Method for producing polymer, composition for radical polymerization and radical polymerization control agent

Abstract

A method for manufacturing a polymer includes a polymerization step in which a monomer (Y) undergoes controlled free radical polymerization in the presence of an organic compound (A) as shown in formula (I) and a free radical generator (B) to obtain a polymer; wherein the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20. According to this manufacturing method, high molecular weight and highly safe polymers can be synthesized while precisely controlling molecular arrangement and terminal structure. Furthermore, this manufacturing method is low in toxicity, environmentally friendly, and low in cost. [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group as shown in formula (II) or (III) below; R1 and R2 may also be linked to form a ring.] [In formula (II), R3 is a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group; * indicates a bonding bond.] [In equation (III), R3 is synonymous with equation (II) above, and * denotes a bonding bond.]

Description

Technical Field

[0001] This invention relates to a method for manufacturing a polymer, comprising a polymerization step of polymerizing polymerizable monomers through controlled radical polymerization. Furthermore, it relates to a composition for radical polymerization and a radical polymerization control agent used in such a manufacturing method. Prior Technology

[0002] Polyvinyl alcohol (PVA) resin is a crystalline, water-soluble polymer material. Utilizing its excellent water solubility and film-forming properties (strength, oil resistance, film-forming ability, oxygen barrier properties, etc.), it is widely used as an emulsifier, suspending agent, surfactant, fiber processing agent, various adhesives, paper processing agents, bonding agents, and films. To date, PVAs with varying degrees of saponification and polymerization have been used according to their applications. Furthermore, various modified PVAs have been proposed, which impart special functions by introducing functional groups into PVA.

[0003] Industrially, polyvinyl alcohol is produced by saponifying polyvinyl acetate, which is obtained through free radical polymerization of vinyl acetate. The free radical polymerization of vinyl acetate involves various side reactions such as chain transfer and rebonding termination reactions. Therefore, it is generally considered difficult to precisely control the molecular arrangement and terminal structure of the obtained polyvinyl acetate (and polyvinyl alcohol).

[0004] In recent years, advancements in living radical polymerization (LRP) technology have led to the proposal of several methods for controlling the free radical polymerization of vinyl acetate. For example, a method has been proposed to obtain polyvinyl acetate with precisely controlled structures by conducting LRP in the presence of a free radical polymerization initiator and a specific control agent. In this type of polymerization, the growth radical ends of the polyvinyl acetate molecular chains form dormant species through covalent bonding with the control agent, and polymerization occurs while an equilibrium is maintained between these dormant species and the free radical species generated from their dissociation. This type of polymerization is called controlled radical polymerization.

[0005] However, controlled radical polymerization methods to date have struggled to yield high molecular weight polyvinyl acetate (PVC). This is believed to be because the free radicals generated at the ends of head-to-head bonds (bonds where the acetyl groups of vinyl acetate are adjacent to each other) that form with a certain probability during polymerization are thermally unstable. Therefore, the equilibrium shifts significantly towards the dormant species side, causing the polymerization reaction to cease. On the other hand, while increasing the polymerization temperature to promote the thermal dissociation of dormant species will allow the reaction to proceed, the controllability deteriorates. Therefore, obtaining high molecular weight PVC systems while maintaining controllability is extremely difficult.

[0006] One proposed approach to this problem involves synthesizing high-molecular-weight polyvinyl acetate with controlled free radical polymerization using an organocobalt complex as a control agent. In this polymerization reaction, the growth radical ends of the polyvinyl acetate molecular chain are covalently bonded to the cobalt atoms of the organocobalt complex to form dormant species. Polymerization proceeds while an equilibrium is established between these dormant species and the free radical species generated from their dissociation. For example, Non-Patent Literature 1 reports an example of synthesizing polyvinyl acetate with a number average molecular weight (Mn) of 99,000 and a molecular weight distribution (Mw / Mn) of 1.33 by polymerizing it in the presence of cobalt(II) acetone.

[0007] Patent document 1 describes that polyvinyl alcohol obtained by controlled free radical polymerization has the problem of obvious coloration. In contrast, for polyvinyl acetate solution obtained by controlled free radical polymerization using an organocobalt complex as a control agent, after contacting it with an aqueous solution containing a water-soluble ligand to extract and remove the cobalt complex, followed by saponification, polyvinyl alcohol with reduced coloration can be obtained.

[0008] However, this polymerization method using metal complexes has the following drawbacks: Completely removing used complexes from the obtained polymer is not easy. Many transition metals are highly toxic, and the toxicity of residual transition metals in the molded product of the obtained polymer could become an environmental problem, making it difficult to use molded products containing transition metals in food packaging materials, biological and medical materials, etc. Furthermore, the toxicity of unwanted complexes and those removed from the polymer after the reaction could also become an environmental problem. In addition, the removal of complexes requires a large amount of extraction liquid, complicating the process and increasing costs. Moreover, metal complexes are typically expensive and require complex synthesis.

[0009] A living radical polymerization method that does not require the use of metal complexes is also known. Methods using, for example, nitroxyl, iodine, or dithioester compounds are known. However, these methods have the following drawbacks: a specific protecting group must be introduced into the polymer growth chain, and this protecting group is often very valent. There is also the drawback of requiring polymerization at high temperatures (e.g., above 110°C). Furthermore, the polymerization of vinyl esters is not sufficiently controlled, making it difficult to obtain high molecular weight products. The resulting polymer may also be discolored or have an odor, easily developing undesirable properties. In addition, completely removing the used compounds from the finished product is not easy, and there is a risk of health and environmental problems due to residual organohalogen or organosulfur compounds.

[0010] However, cinnamic acid and its derivatives are widely found in nature and are generally used industrially as food additives and flavorings. It is known that although cinnamic acids possess unsaturated double bonds, they are not easily homopolymerized. Under conditions limited to copolymerization with fumarate diesters, they undergo free radical polymerization of cinnamic acid monomers (Non-Patent Document 2, Patent Document 2). Furthermore, it is known that by adding cinnamic acid to a post-polymerized polyvinyl acetate solution, polyvinyl alcohol with suppressed fish-eye and odor generation during molding can be obtained (Patent Document 3). However, examples of cinnamic acid being used as a control agent for controlled free radical polymerization are not yet known, and academically, such a function is not conceivable. [Previous Technical Documents] [Patent Literature]

[0011] Patent Document 1: WO2017-170974 Patent Document 2: Japanese Patent Application Publication No. 2014-129503 Patent Document 3: Japanese Patent Application Publication No. 2002-053728 [Non-patent literature]

[0012] Non-Patent Literature 1: Highly Efficient Cobalt-Mediated Radical Polymerization of Vinyl Acetate, Angewandte Chemie International Edition, 2005, vol.44, pp.1101-1104 Non-Patent Literature 2: Free Radical Copolymerization of Alkyl Cinnamate and Alkyl Atoranoate, Journal of Industrial Chemistry, Vol. 70, No. 11, 1967, pp. 1941-1944 Summary of the Invention

[0013] [The problem the invention aims to solve]

[0014] This invention addresses the aforementioned problems by providing a method for manufacturing a polymer that is low in toxicity, environmentally friendly, exhibits high polymerization control, yields high molecular weight compounds, and is cost-effective. Furthermore, the invention aims to provide a free radical polymerization composition and a free radical polymerization control agent suitable for use in this manufacturing method. [Methods used to solve problems]

[0015] The above-mentioned problem is solved by providing a method for manufacturing a polymer, wherein the method includes a polymerization step of carrying out controlled free radical polymerization of monomer (Y) in the presence of an organic compound (A) as shown in formula (I) and a free radical generator (B) to obtain a polymer, and the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20.

[0016] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0017] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0018] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0019] In this case, R1 is preferably aryl. It is also preferred that the organic compound (A) is of type E. It is also preferred that the organic compound (A) is represented by formula (IV) below.

[0020] [In formula (IV), R3 is synonymous with formula (II) above, and R4 is a hydrogen atom, alkyl group, alkoxy group, or hydroxyl group.]

[0021] In this case, R4 is preferably a hydrogen atom. R3 is preferably a methoxy or hydroxyl group. A molar ratio (Y / A) of 300 to 30,000 for the monomer (Y) to the organic compound (A) is also preferred.

[0022] In the aforementioned manufacturing method, the monomer (Y) preferably comprises an olefin, ethylene ester, acrylic acid, acrylate, acrylamide monomer, styrene monomer, N-vinylamide monomer, or dicarboxylic acid monomer. In this case, the aforementioned manufacturing method is more preferably comprising: a polymerization step and a saponification step; wherein the polymerization step involves controlled free radical polymerization of ethylene ester in the presence of an organic compound (A) and a free radical generator (B) to obtain an ethylene ester polymer; and the saponification step involves saponifying the obtained ethylene ester polymer to obtain an vinyl alcohol polymer.

[0023] The aforementioned manufacturing method is further preferably comprising: a polymerization step and a saponification step; wherein, the polymerization step involves sequentially performing controlled free radical polymerization of ethylene ester and controlled free radical polymerization of ethylene ester and monomers other than ethylene ester in the presence of an organic compound (A) and a free radical generator (B) to obtain an ethylene ester-based block copolymer; the saponification step involves saponifying the obtained ethylene ester-based block copolymer to obtain an ethylene alcohol-based block copolymer.

[0024] The above-mentioned problem can also be solved by providing a composition for free radical polymerization; the composition for free radical polymerization includes: an organic compound (A) as shown in formula (I) below and a free radical generator (B), and the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20.

[0025] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0026] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0027] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0028] At this point, the composition for free radical polymerization is preferably further comprising monomer (Y), and the molar ratio (Y / a) of monomer (Y) relative to organic compound (a) is 300 to 30000.

[0029] The aforementioned problem can also be solved by providing a free radical polymerization control agent comprising an organic compound (A) as shown in formula (I) below.

[0030] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0031] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0032] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0033] Polymers having the end structures shown in formula (V) or (VI) below are suitable embodiments of the present invention.

[0034] [In formula (V), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring. * indicates a bonding bond.]

[0035] [In equation (VI), R1 and R2 are synonymous with those in equation (V) above, and * denotes a bonding bond.]

[0036] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0037] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.] [Effects of the Invention]

[0038] The organic compound (A) used in the manufacturing method of this invention is highly safe, has high polymerization controllability, and is inexpensive. Therefore, according to this manufacturing method, high molecular weight and highly safe polymers can be synthesized while precisely controlling molecular arrangement and terminal structure. Furthermore, this manufacturing method is low in toxicity and environmentally friendly, and does not require a step to remove organic compound (A), thus offering low cost. The free radical polymerization composition and free radical polymerization control agent of this invention can be suitably used in the manufacturing method of such polymers. Simple Explanation of the Diagram

[0039] Figure 1 is a graph obtained by plotting the conversion rate of vinyl acetate by the number average molecular weight (Mn) in Example 1. Implementation

[0040] [The form in which the invention is carried out]

[0041] The present invention relates to a method for manufacturing a polymer, comprising a polymerization step of carrying out controlled free radical polymerization of monomer (Y) in the presence of an organic compound (A) as shown in formula (I) and a free radical generator (B) to obtain a polymer, wherein the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20.

[0042]

[0043] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0044] In the polymerization step, the monomer (Y) undergoes controlled free radical polymerization in the presence of the organic compound (A) shown in formula (I) and the free radical generator (B) to obtain the polymer. The controlled free radical polymerization employed in the manufacturing method of this invention refers to a polymerization reaction that takes place in an equilibrium state between the growing free radical ends (active species) and the covalently bonded species (dormant species) already bonded to the control agent. In the manufacturing method of this invention, the organic compound (A) shown in formula (I) functions as the control agent. By using the organic compound (A), the free radical polymerization is highly controlled, thus enabling the precise control of molecular arrangement and terminal structure while obtaining high molecular weight polymers. Furthermore, since the organic compound (A) is inexpensive and industrially used as a food additive and flavoring, and is highly safe, there is no need for a step to remove the organic compound (A). Therefore, the manufacturing method of this invention is environmentally friendly and cost-effective.

[0045] In the above formula (I), R1 is an alkenyl or aryl group, preferably an aryl group.

[0046] The aforementioned aryl group preferably has 6 to 15 carbon atoms. More preferably, it has 13 or fewer carbon atoms, further preferably 12 or fewer, and most preferably 10 or fewer. Examples of the aforementioned aryl group include: phenyl, biphenyl, naphthyl, anthryl, indenyl, fluorenyl, phenanthryl, indacenyl, phenalenyl, azulenyl, pyridyl, furanyl, etc., with phenyl being the most preferred. Without impairing the scope of the invention, the aforementioned aryl group may also have substituents. Examples of such substituents include: alkoxy, amino (including monoalkylamino and dialkylamino), carboxyl, ester, silicone, sulfanyl, cyano, nitro, sulfonyl, formyl, aryl, halogen, hydroxyl, ether, and alkenyl, with alkyl and alkoxy being preferred. Examples of alkyl and alkoxy groups include those used as R3 in formula (II). From an environmental and safety perspective, the aforementioned aryl group is preferably unsubstituented.

[0047] The alkenyl group preferably has 2 to 10 carbon atoms. More preferably, it has 8 or fewer carbon atoms. On the other hand, it is more preferably 4 or more carbon atoms. The alkenyl group can be a straight-chain or branched alkenyl group, or it can be a cyclic alkenyl group. Examples of alkenyl groups include: straight-chain or branched alkenyl groups such as vinyl, allyl, methyl vinyl, propenyl, butenyl, pentenyl, and hexenyl; and cyclic alkenyl groups such as cyclopropenyl, cyclobutenyl, cyclopentenyl, and cyclohexenyl. Among these, cyclic alkenyl groups are preferred, and cyclohexenyl groups are more preferred. Without affecting the scope of the invention, the alkenyl group may also have substituents. Examples of such substituents include those described above that are substituents for the aforementioned aryl groups.

[0048] In the above formula (I), R2 is a basis shown in formula (II) or (III) below, preferably a basis shown in formula (II) below.

[0049] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0050] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0051] In formula (II) above, R 3 refers to hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino (including: monoalkylamino, dialkylamino), nitro, cyano, acetyl, trifluoromethyl or hydroxyl, preferably hydrogen atom, alkyl, aryl, alkoxy or hydroxyl, more preferably alkyl, alkoxy or hydroxyl, and most preferably alkoxy or hydroxyl.

[0052] The aforementioned alkyl group preferably has 1 to 10 carbon atoms. More preferably, it has 8 or fewer carbon atoms, further preferably 6 or fewer, even more preferably 4 or fewer, and most preferably 2 or fewer. The aforementioned alkyl group can be a straight-chain or branched alkyl group, or it can be a cyclic cycloalkyl group. Examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, tertiary butyl, n-pentyl, isopentyl, neopentyl, tertiary pentyl, n-hexyl, isohexyl, 2-ethylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, etc., straight-chain or branched alkyl groups; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, etc. Among these, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, tertiary butyl, and more preferably methyl. Without impairing the scope of the invention, the aforementioned alkyl group may also have substituents. Examples of such substituents include those that can be used as substituents for the aforementioned aryl group in R1. From an environmental and safety perspective, it is preferable that the aforementioned alkyl group is unsubstituented.

[0053] The aforementioned aryl group preferably has 6 to 15 carbon atoms. More preferably, it has 13 or less carbon atoms, even more preferably 12 or less carbon atoms, and most preferably 10 or less carbon atoms. Regarding the aforementioned aryl group, examples include those that can be used as R1.

[0054] The aforementioned alkoxy group preferably has 1 to 10 carbon atoms. More preferably, it has 8 or fewer carbon atoms, further preferably 6 or fewer, even more preferably 4 or fewer, and most preferably 1. Examples of the aforementioned alkoxy groups include: methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, secondary butoxy, tertiary butoxy, pentoxy, isopentoxy, neopentoxy, hexoxy, cyclohexoxy, heptoxy, octoxy, nonoxy, decoxy, etc. Among these, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, secondary butoxy, and tertiary butoxy are preferred, and methoxy is even more preferred. Without impairing the scope of the invention, the aforementioned alkoxy group may also have substituents. Examples of such substituents include those that can be used as substituents for the aforementioned aryl group before R1. From the perspective of better environmental impact and safety, the aforementioned alkoxy group preferably does not have substituents.

[0055] The organic compound (A) shown in formula (I) above can be of type E or type Z, but type E is preferred. That is, the controlled free radical polymerization of monomer (Y) is preferably carried out in the presence of type E organic compound (A) and free radical generator (B). In this case, type Z organic compound (A) can also be present as an arbitrary component. Thus, when type Z organic compound (A) is present, the molar ratio of type E to the total of type E and type Z (E / E+Z) is preferably greater than 0.5, more preferably greater than 0.7, and even more preferably greater than 0.8. The molar ratio of free radical generator (B) to the total of type E and type Z (B / E+Z) is preferably within the same range as the molar ratio (B / A) described later. Furthermore, the molar ratio of monomer (Y) to the total of type E and type Z (Y / E+Z) is preferably within the same range as the molar ratio (Y / A) described later.

[0056] The organic compound (A) shown in formula (I) above is preferably the one shown in formula (IV) below.

[0057] [In formula (IV), R3 is synonymous with formula (II) above, and R4 is a hydrogen atom, alkyl group, alkoxy group, or hydroxyl group.]

[0058] In formula (IV) above, R4 is a hydrogen atom, an alkyl group, an alkoxy group, or a hydroxyl group. Preferably, R4 is a hydrogen atom. The bonding position of R4 in a phenyl group is not particularly limited. Examples of alkyl and alkoxy groups that can be used as R4 include those described above that can be used as R3.

[0059] In formula (I) above, R1 and R2 can also be linked together to form a ring. Examples of cyclic organic compounds (A) formed in this way include those shown in formula (VII) below.

[0060]

[0061] Regarding the free radical generator (B) used in the polymerization step, azo-based free radical generators, peroxide-based free radical generators, redox-based free radical generators, etc., which are known to date, can be appropriately selected. Examples of azo-based free radical generators include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylpentanonitrile), and 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile). Examples of peroxide-based free radical generators include percarbonate compounds such as diisopropyl peroxide, di-2-ethylhexyl peroxide, and diethoxyethyl peroxide; perester compounds such as tributyl peroxyneodecanate, α-isopropylphenyl peroxyneodecanate, and tributyl peroxyneodecanate; acetylcyclohexylsulfonylurea peroxide and diisobutyl peroxide; and 2,4,4-trimethylpentyl-2-peroxyphenoxyacetic acid ester. Furthermore, peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide can be combined with the above-mentioned free radical generators to create a free radical generator. In addition, regarding redox free radical generators, examples include those composed of the above-mentioned peroxides combined with reducing agents such as sodium bisulfite, sodium bicarbonate, tartaric acid, L-ascorbic acid, and rongalite.

[0062] Regarding polymerization methods, known methods include bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization. Among these, bulk polymerization, which uses no solvent, and solution polymerization, which uses various organic solvents, are commonly employed. From the perspective of suppressing the reduction of free radical ends caused by chain transfer reactions to the solvent or dispersion medium, bulk polymerization without a solvent or dispersion medium is preferable. On the other hand, solution polymerization is also preferable in terms of adjusting the viscosity of the reaction solution or controlling the polymerization rate. Regarding the organic solvents used in solution polymerization, examples include esters such as methyl acetate and ethyl acetate; aromatic hydrocarbons such as benzene and toluene; lower alcohols such as methanol and ethanol; and carbonates such as dimethyl carbonate and diethyl carbonate. Among these, esters or aromatic hydrocarbons, and dimethyl carbonate, are preferred to prevent chain transfer. Furthermore, when the monomer (Y) contains vinyl acetate, and the polymerization process often involves alkaline treatment in methanol, using methanol as the polymerization solvent is preferable considering the permeability of the process. The amount of solvent used can be determined by taking into account the number average molecular weight of the target polymer and the viscosity of the reaction solution. For example, a mass ratio [solvent / monomer (Y)] in the range of 0.01 to 10 can be selected.

[0063] In the controlled free radical polymerization used in this invention, firstly, free radicals generated by the decomposition of the free radical generator (B) bond with a small number of monomers (Y). The free radicals at the growth ends of the resulting short-chain polymer then bond with organic compound (A), forming a dormant species covalently bonded to the polymer ends by organic compound (A). For a certain period after the reaction begins, only short-chain polymers are generated and converted into dormant species; molecular weight increase does not actually occur. This period is called the induction period. After organic compound (A) is consumed, the growth period begins, during which most molecular chains in the reaction system increase in proportion to the polymerization time. The time required for the polymerization step of monomer (Y), including the induction and growth periods, is typically 0.5 to 30 hours.

[0064] As described above, in the controlled radical polymerization of the present invention, theoretically, one polymer chain is generated from one molecule of the added organic compound (A). Therefore, the amount of organic compound (A) added to the reaction solution is determined by considering the target number average molecular weight and conversion rate. From the perspective of obtaining a high molecular weight polymer, in the polymerization step, the molar ratio (Y / A) of monomer (Y) to organic compound (A) is preferably 300 or more, more preferably 1000 or more, further preferably 2000 or more, even more preferably 4000 or more, and particularly preferably 6000 or more. On the other hand, from the perspective of improving the activity rate of the free radical ends, the molar ratio (Y / A) is preferably 30000 or less, more preferably 25000 or less, and further preferably 20000 or less. When organic compound (A) and monomer (Y) are added in multiple batches, the molar ratio (Y / A) is obtained by using the total amount of each.

[0065] In the polymerization step, the ratio (B / A) of the free radical generator (B) to the organic compound (A) is 0.5 to 20. If the number of moles of the generated free radicals is not more than the number of moles of the organic compound (A), the polymerization reaction proceeds solely through the thermal dissociation of the organic compound (A) from a dormant species, and therefore the polymerization rate becomes extremely low depending on the reaction temperature. Therefore, if we consider that the free radical generator (B) generates two free radicals, then in the polymerization step, both the free radical generator (B) and the organic compound (A) should be added to the reaction solution such that the ratio (B / A) is 0.5 or higher. This is because the amount of active free radicals supplied by the free radical generator generally depends on the efficiency of the free radical generator (initiator efficiency), and in reality, there are free radical generators that are not used to form dormant sites and are thus deactivated. Therefore, the mole ratio (B / A) of (B) to (A) is preferably 0.6 or higher, and more preferably 0.8 or higher. On the other hand, if the molar number of the generated free radicals becomes too large compared to the molar number of the organic compound (A), the proportion of uncontrolled free radical polymerization increases, and the polymerization controllability decreases. The molar ratio (B / A) of (B) relative to (A) is preferably 15 or less, more preferably 10 or less, and even more preferably 5 or less. When the organic compound (A) and the free radical generator (B) are added in multiple portions, the molar ratio (B / A) is obtained using the individual total amounts.

[0066] If the monomer exhibits free radical polymerization properties, the monomers (Y) used in the polymerization step are not particularly limited, but are preferably olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride, vinyl fluoride, vinylidene chloride, and vinylidene fluoride; vinyl formate, vinyl acetate, vinyl trifluoroacetate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, vinyl trimethylacetate, vinyl decanoate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl versatate, and other vinyl esters; and vinyl dicyanide. cyanide); acrylic acid; methacrylic acid; methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tributyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, octadecyl acrylate, and other acrylates; methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, and other methacrylic acids; dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate and their quaternary compounds; acrylamide, N-hydroxymethylacrylamide, N,N-dimethylacrylamide, acrylamide-2-methylpropanesulfonic acid and its sodium salt, and other acrylamide monomers; methacrylamide, N,N-dimethylmethacrylamide, trimethyl[3-(methacryloylamino)propyl]ammonium chloride (trimethyl[3-(methacryloylamino]...) Methacrylamide monomers such as propyl[aminium chloride]; styrene monomers such as styrene, α-methylstyrene, p-styrenesulfonic acid and its sodium and potassium salts; N-vinylpyrrolidone, N-vinylmethacrylamide, N-vinylacetamide, N-vinylcaprolactam, and other N-vinylamide monomers; allyl acetate, allyl chloride, 3,4-diethoxy-1-butene, 2-methylene-1,3-propanediol, 2-methylene-1,3-propanediol diacetate, allyl alcohol, dimethyl allyl alcohol, and other allyl monomers; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile. The monomers include cyanide monomers; alkyl (1-18 carbon) vinyl ethers, hydroxyalkyl vinyl ethers, alkoxyalkyl vinyl ethers, and other vinyl ether monomers; dicarboxylic acid monomers such as maleic acid, monomethyl maleate, dimethyl maleate, maleic anhydride, itconic acid, monomethyl itconic acid, dimethyl itconic acid, and itconic anhydride; more preferably, olefins, vinyl esters, acrylic acid, acrylates, acrylamide monomers, styrene monomers, N-vinylamide monomers, or dicarboxylic acid monomers; further preferably, vinyl esters, styrene, or N-vinylpyrrolidone; particularly preferably, vinyl esters or N-vinylpyrrolidone; and most preferably, vinyl esters. The monomer (Y) may contain one or more of these monomers.Monomer (Y) preferably contains one of these monomers as a principal component. Here, "principal component" refers to the monomer present in the largest quantity among the monomers contained in monomer (Y). The content of the monomer that is the principal component in monomer (Y) is preferably 30 mol% or more, more preferably 50 mol% or more, further preferably 70 mol% or more, and especially preferably 80 mol% or more.

[0067] Regarding the aforementioned vinyl esters, from an economic point of view, vinyl acetate is preferred. Regarding the aforementioned acrylates, from an economic point of view, methyl acrylate is preferred.

[0068] In the manufacturing method of the present invention, a homopolymer can be obtained by using one type of monomer as monomer (Y), or a copolymer can be obtained by using two or more monomers as monomer (Y). The copolymer can be either a random copolymer or a block copolymer. Furthermore, the polymer obtained by the manufacturing method of the present invention can be either branched or linear, but linear is preferred due to the high polymerizability control caused by the organic compound (A).

[0069] In methods that generate dormant species to control the molecular weight increase of polymers, the mixing method of the organic compound (A), free radical generator (B), and monomer (Y) is not particularly limited. Examples include: adding the organic compound (A) and free radical generator (B) to the monomer (Y); mixing the resulting mixture after mixing the organic compound (A) and free radical generator (B) with the monomer (Y); mixing the organic compound (A), free radical generator (B), and monomer (Y) in a single step; and mixing the resulting mixture after mixing the organic compound (A) and monomer (Y) with the free radical generator (B), etc. Furthermore, the organic compound (A), free radical generator (B), and monomer (Y) can also be mixed in parts. Examples include: mixing an organic compound (A) and a free radical generator (B) with a portion of a monomer (Y) to generate a dormant species formed by covalent bonding between the organic compound (A) and the short-chain polymer terminus; and then mixing the dormant species with the remaining portion of the monomer (Y) to increase the molecular weight. Alternatively, the dormant species can be isolated and used as a macromolecular initiator, and then mixed with the remaining portion of the monomer (Y) to increase the molecular weight.

[0070] The polymerization temperature is preferably between 0 and 80°C. When the polymerization temperature is below 0°C, the polymerization rate becomes insufficient, which may reduce productivity. From this perspective, the polymerization temperature is preferably above 10°C, and more preferably above 20°C. On the other hand, if the polymerization temperature exceeds 80°C, the controllability of free radical polymerization may decrease. From this perspective, the polymerization temperature is preferably below 70°C, and more preferably below 65°C.

[0071] From the perspective of further improving polymerization control, when the monomer (Y) conversion rate is 5.0%, the ratio of the polymer's number average molecular weight (Mn) (measured value) to the theoretical number average molecular weight (theoretical Mn) (Mn / theoretical Mn) is preferably 10.0 or less, more preferably 8.0 or less, further preferably 6.0 or less, even more preferably 5.0 or less, particularly preferably 4.5 or less, and best preferably 4.0 or less. On the other hand, from the perspective of productivity, when the monomer (Y) conversion rate is 5.0%, the polymer ratio (Mn / theoretical Mn) is preferably 0.5 or more, and more preferably 0.8 or more. The monomer (Y) conversion rate at the end of polymerization is not particularly limited, but can be adjusted according to the amount of organic compound (A) and monomer (Y) added, the target number average molecular weight, etc., and is usually 3 to 50%. The aforementioned conversion rate is preferably 10% or more, and more preferably 20% or more. When the aforementioned conversion rate is 5.0%, the number average molecular weight (Mn) of the polymer (measured value) is obtained as follows. GPC (gel permeation chromatography) measurements of the polymer are performed multiple times (but at least once between conversion rates of 1.0% and below 5.2%) from the start to the end of polymerization to obtain the number average molecular weight (Mn) at multiple conversion rates. Then, the number average molecular weight (Mn) is plotted against the conversion rate, and the number average molecular weight (Mn) of the polymer at the aforementioned conversion rate of 5.0% is obtained from a straight line passing through two points where the conversion rate is close to 5.0%. However, at least one of the two points is a point where the conversion rate is 1.0% or higher and below 5.2%. Specifically, the method described in the examples below is used. The theoretical number average molecular weight (theoretical Mn) of the polymer is obtained using the following formula. Theoretical Mn = Mohr ratio of monomer (Y) to organic compound (A) (Y / A) × Average molecular weight of monomer (Y) [g / mol] × (Conversion rate [%] / 100)

[0072] From the perspective of the high polymer controllability of the manufacturing method of the present invention, it is preferable to produce a block copolymer in the aforementioned polymerization step. Specifically, in the aforementioned polymerization step, it is preferable to sequentially perform controlled polymerization of monomer (Ya) and controlled polymerization of monomer (Yb) other than monomer (Ya) in the presence of organic compound (A) and free radical generator (B), thereby obtaining a block copolymer comprising polymer block (a) containing monomer (Ya) units and polymer block (b) containing monomer (Yb) units; more preferably, it is preferable to sequentially perform controlled polymerization of monomer (Ya) and controlled polymerization of monomer (Ya) and monomer (Yb) in the presence of organic compound (A) and free radical generator (B), thereby obtaining a block copolymer comprising polymer block (a) containing monomer (Ya) units and polymer block (ab) containing monomer (Ya) units and monomer (Yb) units. Hereinafter, this polymerization step will be described.

[0073] In the aforementioned polymerization steps, initially, the polymerization of monomer (Ya) is initiated by mixing monomer (Ya), other monomers (Yc) besides the desired monomer (Ya) and monomer (Yb), organic compound (A), and free radical generator (B) using the method described above. Then, after the number average molecular weight of the polymer block (a) containing monomer (Ya) reaches the target value, polymer block (b) containing monomer (Yb) units is synthesized by polymerizing monomer (Yb). Alternatively, the residual monomer (Ya) can be removed, and then monomer (Yb) can be added to the reaction solution to polymerize monomer (Yb), thereby synthesizing polymer block (b) containing monomer (Yb) units. Furthermore, monomer (Yb) can be added to the reaction solution without removing monomer (Ya), and the residual monomer (Ya) and monomer (Yb) can be copolymerized to synthesize copolymer block (ab) containing monomer (Ya) units and monomer (Yb) units. When adding monomer (Yb), additional monomer (Ya) or other monomers (Yc) may also be added as needed.

[0074] Alternatively, polymer blocks (ab) can be synthesized initially by mixing monomers (Ya), monomers (Yb), other monomers (Yc) as needed, organic compounds (A), and free radical generators (B), and polymer blocks (a) can be synthesized by polymerizing monomers (Ya) after the monomer (Yb) system is completely consumed or after the residual monomers (Yb) are removed.

[0075] Thus, binary block copolymers can be obtained by synthesizing polymer blocks (a), polymer blocks (b), or copolymer blocks (ab). Furthermore, ternary or higher-order multi-component block copolymers can be obtained by repeatedly polymerizing monomers (Ya), (Yb), or other monomers (Yc). From a cost perspective, the aforementioned block copolymers are preferably binary, ternary, or quaternary block copolymers, more preferably binary or ternary block copolymers, and even more preferably binary block copolymers. The bonding form of each block is preferably linear.

[0076] From the perspective that the properties derived from each block can be easily obtained, the ratio of the number average molecular weight (Mn) of each block to the number average molecular weight (Mn) of the block copolymer (Mn of the block / Mn of the block copolymer) is preferably 0.01 to 0.99. More preferably, the ratio is 0.05 or more, and even more preferably 0.1 or more. On the other hand, the ratio is preferably 0.95 or less, and even more preferably 0.9 or less.

[0077] The monomer (Ya) unit content in polymer block (a) is preferably 50 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, and especially preferably 90 mol% or more. The monomer (Yb) unit content in polymer block (a) is preferably less than 10 mol%, more preferably less than 5 mol%, and even more preferably less than 1 mol%. The monomer (Yb) unit content in polymer block (b) is preferably 50 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, and especially preferably 90 mol% or more. The monomer (Ya) unit content in polymer block (b) is preferably less than 10 mol%, more preferably less than 5 mol%, and even more preferably less than 1 mol. The content of monomer (Ya) units in the polymer block (ab) is preferably 1-99 mol%, more preferably 5-99 mol%, and even more preferably 10-90 mol%. The content of monomer (Yb) units in the polymer block (ab) is preferably 1-99 mol%, more preferably 5-99 mol%, and even more preferably 10-90 mol%.

[0078] Monomer (Ya), monomer (Yb), and other monomers (Yc) are not particularly limited, and can be used in combination as monomer (Y). Of particular, the aforementioned vinyl ester is preferred as one of monomers (Ya) and monomer (Yb). If the other monomer that can be used with the vinyl ester is a monomer other than vinyl ester, it is not particularly limited, but is preferably the aforementioned acrylate, the aforementioned olefin, or the aforementioned acrylic acid.

[0079] Among them, the special series: in the aforementioned polymerization step, in the presence of organic compound (A) and free radical generator (B), the controlled free radical polymerization of ethylene ester and the controlled free radical polymerization of ethylene ester and monomers other than ethylene ester are carried out sequentially to obtain ethylene ester block copolymers, which include ethylene ester polymer blocks and polymer blocks containing ethylene ester units and units derived from monomers other than ethylene ester.

[0080] In the aforementioned polymerization steps, it is preferable to terminate the polymerization reaction by adding a polymerization terminator when the number average molecular weight of the polymer and the conversion rate of monomer (Y) reach the target values. Examples of polymerization terminators include: 1,1-diphenylethylene; hydroxy aromatic compounds such as p-methoxyphenol, hydroquinone, cresol, t-butylcatechol, and p-nitrosophenol; quinone compounds such as benzoquinone and naphthoquinone; conjugated carboxylic acids such as muconic acid and sorbic acid; and phenoxythiazolinone. Thioethers such as distearate and dilaurate thiodipropionate; aromatic amines such as p-phenylenediamine and N-nitrosodiphenylamine; nitrogen oxides such as 2,2,6,6-tetramethylpiperidine 1-oxyl and 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl; and transition metal salts such as copper acetate, copper dithiocarbamate, and manganese acetate. Among these, 1,1-diphenylethylene, sorbic acid, and benzoquinone are preferred, with 1,1-diphenylethylene being even more preferred.

[0081] The mole number of the added polymerization terminator is preferably 1 to 100 moles relative to 1 mole of organic compound (A). If the mole number of the aforementioned polymerization terminator is too small, it will not be able to adequately capture the free radicals at the polymer ends, and the color of the obtained polymer may deteriorate. On the other hand, if the mole number of the aforementioned polymerization terminator is too large, the production cost may increase.

[0082] The temperature of the reaction solution during the termination step should be such that the polymerization terminator can react with the free radicals at the polymer terminator; preferably, it should be between 0 and 80°C. The time required for the termination step is typically between 1 minute and 5 hours.

[0083] After the polymerization step, it is acceptable to perform a removal step to remove organic compounds (A) and other substances contained in the obtained polymer. However, from the perspective of a good balance between environmental, safety, and cost considerations, it is preferable not to perform such a removal step. Organic compounds (A) are highly safe. Therefore, even without a removal step, the obtained polymer is highly safe.

[0084] As described above, the monomer (Y) used in the polymerization step preferably contains vinyl ester. That is, in the aforementioned polymerization step, it is preferable to carry out controlled free radical polymerization of vinyl ester in the presence of an organic compound (A) and a free radical generator (B) to obtain a vinyl ester-based polymer. Examples of the aforementioned vinyl ester-based polymers include: homopolymers of vinyl ester, random copolymers containing vinyl ester units and units derived from monomers other than vinyl ester, and vinyl ester-based block copolymers containing polymer blocks (a) containing vinyl ester units and polymer blocks (b) containing units derived from monomers other than vinyl ester. The vinyl ester-based polymers obtained in this way can be suitably used for various applications.

[0085] In addition, a saponification step is preferred, which involves saponifying the aforementioned ethylene ester polymer to convert the ethylene ester units into ethylene alcohol units, thereby obtaining an ethylene alcohol polymer.

[0086] In the saponification step, for example, a vinyl alcohol polymer can be obtained by saponifying the aforementioned vinyl ester polymer while it is dissolved in an alcohol. When the aforementioned vinyl ester polymer contains acrylate units, the acrylate units can be converted into acrylic units by adjusting the saponification conditions. In addition, acrylate units or acrylic units may sometimes form a lactone ring with adjacent vinyl alcohol units.

[0087] Regarding the alcohols used in the saponification reaction, examples include lower alcohols such as methanol and ethanol, with methanol being particularly suitable. Furthermore, the aforementioned alcohols can be aqueous or dehydrated alcohols. The alcohols used in the saponification reaction may also contain esters such as acetone, methyl acetate or ethyl acetate, or solvents such as toluene. Regarding the catalysts used in the saponification reaction, examples include alkali metal hydroxides such as potassium hydroxide and sodium hydroxide; alkaline catalysts such as sodium methoxide; and acidic catalysts such as mineral acids. Regarding the temperature of the saponification reaction, a suitable range is, for example, 20–80°C. If a gel-like product precipitates during the saponification reaction, pulverizing the product at this point, washing it, and then drying it can yield a vinyl alcohol-based polymer.

[0088] The saponification degree of the aforementioned vinyl alcohol polymers can be adjusted according to the application and is not particularly limited, but is typically 50-99.99 moles. In this invention, the saponification degree refers to the proportion (moles%) of the total number of vinyl alcohol units (including units derived from vinyl alcohol monomers that have formed lactone rings) in the vinyl alcohol polymer relative to the total number of vinyl ester units and vinyl alcohol units (including units derived from vinyl alcohol monomers that have formed lactone rings). The saponification degree can be determined by 1H-NMR measurement of the vinyl alcohol polymer.

[0089] The total amount of ethylene ester units and ethylene alcohol units in the aforementioned vinyl alcohol polymers is preferably 50 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more.

[0090] When the aforementioned ethylene ester-based block copolymer, comprising a polymer block (a) containing ethylene ester units and a polymer block (b) containing units derived from monomers other than ethylene esters, is saponified, an ethylene alcohol-based block copolymer can be obtained, comprising: a polymer block (a') containing ethylene alcohol units and a polymer block (b') containing units derived from monomers other than ethylene esters. Furthermore, when the aforementioned ethylene ester-based block copolymer, comprising a polymer block (a) containing ethylene ester units and a copolymer block (ab) containing ethylene ester units and units derived from monomers other than ethylene esters, is saponified, an ethylene alcohol-based block copolymer can be obtained, comprising: an ethylene alcohol-based polymer block (a') and a copolymer block (ab') containing ethylene alcohol units and units derived from monomers other than ethylene esters.

[0091] The number average molecular weight (Mn) of the polymer obtained by the manufacturing method of the present invention is not particularly limited, but is preferably 1,000 or higher. According to the manufacturing method of the present invention, high molecular weight polymers can be synthesized while precisely controlling molecular arrangement and terminal structure. Therefore, this manufacturing method is suitable for manufacturing polymers with high number average molecular weight (Mn). More preferably, the number average molecular weight (Mn) of the aforementioned polymer is 2,000 or higher, further preferably 4,000 or higher, even more preferably 10,000 or higher, particularly preferably 20,000 or higher, and most preferably 40,000 or higher. On the other hand, from the perspective of ease of operation, the number average molecular weight (Mn) of the polymer is preferably 1,000,000 or lower, more preferably 500,000 or lower, and further preferably 300,000 or lower. The number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) are values ​​determined by GPC using polymethyl methacrylate as a standard. The appropriate column system should be selected based on factors such as the solubility of the polymer in the solvent; tetrahydrofuran-based columns or HFIP-based columns may be suitable. Specific determination methods are as described in the examples.

[0092] The molecular weight distribution (Mw / Mn) of the polymer obtained by the manufacturing method of the present invention is not particularly limited, but is preferably 1.00 to 3.5. Polymerization is carried out through controlled free radical polymerization, thereby obtaining polymers with narrow molecular weight distributions. The molecular weight distribution (Mw / Mn) is more preferably 3.4 or less, further preferably 3.3 or less, and particularly preferably 3.2 or less.

[0093] In the manufacturing method of this invention, by using an organic compound (A), free radical polymerization is highly controlled, thus enabling the precise control of molecular arrangement and terminal structure while obtaining high molecular weight polymers. Furthermore, organic compound (A) is inexpensive and is industrially used as a food additive and flavoring agent with high safety; therefore, a step to remove organic compound (A) is unnecessary. Thus, the manufacturing method of this invention is environmentally friendly and cost-effective. The obtained polymer, utilizing its properties, can be suitable for applications in hygiene, daily necessities, construction and civil engineering, industry, agriculture, medicine, and food.

[0094] A suitable embodiment of the present invention is a composition for free radical polymerization, comprising an organic compound (A) as shown in formula (I) and a free radical generator (B), wherein the molar ratio (B / A) of (B) to (A) is 0.5 to 20. By using this composition, free radical polymerization of monomer (Y) can be carried out with high control. Furthermore, this composition for free radical polymerization has high safety. Therefore, methods, primarily the polymer manufacturing method described above, can be suitably used for the free radical polymerization of various monomers. Examples of the organic compound (A), free radical generator (B), and monomer (Y) used in the aforementioned composition for free radical polymerization include those used in the polymer manufacturing method.

[0095] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0096] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0097] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0098] The aforementioned composition for free radical polymerization preferably contains a monomer (Y). In this case, the molar ratio (Y / A) of the monomer (Y) relative to the organic compound (A) is preferably 300 to 30,000.

[0099] A free radical polymerization control agent comprising an organic compound (A) as shown in formula (I) below is also a suitable embodiment of the present invention. Regarding the organic compound (A) used as the free radical polymerization control agent, examples include those described above used in polymer manufacturing methods. During free radical polymerization, examples of free radical generators (B) and monomers (Y) that can be used with the aforementioned free radical polymerization control agent include those described above used in polymer manufacturing methods.

[0100]

[0101] [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring.]

[0102] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0103] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.]

[0104] Polymers having the end structures shown in formula (V) or (VI) below are suitable embodiments of the present invention. [In formula (V), R1 is an alkenyl or aryl group, and R2 is a group represented by formula (II) or (III) below. R1 and R2 can also be linked together to form a ring. * indicates a bonding bond.]

[0105] [In equation (VI), R1 and R2 are synonymous with those in equation (V) above, and * denotes a bonding bond.]

[0106] [In formula (II), R represents a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl group, and * indicates a bonding bond.]

[0107] [In equation (III), R3 is synonymous with equation (II) above, and * represents a bonding bond.] [Example]

[0108] The present invention will be further described in detail below using examples.

[0109] [Organic compound (A)] trans-cinnamic acid Methyl cinnamate • trans-benzalacetone ·Cinnamyl alcohol ·4-Phenylon-2-Butanone β-ionone Coumarin [Free radical generator (B)] ·[2,2'-Azobis(4-methoxy-2,4-dimethylpentanonitrile)](V-70) [monomer] Vinyl acetate (VAc) N-vinylpyrrolidone (VP) Methyl acrylate (MA) Ethylene (Et) Styrene N,N-Dimethylacrylamide (DEAA) Maleic anhydride (MAn) [Polymerization Inhibitor] ·1,1-Diphenylethylene (1,1-DPEt)

[0110] [Number Average Molecular Weight (Mn)] The number-average molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the polymer were determined using a gel permeation chromatography apparatus manufactured by Shimadzu Corporation. The determination conditions were any of the following. <Condition 1> Tube Column: Tetrahydrofuran-based tube column "KF-806M" manufactured by Showa Denko Co., Ltd. Standard sample: polymethyl methacrylate Solvent and mobile phase: Tetrahydrofuran (THF) Flow rate: 1.0 mL / min Temperature: 40℃ Sample solution concentration: 0.2% by mass (filtered using a 0.45 μm open filter). Injection volume: 100μL Detector: RI <Condition 2> Tube String: Two HFIP system tube strings "GMHHR-H(S)" manufactured by Tosoh Corporation, connected in series. Standard sample: polymethyl methacrylate Solvent and mobile phase: Sodium trifluoroacetate-HFIP solution (20 mM) Flow rate: 0.2 mL / min Temperature: 40℃ Sample solution concentration: 0.1 wt% (filtered using a 0.45 μm open filter) Injection volume: 10μL Detector: RI

[0111] [Theoretical Number Average Molecular Weight (Theoretical Mn)] The theoretical number average molecular weight (theoretical Mn) for a given conversion rate is obtained by the following formula. Theoretical Mn = Mohr ratio of monomer (Y) to organic compound (A) (Y / A) × Average molecular weight of monomer (Y) [g / mol] × (Conversion rate [%] / 100)

[0112] [Aggregational Control] The following were considered to indicate good controllability: the ratio (Mn / theoretical Mn) of the polymer at a monomer (Y) conversion rate of 5.0% to the theoretical number average molecular weight (Mn) was less than 10.0, and Mn increased with increasing conversion rate. The aforementioned number average molecular weight (Mn) of the polymer at a conversion rate of 5.0% was obtained as follows: GPC (gel permeation chromatography) measurements of the polymer in the reaction solution were performed multiple times from the start to the end of polymerization (but at least once between a conversion rate of 1.0% and less than 5.2%), thereby obtaining the number average molecular weight (Mn) at multiple conversion rates. Figure 1 is a graph obtained by plotting the number average molecular weight (Mn) relative to the conversion rate in Example 1. As shown in Figure 1, after plotting the number average molecular weight (Mn) (vertical axis, linear scale) against the conversion rate (horizontal axis, linear scale), the number average molecular weight (Mn) of the polymer at a conversion rate of 5.0% was obtained from the straight line passing through two points where the conversion rate is close to 5.0%. However, it is assumed that at least one of the two points is used when the conversion rate is above 1.0% and below 5.2%.

[0113] [Amount of Et dissolved in VAc] The amount of Et dissolved in VAc was calculated as follows. Table 1 in *Nature Chemistry*, volume 6, pages 179-187 (2014), shows that the Et molar fractions in the obtained VAc / Et random copolymers obtained by copolymerizing VAc and Et under Et pressures of 10, 25, and 50 [bar] are 0.13, 0.33, and 0.54, respectively. The correlation between the Et molar fraction (Fet) in the copolymers obtained by plotting Et pressure (E) [bar] at four points with the origin (Et content is 0) and the origin, and the approximate curve obtained using the least squares method, is expressed by the following formula. Fet = 0.0108E + 0.0208

[0114] The molar ratio (F=Fvac / Fet) of the VAc / Et copolymer relative to the Et unit is expressed by the following formula. F=(1-Fet) / Fet

[0115] However, in the fourth edition of the Polymer Handbook, pages II / 273, it is recorded that the copolymerization reactivity ratios of VAc and Et are r(VAc) = 1.03 and r(Et) = 0.88. Generally speaking, the Mayo-Lewise equation holds true between the molar ratio of the monomers [the molar ratio of VAc to Et (D = Dvac / Det)], the molar ratio of the monomer units contained in the obtained VAc / Et copolymer [the molar ratio of VAc units to Et units (F = Fvac / Fet)], and the copolymerization reactivity ratio of the monomers, and therefore (D) is expressed by the following formula. D=(F-1+((1-F) ^2+3.6256F) ^0.5) / 2.06

[0116] Then, the total amount of VAc and Et in the copolymerization of VAc and Et (Yvac+et) (moles) is obtained by the following formula using the amount of VAc (Yvac) (moles) in the copolymerization and the mole ratio D. (Yvac+et)=(Yvac)+(Yvac) / D

[0117] [Content of methyl acrylate monomer units (U) in vinyl acetate block copolymers] The content (U) (moles%) of methyl acrylate monomer units in the vinyl acetate block copolymer was determined using the following method. 1H-NMR analysis of the vinyl acetate block copolymer was performed. The integral value (4.8 ppm) of the peak of the methine proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit was set as T, and the integral value (3.6 ppm) of the peak of the side-chain proton (-CH₂CH(COOCH₃)-) derived from the methyl acrylate monomer unit was set as S. The content (U) (moles%) of acrylate monomer units in the vinyl acetate block copolymer was calculated using the following formula. Furthermore, the content of MA units in the copolymer block containing VAc and MA units was determined using the content (U) and the number-average molecular weight (Mn) of each polymer block. (U)(Moll%) = (S / 3) / (S / 3+T)×100

[0118] [Content of Et monomer units (R) in vinyl acetate block copolymers] The content (R) (moles%) of Et monomer units in vinyl acetate block copolymers was determined using the following method. 1H-NMR analysis of the vinyl acetate block copolymers was performed. The integral value (4.8 ppm) of the peak of the methylene proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit was set as T, and the integral values ​​(1.0–1.8 ppm) of the peaks of the methylene proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit and the main chain proton (-CH₂CH₂-) of the Et unit were set as Q. The content (R) (moles%) of Et units in the vinyl acetate block copolymers was calculated using the following formula. Furthermore, the content of Et units in copolymer blocks containing VAc and Et units was determined using the content (R) and the number-average molecular weight (Mn) of each polymer block. (R)(Moll%) = (Q-2T) / 4 / ((Q-2T) / 4+T)×100

[0119] [Content of acrylic monomer units (O) in vinyl acetate block copolymers] The content (O) (moles%) of acrylic monomer units in vinyl acetate block copolymers was determined using the following method. 1H-NMR analysis of the vinyl acetate block copolymers was performed. The integral value (4.8 ppm) of the peak of the methylene proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit was set as T, and the integral value (12.2 ppm) of the peak of the side-chain proton (-CH₂CH(COOH)-) derived from the acrylic monomer unit was set as P. The content (O) (moles%) of acrylic monomer units in the vinyl acetate block copolymers was calculated using the following formula. Furthermore, the content of AA units in copolymer blocks containing VAc and AA units was determined using the content (O) and the number-average molecular weight (Mn) of each polymer block. (O)(Moll%) = P / (P+T)×100

[0120] [Content of N,N-dimethylacrylamide monomer units (M) in vinyl acetate block copolymers] The content (M) (moles%) of N,N-dimethylacrylamide units in vinyl acetate block copolymers was determined using the following method. 1H-NMR analysis of the vinyl acetate block copolymers was performed. The integral value (4.8 ppm) of the peak of the methylene proton (-CH₂CH(OCOCH₃)-) from the vinyl acetate monomer unit was set as T, and the integral value (3.0 ppm) of the peak of the side-chain proton (-CH₂CH(CONH(CH₃)₂-) from the N,N-dimethylacrylamide monomer unit was set as N. The content (M) (moles%) of N,N-dimethylacrylamide monomer units in the vinyl acetate block copolymers was calculated using the following formula. Furthermore, the content of DMAA units in copolymer blocks containing VAc and DMAA units was determined using the content (M) and the number-average molecular weight (Mn) of each polymer block. (M)(Moll%) = (N / 6) / ((N / 6)+T)×100

[0121] [Content of maleic anhydride monomer units in vinyl acetate block copolymers (J)] The content (J) (moles%) of maleic anhydride units in vinyl acetate block copolymers was determined using the following method. 1H-NMR analysis of the vinyl acetate block copolymers was performed. The integral value (5.1 ppm) of the peak of the methylene proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit was set as K, and the integral value (3.0 ppm) of the peak of the main chain proton (-CHCH(CO₂CO)-) derived from the maleic anhydride monomer unit was set as L. The content (J) (moles%) of maleic anhydride monomer units in the vinyl acetate block copolymers was calculated using the following formula. Furthermore, the content of MAn units in the copolymer blocks containing VAc and MAn units was determined using the content (J) and the number-average molecular weight (Mn) of each polymer block. (J)(Moll%)=(L / 2) / ((L / 2)+K)×100

[0122] [In the polymer, the content (W) of the terminal structural units shown in formula (V) or (VI)] In the polymer, the content (W) (mol%) of the terminal structural unit shown in formula (V) or (VI) is calculated as follows. For example, the content of methyl cinnamate added to the ends of polyvinyl acetate was quantified. Polyvinyl acetate was dissolved in methanol and repeatedly reprecipitated with hexane to remove methyl cinnamate not added to the ends of polyvinyl acetate. The recovered polyvinyl acetate was dried at 40°C for 24 hours using a vacuum dryer, and the resulting polyvinyl acetate was subjected to 1H-NMR determination. The integral value (4.8 ppm) H of the peak of the methylene proton (-CH₂CH(OCOCH₃)-) derived from the vinyl acetate monomer unit and the integral value G of all peaks detected in the range of 7.1–7.5 ppm of the aromatic ring derived from methyl cinnamate were calculated. Furthermore, when calculating the integral values ​​of 7.1 to 7.5 ppm, considering the visible tilt of the baseline, the area values ​​of each peak were calculated. Using the integral value H and the integral value G divided by the number of hydrogen atoms bonded to the aromatic ring (G / number of hydrogen atoms bonded to the aromatic ring), the content (W) was obtained from [(G / number of hydrogen atoms bonded to the aromatic ring) / H]. (W)(Moll%) = (G / 5) / H × 100

[0123] [The molar ratio (F) of the terminal structure relative to the number of polymer chains shown in formula (V) or (VI)] The molar ratio (F) of the terminal structure shown in formula (V) or (VI) relative to the number of polymer chains is calculated as follows. Using the content (W), Mn, and molecular weight of the terminal structural unit shown in formula (V) or (VI) in the polymer, the molar ratio (F) is obtained from [W / (Mn / molecular weight of monomer unit × 100)]. When the molar ratio (F) is 1, it means that the structural unit shown in formula (V) or (VI) is introduced into the single end of all polymer chains; the closer it is to 1, the better the controllability. (F)=W / (Mn / 86×100)

[0124] [Example 1] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and a free radical generator inlet, 900 parts by mass of VAc were added, followed by the introduction of nitrogen into the reactor for inert gas substitution. 100 parts by mass of VAc, 0.22 parts by mass of cinnamic acid (as organic compound (A)), and 0.45 parts by mass of V-70 (as free radical generator (B)) were added to a preparation container. After dissolution, nitrogen was introduced for inert gas substitution. The solution from the preparation container was added to the reactor, and the reactor was heated to 50°C with stirring. Sampling was performed, and the polymerization was confirmed by the concentration of the solid components. The number-average molecular weight (Mn) at a VAc conversion rate of 3.9% by mass was 86,800, the theoretical number-average molecular weight (theoretical Mn) was 26,800, and the ratio (Mn / theoretical Mn) was 3.2. When the VAc conversion rate was 9.5% by mass, the number average molecular weight (Mn) was 132,800, the theoretical number average molecular weight (theoretical Mn) was 65,300, and the ratio (Mn / theoretical Mn) was 2.0. When the VAc conversion rate was 12.7% by mass, the number average molecular weight (Mn) was 166,900, the theoretical number average molecular weight (theoretical Mn) was 87,100, and the ratio (Mn / theoretical Mn) was 1.9. When the VAc conversion rate reached 22% by mass, 1.31 parts by mass of 1,1-DPEt was added as a polymerization terminator. At this point, the number average molecular weight (Mn) was 226,400, the theoretical number average molecular weight (theoretical Mn) was 149,300, the ratio (Mn / theoretical Mn) was 1.5, and the molecular weight distribution (Mw / Mn) was 2.57. Unreacted VAc was removed by vacuum distillation from the solution to recover polyvinyl acetate (PVC). The recovered polyvinyl acetate was then dried at 40°C for 24 hours using a vacuum dryer. Table 1 shows the details of the polymerization steps described above. Figure 1 is a graph plotting the number average molecular weight (Mn) relative to the conversion rate of VAc. From Figure 1, the ratio (Mn / theoretical Mn) of the polymer's number average molecular weight (Mn) (measured value) to the theoretical number average molecular weight (theoretical Mn) when the VAc conversion rate is 5.0% is calculated to be 3.0.

[0125] [Example 2] <Aggregation Steps> Except for the addition of 0.24 parts by mass of methyl cinnamate as organic compound (A), heating to 50°C and stirring, the polymerization reaction was carried out in the same manner as in Example 1. After adding a polymerization terminator, the reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of polyvinyl acetate. Details are shown in Table 1.

[0126] <Saponification Steps> Next, in the same reactor as described above, the concentration of the methanol solution was adjusted so that 1834 parts by mass of methanol were obtained relative to 100 parts by mass of polyvinyl acetate. The water bath was then heated and stirred until the internal temperature reached 40°C. A methanol solution containing 66.4 parts by mass of sodium hydroxide (concentration 14% by mass, 9.3 parts by mass of sodium hydroxide) was added. A saponification reaction was carried out at 65°C for 1 hour with the methanol solution containing the 5% by mass of polyvinyl acetate prepared in this manner. After dehydration, phenolphthalein solution was added to the washing solution (methanol), and washing was performed with methanol until no alkaline reaction was observed, thus removing sodium hydroxide and sodium acetate. The solid obtained by centrifugation and dehydration was dried at 40°C for 24 hours using a vacuum dryer, thereby obtaining white polyvinyl alcohol. The degree of saponification was 99.9%.

[0127] [Example 3] <Aggregation Steps> Except for the addition of 0.15 parts by mass of methyl cinnamate as organic compound (A), 0.29 parts by mass of V-70 as free radical generator (B), heating to a reactor temperature of 45°C, and the addition of 0.84 parts by mass of 1,1-DPEt as a terminator, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0128] [Example 4] <Aggregation Steps> Except for the addition of 0.09 parts by mass of methyl cinnamate as organic compound (A), 0.18 parts by mass of V-70 as free radical generator (B), heating to a reactor temperature of 40°C, and the addition of 0.52 parts by mass of 1,1-DPEt as a terminator, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0129] [Example 5] <Aggregation Steps> Except for the addition of 1.88 parts by mass of methyl cinnamate as organic compound (A), 35.81 parts by mass of V-70 as free radical generator (B), heating to a reactor temperature of 45°C, and the addition of 10.47 parts by mass of 1,1-DPEt as a terminator, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0130] [Example 6] <Aggregation Steps> Except for the addition of 0.24 parts by mass of methyl cinnamate as organic compound (A) and 0.22 parts by mass of V-70 as free radical generator (B), the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0131] [Example 7] <Aggregation Steps> Except for the addition of a total of 1000 parts by mass of N-vinylpyrrolidone as monomer (Y), 0.18 parts by mass of methyl cinnamate as organic compound (A), and 0.35 parts by mass of V-70 as free radical generator (B), the polymerization reaction was carried out in the same manner as in Example 1 to obtain polyvinylpyrrolidone.

[0132] [Example 8] <Aggregation Steps> Except for the addition of 0.24 parts by mass of methyl cinnamate as organic compound (A), heating to a reactor temperature of 65°C, and the addition of 0.81 parts by mass of sorbic acid as a terminator, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0133] [Example 9] <Aggregation Steps> Except for the addition of 0.24 parts by weight of methyl cinnamate as organic compound (A), 25.0 parts of methanol as solvent, and heating to a reactor temperature of 60°C with stirring, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0134] [Example 10] <Aggregation Steps> Except for the addition of 1000 parts by mass of styrene as monomer (Y), 0.18 parts by mass of trans-benzyl acetone as organic compound (A), 0.37 parts by mass of V-70 as free radical generator (B), and 0.81 parts by mass of sorbic acid as terminator, the polymerization reaction was carried out in the same manner as in Example 1 to obtain polystyrene. Details are shown in Table 1.

[0135] [Example 11] <Aggregation Steps> Except for the addition of 0.21 parts by mass of trans-benzyl acetone as organic compound (A) and heating to a reactor temperature of 60°C, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0136] [Example 12] <Aggregation Steps> Except for the addition of 0.21 parts by mass of coumarin as organic compound (A), heating to a reactor temperature of 45°C, and stirring, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0137] [Example 13] <Aggregation Steps> Except for the addition of 0.19 parts by mass of cinnamyl alcohol as organic compound (A) and the heating to bring the reactor temperature to 60°C, the polymerization reaction was carried out in the same manner as in Example 1. Details are shown in Table 1.

[0138] [Example 14] <Aggregation Steps> Except for the addition of 0.28 parts by mass of β-ionone as organic compound (A) and heating to a reactor temperature of 30°C, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 1.

[0139] [Comparative Example 1] <Aggregation Steps> Except for the addition of 0.22 parts by weight of 4-phenyl-2-butanone to replace organic compound (A) and heating to a reactor temperature of 60°C, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 2.

[0140] [Comparative Example 2] <Aggregation Steps> Except for the absence of organic compound (A) and the heating to a reactor temperature of 30°C, the polymerization reaction was carried out in the same manner as in Example 1, and polyvinyl acetate was obtained. Details are shown in Table 2.

[0141] [Comparative Example 3] <Aggregation Steps> Except for the addition of 0.24 parts by mass of methyl cinnamate as organic compound (A) and 0.09 parts by mass of V-70 as free radical generator (B), the polymerization reaction was carried out in the same manner as in Example 1. Polymerization proceeded almost no further after 5 hours, and was therefore stopped. Details are shown in Table 2.

[0142] [Example 15] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.24 parts by mass of methyl cinnamate (as organic compound (A)), and 0.45 parts by mass of V-70 (as free radical generator (B)) were added, and nitrogen was introduced after dissolution for inert gas substitution. The solution from the preparation vessel was added to the reactor, and the reactor was heated to 45°C with stirring. Samples were taken to confirm polymerization progress based on solids concentration. When the VAc conversion reached 8.4% by mass, 30.00 parts by mass of MA were added. The number-average molecular weight (Mn) of the polymer at 8.4% by mass conversion was 150,700. The calculated molar ratio (Y / A) was 8240. Heating and stirring continued, and polymerization was confirmed by monitoring the solids concentration. Simultaneously, GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and MA reached 17.4% by mass, 1.31 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number average molecular weight (Mn) at this point was 233,700. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contained 9 mol of MA units, and the copolymer block containing VAc and MA units contained 25 mol of MA units.

[0143] <Saponification Steps> Next, in the same reactor as described above, the concentration of the methanol solution was adjusted so that 1834 parts by mass of methanol were obtained relative to 100 parts by mass of the vinyl acetate block copolymer. The mixture was then heated in a water bath with stirring until the internal temperature reached 40°C. A methanol solution containing 66.4 parts by mass of sodium hydroxide (concentration 14% by mass, 9.3 parts by mass of sodium hydroxide) was added. The resulting 5% by mass vinyl acetate block copolymer solution was saponified at 65°C for 1 hour. The saponified product obtained after dehydration was then treated with 46.5 parts by mass of sodium hydroxide, 2000 parts by mass of dehydrated methanol, and 210 parts by mass of deionized water, and further heated at 65°C for 1 hour. After dehydration, phenolphthalein solution was added to the washing solution (methanol), and the mixture was washed with methanol until no alkaline reaction was observed, thus removing sodium hydroxide and sodium acetate. The solid obtained from centrifugal dehydration was dried at 40°C for 24 hours using a vacuum dryer to obtain a white vinyl alcohol block copolymer (vinyl alcohol polymer block copolymer - a binary block copolymer containing vinyl alcohol monomer units and acrylic monomer units). The degree of saponification was 99.9%. Details are shown in Table 2.

[0144] [Example 16] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.24 parts by mass of methyl cinnamate (as organic compound (A)), and 0.45 parts by mass of V-70 (as free radical generator (B)) were added, dissolved, and then nitrogen was introduced for inert gas substitution. The solution from the preparation vessel was added to the reactor, heated to 45°C, and stirred. Sampling was performed to confirm polymerization progress based on solids concentration. When the VAc conversion reached 10.2% by mass, the Et pressure was adjusted to an internal pressure of 9 bar. The calculated Y / A molar ratio was 9120. The number-average molecular weight (Mn) of the polymer at a conversion of 10.2% by mass was 176,600. Heating and stirring continued, and polymerization was confirmed by monitoring the solids concentration. Simultaneously, GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and Et reached 18.3% by mass, 1.31 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number average molecular weight (Mn) at this point was 203,600. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contained 2 mol% Et units, and the copolymer block containing VAc and Et units contained 12 mol% Et units.

[0145] <Saponification Steps> Next, the saponification reaction was carried out in the same manner as in Example 2, yielding a white vinyl alcohol block copolymer (vinyl alcohol polymer block copolymer - a binary block copolymer containing copolymer blocks of vinyl alcohol monomer units and Et units). Details are shown in Table 2.

[0146] [Example 17] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc and 180 parts by mass of MA were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.63 parts by mass of methyl cinnamate (as organic compound (A)), and 3.58 parts by mass of V-70 (as free radical generator (B)) were added, and nitrogen was introduced after dissolution for inert gas substitution. The calculated molar ratio (Y / A) was 3000. The solution from the preparation vessel was added to the reactor, and the reactor was heated to 40°C with stirring. Sampling was performed, and the polymerization was confirmed by solids concentration. ¹H-NMR confirmed that MA was completely consumed at a combined conversion of 25.0% by mass for VAc and MA [molar ratio (acrylate / vinyl ester) was less than 0.00001]. The number-average molecular weight (Mn) at this point was 109,400. Immediately afterwards, 4000.00 parts by mass of VAc were added. The combined conversion of VAc and MA at this point was 5.8% by mass, and the calculated molar ratio (Y / A) was 13000. Heating and stirring continued, and the polymerization was confirmed by the concentration of solids. GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and MA reached 20.3% by mass, 3.49 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number-average molecular weight (Mn) at this point was 195,500. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contains 19 mol of MA units, and the copolymer block containing VAc units and MA units contains 63 mol of MA units.

[0147] <Saponification Steps> Next, the saponification reaction was carried out in the same manner as in Example 2, yielding a white vinyl alcohol-based block copolymer. Details are shown in Table 2.

[0148] [Example 18] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.24 parts by mass of methyl cinnamate (as organic compound (A)), and 1.34 parts by mass of V-70 (as free radical generator (B)) were added, dissolved, and then nitrogen was introduced for inert gas substitution. The solution from the preparation vessel was added to the reactor, heated to 40°C, and stirred. Sampling was performed, and polymerization was confirmed by the concentration of solid components. When the conversion of VAc reached 9.7% by mass, 83.72 parts by mass of AA were added. The number-average molecular weight (Mn) of the polymer at a conversion of 9.7% by mass was 104,900. The calculated molar ratio (Y / A) was 8100. Heating and stirring continued, and polymerization was confirmed by monitoring the solids concentration. GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and AA reached 16.2% by mass, 1.31 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number average molecular weight (Mn) at this point was 144,400. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contained 8 mol of AA units, and the copolymer block containing VAc and AA units contained 20 mol of AA units.

[0149] <Saponification Steps> Next, the saponification reaction was carried out in the same manner as in Example 2, yielding a white vinyl alcohol-based block copolymer. Details are shown in Table 2.

[0150] [Example 19] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.24 parts by mass of methyl cinnamate (as organic compound (A)), and 1.34 parts by mass of V-70 (as free radical generator (B)) were added, and nitrogen was introduced after dissolution for inert gas substitution. The solution from the preparation vessel was added to the reactor, and the reactor was heated to 40°C with stirring. Samples were taken to confirm polymerization progress based on solids concentration. When the VAc conversion reached 8.4% by mass, 115.10 parts by mass of DMAA were added. The number-average molecular weight (Mn) of the polymer at 8.4% by mass conversion was 114,600. The calculated molar ratio (Y / A) was 8100. Heating and stirring continued, and polymerization was confirmed by monitoring the solids concentration. GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and DMAA reached 19.9% ​​by mass, 1.31 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number average molecular weight (Mn) at this point was 145,000. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contained 6 mol of DMAA units, and the copolymer block containing VAc and DMAA units contained 20 mol of DMAA units.

[0151] <Saponification Steps> Next, the saponification reaction was carried out in the same manner as in Example 2, yielding a white vinyl alcohol-based block copolymer. Details are shown in Table 2.

[0152] [Example 20] <Aggregation Steps> In a reactor equipped with a stirrer, reflux cooling pipe, and an inlet for adding free radical generator (B), 900 parts by mass of VAc were added, and nitrogen was introduced into the reactor for inert gas substitution. In a preparation vessel, 100 parts by mass of VAc, 0.24 parts by mass of methyl cinnamate (as organic compound (A)), and 1.34 parts by mass of V-70 (as free radical generator (B)) were added, dissolved, and then nitrogen was introduced for inert gas substitution. The solution from the preparation vessel was added to the reactor, heated to 40°C, and stirred. Samples were taken to confirm polymerization progress based on solids concentration. When the VAc conversion reached 7.4% by mass, 113.95 parts by mass of MAn were added. The number-average molecular weight (Mn) of the polymer at 7.4% by mass conversion was 74,400. The calculated molar ratio (Y / A) was 8100. Heating and stirring continued, and polymerization was confirmed by monitoring the solids concentration. Simultaneously, GPC and 1H-NMR analyses were performed on the sampled polymer. When the combined conversion of VAc and Man reached 18.1% by mass, 1.31 parts by mass of 1,1-DPEt were added as a polymerization terminator. The number average molecular weight (Mn) at this point was 100,800. The reactor was connected to a vacuum line, and unreacted VAc was removed by azeotropic addition of methanol, thereby obtaining a methanol solution of the vinyl acetate block copolymer. Details are shown in Table 2. The obtained vinyl acetate block copolymer contained 8 mol of MAn units, and the copolymer block containing VAc and MAn units contained 13 mol of MAn units.

[0153] <Saponification Steps> Next, the saponification reaction was carried out in the same manner as in Example 2, and a white vinyl alcohol block copolymer was obtained. Details are shown in Table 2.

[0154] [Example 21] <Aggregation Steps> In the polymerization of Example 1, a sample was taken just before the addition of the polymerization terminator and added dropwise to hexane to recover the polymer through reprecipitation. The polymer was dissolved in methanol and added dropwise again to hexane, followed by drying to obtain polyvinyl acetate. The content (W) of the trans-cinnamic acid-derived structure at the end of the polyvinyl acetate was 0.036 mol%. The mol ratio (F) of the trans-cinnamic acid-derived structure to the amount at the end of the polyvinyl acetate was 0.95. Details are shown in Table 2.

[0155] [Example 22] <Aggregation Steps> In the polymerization of Example 5, a sample was taken just before the addition of the polymerization terminator and added dropwise to hexane to recover the polymer through reprecipitation. The polymer was dissolved in methanol and added dropwise again to hexane, and then dried to obtain polyvinyl acetate. The content (W) of the structure derived from methyl cinnamate at the end of the polyvinyl acetate was 0.48 mol%, and the mol ratio (F) of the structure derived from methyl cinnamate to the amount at the end of the polyvinyl acetate was 0.97.

[0156] [Table 1] A B Y B / A Y / A temperature [℃] time [h] Conversion rate [%] Mn Theoretical Mn Mn / Theoretical Mn Mn / Theoretical Mn (Conversion rate 5%) Mw / Mn Example 1 trans-cinnamic acid V70 VAc 1 8000 50 1.5 3.9 86800 26800 3.2 3.0 1.85 2.5 9.5 132800 65300 2.0 2.14 3.0 12.7 166900 87100 1.9 2.38 3.8 21.7 226400 149300 1.5 2.57 Example 2 Methyl cinnamate V70 VAc 1 8000 50 0.8 4.5 88100 31200 2.8 2.7 1.89 1.3 8.7 122200 59600 2.1 2.07 1.6 13.4 154900 92200 1.7 2.27 2.2 20.9 208500 143700 1.5 2.57 Example 3 Methyl cinnamate V70 VAc 1 12500 45 1.0 2.8 109900 30100 3.7 2.5 1.83 1.5 4.0 127700 42500 3.0 1.88 1.6 4.6 132300 49600 2.7 1.94 Example 4 Methyl cinnamate V70 VAc 1 20000 40 1.9 2.9 161641 50600 3.2 2.6 1.94 3.2 6.8 232750 116600 2.0 2.05 3.7 9.4 240575 161400 1.5 2.38 4.2 13.5 312213 231600 1.3 2.20 Example 5 Methyl cinnamate V70 VAc 10 1000 45 1.7 5.1 7300 4500 1.6 1.6 1.55 2.7 12.0 11100 10300 1.1 2.07 3.2 17.7 16000 15300 1.0 2.35 3.5 20.7 17400 17900 1.0 2.74 Example 6 Methyl cinnamate V70 VAc 1 8000 50 4.8 2.1 66200 14600 4.5 1.4 1.96 5.8 3.1 74000 21400 3.5 2.14 Example 7 Methyl cinnamate V70 VP 1 8000 50 0.4 3.9 142300 34900 4.1 3.6 2.00 0.6 7.4 169200 66100 2.6 2.15 0.8 12.2 195700 108400 1.8 2.28 1.1 21.4 223300 190300 1.2 2.37 Example 8 Methyl cinnamate V70 VAc 1 8000 65 0.7 3.9 73300 26900 2.7 2.4 1.75 0.9 7.7 90700 52900 1.7 2.03 1.2 16.5 146100 113700 1.3 2.25 1.5 25.2 201400 173400 1.2 2.24 Example 9 1) Methyl cinnamate V70 VAc 1 8000 60 0.2 4.0 52300 27300 1.9 1.7 1.85 0.5 6.4 63200 43800 1.4 1.94 1.1 13.6 91200 93700 1.0 2.13 1.5 17.5 110300 120600 0.9 1.99 Example 10 trans-benzylacetone V70 Sty 1 8000 50 0.9 2.5 63800 20900 3.1 1.9 1.66 1.2 3.2 66400 27000 2.5 1.66 1.8 4.2 70800 35000 2.0 1.69 3.0 7.3 85100 61100 1.4 1.75 Example 11 trans-benzylacetone V70 VAc 1 8000 60 1.3 2.0 53700 13800 3.9 2.7 1.70 2.6 6.1 92600 41900 2.2 2.20 3.6 12.9 162200 88700 1.8 2.31 5.1 22.3 207100 153100 1.4 2.72 Example 12 Coumarin V70 VAc 1 8000 45 0.1 2.2 197900 15500 12.8 7.7 1.90 0.6 6.7 205300 46300 4.4 2.00 0.9 10.9 242300 74700 3.2 1.93 1.5 19.1 289200 131400 2.2 2.02 Example 13 Cinnamyl alcohol V70 VAc 1 8000 60 0.5 3.2 141400 22000 6.4 5.4 1.80 2.5 10.3 157300 70800 2.2 1.83 3.5 13.3 172243 91700 1.9 1.86 4.5 15.3 174300 105100 1.7 1.91 Example 14 β-ionone V70 VAc 1 8000 30 0.2 3.0 212900 20800 10.2 6.9 1.84 0.5 6.0 218500 41300 5.3 1.83 1.0 10.6 211500 72900 2.9 1.94 1.8 16.0 233800 109900 2.1 1.82 Comparative Example 1 4-Phenylon-2-Butanone V70 VAc 1 8000 60 0.1 2.9 302700 20000 15.1 10.8 1.91 0.2 7.6 286400 52600 5.4 1.96 0.5 14.1 311400 97200 3.2 1.97 0.7 19.4 311000 133500 2.3 2.01 Comparative Example 2 - V70 VAc 1 8000 30 0.0 3.5 249200 - - - 2.06 0.1 7.1 277100 - - 1.93 0.3 12.1 271800 - - 1.99 0.6 22.4 259100 - - 2.11 1) Solution polymerization was carried out by adding methanol to the reactor.

[0157] [Table 2] A B Y B / A Y / A temperature [℃] time [h] Conversion rate [%] Mn Theoretical Mn Mn / Theoretical Mn Mn / Theoretical Mn (Conversion rate 5%) Mw / Mn Comparative Example 3 Methyl cinnamate V70 VAc 0 8000 50 0.5 0.1 - 688 - - - 1.0 0.2 - 1376 - - 3.0 0.3 - 2064 - - 5.0 0.3 - 2064 - - Example 15 Methyl cinnamate V70 VAc 1 8000 2) 45 1.1 2.7 78500 18700 4.2 2.9 1.79 1.7 4.4 91900 30100 3.1 1.93 2.0 5.5 105200 37900 2.8 1.96 3.0 8.4 150700 57600 2.6 2.32 AND 8240 3) 3.1 10.4 151996 74000 2.1 2.47 3.3 12.6 188387 89600 2.1 3.00 3.6 16.3 210269 115700 1.8 3.20 4.1 17.4 233697 123400 1.9 3.08 Example 16 Methyl cinnamate V70 VAc 1 8000 2) 45 1.5 3.2 109900 22100 5.0 4.0 1.91 2.0 6.1 145600 41800 3.5 1.88 2.3 8.8 164700 60700 2.7 2.05 2.5 10.2 176600 70000 2.5 2.08 And 1) 9120 3) 2.6 11.9 177900 81900 2.2 2.21 2.9 14.7 187400 101000 1.9 2.25 3.1 15.9 193200 109600 1.8 2.21 3.3 18.3 203600 126000 1.6 2.15 Example 17 Methyl cinnamate V70 VAc+MA 3 3000 2) 40 1.5 2.1 31700 5500 5.8 4.7 2.94 2.0 8.6 73500 22200 3.3 2.60 2.6 16.9 102800 43600 2.4 2.37 3.3 25.0 109400 64500 1.7 2.31 VAc 13000 3) 5.1 7.8 140037 87696 1.6 2.10 5.6 10.3 161800 114700 1.4 2.05 6.1 15.6 184900 174400 1.1 2.17 6.7 20.3 195500 226600 0.9 2.46 Example 18 Methyl cinnamate V70 VAc 3 8000 2) 40 1.4 3.2 63700 22000 2.9 2.4 1.83 1.9 5.3 84300 36500 2.3 1.99 2.3 8.3 77100 57100 1.4 2.50 2.6 9.7 104900 66600 1.6 2.22 AA 8100 3) 2.7 11.1 122700 77100 1.6 1.88 2.8 13.8 125000 96100 1.3 1.95 3.2 16.2 144400 112800 1.3 2.09 Example 19 Methyl cinnamate V70 VAc 3 8000 2) 40 1.3 2.3 64100 15900 4.0 2.7 1.65 2.1 4.7 87600 32200 2.7 1.64 2.9 8.4 114600 57700 2.0 1.90 DMAA 8100 3) 3.9 16.1 127100 112500 1.1 2.13 4.4 19.9 145000 138800 1.0 1.90 Implementation Example 20 Methyl cinnamate V70 VAc 1 8000 2) 40 0.9 1.6 42200 11300 3.7 1.8 1.82 2.0 4.0 55200 27700 2.0 1.93 2.9 7.4 74400 51000 1.5 2.16 MAn 8100 3) 3.9 13.0 90500 90900 1.0 2.42 4.4 13.2 97200 92300 1.1 2.37 5.4 18.1 100800 126400 0.8 2.56 Example 21 trans-cinnamic acid V70 VAc 1 8000 50 1.5 3.9 86800 26800 3.2 3.0 1.85 2.5 9.5 132800 65300 2.0 2.14 3.0 12.7 166900 87100 1.9 2.38 3.8 21.7 226400 149300 1.5 2.57 Example 22 Methyl cinnamate V70 VAc 10 1000 45 1.7 5.1 7300 4500 1.6 1.6 1.55 2.7 12.0 11100 10300 1.1 2.07 3.2 17.7 16000 15300 1.0 2.35 3.5 20.7 17400 17900 1.0 2.74 1) Internal pressure: 9 bar 2) The calculated value used for Mn / theoretical Mn (conversion rate 5%) 3) The molar ratio (Y / A) is obtained using the total amount of added organic compound (A) and the total amount of organic compound (A).

[0158] In Examples 1-20, the ratio (Mn / theoretical Mn) was below 10.0 at the beginning of polymerization, and Mn increased with the increase of conversion rate, thus confirming that polymerization was carried out in a controllable manner.

[0159] In Examples 1-11 and 15-20, the ratio (Mn / theoretical Mn) was below 5.0 at the beginning of polymerization, and Mn increased with the increase of conversion rate, thus confirming that polymerization was carried out in a more controllable manner.

[0160] In Examples 21-22, it was confirmed that the obtained polymers had the structure shown in Formula (V) or (VI) at their ends. The molar ratio (F) of the structure shown in Formula (V) or (VI) relative to the amount at the polymer ends was close to 1, thus confirming that the polymers quantitatively had the structure shown in Formula (V) or (VI) relative to their ends.

[0161] In Comparative Example 1, the value of Mn / theoretical Mn at the initial stage of polymerization exceeded 10.0, confirming a lack of polymerization control.

[0162] In Comparative Example 2, the lack of polymerization control was confirmed because Mn did not increase with the increase in conversion rate.

[0163] In Comparative Example 3, the lack of productivity was confirmed due to the extremely slow polymerization process.

[0164] none

Claims

1. A method for manufacturing a polymer, comprising a polymerization step in which a monomer (Y) is subjected to controlled free radical polymerization in the presence of an organic compound (A) as shown in formula (I) and a free radical generator (B) to obtain a polymer; wherein the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20, and the polymerization temperature is 0 to 80°C; [In formula (I), R1 is an alkenyl or aryl group, and R2 is a group as shown in formula (II) or (III) below, and R1 and R2 may also be linked together to form a ring]; [In formula (II), R3 is a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkenyl group, an alkoxy group, an amino group, a nitro group, a cyano group, an acetyl group, a trifluoromethyl group, or a hydroxyl group, and * indicates a bonding bond]; [In formula (III), R3 is synonymous with the above formula (II), and * indicates a bonding bond].

2. A method for manufacturing the polymer as claimed in claim 1, wherein R1 is an aryl group.

3. A method for manufacturing the polymer as claimed in claim 1 or 2, wherein the organic compound (A) is of type E.

4. A method for manufacturing the polymer of claim 3, wherein the organic compound (A) is represented by the following formula (IV); [in formula (IV), R3 is synonymous with formula (II) above, and R4 is a hydrogen atom, alkyl, alkoxy or hydroxyl group].

5. A method for manufacturing the polymer as claimed in claim 4, wherein R4 is a hydrogen atom.

6. A method for manufacturing the polymer as claimed in claim 1 or 2, wherein R3 is a methoxy or hydroxyl group.

7. A method for manufacturing the polymer as claimed in claim 1 or 2, wherein the molar ratio (Y / A) of the monomer (Y) to the organic compound (A) is 300 to 30000.

8. A method for manufacturing the polymer of claim 1 or 2, wherein the monomer (Y) comprises an olefin, ethylene ester, acrylic acid, acrylate, acrylamide monomer, styrene monomer, N-vinylamide monomer or dicarboxylic acid monomer.

9. A method for manufacturing the polymer of claim 8, comprising a polymerization step in which controlled free radical polymerization of ethylene ester is carried out in the presence of an organic compound (A) and a free radical generator (B) to obtain an ethylene ester-based polymer; and a saponification step in which the obtained ethylene ester-based polymer is saponified to obtain an ethylene alcohol-based polymer.

10. A method for manufacturing the polymer of claim 8, comprising a polymerization step in which controlled free radical polymerization of ethylene ester and controlled free radical polymerization of ethylene ester and monomers other than ethylene ester are carried out sequentially in the presence of an organic compound (A) and a free radical generator (B) to obtain an ethylene ester-based block copolymer.

11. A method for manufacturing the polymer of claim 10, comprising a polymerization step in which controlled free radical polymerization of ethylene ester and controlled free radical polymerization of ethylene ester and monomers other than ethylene ester are carried out sequentially in the presence of an organic compound (A) and a free radical generator (B) to obtain an ethylene ester-based block copolymer; and a saponification step in which the obtained ethylene ester-based block copolymer is saponified to obtain an ethylene alcohol-based block copolymer.

12. A composition for free radical polymerization comprising an organic compound (A) of formula (I), a free radical generator (B), and a monomer (Y), wherein the molar ratio (B / A) of (B) relative to (A) is 0.5 to 20, the molar ratio (Y / A) of monomer (Y) relative to organic compound (A) is 300 to 30000, and monomer (Y) contains vinyl ester or N-vinylpyrrolidone; [In formula (I), R1 is alkenyl or aryl, R2 is a group of formula (II) or (III) below, and R1 and R2 may also be linked to each other to form a ring]; [In formula (II), R3 is a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl, or hydroxyl, * indicates a bonding bond]; [In formula (III), R3 is synonymous with the above formula (II), * indicates a bonding bond].

13. A composition for free radical polymerization as claimed in claim 12, wherein the monomer (Y) contains ethylene ester.

14. A free radical polymerization control agent comprising an organic compound (A) of formula (IV) below (wherein, (Does not contain cinnamaldehyde or cinnamate); [In formula (IV), R3 refers to hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl or hydroxyl, and R4 refers to hydrogen atom, alkyl, alkoxy or hydroxyl].

15. A polymer containing vinyl ester units or N-vinylpyrrolidone units and having a terminal structure as shown in formula (V) or (VI); [in formula (V), R1 is an alkenyl or aryl group, R2 is a group as shown in formula (II) or (III) below, R1 and R2 may also be linked to form a ring, * indicates a bonding bond]; [in formula (VI), R1 and R2 are synonyms of formula (V) above, * indicates a bonding bond]; [in formula (II), R3 is a hydrogen atom, halogen atom, alkyl, aryl, alkenyl, alkoxy, amino, nitro, cyano, acetyl, trifluoromethyl or hydroxyl group, * indicates a bonding bond]; [in formula (III), R3 is synonyms of formula (II) above, * indicates a bonding bond].

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