JP5077849B2 - Method for producing acrylic copolymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an acrylic copolymer by which temperature control during production is easily performed and the acrylic copolymer can be efficiently produced in a short time. <P>SOLUTION: The method for producing an acrylic copolymer includes raising the temperature of an acrylic monomer mixture containing acrylic monomers containing an acrylic monomer represented by the structural formula (wherein, R<SB>1</SB>represents a hydrogen atom or a methyl group; and R<SB>2</SB>represents 1-12C alkyl group), an &alpha;-methylstyrene dimer, and an organic azo-based polymerization initiator in an amount of 0.02-1.00 mol to 1.0 mol of the &alpha;-methylstyrene dimer to a radical polymerization temperature of the acrylic monomers in 30-600 min. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for producing an acrylic copolymer, which can easily produce an acrylic copolymer in a short time, with easy temperature control during production.

  Acrylic resins are abundant in the types of acrylic monomers that are used as raw materials, and the physical and chemical properties such as adhesion, adhesion, hardness, transparency, light resistance, weather resistance, and chemical resistance are optionally controlled. It can be used for a wide range of applications such as optical coatings for displays, lenses, optical films, adhesives and adhesives used in these, paints, sealing materials, paper strength enhancers, dental materials, aircraft and automotive parts And used.

  In recent years, technology development of living radical polymerization, which is a precise polymerization control technology, has progressed, and block copolymers and graft copolymers have been produced. Applications and development of applications as high-functional polymers such as medical fields and high-sensitivity sensors Is underway.

  Acrylic resins generally generate a large amount of heat during polymerization and become more viscous as the polymerization progresses, so industrially compared heat removal such as solution polymerization, emulsion polymerization, and suspension polymerization using water or an organic solvent as a medium. It is often manufactured by an easy method. Further, when used for special purposes such as casting, it may be used as a partially polymerized syrup.

  There has been proposed a method for producing an acrylic partial polymer in which heat removal in a reaction system can be easily controlled even in the case of radical polymerization by heat in the absence of a solvent for an acrylic monomer (see Patent Document 1). Although it is said that radical polymerization is performed in the absence of a solvent, the technique proposed in Patent Document 1 is compatible with an acrylic monomer and has little polymerization inhibition, such as hydrogen of an alcohol-modified dicyclopentadiene resin. , A rosin containing 40% by weight or more of a rosin component having a tetrahydroabietic acid type skeleton, a derivative of the rosin, and an acrylic monomer in the presence of a tackifying resin. This technique is not suitable for the purpose of obtaining acrylic resin. Therefore, the use of the manufactured acrylic resin is limited to the pressure-sensitive adhesive.

  Moreover, in patent document 1, although the kind of acrylic monomer is not specifically limited, it is inevitable that it is practically restricted by compatibility with the tackifier resin, and the produced acrylic resin is also included. It is easily guessed that the presence of the tackifying resin similarly applies a brake at the stage where the physical properties and chemical properties are further improved.

2,4-diphenyl-4-methyl-1-pentene (= α-methylstyrene dimer), radically polymerized ethylenically unsaturated compound (= acrylic monomer) having a methacryloyl group in the presence of a radical polymerization initiator A method for producing a block copolymer has been proposed (see Patent Document 2). In the technique proposed in Patent Document 2, the amount of 2,4-diphenyl-4-methyl-1-pentene (weight ratio) and the amount of polymerization initiator (weight ratio) with respect to the acrylic monomer are limited. The relationship between the amount of 2,4-diphenyl-4-methyl-1-pentene (number of moles) and the amount of polymerization initiator (number of moles) is not defined. In Patent Document 2, no consideration is given to stirring and heat removal of polymerization heat, which are more important in producing an acrylic resin and are fundamental safety issues. In Patent Document 2, it is proposed to produce an acrylic resin by solution polymerization that is easy to stir and remove heat. Even if a block copolymer is produced according to Patent Document 2, it takes a lot of energy and labor to remove the organic solvent from the acrylic resin produced in the form of a solution of the organic solvent and to take out only the acrylic resin. . At the same time, the yield is greatly reduced. From the viewpoint of LCA (Life Cycle Assessment) and PRTR Law (Pollutant Release and Transfer Register; a law regarding the grasp of emissions of specific chemicals to the environment and promotion of improvement in management), it is not a practical means.
JP 2003-128714 A JP 2000-169531 A

  Provided is a method for producing an acrylic copolymer which solves problems in production including stirring and heat removal from an industrial standpoint and dispels safety and disaster prevention concerns, which are the most important issues.

  The present invention is represented by the following structural formula.

(Here, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 1 to 12 carbon atoms.)
Acrylic monomer including acrylic monomer, represented by the following structural formula

an acrylic monomer mixture containing α-methylstyrene dimer and 0.02 to 1.00 mol of an organic azo polymerization initiator with respect to 1.0 mol of α-methylstyrene dimer was charged at 5 to 40 ° C .; This is a method for producing an acrylic copolymer in which a bulk radical polymerization is carried out at 80 to 100 ° C. after raising the temperature to the radical polymerization temperature of the acrylic monomer in 30 to 600 minutes.

  According to the method for producing an acrylic copolymer of the present invention, it is possible to solve the problems in safety and disaster prevention including avoidance of the process leading to rapid polymerization reaction and runaway reaction, control thereof, stirring and heat removal.

  Further, the acrylic copolymer of the present invention can be further modified to be used as a prepolymer useful for producing a functional copolymer such as a block copolymer as a polymer alloy or a high-sensitivity sensor.

  The present invention is represented by the following structural formula.

(Here, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 1 to 12 carbon atoms.)
Acrylic monomer including acrylic monomer, represented by the following structural formula

an acrylic monomer mixture containing α-methylstyrene dimer and 0.02 to 1.00 mol of an organic azo polymerization initiator with respect to 1.0 mol of α-methylstyrene dimer was charged at 5 to 40 ° C .; This is a method for producing an acrylic copolymer in which a bulk radical polymerization is carried out at 80 to 100 ° C. after raising the temperature to the radical polymerization temperature of the acrylic monomer in 30 to 600 minutes.

  In the method for producing an acrylic copolymer of the present invention, it is represented by the following structural formula.

(Here, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 1 to 12 carbon atoms.)
Acrylic monomer is used.

  In the method for producing an acrylic copolymer of the present invention, it is represented by the following structural formula.

(Here, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 1 to 12 carbon atoms.)
Acrylic monomers include methyl acrylate, ethyl acrylate, n-butyl acrylate, propyl acrylate, isobutyl acrylate, tertiary butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, methacryl (Meth) acrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, propyl methacrylate, isobutyl methacrylate, tertiary butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, etc. A mer is exemplified. In the method for producing an acrylic copolymer of the present invention, these acrylic monomers may be used alone or in a mixture of two or more.

  In the method for producing an acrylic copolymer of the present invention, in addition to these acrylic monomers, preferably, a carboxyl group-containing acrylic monomer such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid, 2-hydroxy acrylate Ethyl, hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, poly Hydroxyl-containing acrylic monomers such as tetramethylene glycol mono (meth) acrylate, epoxy such as glycidyl acrylate, glycidyl methacrylate, methyl glycidyl methacrylate, p-vinylbenzyl glycidyl ether Group-containing acrylic monomers, acrylic monomers derived from dicyclopentadiene such as dicyclopentanyloxyethyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentanyloxyethyl methacrylate, dicyclopentenyloxyethyl methacrylate, (Meth) acrylic acid esters such as allyl acrylate, allyl methacrylate, benzyl methacrylate, tetrahydrofurfuryl methacrylate, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, 4-methacryloyloxy- Tertiary amino group-containing acrylic monomers such as 2,2,6,6-tetramethylpiperidine and 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine, 3-methacryloyloxye Urea group-containing acrylic monomers such as ruthenium urea, acryloylmorpholine, methacryloylmorpholine, acrylamide, N, N-dimethylacrylamide, ethylacrylamide, isopropylacrylamide, N-methylolacrylamide, 2-hydroxyethylacrylamide, N, N-dimethyl Aminopropylacrylamide, N, N-diethylaminopropylacrylamide, methacrylamide, N, N-dimethylmethacrylamide, ethylmethacrylamide, isopropylmethacrylamide, N-methylolmethacrylamide, 2-hydroxyethylmethacrylamide, N, N-dimethylamino Amide group-containing acrylic monomers such as propylmethacrylamide and N, N-diethylaminopropylmethacrylamide You can use. In the method for producing an acrylic copolymer of the present invention, these acrylic monomers may be used alone or in a mixture of two or more.

  In the method for producing an acrylic copolymer of the present invention, α-methylstyrene dimer having the following structural formula

That is, 2,4-diphenyl-4-methyl-1-pentene is used.

  As α-methylstyrene dimer, that is, 2,4-diphenyl-4-methyl-1-pentene, for example, it is manufactured by Goi Kasei Co., Ltd., Honshu Chemical Industry Co., Ltd., Asahi Kasei Finechem Co., Ltd. Can be arbitrarily selected and used.

  In the manufacturing method of the acrylic copolymer of this invention, it is 0.02-1.00 mol with respect to 1.0 mol of alpha-methylstyrene dimer, Preferably it is 0.05-1.00 mol, More preferably, it is 0.00. 10 to 0.83 mol of organic azo polymerization initiator is used.

  In the method for producing an acrylic copolymer of the present invention, the polymerization rate is appropriate by using 0.02 to 1.00 mol of an organic azo polymerization initiator with respect to 1.0 mol of α-methylstyrene dimer. Therefore, stirring and heat removal during production are facilitated, and it is possible to safely carry out the production work of the acrylic copolymer.

  In the method for producing an acrylic copolymer of the present invention, when the amount of the organic azo polymerization initiator used is less than 0.02 mol with respect to 1.0 mol of α-methylstyrene dimer, polymerization of the acrylic monomer is performed. The speed is slow, the manufacturing time is long, and there are few industrial advantages. When the amount of the organic azo polymerization initiator used exceeds 1.00 mol, rapid and intense heat generation frequently occurs during the production of the acrylic copolymer, making it difficult to control the polymerization temperature.

  In the method for producing an acrylic copolymer of the present invention, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) (“Wako Pure Chemical Industries” “V” is preferable as the organic azo polymerization initiator. -70 ") (melting point 50-96 ° C, molecular weight 308.4, 10 hour half-life temperature 30 ° C), 2,2'-azobis (2,4-dimethylvaleronitrile) (" V-65 manufactured by Wako Pure Chemical Industries, Ltd.) ”) (Melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), 2,2′-azobis (2-methylpropionitrile) (“ V-60 ”manufactured by Wako Pure Chemical Industries, Ltd.) ( Melting point 100 to 103 ° C., molecular weight 164.2, 10 hour half-life temperature 65 ° C., 2,2′-azobis (2-methylbutyronitrile) (“V-59” manufactured by Wako Pure Chemical Industries) (melting point 48 to 52 ° C., molecular weight 192.3, 10 hour half-life temperature 67 ° C.), 1,1′-azobis (cyclohexane-1-carbonitrile) (“V-40” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 113 to 115 ° C., molecular weight: 244.3, 10 hour half-life temperature: 88 ° C.) , 1-[(1-cyano-1-methylethyl) azo] formamide (“V-30” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 76-78 ° C., molecular weight: 140.1, 10 hour half-life temperature: 104 ° C.) 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide} (“VA-080” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 150 to 155 , Molecular weight 408.5, 10 hour half-life temperature 80 ° C.), 2,2′-azobis {2-methyl-N- [2- (1-hydroxybutyl)]-propionamide} (manufactured by Wako Pure Chemical Industries, Ltd. VA-085 ") (melting point 7 9.5 ° C., molecular weight 344.5, 10 hour half-life temperature 85 ° C.), 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] (“VA manufactured by Wako Pure Chemical Industries, Ltd.” -086 ") (melting point 140-145 ° C, molecular weight 288.4, 10 hour half-life temperature 86 ° C), 2,2'-azobis [N- (2-propenyl) -2-methylpropionamide] (Wako Pure Chemical Industries, Ltd.) “VF-096” manufactured by Kogyo Co., Ltd. (melting point: 67-71 ° C., molecular weight: 280.4, 10 hour half-life temperature: 96 ° C.), 2,2′-azobis (N-butyl-2-methylpropionamide) (Wako Pure Chemical Industries, Ltd.) “VAm-110” manufactured by Kogyo Co., Ltd. (melting point 65 ° C., molecular weight 312.5, 10 hour half-life temperature 110 ° C.), 2,2′-azobis (N-cyclohexyl-2-methylpropionamide) (manufactured by Wako Pure Chemical Industries, Ltd.) "VAm-11 ”(Melting point 116 ° C., molecular weight 364.5, 10 hour half-life temperature 111 ° C.), dimethyl 2,2′-azobis (2-methylpropionate) (“ V-601 ”manufactured by Wako Pure Chemical Industries, Ltd.) (melting point) 22-28 ° C., molecular weight 230.3, 10 hour half-life temperature 66 ° C.), 2,2′-azobis (2,4,4-trimethylpentane) (“VR-110” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 23 ˜24 ° C., molecular weight 254.5, 10 hour half-life temperature 110 ° C.) and the like.

  In the method for producing an acrylic copolymer of the present invention, the organic azo polymerization initiator may be used alone or in a mixture of two or more.

  In the method for producing an acrylic copolymer of the present invention, the melting point of the organic azo polymerization initiator is preferably 20 to 105 ° C. In the method for producing an acrylic copolymer of the present invention, the melting point of the organic azo polymerization initiator is more preferably 20 to 100 ° C, and further preferably 20 to 80 ° C. In the method for producing an acrylic copolymer of the present invention, when the melting point of the organic azo polymerization initiator is 20 to 105 ° C., the polymerization rate tends to be high and the production time tends to be shortened. In addition, there is no tendency to suddenly generate heat or abnormal temperature rise, and it is easy to control the polymerization temperature.

  In the method for producing an acrylic copolymer of the present invention, as an organic azo polymerization initiator having a melting point of 20 to 105 ° C., 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) ( “V-70” manufactured by Wako Pure Chemical Industries, Ltd. (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure) “V-65” manufactured by Yakuhin Kogyo Co., Ltd. (melting point: 45-70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), 2,2′-azobis (2,4-methylpropionitrile) (Wako Pure Chemical Industries, Ltd.) “V-60” manufactured by Kogyo Co., Ltd. (melting point: 100 to 103 ° C., molecular weight: 164.2, 10 hour half-life temperature: 65 ° C.), 2,2′-azobis (2-methylbutyronitrile) (manufactured by Wako Pure Chemical Industries, Ltd. V-59 ") (melting point 48-52 ° C, molecular weight 1 2.3, 10-hour half-life temperature 67 ° C.), 1-[(1-cyano-1-methylethyl) azo] formamide (“V-30” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 76-78 ° C., molecular weight 140.1, 10 hour half-life temperature 104 ° C.), dimethyl 2,2′-azobis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 22-28 ° C., molecular weight 230. 3, 10-hour half-life temperature 66 ° C.), 2,2′-azobis (2,4,4-trimethylpentane) (“VR-110” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 23-24 ° C., molecular weight: 254.5 10 hours half-life temperature 110 ° C.), 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 67-71 ° C., Molecular weight 280.4, 10 hour half-life temperature 96 ° C Etc. are exemplified.

  In the method for producing an acrylic copolymer of the present invention, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) is more preferably used as an organic azo polymerization initiator having a melting point of 20 to 80 ° C. ) (“V-70” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) ( “V-65” manufactured by Wako Pure Chemical Industries, Ltd. (melting point: 45-70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), 2,2′-azobis (2-methylbutyronitrile) (Wako Pure Chemical Industries, Ltd.) “V-59” manufactured by Kogyo Co., Ltd. (melting point: 48 to 52 ° C., molecular weight: 192.3, 10 hour half-life temperature: 67 ° C., dimethyl 2,2′-azobis (2-methylpropionate) (manufactured by Wako Pure Chemical Industries, Ltd.) V-601 ") (melting point 22-28 ° C, Molecular weight 230.3, 10 hour half-life temperature 66 ° C.), 2,2′-azobis (2,4,4-trimethylpentane) (“VR-110” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 23-24 ° C., molecular weight 254.5, 10 hours half-life temperature 110 ° C.), 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) 71 ° C., molecular weight 280.4, 10 hour half-life temperature 96 ° C.) and the like.

  In the method for producing an acrylic copolymer of the present invention, when the melting point of the organic azo polymerization initiator is 20 to 80 ° C., the polymerization rate is controlled more appropriately, the polymerization temperature is easily controlled, and the production time is reduced. This tends to be balanced and is desirable. Furthermore, the manufacturing time can be shortened, and the manufacturing merit tends to increase. In addition, the polymerization temperature of the acrylic copolymer can be lowered to 98 ° C. or lower, and there is a tendency that functional groups having reactivity with each other can be simultaneously copolymerized.

  In the method for producing an acrylic copolymer of the present invention, the 10-hour half-life temperature of the organic azo polymerization initiator is preferably 20 to 100 ° C, more preferably 30 to 100 ° C, and further preferably 30 to 80. It is desirable to be at ° C. In the method for producing an acrylic copolymer of the present invention, when the organic azo polymerization initiator has a 10-hour half-life temperature of 20 to 100 ° C., the polymerization reaction is smooth and the molecular weight distribution (weight average molecular weight / number average molecular weight) is. In some cases, the manufacturing time can be reduced. Here, in the method for producing an acrylic copolymer of the present invention, the 10-hour half-life temperature refers to a temperature at which the concentration of the organic azo polymerization initiator is reduced by half in 10 hours, and a manufacturer of the organic azo polymerization initiator, for example, The values published by Wako Pure Chemical Industries, Ltd. were adopted (reference material: Wako Pure Chemical Industries, Ltd.-Chemicals Division Catalog- “Azo Polymerization Initiators”).

  In the method for producing an acrylic copolymer of the present invention, 2,2′-azobis (4-methoxy-2,4-dimethyl) is preferably used as the organic azo polymerization initiator having a 10-hour half-life temperature of 20 to 100 ° C. Valeronitrile) (“V-70” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) ) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), 2,2′-azobis (2-methylpropionitrile) (Wa “V-60” (manufactured by Kojun Pharmaceutical Co., Ltd.) (melting point: 100 to 103 ° C., molecular weight: 164.2, 10 hour half-life temperature: 65 ° C.), 2,2′-azobis (2-methylbutyronitrile) (Wako Pure Chemical Industries, Ltd.) "V-59" (melting point 48-52 ° C) Molecular weight 192.3, 10 hour half-life temperature 67 ° C.), 1,1′-azobis (cyclohexane-1-carbonitrile) (“V-40” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 113-115 ° C., molecular weight 244. 3, 10-hour half-life temperature 88 ° C.), 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide} (manufactured by Wako Pure Chemical Industries, Ltd. VA-080 ") (melting point 150-155 ° C, molecular weight 408.5, 10 hour half-life temperature 80 ° C), 2,2'-azobis {2-methyl-N- [2- (1-hydroxybutyl)]- Propionamide} (“VA-085” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 79.5 ° C., molecular weight: 344.5, 10-hour half-life temperature: 85 ° C.), 2,2′-azobis [2-methyl-N— ( 2-hydroxyethyl) -propyl Pionamide] (“VA-080” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 140-145 ° C., molecular weight 288.4, 10 hour half-life temperature 86 ° C.), 2,2′-azobis [N- (2-propenyl)- 2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 67-71 ° C., molecular weight: 280.4, 10-hour half-life temperature: 96 ° C.), dimethyl 2,2′-azobis (2-methyl Propionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 22 to 28 ° C., molecular weight: 230.3, 10 hour half-life temperature: 66 ° C.) and the like.

  In the method for producing the acrylic copolymer of the present invention, the molecular weight of the organic azo polymerization initiator is preferably 190 to 320, more preferably 200 to 310, and still more preferably 210 to 310. In the method for producing an acrylic copolymer of the present invention, when the molecular weight of the organic azo polymerization initiator is 190 to 320, the polymerization reaction proceeds smoothly and the polymerization temperature tends to be easily controlled, and the production time is shortened. There is a tendency to peel off. At the same time, there is a tendency that heat generation during production is reduced and production can be performed more safely.

  In the method for producing an acrylic copolymer of the present invention, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) (sum) is preferably used as the organic azo polymerization initiator having a molecular weight of 190 to 320. “V-70” manufactured by Kojun Pharmaceutical Co., Ltd. (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), 2,2′-azobis (2-methylpropionitrile) (manufactured by Wako Pure Chemical Industries, Ltd. V-60 ") (melting point 100-103 ° C, molecular weight 164.2, 10 hour half-life temperature 65 ° C), 2,2'-azobis (2-methylbutyronitrile) (" V-59 manufactured by Wako Pure Chemical Industries, Ltd.) ") (Melting point 48-52 ° C, molecular weight 19 .3, 10-hour half-life temperature 67 ° C.), 1,1′-azobis (cyclohexane-1-carbonitrile) (“V-40” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 113 to 115 ° C., molecular weight 244.3, 10-hour half-life temperature 88 ° C.), 1-[(1-cyano-1-methylethyl) azo] formamide (“V-30” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 76-78 ° C., molecular weight 140.1, 10-hour half-life temperature of 104 ° C.), 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] (“VA-086” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 140 to 145 ° C. , Molecular weight 288.4, 10 hour half-life temperature 86 ° C.), 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) 67-71 ° C., molecular weight 280 .4, 10-hour half-life temperature 96 ° C.), 2,2′-azobis (N-butyl-2-methylpropionamide) (“VAm-110” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 65 ° C., molecular weight 312.5 10-hour half-life temperature 110 ° C.), dimethyl 2,2′-azobis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 22-28 ° C., molecular weight 230.3, 10 Time half-life temperature 66 ° C.), 2,2′-azobis (2,4,4-trimethylpentane) (“VR-110” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 23-24 ° C., molecular weight: 254.5, 10 hours A half-life temperature of 110 ° C.).

  In the method for producing an acrylic copolymer of the present invention, the organic azo polymerization initiator is preferably all conditions having a melting point of 20 to 105 ° C., a 10-hour half-life temperature of 20 to 100 ° C., and a molecular weight of 190 to 320. It is even more desirable to satisfy In the method for producing an acrylic copolymer of the present invention, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) (Wako Pure Chemicals) is used as an organic azo polymerization initiator that satisfies all these conditions. “V-70” manufactured by Kogyo Co., Ltd. (melting point: 50 to 96 ° C., molecular weight 308.4, 10 hour half-life temperature 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd.) “V-65”) (melting point: 45 to 70 ° C., molecular weight: 248.4, 10-hour half-life temperature: 51 ° C.), 2,2′-azobis (2-methylpropionitrile) (“V- 60 ") (melting point 100-103 ° C, molecular weight 164.2, 10 hour half-life temperature 65 ° C), 2,2'-azobis (2-methylbutyronitrile) (" V-59 "manufactured by Wako Pure Chemical Industries, Ltd.) (Melting point 48-52 ° C., molecular weight 192.3, 1 Time half-life temperature 67 ° C.), 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 67-71 ° C., molecular weight 280 4, 10-hour half-life temperature 96 ° C.), dimethyl 2,2′-azobis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 22-28 ° C., molecular weight 230.3) And a 10-hour half-life temperature of 66 ° C.).

  Among these, in the method for producing an acrylic copolymer of the present invention, in particular, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) (“V-70” manufactured by Wako Pure Chemical Industries, Ltd.) (Melting point 50-96 ° C., molecular weight 308.4, 10 hour half-life temperature 30 ° C.), 2,2′-azobis (2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 45-70 ° C., molecular weight 248.4, 10 hour half-life temperature 51 ° C.), 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] (“VF-096” manufactured by Wako Pure Chemical Industries, Ltd.) ”) (Melting point 67-71 ° C., molecular weight 280.4, 10 hour half-life temperature 96 ° C.), dimethyl 2,2′-azobis (2-methylpropionate) (“ V-601 ”manufactured by Wako Pure Chemical Industries, Ltd.) (Melting point 22-28 ° C., molecular weight 230.3, A 10 hour half-life temperature of 66 ° C.) is recommended. The polymerization temperature is easily controlled, the polymerization rate is high, the molecular weight distribution is narrowed, and the production time tends to be shortened.

  In the method for producing an acrylic copolymer of the present invention, in order to more safely control the polymerization temperature, the organic azo polymerization initiator is preferably 0.05 to 5 with respect to 100 parts by weight of the acrylic monomer. It is desirable to use parts by weight, more preferably 0.08 to 3 parts by weight, and still more preferably 0.10 to 2.5 parts by weight. In the method for producing an acrylic copolymer of the present invention, when the amount of the organic azo polymerization initiator used is 0.05 to 5 parts by weight, an abnormal polymerization reaction and rapid heat generation tend to be less likely to occur, and There is also a tendency that the production time of the acrylic copolymer is sufficiently established industrially.

  In the method for producing an acrylic copolymer of the present invention, an acrylic monomer mixture containing an acrylic monomer, an α-methylstyrene dimer, and an organic azo polymerization initiator is added to an acrylic monomer polymerization temperature of 30 to 600. The acrylic copolymer is produced by raising the temperature in minutes. In the method for producing an acrylic copolymer of the present invention, preferably, an acrylic monomer mixture containing an acrylic monomer, an α-methylstyrene dimer, and an organic azo polymerization initiator in an acrylic resin production apparatus, It is desirable that the acrylic copolymer is produced by batch charging and raising the temperature to the polymerization temperature of the acrylic monomer for 30 to 600 minutes, preferably 45 to 600 minutes, more preferably 60 to 300 minutes. . Not only can the manufacturing process be simplified, the polymerization temperature can be easily controlled, and the manufacturing time tends to be greatly shortened.

  In the method for producing an acrylic copolymer of the present invention, when the temperature rising time is less than 30 minutes, the polymerization reaction becomes a runaway reaction during the temperature rising, which is a safety problem. When the temperature rising time exceeds 600 minutes, the viscosity becomes high during the temperature rising, and stirring becomes difficult. Moreover, the manufacturing time tends to be long, and there are few industrial advantages.

In the method for producing an acrylic copolymer of the present invention, an acrylic monomer mixture containing an acrylic monomer, an α-methylstyrene dimer, and an organic azo polymerization initiator, which are preferably charged all together in an acrylic resin production apparatus, is charged. when the temperature is 5 to 40 ° C., good Mashiku is Ru 5 to 35 ° C. der. In the method for producing an acrylic copolymer of the present invention, the charging temperature of the acrylic monomer mixture is the rise of the acrylic monomer mixture containing the acrylic monomer, α-methylstyrene dimer, and organic azo polymerization initiator. Refers to the temperature immediately before starting the warming operation.

In the method of manufacturing the acrylic copolymer of the present invention, the polymerization temperature, Ru 8 0 to 100 ° C. der.

  In the method for producing an acrylic copolymer of the present invention, more preferably, when the polymerization temperature is 83 to 98 ° C., the acrylic copolymer reacts with a carboxyl group and a hydroxyl group, a carboxyl group and an epoxy group, and the like. When introducing functional groups that have the property, the reaction between the functional groups is suppressed, and there is no abnormal thickening or gelation during the production of the acrylic copolymer. There is a tendency that the polymer can be produced more safely and in a short time.

  Similarly, in the method for producing an acrylic copolymer of the present invention, an acrylic copolymer having a carboxyl group in its molecule is used as a prepolymer, and in the presence of this prepolymer, an epoxy group is present in the molecule such as glycidyl methacrylate. AB block copolymer comprising an acrylic copolymer (A) having a carboxyl group in the molecule and an acrylic copolymer (B) having an epoxy group in the molecule The reaction between functional groups is suppressed in the production of an acrylic copolymer, and no abnormal thickening or gelation occurs during the production of the acrylic copolymer. As a polymer alloy or stimuli-responsive polymer material, or carboxyl Acrylic copolymers that have selective adhesive properties using epoxy groups and epoxy groups, are compatible with different materials, and polymer materials, and are designed to be more functional. Trend can be seen which can be prepared in time.

In the method of manufacturing the acrylic copolymer of the present invention, A acrylic copolymer prepared convenience, purification of the prepared acrylic copolymer, ease of handling of the separation or the like, to produce in mass form radical polymerization.

  In the method for producing an acrylic copolymer of the present invention, bulk radical polymerization is one of methods used for radical copolymerization of a monomer having a vinyl group such as an acrylic monomer or a styrene monomer. Without using a solvent, polymerization is carried out by heating only a monomer having a vinyl group such as an acrylic monomer or a styrene monomer, or by adding a polymerization initiator such as azobisisobutyronitrile or benzoyl peroxide. Is the method.

  A characteristic of general bulk radical polymerization is that the polymerization rate is high and a relatively pure polymer is produced in bulk. In general bulk radical polymerization, regardless of the production scale, it is difficult to remove the polymerization heat (difficult to remove heat) and local heating (local runaway reaction) is difficult to control the polymerization temperature. .

In the method of manufacturing the acrylic copolymer of the present invention, the inert gas substituted the gas phase oxygen concentration in the manufacturing vessel, preferably, 0.0vol% ≦ gas phase oxygen concentration ≦ 8.0vol%, more preferably Is preferably carried out in an atmosphere of 0.05 vol% ≦ gas phase oxygen concentration ≦ 8.0 vol%, more preferably 0.2 vol% ≦ gas phase oxygen concentration ≦ 6.0 vol%. In the method for producing an acrylic copolymer of the present invention, if the gas phase oxygen concentration is 0.02 vol% ≦ gas phase oxygen concentration ≦ 8.0 vol%, the acrylic monomer causes a polymerization reaction in the gas phase portion. The acrylic copolymer can be produced safely and efficiently.

  In the method for producing an acrylic copolymer of the present invention, the oxygen concentration in the polymerization system was measured using “Digital Oxygen Concentrator XO-326ALB” (oxygen concentration measuring instrument of New Cosmos Electric Co., Ltd.). Moreover, in the manufacturing method of the acrylic copolymer of this invention, the inert gas used by this invention can be arbitrarily selected from what is marketed, such as nitrogen gas and helium gas.

  Furthermore, in the method for producing an acrylic copolymer of the present invention, when the gas phase oxygen concentration is controlled by blowing an inert gas or a mixed gas of inert gas / air, the inert gas or the inert gas is used. It is recommended that the / air mixture gas be at a temperature sufficiently low that radical polymerization of the acrylic monomer is not initiated. In the method for producing an acrylic copolymer of the present invention, from this point of view, the temperature of the inert gas or the mixed gas of the inert gas / air is preferably as low as possible, but is preferably 40 ° C. or less, more preferably 30 It is recommended that the temperature is not higher than ° C, more preferably not higher than 25 ° C. In the method for producing an acrylic copolymer of the present invention, if the temperature of the inert gas or the inert gas / air mixed gas is preferably 40 ° C. or less, the acrylic copolymer present in the gas phase part of the acrylic copolymer production vessel is used. The vapor of the monomer is cooled and the acrylic monomer tends to be less likely to cause radical polymerization in the gas phase part of the acrylic copolymer production container, vessel wall, condenser, etc., making the acrylic copolymer production safer The tendency to be able to be seen is seen.

  An example of the method for producing the acrylic copolymer of the present invention can be illustrated as follows.

  A polymerization apparatus equipped with a stirrer, an inert gas inlet, a condenser, and an acrylic monomer dropping apparatus is charged with a predetermined amount of acrylic monomer, for example, n-butyl acrylate at 25 ° C., α-methylstyrene dimer. An organic azo polymerization initiator having a predetermined amount and a melting point of 105 ° C. or less, for example, 2,2′-azobis (2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 45 to 70 C., molecular weight 248.4, 10 hour half-life temperature 51.degree. C.) (0.02 to 1.00 mol when the amount of [alpha] -methylstyrene dimer used is 1.0 mol), and stirred. Then, nitrogen gas bubbling at a temperature adjusted to 25 ° C. is performed for 30 minutes. Stop nitrogen gas bubbling and switch to blowing.

  The temperature rise is started and the temperature is raised to 95 ° C. in 90 minutes. Thereafter, the polymerization is continued until the polymerization rate reaches 98% or more to produce an acrylic copolymer.

  The details of the present invention will be described in the following examples. In the following examples, the evaluation method, measurement method, and the like were as follows.

1) Oxygen concentration (vol%)
The measurement was performed using a digital oximeter XO-326ALB (a measuring device manufactured by Shin Cosmos Electric Co., Ltd.).

2) Number average molecular weight (Mn), weight average molecular weight (Mw)
Gel permeation chromatography (GPC) “HLC-8220GPC” (test equipment of Tosoh Corporation) was used, and measurement was performed using tetrahydrofuran as a carrier and polystyrene as a molecular weight standard. The molecular weight distribution was calculated by Mw / Mn.

3) Polymerization rate (%)
The heating residue (%) was measured according to JIS K 5407: 1997, and this was defined as the polymerization rate (%). However, the measurement temperature was 140 ° C. and the measurement time was 60 minutes.

4) Acid value (mgKOH)
Measured according to JIS K 5407: 1997.

Example 1
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , Α-methylstyrene dimer 23.8 g (0.1008 mol), 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene 0.40 mol) was added when the dimer was 1.0 mol, and the temperature of the acrylic monomer mixture was adjusted to 30 ° C, and then raised to 95 ° C in 120 minutes.

  Thereafter, the polymerization was continued until the polymerization rate reached 98% or more (about 5 hours) to produce an acrylic copolymer A-1.

  The acrylic copolymer A-1 had a polymerization rate of 99.8%, a number average molecular weight of 45300, a weight average molecular weight of 82400, and a molecular weight distribution of 1.82.

  During the production of the acrylic copolymer A-1, no abnormal polymerization reaction, rapid exotherm, etc. were observed. Acrylic copolymer A-1 could be produced safely and without problems.

Example 2
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , 47.5 g (0.201 mol) of α-methylstyrene dimer, 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene When the dimer was adjusted to 1.0 mol, 0.20 mol) was charged, and the temperature of the acrylic monomer mixture was adjusted to 30 ° C., and then the temperature was raised to 95 ° C. over 30 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 7 hours) to produce an acrylic copolymer A-2.

  The acrylic copolymer A-2 had a polymerization rate of 98.8%, a number average molecular weight of 23200, a weight average molecular weight of 47300, and a molecular weight distribution of 2.04.

  During the production of the acrylic copolymer A-2, the acrylic copolymer A-2, in which no abnormal polymerization reaction, rapid exotherm, etc. were observed, could be produced safely and without problems.

Example 3
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , Α-methylstyrene dimer 23.7 g (0.1006 mol), 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene 0.40 mol) was added when the dimer was 1.0 mol, and the temperature of the acrylic monomer mixture was adjusted to 30 ° C, and then raised to 95 ° C in 600 minutes. After completion of the temperature increase, it was confirmed that the polymerization rate was already 98% or more, and an acrylic copolymer A-3 was produced.

  The acrylic copolymer A-3 had a polymerization rate of 99.8%, a number average molecular weight of 45500, a weight average molecular weight of 78600, and a molecular weight distribution of 1.73.

  During the production of the acrylic copolymer A-3, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-3 could be produced safely and without problems.

Example 4
While blowing nitrogen gas adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 710 g of n-butyl acrylate and 200 g of cyclohexyl acrylate , 40 g of acrylic acid, 50 g of “Aron Macromer AA-6” (polymethyl methacrylate macromonomer manufactured by Toagosei Co., Ltd., weight average molecular weight 6000), 30.7 g of α-methylstyrene dimer (0.1302 mol), dimethyl 2,2 ′ -Azobis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 22-28 ° C., molecular weight: 230.3, 10 hour half-life temperature: 66 ° C.) 10 g (0.0434 mol) ( 1% by weight of the total amount of the acrylic monomer, and 0.33 mol when α-methylstyrene dimer is 1.0 mol), After adjusting the temperature of the acrylic monomer mixture to 30 ° C., the temperature was raised to 95 ° C. in 120 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 7 hours) to produce an acrylic copolymer A-4.

  The acrylic copolymer A-4 had a polymerization rate of 98.5%, a number average molecular weight of 34200, a weight average molecular weight of 81500, a molecular weight distribution of 2.38, and an acid value of 31.2 mgKOH.

  During the production of the acrylic copolymer A-4, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-4 could be produced safely and without problems.

Example 5
While blowing nitrogen gas adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 470 g of n-butyl acrylate and 2-methacrylic acid 2- 200 g of ethylhexyl, 100 g of glycidyl methacrylate, 200 g of styrene, 30 g of 2-hydroxyethyl methacrylate, 51.2 g (0.217 mol) of α-methylstyrene dimer, dimethyl 2,2′-azobis (2-methylpropionate) ( “V-601” manufactured by Wako Pure Chemical Industries, Ltd. (melting point: 22 to 28 ° C., molecular weight: 230.3, 10 hour half-life temperature: 66 ° C.) 10 g (0.0434 mol) (1% by weight of the total amount of acrylic monomers, α -When the methylstyrene dimer is 1.0 mol, 0.20 mol) is charged, and the temperature of the acrylic monomer mixture is 30 ° C. Then, the temperature was raised to 95 ° C. in 120 minutes.

  Thereafter, the polymerization was continued until the polymerization rate reached 98% or more (about 8 hours) to produce an acrylic copolymer A-5.

  The acrylic copolymer A-5 had a polymerization rate of 99.8%, a number average molecular weight of 23200, a weight average molecular weight of 42900, and a molecular weight distribution of 1.85.

  During the production of the acrylic copolymer A-5, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-5 could be produced safely and without problems.

Example 6
While blowing nitrogen gas adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 710 g of n-butyl acrylate and 200 g of cyclohexyl acrylate 40 g of acrylic acid, 50 g of “Aron Macromer AA-6” (polymethyl methacrylate macromonomer manufactured by Toagosei Co., Ltd., weight average molecular weight 6000), 29.0 g of α-methylstyrene dimer (0.1227 mol), 1,1′- Azobis (cyclohexane-1-carbonitrile) (“V-40” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 113-115 ° C., molecular weight 244.3, 10 hour half-life temperature 88 ° C.) 10 g (0.0409 mol) (acrylic) 1% by weight of the total amount of monomers, and 0.33 mol when α-methylstyrene dimer is 1.0 mol) After adjusting the temperature of the acrylic monomer mixture to 30 ° C., the temperature was raised to 120 ° C. in 300 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 5 hours) to produce an acrylic copolymer A-6.

  The acrylic copolymer A-6 had a polymerization rate of 99.2%, a number average molecular weight of 32800, a weight average molecular weight of 93200, a molecular weight distribution of 2.84, and an acid value of 31.2 mgKOH.

  During the production of the acrylic copolymer A-6, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-6 could be produced safely and without problems.

Example 7
While blowing nitrogen gas adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 710 g of n-butyl acrylate and 200 g of cyclohexyl acrylate , 40 g of acrylic acid, 50 g of “Aron Macromer AA-6” (polymethyl methacrylate macromonomer manufactured by Toagosei Co., Ltd., weight average molecular weight 6000), 28.7 g (0.1216 mol) of α-methylstyrene dimer, 2,2′- Azobis (4-methoxy-2,4-dimethylvaleronitrile) (“V-70” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.) 25 g (0. (0811 mol) (2.5% by weight of the total amount of acrylic monomers, and 0.67 mol when α-methylstyrene dimer is 1.0 mol) ) Were charged, after adjusting the temperature of the acrylic monomer mixture to 30 ° C., the temperature was raised to 80 ° C. in 300 minutes.

  Thereafter, the polymerization was continued until the polymerization rate reached 98% or more (about 8 hours) to produce an acrylic copolymer A-7.

  The acrylic copolymer A-7 had a polymerization rate of 99.6%, a number average molecular weight of 43200, a weight average molecular weight of 62600, a molecular weight distribution of 1.45, and an acid value of 31.2 mgKOH.

  During the production of the acrylic copolymer A-7, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-7 could be produced safely and without problems.

Example 8
While blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirrer, and an acrylic monomer charging port, n-butyl acrylate 758, ethyl acrylate 200 g , 12 g of acrylic acid, 30 g of 2-hydroxyethyl methacrylate, 2.3 g (0.00975 mol) of α-methylstyrene dimer, 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis ( 2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 2 g (0.00805 mol) (acrylic unit 0.23% by weight of the total amount of the monomer, and 0.83 mol when α-methylstyrene dimer is 1.0 mol), the temperature of the acrylic monomer mixture is adjusted. After adjusting to 0 ° C., the temperature was raised to 95 ° C. for 120 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 5 hours) to produce an acrylic copolymer A-8.

  The acrylic copolymer A-8 had a polymerization rate of 99.2%, a number average molecular weight 63800, a weight average molecular weight 92800, a molecular weight distribution 1.45, and an acid value of 9.4 mgKOH.

  During the production of the acrylic copolymer A-8, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-8 could be produced safely and without problems.

Example 9
While blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirrer, and an acrylic monomer charging port, n-butyl acrylate 758, ethyl acrylate 200 g , 12 g of acrylic acid, 30 g of 2-hydroxyethyl methacrylate, 9.5 g (0.0403 mol) of α-methylstyrene dimer, 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis ( 2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45-70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 5 g (0.0201 mol) (acrylic unit 0.20% by weight of the total amount of the monomer and 0.50 mol when α-methylstyrene dimer is 1.0 mol), and the temperature of the acrylic monomer mixture is 30. After adjusting, the temperature was raised to 95 ° C. for 120 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 5 hours) to produce an acrylic copolymer A-9.

  The acrylic copolymer A-9 had a polymerization rate of 99.3%, a number average molecular weight of 40200, a weight average molecular weight of 60200, a molecular weight distribution of 1.50, and an acid value of 9.4 mgKOH.

  During the production of the acrylic copolymer A-9, abnormal polymerization reaction, rapid heat generation, etc. were not observed. Acrylic copolymer A-9 could be produced safely and without problems.

Example 10
While blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirrer, and an acrylic monomer charging port, n-butyl acrylate 758, ethyl acrylate 200 g , 12 g of acrylic acid, 30 g of 2-hydroxyethyl methacrylate, 95.0 g (0.403 mol) of α-methylstyrene dimer, 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis ( 2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45-70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 20 g (0.0805 mol) (acrylic unit 2% by weight of the total amount of the monomer, 0.20 mol when α-methylstyrene dimer is 1.0 mol), and the temperature of the acrylic monomer mixture is 30 ° C. After adjusting, the temperature was raised to 95 ° C. for 120 minutes.

  Thereafter, polymerization was continued until the polymerization rate reached 98% or more (about 5 hours) to produce an acrylic copolymer A-10.

  The acrylic copolymer A-10 had a polymerization rate of 99.8%, a number average molecular weight of 14300, a weight average molecular weight of 21100, a molecular weight distribution of 1.48, and an acid value of 9.4 mgKOH.

  During the production of the acrylic copolymer A-10, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-10 could be produced safely and without problems.

  Table 1 summarizes the acrylic copolymer compositions, production methods, and characteristic values of Examples 1 to 10.

  In Table 1, “Aron Macromer AA-6” is a polymethyl methacrylate macromonomer, a product of Toagosei Co., Ltd., “V-40” is 1,1′-azobis (cyclohexane-1-carbonitrile) ( “V-40” manufactured by Wako Pure Chemical Industries, Ltd. (melting point: 113 to 115 ° C., molecular weight: 244.3, 10 hour half-life temperature: 88 ° C.), “V-65 is 2,2′-azobis (2,4- Dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45-70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.), “V-70” is 2,2′- Azobis (4-methoxy-2,4-dimethylvaleronitrile) (“V-70” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 50 to 96 ° C., molecular weight: 308.4, 10 hour half-life temperature: 30 ° C.) -601 "is dimethyl-2,2'-a Bis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point 22-28 ° C., molecular weight 230.3, 10-hour half-life temperature 66 ° C.), “R / I” is The number of moles of the organic azo polymerization initiator when the number of moles of α-methylstyrene dimer is 1.0 mole is shown.

Comparative Example 1
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , Α-methylstyrene dimer 9.0 g (0.0381 mol), 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene 1.05 mol when the dimer was 1.0 mol), the temperature of the acrylic monomer mixture was adjusted to 30 ° C., and then the temperature was raised to 95 ° C. over 120 minutes to attempt polymerization. A runaway reaction occurred during the temperature rise, and temperature control became impossible.

Comparative Example 2
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , Α-methylstyrene dimer 23.8 g (0.1008 mol), 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene 0.40 mol) when the dimer was 1.0 mol), the temperature of the acrylic monomer mixture was adjusted to 30 ° C., and then the temperature was raised to 95 ° C. over 25 minutes to attempt polymerization. A runaway reaction occurred during the temperature rise, and temperature control became impossible.

Comparative Example 3
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , 523 g (2.22 mol) of α-methylstyrene dimer, 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd.) “V-65”) (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene dimer 0.018 mol) was added, and the temperature of the acrylic monomer mixture was adjusted to 30 ° C., and then the temperature was raised to 95 ° C. over 120 minutes to attempt polymerization. Polymerization was carried out at 95 ° C. for 20 hours, but the polymerization rate increased only to 48.6%.

Comparative Example 4
N-butyl acrylate 800 and ethyl acrylate 200 g while blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port , Α-methylstyrene dimer 23.8 g (0.1008 mol), 2,2′-azobis (2,4-dimethylvaleronitrile) 2,2′-azobis (2,4-dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd.) “V-65” manufactured by Kogyo Co., Ltd. (melting point: 45 to 70 ° C., molecular weight: 248.4, 10 hour half-life temperature: 51 ° C.) 10 g (0.0403 mol) (1% by weight of the total amount of acrylic monomers, α-methylstyrene 0.40 mol when the dimer is 1.0 mol), the temperature of the acrylic monomer mixture is adjusted to 30 ° C., and then the temperature is raised to 95 ° C. in 700 minutes to attempt polymerization. .

  Although it was possible to produce an acrylic copolymer, the viscosity became high during the temperature increase, and stirring was insufficient, so that accurate temperature control was difficult. Moreover, 10 hours or more were required only for temperature rise, and production efficiency was bad.

  Table 2 summarizes the acrylic copolymer compositions, production methods, and characteristic values of Comparative Examples 1 to 4.

  In Table 1, “V-65” is 2,2′-azobis (2,4-dimethylvaleronitrile) (“V-65” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 45 to 70 ° C., molecular weight: 248.4, “R / I” indicates the number of moles of the organic azo polymerization initiator when the number of moles of α-methylstyrene dimer is 1.0 mole.

Example 11
While blowing nitrogen gas adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 530 g of n-butyl acrylate and 400 g of cyclohexyl acrylate 40 g of acrylic acid, 30 g of “Aron Macromer AA-6” (polymethyl methacrylate macromonomer manufactured by Toagosei Co., Ltd., weight average molecular weight 6000), 51.2 g (0.217 mol) of α-methylstyrene dimer, dimethyl 2,2 ′ -Azobis (2-methylpropionate) (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) (melting point: 22-28 ° C., molecular weight: 230.3, 10 hour half-life temperature: 66 ° C.) 10 g (0.0434 mol) ( 1% by weight of the total amount of acrylic monomers and 0.20 mol) when α-methylstyrene dimer is 1.0 mol, After adjusting the temperature of the kryl monomer mixture to 30 ° C., the temperature was raised to 95 ° C. in 120 minutes.

  Thereafter, the polymerization was continued until the polymerization rate reached 98% or more (about 8 hours) to produce an acrylic copolymer A-11.

  The acrylic copolymer A-11 had a polymerization rate of 99.3%, a number average molecular weight of 16,200, a weight average molecular weight of 42000, a molecular weight distribution of 2.59, and an acid value of 31.2 mgKOH.

  During the production of the acrylic copolymer A-11, abnormal polymerization reaction, rapid exotherm, etc. were not observed. Acrylic copolymer A-11 could be produced safely and without problems.

  While blowing nitrogen gas whose temperature was adjusted to 20 ° C. into a 2 L four-necked flask having a nitrogen gas inlet tube, a reflux condenser, a stirring device, and an acrylic monomer charging port, 500 g of acrylic copolymer A-11, acrylic 125 g of acid n-butyl, 250 g of n-butyl methacrylate, 25 g of styrene, 50 g of glycidyl methacrylate, 50 g of 2-hydroxyethyl methacrylate, 2,2′-azobis (2-methylpropionate) (manufactured by Wako Pure Chemical Industries, Ltd.) V-601 ") (melting point 22-28 ° C, molecular weight 230.3, 10 hour half-life temperature 66 ° C) 5 g (0.0217 mol) (1% by weight of the total amount of acrylic monomer) After adjusting the temperature of the mixture to 30 ° C., the temperature was raised to 95 ° C. over 180 minutes.

  Thereafter, polymerization is performed until the polymerization rate reaches 98% or more (about 8 hours), and acrylic copolymer A-11 having a carboxyl group in the molecular side chain and an acrylic copolymer having an epoxy group in the molecular side chain. A block copolymer consisting of

  The block copolymer had a polymerization rate of 99.2%, a number average molecular weight of 35400, a weight average molecular weight of 77800, a molecular weight distribution of 2.20, and an acid value of 15.6 mgKOH.

Claims (4)

Shown by the following structural formula

(Here, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 1 to 12 carbon atoms.)
Acrylic monomer including acrylic monomer, represented by the following structural formula

an acrylic monomer mixture containing α-methylstyrene dimer and 0.02 to 1.00 mol of an organic azo polymerization initiator with respect to 1.0 mol of α-methylstyrene dimer was charged at 5 to 40 ° C .; A process for producing an acrylic copolymer, wherein the temperature is raised in 30 to 600 minutes to the radical polymerization temperature of the acrylic monomer , and then bulk radical polymerization is carried out at 80 to 100 ° C. The method for producing an acrylic copolymer according to claim 1, wherein the organic azo polymerization initiator has a melting point of 20 to 105 ° C. The method for producing an acrylic copolymer according to claim 1 or 2 , wherein the organic azo polymerization initiator has a 10-hour half-life temperature of 20 to 100 ° C. The method for producing an acrylic copolymer according to any one of claims 1 to 3, wherein the organic azo polymerization initiator has a molecular weight of 190 to 320.