JPS6227083B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a polymer solution, and particularly aims to obtain a polymer solution that can form a coating film with excellent adhesion and water resistance when used as a film-forming component for paints. It is. Conventionally, a coating composition containing a copolymer in which a phosphate ester group has been introduced into a part of the side chain of a vinyl copolymer as a coating film-forming component has been disclosed in JP-A-47-26420; A conductive paint in which a copolymer of an ethylenically unsaturated compound having . However, the polymer coating films obtained by these methods are themselves highly hydrophilic, and therefore have defects such as poor water resistance, poor corrosion resistance, and poor adhesion. The present invention was completed as a result of research aimed at obtaining a film-forming polymer free of the above defects. That is, the present invention has the following general formula: (In the formula, R represents a hydrogen atom or a methyl group, and n is an integer of 1 to 6) orthophosphoric acid represented by the general formula (In the formula, R and n represent the above-mentioned meanings.) At least one kind selected from orthophosphorous acids represented by the formula: and a monoepoxy compound having no polymerizable unsaturated group are reacted in approximately equimolar amounts. 1 to 70 parts by weight of the obtained monovinyl phosphate epoxy ester compound and a styrene monomer, (meth)acrylic acid ester monomer, (meth)acrylic acid monomer, (meth)acrylamide monomer, vinylpyrrolidone, and vinyl acetate. 99 to 30 parts by weight of vinyl monomers are subjected to a copolymerization reaction in an organic liquid. The unsaturated monoesters of orthophosphoric acid or orthophosphorous acid represented by the above general formula are adducts of orthophosphoric acid or orthophosphorous acid and a monomer having a hydroxyl group and a polymerizable unsaturated group. Examples of monomers include 2-hydroxyethyl, 2-hydroxypropyl, 3-chloro-2-
Examples include acrylates or methacrylates of hydroxypropyl, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, polyethylene glycol (molecular weight 282 or less), polypropylene glycol (molecular weight 366 or less). Specific examples of such unsaturated monoesters of orthophosphoric acid or orthophosphorous acid include:
For example, Phosmer M (product name manufactured by Oil Products Co., Ltd.), Kayamer PM-2 (product name manufactured by Nippon Kayaku Co., Ltd.), Phosmer
Cl (product name manufactured by Oil and Fat Products Co., Ltd.), etc. The reaction between unsaturated monoesters of orthophosphoric acid or orthophosphorous acid and a monoepoxy compound having no polymerizable unsaturated group is carried out by heating at about 60 to 150°C for about 2 to 10 hours with stirring. I can do it. The end point of the reaction is determined by measuring the acid value.
The reaction is usually terminated when the acid value reaches about 250 or less, preferably about 200 or less. In this reaction, in order to prevent thermal polymerization of the polymerizable unsaturated group,
50 to 1000 ppm of polymerization inhibitors such as hydroquinone
It is desirable to add it. Monoepoxy compounds having no polymerizable unsaturated group that can be used in the present invention include, for example, phenyl monoglycidyl ether, monoepoxidized oil, butyl monoglycidyl ether, allyl monoglycidyl ether, 2-ethylhexyl monoglycidyl ether, methyl Examples include monoglycidyl ether, and these monoepoxy compounds having no polymerizable unsaturated group can be used alone or in combination. By reacting a monoepoxy compound that does not have a polymerizable unsaturated group with an unsaturated monoester of orthophosphoric acid or orthophosphorous acid in approximately equimolar amounts, one OH group bonded to phosphorus has 1
Moles of saturated monoepoxy compound are added to obtain a monovinyl phosphate epoxy ester compound. When a diepoxy, triepoxy compound or unsaturated epoxy compound is used as the above-mentioned epoxy compound, gelation and thickening occur significantly during the reaction process, making it impossible to obtain a uniform monovinyl phosphate epoxy ester compound. The monovinyl phosphate epoxy ester compound obtained as described above is then copolymerized with a vinyl monomer. Vinyl monomers to be copolymerized include styrene, vinyltoluene, acrylic acid, methacrylic acid, acrylic esters, methacrylic esters (such as methyl acrylate,
Ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
(2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, etc.), vinylpyrrolidone, vinyl acetate, N-methylolacrylamide, diacetone acrylamide, etc. are suitable. In the copolymerization composition, 99 to 30 parts by weight of the above vinyl monomer to 1 to 70 parts by weight of the monovinyl phosphate epoxy ester compound has adhesive strength,
It is preferable in terms of exhibiting sufficient rust prevention ability and maintaining good water resistance. The copolymerization reaction takes place in an organic liquid with 2.
Azo polymerization initiators such as 2'-azoisobutyronitrile and 2,2'-azobis(2,4-dimethylvaleronitrile), peroxides such as lauryl peroxide, benzoyl peroxide, and tert-butyl peroctoate. It is polymerized using a physical polymerization initiator. The concentration of the polymerization initiator is preferably 0.5 to 10 parts by weight per 100 parts by weight of the vinyl monomer. The reaction temperature is 60-160°C. It is also possible to obtain a polymer solution by placing an organic liquid in a reaction container and adding the monovinyl phosphoric acid epoxy ester compound, the entire amount of vinyl monomer, and a polymerization initiator, and conducting the reaction for 1 to 15 hours. A mixture of the acid epoxy ester compound (whole amount or a portion may be mixed with the vinyl monomer) and the polymerization initiator is added dropwise over 1 to 7 hours, and then the reaction is continued for 2 to 7 hours to polymerize. It is also possible to obtain a combined solution. The polymer solution thus obtained is particularly suitable as a film-forming component for paints, but can also be used for molded products, adhesives, fillers, and the like. The polymer solution of the present invention can be used as it is, but if necessary, a colorant, a plasticizer, a curing agent, etc. can be mixed therein. Colorants include dyes, organic pigments, and inorganic pigments. Examples of the plasticizer include known ones, such as low molecular weight plasticizers such as dimethyl phthalate and dioctyl phthalate, and high molecular weight plasticizers such as vinyl polymer plasticizers and polyester plasticizers. Examples of hardening agents include crosslinking agents such as amino resins and epoxy resins. By introducing a material having a carboxyl group into the copolymer composition, neutralizing the carboxyl group with ammonia or amines, and replacing the organic liquid of the polymer solution of the present invention with water, a water-soluble type or a water-dispersed type can be obtained. It is also possible to do so. The polymer solution of the present invention has the following characteristics compared to conventional vinyl polymer paint resins, polyester paint resins, epoxy paint resins, polyvinyl butyral paint resins, phenolic paint resins, etc.
Excellent coating properties such as adhesion, rust prevention, water resistance, and weather resistance. Examples will be described below. Parts mean parts by weight. Example 1 (Synthesis of monovinyl phosphate epoxy ester compound solution (1)) Toluene 500 parts Isopropyl alcohol 410 parts Orthophosphoric acid-2-hydroxyethyl methacrylate monoester 420 parts Cardiular E (monoepoxidized oil) 490 parts Hydroquinone 0.5 part or more The mixture was placed in a second flask equipped with a stirrer and a thermometer, and the mixture was reacted at 100°C for 5 hours with stirring.
The reaction end point was when the acid value reached 130. It was a clear solution with a non-volatile content of 50 wt.%. (Synthesis of polymer solution) Monovinyl phosphate epoxy ester compound solution (1)
100 parts styrene 450 parts n-butyl acrylate 450 parts methacrylic acid 50 parts 2,2'-azoisobutyronitrile 0.5 part The above mixture was added dropwise over 3 hours to a flask containing 500 parts of toluene and 450 parts of isopropanol under reflux. After dropping, aging was carried out for 5 hours. The resulting liquid was clear;
Gardner viscosity (25℃) at non-volatile content of 50wt.% is
It was Z-4. Example 2 (Synthesis of monovinyl phosphate epoxy ester compound solution (2)) Cellosolve acetate 720 parts Orthophosphoric acid-2-hydroxyethyl methacrylate monoester 420 parts Phenyl glycidyl ether 300 parts Hydroquinone 0.4 parts The mixture was placed in a second flask and reacted at 100°C for 4 hours with stirring.
The end point of the reaction was when the acid value reached 160. It was a clear solution with a non-volatile content of 50 wt.%. (Synthesis of polymer solution) Monovinyl phosphate epoxy ester compound solution (2)
200 parts styrene 400 parts 2-hydroxyethyl methacrylate 100 parts n-butyl acrylate 350 parts methacrylic acid 50 parts 2,2'-azoisobutyronitrile 50 parts The above mixture was mixed with xylene 500 parts isopropanol in a flask in which 400 parts was refluxed. The solution was added dropwise over a period of 3 hours, and aged for 5 hours after the addition. The resulting liquid was clear;
Non-volatile content is 50wt% and Gardner viscosity (25℃) is H
It was hot. Example 3 (Synthesis of monovinyl phosphoric acid epoxy ester compound solution (3)) Cellosolve acetate 764 parts Orthophosphoric acid-2-hydroxyethyl acrylate monoester 392 parts 2-ethylhexyl glycidyl ether 372 parts Hydroquinone 0.4 parts The above was mixed with a stirrer and a thermometer. The mixture was placed in a No. 2 flask and reacted at 100°C for 6 hours with stirring.
The end point of the reaction was when the acid value reached 150. It was a clear solution with a non-volatile content of 50 wt%. (Synthesis of polymer solution) Monovinyl phosphate epoxy ester compound solution (3)
300 parts styrene 300 parts n-butyl acrylate 400 parts methyl methacrylate 100 parts methacrylic acid 50 parts ditertiary butyl peroxide 5 parts The above mixture was added dropwise over 4 hours to a flask containing 500 parts of toluene and 350 parts of n-butanol under reflux. After dropping, aging was carried out for 5 hours. The resulting liquid was transparent, had a non-volatile content of 50 wt.%, and had a Gardner viscosity (at 25°C) of Z-
It was 5. Example 4 In place of styrene, n-butyl acrylate and methacrylic acid monomers in Example 1 (synthesis of polymer solution), 250 parts of vinyl acetate and 250 parts of styrene were used.
A polymer solution was obtained in the same manner as in Example 1 except that 250 parts of methyl methacrylate and 200 parts of vinylpyrrolidone were used. The resulting liquid was transparent, had a non-volatile content of 50 wt.%, and had a Gardner viscosity (at 25°C) of Z-
It was 5. Example 5 50 parts of methacrylamide was used in place of 50 parts of methacrylic acid in Example 1 (synthesis of polymer solution), and this methacrylamide was mixed in advance in a flask in which 500 parts of toluene and 450 parts of isopropanol were refluxed. A polymer solution was obtained in the same manner as in Example 1 except for this. The resulting liquid is clear and contains no volatile components.
At 50 wt.%, the Gardner viscosity (25°C) was Z-2. Comparative Example 1 Orthophosphoric acid-2-hydroxyethyl methacrylate monoester 25 parts Styrene 455 parts N-butyl acrylate 470 parts Methacrylic acid 50 parts 2.2'-Azoisobutyronitrile 5 parts The above mixture was mixed with toluene 500 parts Isopropanol 500 parts was added dropwise over 3 hours into a refluxing flask, and aged for 5 hours after the addition. The resulting liquid was transparent, had a non-volatile content of 50 wt.%, and had a Gardner viscosity (at 25°C) of Z-
It was 5. Comparative Example 2 Styrene 450 parts n-butyl acrylate 500 parts Methacrylic acid 50 parts 2,2'-azoisobutyronitrile 5 parts The above mixture was added dropwise over 3 hours into a flask containing 500 parts toluene and 500 parts isopropanol. After dropping, aging was carried out for 5 hours. The resulting liquid was clear;
Non-volatile content is 50wt.% and Gardner viscosity (25℃) is Z
It was -3. Comparative Example 3 Orthophosphoric acid-2-hydroxyethyl methacrylate monoester 60 parts Styrene 450 parts 2-hydroxyethyl methacrylate 100 parts n-butyl acrylate 340 parts Methacrylic acid 50 parts 2.2'-Azoisobutyronitrile 50 parts Mixture of the above was added dropwise over 3 hours into a flask in which 500 parts of xylene and 500 parts of isopropanol were refluxed, and the mixture was aged for 5 hours after the addition. The resulting liquid was clear;
Gardner viscosity (25℃) at non-volatile 50wt.% is
It was I. Comparative Example 4 Styrene 500 parts 2-hydroxyethyl methacrylate 100 parts n-butyl acrylate 350 parts Methacrylic acid 50 parts The above mixture was added dropwise over 3 hours into a flask in which 500 parts xylene and 500 parts isopropanol were refluxed. It was matured. The resulting liquid was clear;
Gardner viscosity (25℃) at non-volatile content of 50wt.% is
It was G. A coating film was formed using the polymer solutions obtained in the above Examples and Comparative Examples, and a salt spray resistance test was conducted. The results are shown below.

[Table] For Examples 1 and 3 and Comparative Examples 1 and 2, the test was carried out after applying the coating to a polished mild steel plate to a dry film thickness of 20 μm and drying it at room temperature for 2 days. For Comparative Examples 3 and 4, 30 wt. % of commercially available butylated melamine resin was applied so that the film thickness after baking was 20 μm, and the test was conducted after baking at 140° C. for 20 minutes. The adhesive deterioration width of the cut part is measured by cutting a cut into the test coating with a razor and performing a cellophane adhesive tape peeling test on the cut part after salt spraying.The presence or absence of rust refers to pitting after salt spray, other This is an observation of the state of rust formation.

Claims (1)

[Claims] 1. General formula (In the formula, R represents a hydrogen atom or a methyl group, and n is an integer of 1 to 6) orthophosphoric acid represented by the general formula (In the formula, R and n represent the above-mentioned meanings) At least one kind selected from orthophosphorous acids represented by the above and a monoepoxy compound having no polymerizable unsaturated group are reacted in approximately equimolar amounts. 1 to 70 parts by weight of the obtained monovinyl phosphate epoxy ester compound and a styrene monomer, (meth)acrylic acid ester monomer, (meth)acrylic acid monomer, (meth)acrylamide monomer, vinylpyrrolidone, and vinyl acetate. A method for producing a polymer solution, which comprises copolymerizing 99 to 30 parts by weight of a vinyl monomer in an organic liquid.