH3CH20) <p>(=0)-CH20C0C(CH3 )=CH2, and 300 g (2 mol) sodium iodide. The mixture

was stirred for 2 hours at room temperature. To the stirred mixture was added drop by drop through the addition funnel 217 g (2 mol) of trimethylchlorosilane over a period of 1 hour.

Stirring was continued at room temperature for 2 hours after the addition was complete. Water (36.0 g, 2 mol) was added dropwise to the resulting mixture, which was stirred overnight at room temperature.

The precipitated salt was removed by filtration and washed with

200 ml of acetonitrile. To the filtrate was added 800 ml of absolute ethanol and then 80.0 g (2 mol) of sodium hydroxide in portions of 5 g each. The mixture was stirred for 4 hours. The resulting precipitate of the disodium salt of the (dihydroxy)-phosphinylmethyl methacrylate, Na 2 O 2 P(=0)CH 2 O CC(CH 3 )=CH 2 , was removed by filtration, washed

with absolute ethanol and dried under vacuum. The yield was 184 g (82%).

The disodium salt, dissolved in water, was converted to acid by the addition of concentrated hydrochloric acid to a pH below 1. The resulting solution was diluted with an equal volume of absolute ethanol and concentrated using a rotary evaporator heated at 40°C. Ethanol was added periodically during the process to replace the ethanol/water azeotrope that was removed. After all the water had been removed, the precipitated sodium chloride was recovered by filtration and washed with ethanol. The filtrate and washings were concentrated to give a viscous pale yellow liquid, which rapidly darkened yellow-brown on exposure to light.

The product was characterized by nuclear magnetic resonance analysis as follows:

Example 4

Copolymerization of (dihydroxy)phosphinylmethyl methacrylate with acrylic acid

30 g of toluene was added to a 160 ml flask with a round bottom,

9.5 g of acrylic acid, 0.5 g of (dihydroxy)phosphinylmethyl methacrylate and 0.1 g of benzoyl peroxide. The solution was heated under a nitrogen atmosphere with magnetic stirring. At approximately 95°C an exothermic reaction began and a white polymer began to precipitate. The mixture was held at approximately 100°C for 30 minutes and was

so chilled. The resulting polymer was recovered by filtration, washed with fresh toluene and dried under vacuum. A <31>p nmr of the polymer gave a new, slightly broadened peak at 14.5 ppm wrt H 3 PO 4 .

Example 5

Copolymerization of (dihydroxy)phosphinylmethyl methacrylate with acrylic acid

The copolymerization from Example 2 was repeated in use

of 150 ml of H 2 O as solvent and 0.0015 g of Wako V-50 (2,2'-azobis-(2-amidinopropane) hydrochloride)j as initiator. Heating the solution to 90°C initiated an exothermic reaction. The solution was

held at 90°C for 1 hour. A p nmr for the water-soluble copolymer gave a new peak at 14.3 ppm wrt H 3 PO 4 .

Example 6 - Preparation of latex

The following ingredients were mixed in a 1 liter beaker to prepare an emulsion:

400 ml of water

48 g Triton X-200 (28% solids) (Trademark of Rohm and Haas, alkylaryl ether sulfonate - anionic surfactant)

160 g methyl methacrylate (1.6 mol)

240 g ethyl acrylate (2.4 mol)

0.8g of ammonium persulphate

In a reaction vessel consisting of a 2-liter 3-necked flask with a round bottom equipped with a cooler, addition funnel, nitrogen inlet, thermometer and a mechanical stirrer, 100 ml of prepared emulsion was placed. The flask was heated to 82°C under a nitrogen blanket. The mixture began at reflux and the temperature was raised to 90°C. When reflux began to slow, the remainder of the emulsion was added dropwise so that the vessel temperature remained at 88 to 92°C. After the addition was finished,

the temperature was raised to 97°C for one hour. The emulsion was then cooled to room temperature and filtered through a paint filter apparatus.

Example 7

Preparation of styrene-butadiene-latex incorporating (dihydroxy)-phosphinylmethyl methacrylate

(a) Emulsion polymerization was carried out as follows: initially, the reactor was charged with 73 parts by weight of water, 0.01 part by weight of pentasodium salt of (carboxymethylimino)-bis(ethylene-nitrile)tetraacetic acid (1% solution) and 0.70 weight part Kim latex (polystyrene, 270 A

(27 nm) 39.7% solids). A first flow of 62 parts by weight of styrene and 0.5 part by weight of tert.- was added to this mixture at the same time.

dodecyl mercaptan; another stream of 38 parts by weight of butadiene; a third stream of 15 parts by weight of water, 0.7 parts by weight of sodium persulfate,

0.1 part by weight of 10% ammonium hydroxide and 0.5 part by weight of sodium salt of dodecyl-sulfonated phenyl ether (45% solution); and a fourth stream of 12 parts by weight of water and 2.0 parts by weight of the disodium salt of (dihydroxy)phosphinylmethyl methacrylate. The polymerization was carried out at 90°C, and the addition time was 4 hours.

The product contained 45.2 wt% solids and had a particle diameter of 1730 Å (173 nm). (b) A modified latex was prepared as above, using 4.0 parts by weight of disodium salts of (dihydroxy)-phosphinylmethyl methacrylate. The resulting latex contained 40.6% solids by weight and the particle diameter was 1730 Å (173 nm).

The preceding latexes can be used for paper coating and

in industrial coatings.

Example fi - Spvle test on rust

A latex was prepared by the method described in example 6 from the following ingredients: 400 ml of water, 48 g of Triton X-200 (28% solids), 160 g of methyl methacrylate, 0.8 g of ammonium persulfate and 4.0 g of methacrylic acid. This latex was not an example of the invention and was included for comparison.

On a cold-rolled steel plate, it was on different parts

of the plate applied coatings of the latex prepared in example 6,

and the comparison latex. The coatings were air-dried and then heated at 150°C for one hour.

On the clear coatings obtained, X was scored, and an ampoule of water was poured over each X. After being left overnight, the part of the plate coated with the compared latex showed a high degree of rusting, while the part which was coated with the latex of Example 6 exhibited little or no rusting.

The examples show that latex containing the monomers according to this invention exhibits improved anti-corrosion properties.

Example 9 - Preparation of latex

In a 3.785 liter glass reactor equipped with an agitator and a device for monitoring the reactor temperature, an initial charge of 70 parts by weight of deionized water and 2 parts by weight of Kim latex (95% styrene, 5% acrylic acid sodium lauryl sulfate surfactant, 280 Å ( 28 nm).The reactor was purged with nitrogen, agitated and heated to 90° C. The monomer charge comprising 49.5 parts by weight methyl methacrylate, 49.5 parts by weight n-butyl acrylate and 1.0 part by weight (hydroxy)phosphinylmethyl methacrylate was added to the reactor at time = 0 minutes and for a total of 120 minutes at a feed rate of 400 cm 3 /hour The initiator charge comprising 97.56 parts by weight of deionized water, 1.22 parts by weight of NaHCO 3 and 1.22 parts by weight of Na 2 S 2 O g was added to the reactor initially at the time = 0 minutes for a total of 150 minutes at a feed rate of 123 cm^/hour.

After the addition of all initiator filling (i.e. at the time

= 150 minutes), the mixture was further agitated at 90°C under nitrogen for 30 minutes. The product contained approximately 50% solids.

The latex produced in accordance with the above method is suitable for use in industrial coatings, coatings for buildings, plastic coatings, paper coatings, adhesives and high barrier coatings. A clear coating material comprising this latex exhibited good salt spray corrosion resistance, tested by the ASTM B117 method.

Example 10

A high gloss pigmented anti-corrosive paint for metals was prepared by mixing the following ingredients at room temperature:

Urethane-based polymeric associable thickener 0.4 g.

The paint exhibited good corrosion resistance, resistance to blistering and high gloss (90 sheen at an angle of 60°).

Claims (7)

1. Latex material comprising a polymer material, characterized in that it comprises a polymerisation ion product formed from: (a) between 0.5 and 100% by weight of a (hydroxy)phosphinylalkyl acrylate, a (hydroxy)phosphinylalkyl methacrylate, a (dihydroxy)phosphinylalkyl acrylate, methacrylate or ethacrylate, or an alkali metal, alkaline earth metal or ammonium salt thereof, and (b) between 0 and 99.5% by weight of a compound containing a polymerizable 1,2-ethylenic unsaturated share. 2. Latex material according to claim 1, characterized in that the reaction product consists of between 1 and 10% by weight of (a) and between 90 and 99% by weight of (b). 3. Latex material according to claim 1 or 2, characterized in that the (hydroxy)phosphinylalkyl acrylate, the (hydroxy)phosphinylalkyl methacrylate and the alkali metal, alkaline earth metal or ammonium salt thereof conform to the formula where R 1 is hydrogen or methyl, and R 2 is hydrogen or C 1-1C alkyl 4. Latex material according to claim 1 or 2, characterized in that the (dihydroxy)phosphinyl acrylate monomer conforms to the formula or 1 2 where R is hydrogen, methyl or ethyl, R is independently selected from hydrogen and alkyl of 1-10 carbon atoms, and M<+> is an ammonium or alkali metal cation or 1/2 of an alkaline earth metal cation. 5. Process for producing a latex material according to claim 1, characterized in that it comprises copolymerizing between 0.5 and 100% by weight of monomer (a) and between 0 and 99.5% by weight of monomer (b). 6. Process for producing a latex material according to claim 5, characterized in that it comprises copolymerizing between 1 and 10% by weight of monomer (a) and between 90 and 99% by weight of monomer (b). 7. Use of a latex material as set forth in any one of claims 1-4 as an anti-corrosive paint for metals.