Polysiloxane resin and its use

Abstract

To provide a polysiloxane resin that can give a cured product having excellent flexibility and weather resistance.SOLUTION: A polysiloxane resin contains a constitutional unit (a) derived from a specific silane compound (A), and a constitutional unit (b) derived from a polymer (B) having hydrolyzable silyl groups at both terminals.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polysiloxane resin and its use. [Background technology]

[0002] Polysiloxane resins (polysiloxane resins) grafted with organic materials such as acrylic, which have inorganic properties, are attracting industrial attention due to their interesting properties as inorganic-organic hybrid resins.

[0003] Polysiloxane resins are known to produce cured products (coating films) that exhibit high durability, and are used in a wide range of applications, including coating agents, construction sealants, adhesives, paints, etc. In particular, in the field of paints, water-based paints containing polysiloxane resins are becoming increasingly popular in the market due to their minimal adverse effects on the human body and the environment, and there is growing demand for them in a variety of applications.

[0004] As such a polysiloxane-based resin, Patent Document 1 discloses a polysiloxane-based resin containing polysiloxane and acrylic silicone. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2017 / 169459 Summary of the Invention [Problem to be solved by the invention]

[0006] Although the above-mentioned techniques are excellent, there is room for further improvement in terms of flexibility and weather resistance of the cured product (cured film) obtained by curing the polysiloxane resin.

[0007] Therefore, an object of one aspect of the present invention is to provide a polysiloxane-based resin that can provide a cured product that is excellent in flexibility and weather resistance. [Means for solving the problem]

[0008] As a result of extensive research to solve the above problems, the present inventors discovered for the first time that a cured product having excellent flexibility and weather resistance can be provided by using a polysiloxane resin containing a structural unit derived from a silane compound and a structural unit derived from a polymer having hydrolyzable silyl groups at both ends, and this discovery led to the completion of the present invention.

[0009] Therefore, one aspect of the present invention is a compound represented by the following general formula (I): R 1 n -Si-(OR 2 ) 4-n (I) (In the formula, R 1 are each independently an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3. The polysiloxane resin comprises a structural unit (a) derived from a silane compound (A) represented by the formula: [Effects of the Invention]

[0010] According to one aspect of the present invention, it is possible to provide a polysiloxane-based resin that can provide a cured product that is excellent in flexibility and weather resistance. DETAILED DESCRIPTION OF THE INVENTION

[0011] An embodiment of the present invention will be described in detail below. In this specification, unless otherwise specified, "A to B" representing a numerical range means "A or more and B or less." In addition, in this specification, "(meth)acrylic" means "acrylic" and / or "methacrylic." Furthermore, all documents described in this specification are incorporated herein by reference.

[0012] 1. Overview of the Invention The cured product (cured film) obtained by curing polysiloxane resin exhibits high durability due to the high bond energy derived from the siloxane bond. However, the cured product tends to have low flexibility, which can lead to problems such as cracking.

[0013] As a method for improving the flexibility of a cured product obtained by curing a polysiloxane resin and suppressing the occurrence of cracks, a method has been proposed in which a (meth)acrylic monomer is grafted onto the polysiloxane resin to improve the elasticity of the resulting cured product. In this method, in order to suppress the occurrence of cracks, it is necessary to graft a large amount of (meth)acrylic monomer onto the polysiloxane resin. However, the present inventors have found that when a polysiloxane resin grafted with such a large amount of (meth)acrylic monomer is cured, the weather resistance of the resulting cured product is reduced. In other words, the prior art may not be able to achieve both the excellent flexibility and weather resistance of a polysiloxane resin.

[0014] In light of these circumstances, the present inventors have conducted extensive research aimed at providing a polysiloxane-based resin capable of providing a cured product having excellent flexibility and weather resistance. As a result, they have discovered that a polysiloxane-based resin containing structural units derived from a specific silane compound and structural units derived from a polymer having hydrolyzable silyl groups at both ends can improve the flexibility of the resulting cured product without grafting a large amount of (meth)acrylic monomer (i.e., even when a small amount of (meth)acrylic monomer is grafted or when no (meth)acrylic monomer is grafted), thereby providing a cured product having excellent flexibility and weather resistance. This discovery led to the completion of the present invention. Furthermore, they have also discovered that such a polysiloxane-based resin has excellent storage stability.

[0015] As described above, conventional polysiloxane-based resins have been unable to provide a cured product that is both flexible and weather-resistant. Given these circumstances, the discovery of a polysiloxane-based resin (a polysiloxane-based resin according to one embodiment of the present invention) that can provide a cured product that is excellent in both flexibility and weather resistance can be considered a surprising discovery. Furthermore, such polysiloxane-based resins are extremely useful, particularly in the field of paints.

[0016] Furthermore, even when the polysiloxane resin according to one embodiment of the present invention is made into an aqueous solution (a solution or dispersion in an aqueous medium) in which the polysiloxane resin is uniformly dispersed or soluble in water, it can provide a cured product (cured film) that is excellent in both flexibility and weather resistance. For this reason, the polysiloxane resin according to one embodiment of the present invention is also extremely useful as an aqueous coating material.

[0017] Furthermore, aqueous solutions in which such polysiloxane resins are uniformly dispersed or soluble in water have minimal adverse effects on the human body and the environment, and can therefore contribute to the achievement of Sustainable Development Goals (SDGs), such as Goal 12, "Ensure sustainable consumption and production patterns."

[0018] [2. Polysiloxane Resin] A polysiloxane-based resin according to one embodiment of the present invention is a polysiloxane-based resin that includes a structural unit (a) (hereinafter, sometimes referred to as "structural unit (a)") derived from a silane compound (A), and a structural unit (b) (hereinafter, sometimes referred to as "structural unit (b)") derived from a polymer (B) (hereinafter, sometimes referred to as "polymer (B)") that has hydrolyzable silyl groups at both ends.

[0019] In this specification, "a polysiloxane-based resin according to one embodiment of the present invention, comprising a structural unit (a) derived from a silane compound (A) and a structural unit (b) derived from a polymer (B) having hydrolyzable silyl groups at both ends" may be referred to as "the present polysiloxane-based resin."

[0020] The polysiloxane resin has the above-described structure, which provides a cured product having excellent flexibility and weather resistance. The polysiloxane resin also has excellent storage stability.

[0021] In one embodiment of the present invention, the polysiloxane resin may contain, in addition to the above-mentioned structural unit (a) and structural unit (b), a structural unit (c) derived from a silane compound (C) and a structural unit (d) derived from a monomer (D).

[0022] This polysiloxane resin can also be said to be a graft-polymerized polysiloxane resin obtained by grafting a monomer (D) onto a polysiloxane resin obtained by condensing a silane compound (A), a polymer (B), and optionally a silane compound (C).

[0023] <Structural unit (a) derived from silane compound (A)> The present polysiloxane resin contains a structural unit (a) derived from a silane compound (A).

[0024] (Silane compound (A)) The silane compound (A) is a compound having a hydrolyzable silyl group represented by the following general formula (I): R1 n -Si-(OR 2 ) 4-n (I) (In the formula, R 1 are each independently a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or an unsubstituted or substituted aryl group, and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3. The silane compound (A), together with the polymer (B) described below, is a main component constituting the polysiloxane chain, which is the main chain of the polysiloxane resin. The silane compound (A) can also be said to be a silane compound represented by the general formula (I) above, which has a hydrolyzable silyl group but does not have a radically polymerizable unsaturated group.

[0025] R in general formula (I) 1 Specific examples of the alkyl group in the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an amyl group, an isoamyl group, a hexyl group, a cyclohexyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a heptyl group, an isoheptyl group, an n-octyl group, an isooctyl group, and a 2-ethylhexyl group.

[0026] R in general formula (I) 1 Specific examples of the aryl group in include a phenyl group, a naphthyl group, and a benzyl group.

[0027] R in general formula (I) 2 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, and a decyl group.

[0028] Specific compounds represented by general formula (I) include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltriisopropoxysilane, butyltrimethoxysilane, butyltriethoxysilane, butyltriisopropoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, hexyltriisopropoxysilane, octyltrimethoxysilane, and octyltriethoxysilane. , octyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, dimethyldimethoxysilane, diphenyldimethoxysilane, trimethylmonomethoxysilane, triphenylmonomethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, and the like.

[0029] In general formula (I), n may be an integer of 0 to 3, but it is particularly preferred that n is 1. That is, the silane compound (A) is preferably a trialkoxysilane compound. When n is 1, there are three crosslinkable hydrolyzable silyl groups, making it possible to form a polymer with a network structure. Specific examples of compounds in which n is 1 are methyltrimethoxysilane, phenyltrimethoxysilane, etc., which are preferred from the viewpoint of availability.

[0030] From the viewpoint of facilitating condensation of the silane compound (A) with the polymer (B) having hydrolyzable silyl groups at both ends, R 2 The alkyl group preferably has 1 to 3 carbon atoms, and most preferably 1 carbon atom.

[0031] The amount of structural unit (a) in the polysiloxane resin is preferably 10 to 90% by weight, more preferably 20 to 80% by weight, and even more preferably 30 to 70% by weight, based on 100% by weight of the total amount of the polysiloxane resin. When the amount of structural unit (a) is 10 to 90% by weight, based on 100% by weight of the total amount of the polysiloxane resin, the durability and weather resistance of the resulting cured product are improved.

[0032] <Structural Unit (b) Derived from Polymer (B) Having Hydrolyzable Silyl Groups at Both Terminals> This polysiloxane resin contains a structural unit (b) derived from a polymer (B) having hydrolyzable silyl groups at both ends. Hereinafter, the "polymer (B) having reactive silyl groups at both ends" may be simply referred to as the "polymer (B)."

[0033] (Polymer (B) having hydrolyzable silyl groups at both ends) The polymer (B) according to one embodiment of the present invention is a polymer containing reactive silyl groups at both ends and a polymer (molecular chain) that is a main chain (main chain skeleton). The polymer (B) can also be said to be a telechelic oligomer.

[0034] (reactive silyl group) Examples of the reactive silyl groups present at both ends of the polymer (B) include groups represented by the following general formula (II): -[Si(R 3 ) 2-b (Y) b O] m -Si(R 4 ) 3-a (Y) a (II) {where, R 3 , R 4each represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a triorganosiloxy group represented by (R')3SiO- (R' represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the three R's may be the same or different), and R 3 or R 4 When two or more Y's are present, they may be the same or different. Y represents a hydroxyl group or a hydrolyzable group, and when two or more Y's are present, they may be the same or different. a represents 0, 1, 2, or 3, and b represents 0, 1, or 2. m is an integer from 0 to 19, provided that a+mb≧1 is satisfied.}

[0035] Examples of the hydrolyzable group include commonly used groups such as a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amido group, an aminooxy group, a mercapto group, an alkenyloxy group, etc. Among these, the alkoxy group, the amido group, and the aminooxy group are preferred, and the alkoxy group is particularly preferred because it is mildly hydrolyzable and easy to handle.

[0036] More specific examples of the reactive silyl group represented by general formula (II) include a methyldimethoxysilyl group, a trimethoxysilyl group, a methyldiethoxysilyl group, a triethoxysilyl group, and a triisopropoxysilyl group.

[0037] The reactive silyl groups present at both ends of the polymer (B) may be the same or different, but in order to disentangle the entanglements between molecular chains, it is preferable that the free chain ends are uniformly present throughout the entire crosslinked structure, and therefore it is preferable that there is no significant difference in reactivity.

[0038] The polymer (B) may have reactive silyl groups only at both ends, or may have reactive silyl groups in the main chain in addition to both ends. The polymer (B) has an average of more than 1.0 reactive silyl group per molecule, more preferably 1.5 to 3.0, and even more preferably 1.8 to 2.5.

[0039] (main chain) The main chain of the polymer (B) is not particularly limited, but is preferably at least one selected from the group consisting of polyalkylene oxide polymers, poly(meth)acrylic polymers, and polyisobutylene polymers, as this has the advantage of being easy to synthesize, and is more preferably a poly(meth)acrylic polymer, as this has the advantage of providing a cured product with excellent weather resistance.

[0040] (Polyalkylene oxide polymer) In one embodiment of the present invention, the main chain of the polymer (B) may be a polyalkylene oxide polymer. Examples of the main structural unit (alkylene oxide monomer unit) of the polyalkylene oxide polymer include ethylene oxide and propylene oxide.

[0041] In one embodiment of the present invention, the polyalkylene oxide polymer may be a polymer obtained by copolymerizing or even block copolymerizing an alkylene oxide monomer with another conventionally known monomer. When the polyalkylene oxide polymer contains another conventionally known monomer in addition to the alkylene oxide monomer, it is preferable that the polyalkylene oxide polymer contains 40% by weight or more of structural units derived from the alkylene oxide monomer in 100% by weight of the total amount of the polyalkylene oxide polymer.

[0042] (Poly(meth)acrylic polymer) In one embodiment of the present invention, the main chain of the polymer (B) is preferably a poly(meth)acrylic polymer. Various types of main structural units ((meth)acrylic monomer units) of the poly(meth)acrylic polymer can be used. Examples include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate. (meth)acrylic acid-based monomers such as dodecyl (meth)acrylate, phenyl (meth)acrylate, toluyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, stearyl (meth)acrylate, glycidyl (meth)acrylate, 2-aminoethyl (meth)acrylate, γ-(methacryloyloxypropyl)trimethoxysilane, and ethylene oxide adducts of (meth)acrylic acid.

[0043] These (meth)acrylic acid monomers may be used alone or in combination. Among them, from the viewpoint of the physical properties of the resulting poly(meth)acrylic polymer, (meth)acrylic acid ester monomers are preferred, acrylic acid ester monomers are more preferred, and (meth)acrylic acid alkyl ester monomers having an alkyl group ester-bonded to (meth)acrylic acid are particularly preferred. More specifically, the (meth)acrylic acid alkyl ester monomers include (meth)acrylic acid alkyl ester monomers having an alkyl group, such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, and isopropoxyethyl (meth)acrylate, wherein the alkyl group has an alkoxy group having 1 to 5 carbon atoms; (meth)acrylic acid alkyl ester monomers having an alkyl group having 1 to 5 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, and tert-butyl (meth)acrylate; (meth)acrylic acid alkyl ester monomers having an alkyl group having 1 to 5 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, and tert-butyl (meth)acrylate; (meth)acrylic acid alkyl ester monomers having an alkyl group carbon number of 6 to 15, such as n-hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, and tetradecyl (meth)acrylate; and (meth)acrylic acid alkyl ester monomers having an alkyl group carbon number of 16 to 25, such as pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, eicosyl (meth)acrylate, and docosyl (meth)acrylate.

[0044] In one embodiment of the present invention, the poly(meth)acrylic polymer may be a polymer obtained by copolymerizing, or even block copolymerizing, a (meth)acrylic monomer with another conventionally known monomer. When the poly(meth)acrylic polymer contains another conventionally known monomer in addition to the (meth)acrylic monomer, it is preferable that the poly(meth)acrylic polymer contains 40% by weight or more of structural units derived from the (meth)acrylic monomer in 100% by weight of the total amount of the poly(meth)acrylic polymer.

[0045] (Polyisobutylene polymer) In one embodiment of the present invention, the main chain of the polymer (B) may be a polyisobutylene-based polymer. A polyisobutylene-based polymer is a polymer having an isobutylene unit as a main structural unit.

[0046] In one embodiment of the present invention, the polyisobutylene polymer may be a polymer obtained by copolymerizing or even block copolymerizing isobutylene with other conventionally known monomers. When the polyisobutylene polymer contains other conventionally known monomers in addition to isobutylene, it is preferable that the polyisobutylene polymer contains 40% by weight or more of structural units derived from isobutylene, relative to 100% by weight of the total amount of the polyisobutylene polymer.

[0047] (Physical properties of polymer (B)) The glass transition temperature (Tg) of the polymer (B) is not particularly limited, but is preferably 0° C. or lower, more preferably −10° C. or lower, and even more preferably −20° C. or lower. When the Tg of the polymer (B) is 0° C. or lower, a polysiloxane resin with superior flexibility and weather resistance can be obtained. The lower limit of the Tg of the polymer (B) is not particularly limited, but can be, for example, −150° C. or higher.

[0048] The number average molecular weight of the polymer (B) is not particularly limited, but is preferably in the range of 500 to 1,000,000, and more preferably 1,000 to 100,000. The molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is not particularly limited, but is preferably less than 1.8, preferably 1.7 or less, more preferably 1.6 or less, even more preferably 1.5 or less, particularly preferably 1.4 or less, and most preferably 1.3 or less.

[0049] The number-average molecular weight and weight-average molecular weight of the polymer (B) can be determined by gel permeation chromatography (GPC). Typically, chloroform is used as the mobile phase, and the measurement is carried out in a polystyrene gel column. The number-average molecular weight and weight-average molecular weight can be determined in terms of polystyrene.

[0050] (Method for producing polymer (B)) The method for producing polymer (B) is not particularly limited as long as it allows for the introduction of reactive silyl groups to both ends of the polymer main chain. Reactive silyl groups can be introduced to both ends of the main chain by conventionally known methods. However, from the viewpoint of ease of structural control (molecular weight, molecular weight distribution, terminal functionalization rate, etc.), living polymerization methods such as living radical polymerization, living cationic polymerization, and living anionic polymerization are listed. In particular, living radical polymerization is preferred because it allows for the introduction of hydrolyzable silyl groups to both ends with high precision. Examples of living radical polymerization methods include the following: Atom Transfer Radical Polymerization (ATRP) (see J. Am. Chem. Soc. 1995, 117, 5614; Macromolecules. 1995, 28, 1721) ·Sigle Electron Transfer Polymerization; SET-LRP (J. Am. Chem. Soc. 2006, 128, 14156; JPSChem 2007, 45, 1607) Reversible Chain Transfer Catalyzed Polymerization (RTCP) ("Living Radical Polymerization Controlled by Organic Catalysts," Polymer Review, 68, 223-231 (2011); See JP 2014-111798 Reversible addition-fragmentation chain transfer polymerization (RAFT polymerization) Nitroxy radical method (NMP method) Organotellurium Polymerization (TERP) method Polymerization method using organoantimony compounds (SBRP method) Organobismuth polymerization method (BIRP) -Iodine transfer polymerization method.

[0051] More specifically, methods for producing polymer (B) include using an initiator having a reactive silyl group in living radical polymerization to polymerize a main-chain monomer (e.g., a (meth)acrylic monomer), or using an initiator having a functional group convertible to a reactive silyl group to polymerize a main-chain monomer and converting the functional group to a reactive silyl group after polymerization. These methods can produce a polymer with a silyl group introduced at the initiator-derived terminal. It is also possible to convert the growing terminal (preferably a halogen terminal) of the molecular chain (main chain) produced by living radical polymerization into a reactive silyl group. Polymer (B) can be produced by these methods. Conventional methods for producing telechelic polymers can also be used. For example, polymer (B) can be obtained by performing living radical polymerization using a bifunctional initiator and converting both growing terminals (preferably a halogen terminal) to reactive silyl groups using a conventional method.

[0052] The amount of structural unit (b) in the polysiloxane resin is preferably 1 to 10% by weight, and more preferably 3 to 7% by weight, based on 100% by weight of the total amount of the polysiloxane resin. When the amount of structural unit (b) is 1 to 10% by weight, based on 100% by weight of the total amount of the polysiloxane resin, the durability and weather resistance of the resulting cured product are improved.

[0053] When the present polysiloxane-based resin is a polysiloxane-based resin composed of the structural unit (a) and the structural unit (b) (i.e., when it does not contain the structural unit (c) and the structural unit (d) described below), the amount of each component in the present polysiloxane-based resin, where the total amount of the structural unit (a) and the structural unit (b) is taken as 100% by weight, is preferably 90 to 99% by weight for the structural unit (a) and 1 to 10% by weight for the structural unit (b), and more preferably 93 to 97% by weight for the structural unit (a) and 3 to 7% by weight for the structural unit (b).

[0054] <Structural unit (c) derived from silane compound (C)> The present polysiloxane resin preferably contains a structural unit (c) derived from a silane compound (C) (hereinafter, sometimes referred to as "structural unit (c)").

[0055] (Silane Compound (C)) The silane compound (C) is a silane compound having a radical polymerizable unsaturated group and a hydrolyzable silyl group. In one embodiment of the present invention, the silane compound (C) is a compound having a hydrolyzable silyl group represented by the following general formula (III): R 5 c R 6 d -Si-(OR 7 ) 4-c-d (III) (In the formula, R 5 is a substituted alkyl group or alkenyl group having 1 to 10 carbon atoms and having a polymerizable unsaturated group, or an aryl group having a polymerizable unsaturated group and optionally having other substituents, and R 6are each independently an unsubstituted or substituted alkyl group having 1 to 10 carbon atoms, or an unsubstituted or substituted aryl group, and R 7 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and c+d is an integer of 1 to 3. In the above general formula (III), R 5 and R 6 is a group that bonds directly to Si (silicon).

[0056] In general formula (III), c is an integer of 1 to 3, d is an integer of 0 to 2, and c+d may be an integer of 1 to 3, but it is preferable that c is 1 and d is 0 or 1, and it is particularly preferable that c is 1 and d is 0. That is, the silane compound (C) is preferably a trialkoxysilane compound.

[0057] R in general formula (III) 5 is a substituted alkyl group having 1 to 10 carbon atoms and having a radically polymerizable unsaturated group, an alkenyl group, or an unsubstituted or substituted aryl group having a radically polymerizable unsaturated group. The radically polymerizable unsaturated group is not particularly limited, but examples thereof include a vinyl group, a (meth)acryloyl group, and a (meth)acrylamide group. From the viewpoints of high reactivity and versatility, a vinyl group or a (meth)acryloyl group is preferred.

[0058] R 5is an alkyl group having a radical polymerizable unsaturated group, examples of the silane compound (C) include (meth)acryloxymethyltrimethoxysilane, (meth)acryloxymethylmethyldimethoxysilane, (meth)acryloxymethyldimethylmethoxysilane, (meth)acryloxymethyltriethoxysilane, (meth)acryloxymethylmethyldiethoxysilane, (meth)acryloxymethyldimethylethoxysilane, 2-(meth)acryloxyethyltrimethoxysilane, 2-(meth)acryloxyethylmethyldimethoxysilane, 2- (Meth)acryloxyethyl dimethyl methoxy silane, 2-(meth)acryloxyethyl triethoxy silane, 2-(meth)acryloxyethyl methyl diethoxy silane, 2-(meth)acryloxyethyl dimethyl ethoxy silane, γ-(meth)acryloxypropyl trimethoxy silane, γ-(meth)acryloxypropyl methyl dimethoxy silane, γ-(meth)acryloxypropyl dimethyl methoxy silane, γ-(meth)acryloxypropyl triethoxy silane, γ-(meth)acryloxypropyl methyl diethoxy silane, γ- (Meth)acryloxypropyldimethylethoxysilane, 4-(meth)acryloxybutyltrimethoxysilane, 4-(meth)acryloxybutylmethyldimethoxysilane, 4-(meth)acryloxybutyldimethylmethoxysilane, 4-(meth)acryloxybutyltriethoxysilane, 4-(meth)acryloxybutylmethyldiethoxysilane, 4-(meth)acryloxybutyldimethylethoxysilane, 5-(meth)acryloxypentyltrimethoxysilane, 5-(meth)acryloxypentylmethyldimethoxysilane, 5-(meth)acryloxypentylmethyldimethoxysilane p) acryloxypentyldimethylmethoxysilane, 5-(meth)acryloxypentyltriethoxysilane, 5-(meth)acryloxypentylmethyldiethoxysilane, 5-(meth)acryloxypentyldimethylethoxysilane, 6-(meth)acryloxyhexyltrimethoxysilane, 6-(meth)acryloxyhexylmethyldimethoxysilane, 6-(meth)acryloxyhexyldimethylmethoxysilane, 6-(meth)acryloxyhexyltriethoxysilane, 6-(meth)acryloxyhexylmethyldiethoxysilane,6-(meth)acryloxyhexyldimethylethoxysilane, etc.

[0059] R 5 Examples of the silane compound (C) in which is an alkenyl group include vinyltrimethoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinyltriethoxysilane, vinylmethyldiethoxysilane, and vinyldimethylethoxysilane.

[0060] R 5 is an aryl group having a polymerizable unsaturated group and optionally having other substituents, examples of the silane compound (C) include p-styryltrimethoxysilane, p-styrylmethyldimethoxysilane, p-styryldimethylmethoxysilane, p-styryltriethoxysilane, p-styrylmethyldiethoxysilane, and p-styryldimethylethoxysilane.

[0061] Among these, R 5 As the alkyl group, a (meth)acryloyl group-substituted alkyl group or a vinyl group-substituted alkyl group is preferred.

[0062] R in general formula (III) 6 are each independently an unsubstituted or substituted alkyl group having 1 to 10 carbon atoms, or an unsubstituted or substituted aryl group.

[0063] R in general formula (III) 6 Specific examples of the alkyl group in the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an amyl group, an isoamyl group, a hexyl group, a cyclohexyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a heptyl group, an isoheptyl group, an n-octyl group, an isooctyl group, and a 2-ethylhexyl group.

[0064] R in general formula (III) 6 Specific examples of the aryl group in include a phenyl group, a naphthyl group, and a benzyl group.

[0065] R in general formula (III) 6 When c is 1 and d is 1, it is preferably a methyl group.

[0066] R in general formula (III) 7 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, and a decyl group.

[0067] From the viewpoint of facilitating condensation of the silane compound (C) with the silane compound (A) and the polymer (B), R 7 The number of carbon atoms in the alkyl group is preferably 1 to 3, and most preferably 1. In particular, 7 When c is 1 and d is 1, it is preferably a methyl group.

[0068] The number average molecular weight of the co-condensate (co-condensate) obtained by dehydration condensation of the silane compound (A) and the polymer (B) with the silane compound (C) is not particularly limited, but is preferably in the range of 500 to 100,000, more preferably 1,000 to 10,000.

[0069] Here, the number average molecular weight of the condensate is determined by gel permeation chromatography (GPC). Typically, chloroform is used as the mobile phase, and the measurement is carried out in a polystyrene gel column, and the number average molecular weight can be determined in terms of polystyrene.

[0070] When the polysiloxane resin contains the structural unit (c), the amount of the structural unit (c) in the polysiloxane resin is preferably 1 to 10% by weight, more preferably 1.5 to 8% by weight, and even more preferably 2 to 6% by weight, based on 100% by weight of the total amount of the polysiloxane resin. When the amount of the structural unit (c) is 1 to 10% by weight, based on 100% by weight of the total amount of the polysiloxane resin, there is an advantage in that gelation is less likely to occur when graft chains derived from the monomer (D) are formed.

[0071] <Structural unit (d) derived from monomer (D)> The present polysiloxane resin preferably contains a structural unit (d) derived from the monomer (D) (hereinafter, sometimes referred to as "structural unit (d)").

[0072] (Monomer (D)) The monomer (D) has a radically polymerizable unsaturated group but does not have a hydrolyzable silyl group. The radically polymerizable unsaturated group in the monomer (D) undergoes radical polymerization with the radically polymerizable unsaturated group derived from the silane compound (C), forming a graft chain derived from the monomer (D) on a condensate obtained by dehydration condensation of the silane compound (A) and the polymer (B) with the silane compound (C).

[0073] Monomer (D) is not particularly limited as long as it is a monomer that has a radically polymerizable unsaturated group but does not have a hydrolyzable silyl group, but examples include monomers having a salt structure consisting of an acid and a base, (meth)acrylic acid alkyl esters, and other monomers, as shown below. One of these monomers may be used alone, or two or more may be used in combination. Among these, it is preferable that monomer (D) contains a monomer having a salt structure consisting of an acid and a base, since this has the advantage of being able to prepare an aqueous solution in which the polysiloxane resin is uniformly dispersed or soluble in water.

[0074] (a monomer having a salt structure consisting of an acid and a base) In the monomer having a salt structure consisting of an acid and a base according to one embodiment of the present invention, the salt structure may be, for example, a neutral salt structure between a strong acid and a strong base, a neutral salt structure between a strong acid and a weak base, a neutral salt structure between a weak acid and a strong base, or a neutral salt structure between a weak acid and a weak base. More specific salt structures include, for example, sodium sulfonate, potassium sulfonate, calcium sulfonate, sodium nitrate, potassium nitrate, calcium nitrate, etc. (neutral salt structures between a strong acid and a strong base), ammonium sulfonate, ammonium nitrate, etc. (neutral salt structures between a strong acid and a weak base), sodium acetate, potassium acetate, calcium acetate, sodium phosphate, potassium phosphate, calcium phosphate, etc. (neutral salt structures between a weak acid and a strong base), ammonium acetate, ammonium phosphate, etc. (neutral salt structures between a weak acid and a weak base). In one embodiment of the present invention, the salt structure is preferably sodium sulfonate or ammonium sulfonate. In this specification, the term "monomer having a salt structure consisting of an acid and a base" can also be said to be "a monomer having a radically polymerizable unsaturated group, not having a hydrolyzable silyl group, and having a salt structure consisting of an acid and a base."

[0075] More specifically, examples of the monomer having a salt structure consisting of an acid and a base include ADEKA REASOAP SR-05, SR-10, SR-20, SR-1025, SR-2025, SR-3025, SR-10S, NE-10, NE-20, NE-30, NE-40, SE-10, SE-20, ER-10, ER-20, ER-30, and ER-40 manufactured by ADEKA CORPORATION; and Antox-MS-60, RMA-1120, RMA-564, RMA-568, RMA-506, and MA-30 manufactured by Nippon Nyukazai Co., Ltd. MA-50, MA-100, MA-150, RMA-1120, MPG130-MA, MPG-130MA, RMA-150M, RMA-300M, RMA-450M, RA-1020, RA-1820, Aqualon KH-05, KH-10, RN-20, RN-30, RN-50, RN-2025, HS-10, HS-20, HS-1025, BC05, BC10, BC0515, BC1025 manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Eleminol JS-2, JS-20, RS manufactured by Sanyo Chemical Industries, Ltd. -30, Kao Corporation's Latemul S-180, S-180A, PD-104, PD-420, PD-430, sodium sulfoethyl methacrylate, sodium acrylamido-t-butylsulfonate, sodium 2-(methacryloyloxy)ethanesulfonate, sodium acrylamido-t-butylsulfonate, potassium 2-(methacryloyloxy)ethanesulfonate, potassium acrylamido-t-butylsulfonate, calcium 2-(methacryloyloxy)ethanesulfonate, calcium acrylamido-t-butylsulfonate, ammonium sulfoethyl methacrylate, ammonium acrylamido-t-butylsulfonate, ammonium 2-(methacryloyloxy)ethanesulfonate, ammonium acrylamido-t-butylsulfonate, sodium acrylate, potassium acrylate, calcium acrylate, ammonium acrylate, sodium methacrylate, potassium methacrylate, calcium methacrylate, ammonium methacrylate, and the like.

[0076] ((Meth)acrylic acid alkyl ester) In one embodiment of the present invention, the (meth)acrylic acid alkyl ester is a (meth)acrylic acid ester having an alkyl group having 1 to 18 carbon atoms, and may be a (meth)alkyl monomer that does not contain functional groups such as a hydroxyl group or an epoxy group. In one embodiment of the present invention, the alkyl group in the (meth)acrylic acid alkyl ester may be linear or branched, or may be a cyclic cycloalkyl group. Specific examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, tert-butyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)methacrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate.

[0077] (Monomers other than (meth)acrylic acid alkyl esters) Examples of monomers other than (meth)acrylic acid alkyl esters include nitrile group-containing radically polymerizable monomers such as (meth)acrylonitrile; epoxy group-containing radically polymerizable monomers such as glycidyl (meth)acrylate; hydrophilic radically polymerizable monomers such as 2-hydroxypropyl (meth)acrylate; 2-hydroxypropyl (meth)acrylate; 2-sulfoethyl methacrylate sodium, 2-sulfoethyl methacrylate ammonium, and radically polymerizable monomers having a polyoxyalkylene chain; monomers having two or more polymerizable unsaturated bonds such as polyethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, and allyl (meth)acrylate; and fluorine-containing radically polymerizable monomers such as trifluoro(meth)acrylate, pentafluoro(meth)acrylate, perfluorocyclohexyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, and β-(perfluorooctyl)ethyl (meth)acrylate.

[0078] The radical polymerizable monomer having a polyoxyalkylene chain is not particularly limited, but is preferably an acrylic acid ester or a methacrylic acid ester having a polyoxyalkylene chain. Specific examples thereof include Blenmar PE-90, PE-200, PE-350, AE-90, AE-200, AE-350, PP-500, PP-800, PP-1000, AP-400, AP-550, AP-800, 700PEP-350B, 10PEP-550B, 55PET-400, 30PET-800, 55PET-800, 30PPT-800, 50PPT-800, 70PPT-800, PME-100, PME-200, PME-400, PME-1000, PME-4000, AME-400, and 50POEP-8 00B, 50AOEP-800B, AEP, AET, APT, PLE, ALE, PSE, ASE, PKE, AKE, PNE, ANE, PNP, ANP, PNEP-600, Kyoeisha Chemical Co., Ltd. Light Ester 130MA, 041MA, MTG, Light Acrylate EC-A, MTG-A, 130A, DPM-A, P-200A, NP-4EA, NP-8EA, EHDG-A, Nippon Nyukazai Co., Ltd. MA-30, MA-50, MA-100, MA-150, RMA-1120, RMA-564, RMA-568, RMA-506, MPG130-MA, Antox Examples include MS-60, MPG-130MA, RMA-150M, RMA-300M, RMA-450M, RA-1020, RA-1120, and RA-1820, and NK-ESTER M-20G, M-40G, M-90G, M-230G, AMP-10G, AMP-20G, AMP-60G, AM-90G, and LA manufactured by Shin-Nakamura Chemical Co., Ltd.

[0079] When the polysiloxane resin contains the structural unit (d), the amount of the structural unit (d) in the polysiloxane resin is preferably 5 to 85% by weight, more preferably 10 to 70% by weight, and even more preferably 30 to 60% by weight, based on 100% by weight of the total amount of the polysiloxane resin. When the amount of the structural unit (a) is 5 to 85% by weight, based on 100% by weight of the total amount of the polysiloxane resin, there is an advantage in that synthesis is simplified.

[0080] (Graft polymerized polysiloxane resin) When the present polysiloxane resin contains the above-mentioned structural unit (c) and structural unit (d), the present polysiloxane resin becomes a polysiloxane resin having graft chains (graft-polymerized polysiloxane resin).

[0081] In this specification, the term "graft-polymerized polysiloxane resin" refers to a structure in which a graft chain is bonded to a co-condensate (a co-condensate obtained by dehydration condensation of a silane compound (A) and a polymer (B) with a silane compound (C)) that is the main chain. The graft-polymerized polysiloxane resin can also be said to be a graft-polymerized co-condensate.

[0082] When the present polysiloxane-based resin is a graft-polymerized polysiloxane-based resin, a cured product with excellent durability can be provided, and therefore the present polysiloxane-based resin is preferably a graft-polymerized polysiloxane-based resin.

[0083] That is, the polysiloxane resin preferably contains, in addition to the silane compound (A) and the polymer (B), a structural unit (c) derived from a silane compound (C) having a radically polymerizable unsaturated group and a hydrolyzable silyl group, and a structural unit (d) derived from a monomer (D) other than the silane compound (A) and the silane compound (C), which has a radically polymerizable unsaturated group but does not have a hydrolyzable silyl group.

[0084] When the present polysiloxane-based resin contains the structural unit (a), the structural unit (b), the structural unit (c), and the structural unit (d), the amount of each component in the present polysiloxane-based resin is, when the total amount of the structural unit (a), the structural unit (b), the structural unit (c), and the structural unit (d) is taken as 100% by weight, the structural unit (a) is 10 to 90% by weight, the structural unit (b) is 1 to 10% by weight, the structural unit (c) is 1 to 10% by weight, and the structural unit (d) is It is preferably 5 to 85% by weight, more preferably 20 to 70% by weight of the structural unit (a), 1.5 to 9% by weight of the structural unit (b), 1.5 to 8% by weight of the structural unit (c), and 10 to 70% by weight of the structural unit (d), and even more preferably 30 to 60% by weight of the structural unit (a), 2 to 8% by weight of the structural unit (b), 2 to 6% by weight of the structural unit (c), and 30 to 60% by weight of the structural unit (d).

[0085] <Method for producing the present polysiloxane resin> The method for producing the polysiloxane resin (hereinafter sometimes referred to as "the production method") is not particularly limited, and the resin can be produced by a known method. However, it is preferable to produce the resin by (i) the method of the following step (1), or (ii) a method including the following step (2) in addition to the following step (1): Step (1): A condensation step of condensing a silane compound (A), a polymer (B), and, if necessary, a silane compound (C); Step (2): A radical polymerization step in which the produced condensate (a condensate containing the structural units (a) to (c)) is radically polymerized with the monomer (D).

[0086] (Process (1)) Step (1) is a step of mixing a silane compound (A), a polymer (B), and, optionally, a silane compound (C) in the presence of water (pure water) and a dehydration condensation catalyst to cause condensation (dehydration condensation). Step (1) can be said to be a step of producing a copolymer of the silane compound (A), the polymer (B), and, optionally, the silane compound (C), and can also be said to be a step of obtaining a condensate containing the structural units (a) to (c). In particular, when step (2) is not performed in the method for producing the present polysiloxane resin (i.e., when the present polysiloxane resin does not contain the structural units (c) and (d)), the condensate produced in step (1) becomes the present polysiloxane resin.

[0087] In one embodiment of the present invention, the number of moles (equivalents) of water (condensation water) added to dehydration-condense the silane compound (A), the polymer (B), and, if necessary, the silane compound (C) is, for example, 0.25 times or more, preferably 0.5 times or more, relative to the total number of moles of the respective components. When the number of moles of water is 0.25 times or more relative to the total number of moles of the respective components, the condensation can be carried out appropriately, and sufficient water resistance, weather resistance, and low tackiness can be expected. The number of moles of water is not particularly limited, but from the viewpoint of storage stability, it is preferably kept to 4.0 times or less relative to the total number of moles of the respective components. In light of these viewpoints, the number of moles of water added in step (1) is preferably 0.25 to 4.0 times, more preferably 0.5 to 3.0 times, and particularly preferably 1.0 to 2.5 times, relative to the total number of moles of the respective components. Normally, when a relatively large amount of water, about twice as much as the original amount, is added, gelation of the solution occurs during condensation, and it tends to be virtually impossible to obtain a condensation product (polysiloxane-based resin). However, the present polysiloxane-based resin can be produced without gelation even when 2.0 times or more water is added, and therefore sufficient condensation can be carried out stably.

[0088] The dehydration condensation catalyst used in step (1) is not particularly limited as long as it is a substance capable of promoting the dehydration condensation reaction of a mixture containing the silane compound (A), the polymer (B), and, if necessary, the silane compound (C), and examples thereof include neutral salt catalysts, acidic catalysts, basic catalysts, etc. Among these, neutral salt catalysts are preferred from the viewpoint of ease of synthesis and storage stability.

[0089] In this specification, the term "neutral salt catalyst" refers to a salt (neutral salt) formed from an acid and a base. Specifically, it is a salt formed by combining a cation selected from the group consisting of Group 1 element ions, Group 2 element ions, tetraalkylammonium ions, and guanidinium ions with an anion selected from the group consisting of Group 17 element ions excluding fluoride ions, sulfate ions, nitrate ions, and perchlorate ions. Examples of neutral salts used as neutral salt catalysts include lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, francium chloride, beryllium chloride, magnesium chloride, calcium chloride, strontium chloride, barium chloride, radium chloride, tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, tetrabutylammonium chloride, tetrapentylammonium chloride, tetrahexylammonium chloride, guanidium chloride; lithium bromide, sodium bromide, potassium bromide, rubidium bromide, cesium bromide, francium bromide, beryllium bromide, magnesium bromide, calcium bromide, strontium bromide, barium bromide, radium bromide, Tetramethylammonium bromide, tetraethylammonium bromide, tetrapropylammonium bromide, tetrabutylammonium bromide, tetrapentylammonium bromide, tetrahexylammonium bromide, guanidium bromide; lithium iodide, sodium iodide, potassium iodide, rubidium iodide, cesium iodide, francium iodide, beryllium iodide, magnesium iodide, calcium iodide, strontium iodide, barium iodide, radium iodide, tetramethylammonium iodide, tetraethylammonium iodide, tetrapropylammonium iodide, tetrabutylammonium iodide, tetrapentylammonium iodide, tetrahexylammonium iodide, guanidium iodide;Lithium sulfate, sodium sulfate, potassium sulfate, rubidium sulfate, cesium sulfate, francium sulfate, beryllium sulfate, magnesium sulfate, calcium sulfate, strontium sulfate, barium sulfate, radium sulfate, tetramethylammonium sulfate, tetraethylammonium sulfate, tetrapropylammonium sulfate, tetrabutylammonium sulfate, tetrapentylammonium sulfate, tetrahexylammonium sulfate, guanidium sulfate; lithium nitrate, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, francium nitrate, beryllium nitrate, magnesium nitrate, calcium nitrate, strontium nitrate, barium nitrate, radium nitrate, tetramethylammonium nitrate, tetraethylammonium nitrate Examples of neutral salts include ammonium nitrate, tetrapropylammonium nitrate, tetrabutylammonium nitrate, tetrapentylammonium nitrate, tetrahexylammonium nitrate, and guanidium nitrate; lithium perchlorate, sodium perchlorate, potassium perchlorate, rubidium perchlorate, cesium perchlorate, francium perchlorate, beryllium perchlorate, magnesium perchlorate, calcium perchlorate, strontium perchlorate, barium perchlorate, radium perchlorate, tetramethylammonium perchlorate, tetraethylammonium perchlorate, tetrapropylammonium perchlorate, tetrabutylammonium perchlorate, tetrapentylammonium perchlorate, tetrahexylammonium perchlorate, and guanidium perchlorate. These neutral salts may be used alone or in combination of two or more.

[0090] As the acidic catalyst, from the viewpoint of compatibility with the silane compound (A), polymer (B), and silane compound (C), or the dilution solvent, an organic acid catalyst is preferred, and a phosphate ester or a carboxylic acid can be suitably used. Specific examples of organic acids include ethyl acid phosphate, butyl acid phosphate, dibutyl pyrophosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid phosphate, isotridecyl acid phosphate, dibutyl phosphate, bis(2-ethylhexyl) phosphate, formic acid, acetic acid, butyric acid, and isobutyric acid. These acidic catalysts may be used alone or in combination of two or more.

[0091] As the basic catalyst, an organic base catalyst is preferred from the viewpoint of compatibility with the silane compound (A), polymer (B), and silane compound (C), or a dilution solvent, and an amine compound can be suitably used. Specific examples of organic bases include triethylamine, diazabicycloundecene, and 1,4-diazabicyclo[2.2.2]octane. These basic catalysts may be used alone or in combination of two or more.

[0092] The amount of the dehydration condensation catalyst is preferably 0.1 ppm to 50,000 ppm, more preferably 1 ppm to 10,000 ppm, particularly preferably 5 ppm to 1,000 ppm, and most preferably 10 ppm to 500 ppm, relative to the total amount of the silane compound (A), polymer (B), and silane compound (C). When the amount of the dehydration condensation catalyst is 0.1 ppm or more, the catalyst functions appropriately. Although a larger amount of the dehydration condensation catalyst can shorten the reaction time, it is often difficult to separate and remove it from the polysiloxane after the reaction is complete. Residual catalyst can reduce the storage stability of the polysiloxane resin obtained by this production method, so from a practical standpoint, the less catalyst used, the better, depending on the production time.

[0093] In step (1), a dilution solvent may be used in addition to the silane compound (A), polymer (B), silane compound (C), water, and dehydration condensation catalyst. Because the silane compound (A), polymer (B), and silane compound (C) are hydrophobic and water is used during the reaction, the dilution solvent is preferably water-soluble. While there is no limit to the amount of dilution solvent, an increase in the amount reduces the concentration of the resulting polysiloxane, which is undesirable from the standpoint of production costs. Specific examples of dilution solvents include methanol, ethanol, 2-propanol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, polyethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, diethylene glycol monoisobutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, ethylene glycol diethyl ether, etc. Among these, methanol, ethanol, and 2-propanol are particularly preferred, considering the possibility of volatilization after production of the polysiloxane resin or during coating film formation.

[0094] (Process (2)) Step (2) is a step of adding the monomer (D) and a radical polymerization initiator to the condensate prepared in step (1) (a condensate containing structural units (a) to (c)). Step (B2) can also be said to be a step of graft-polymerizing the monomer (D) to the condensate prepared in step (1). In other words, by carrying out steps (1) and (2), a graft-polymerized polysiloxane resin (a polysiloxane resin containing structural units (a) to (d)) can be produced.

[0095] The radical polymerization initiator is not particularly limited as long as it is a substance that can initiate a radical polymerization reaction between the radically polymerizable unsaturated group derived from the silane compound (C) and the radically polymerizable unsaturated group derived from the monomer (D) in the condensate prepared in step (1).

[0096] In one embodiment of the present invention, examples of the radical polymerization initiator include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylbutyronitrile), tert-butyl peroxypivalate, tert-butyl peroxybenzoate, tert-butylperoxy-2-ethylhexanoate, di-tert-butyl peroxide, cumene hydroperoxide, and diisopropyl peroxycarbonate.

[0097] In one embodiment of the present invention, the amount of the radical polymerization initiator is, for example, 0.01 to 10% by weight, preferably 0.05 to 7% by weight, and more preferably 0.1 to 5% by weight, relative to the total amount (100% by weight) of the condensate used in step (2). When the amount of the radical polymerization initiator is 0.01% by weight or more, polymerization proceeds appropriately. Furthermore, when the amount of the radical polymerization initiator is 10% by weight or less, a polymer with an appropriate molecular weight can be obtained.

[0098] In step (2), in addition to the monomer (D) and the radical polymerization initiator, any additives may be added within the range in which the effects of the present invention are achieved. Such additives can be appropriately selected by those skilled in the art.

[0099] <Cured product> The polysiloxane resin can be cured by a known method to obtain a cured product, which has excellent flexibility and weather resistance.

[0100] [3. Aqueous Solution Containing the Present Polysiloxane Resin] In one embodiment of the present invention, an aqueous solution containing the present polysiloxane resin (hereinafter, sometimes referred to as the present aqueous solution) is provided. This aqueous solution can also be said to be an aqueous solution in which the present polysiloxane resin is uniformly dispersed or soluble in water.

[0101] In this specification, "a state in which the polysiloxane resin is uniformly dispersed or soluble in water" means that no "precipitation" occurs when an aqueous solution containing the polysiloxane resin is evaluated by the following method: the aqueous solution containing the polysiloxane resin is left to stand at 25°C for one week, and then visually observed to evaluate the appearance of the aqueous solution. If "precipitation" is observed during the above evaluation, the solution does not meet the criteria of "a state in which the polysiloxane resin is uniformly dispersed or soluble in water."

[0102] This aqueous solution can be used as a water-based paint, and furthermore, because it contains this polysiloxane resin, when used as a water-based paint, the resulting coating film (cured product) has the effect of being excellent in flexibility and weather resistance, making this aqueous solution extremely useful in water-based paint applications.

[0103] (Method for producing aqueous solution containing the present polysiloxane-based resin) The aqueous solution can be provided by dispersing, emulsifying, or dissolving the polysiloxane resin in water. That is, in one embodiment of the present invention, there is provided a method for producing an aqueous solution containing a polysiloxane resin, which includes a step of dispersing, emulsifying, or dissolving the polysiloxane resin in water. The step of dispersing, emulsifying, or dissolving the polysiloxane resin in water can also be considered a step of mixing the polysiloxane resin with water.

[0104] [4. Paints containing this polysiloxane resin] In one embodiment of the present invention, a paint containing the present polysiloxane-based resin (hereinafter, sometimes referred to as "the present paint") is provided. Because the present paint contains the present polysiloxane-based resin, it is possible to provide a coating film that is excellent in flexibility and weather resistance, and further, it has excellent storage stability. The present paint is preferably a water-based paint, as this reduces adverse effects on the human body and the environment.

[0105] The present coating material may contain additives commonly used in the art, as long as the effects of the present invention are achieved. Examples of such additives include pigments, fillers, plasticizers, film-forming aids, wetting / dispersing agents, thickeners, antifoaming agents, preservatives, antioxidants, antisettling agents, leveling agents, UV absorbers, antistatic agents, antifreeze agents, antibacterial agents, antifungal agents, tackifiers, and rust inhibitors. Only one type of additive may be contained, or two or more types may be contained. The amount of these additives can be appropriately determined by one skilled in the art depending on the intended use.

[0106] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0107] That is, one aspect of the present invention includes the following. <1> The following general formula (I): R 1 n -Si-(OR 2 ) 4-n (I) (In the formula, R 1 are each independently an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, and R 2are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3. A polysiloxane resin comprising a structural unit (a) derived from a silane compound (A) represented by the formula: <2> the main chain of the polymer (B) is at least one selected from the group consisting of a polyalkylene oxide polymer, a poly(meth)acrylic polymer, and a polyisobutylene polymer; <1> The polysiloxane resin according to claim 1. <3> The composition further comprises a structural unit (c) derived from a silane compound (C) having a radical polymerizable unsaturated group and a hydrolyzable silyl group, and a structural unit (d) derived from a monomer (D) having a radical polymerizable unsaturated group and no hydrolyzable silyl group. <1> or <2> The polysiloxane resin according to claim 1. <4> The monomer (D) includes a monomer having a salt structure formed from an acid and a base. <3> The polysiloxane resin according to claim 1. <5> When the total amount of the structural units (a), (b), (c), and (d) is taken as 100% by weight, the structural unit (a) accounts for 10 to 90% by weight, the structural unit (b) accounts for 1 to 10% by weight, the structural unit (c) accounts for 1 to 10% by weight, and the structural unit (d) accounts for 5 to 85% by weight. <3> or <4> The polysiloxane resin according to claim 1. <6> <1> ~ <5> 1. An aqueous solution containing the polysiloxane resin according to any one of 1 to 8, wherein the polysiloxane resin is in a state of being uniformly dispersed or soluble in water. <7> <1> ~ <5> A paint comprising the polysiloxane resin according to any one of the above items. <8> The following general formula (I): R 1 n -Si-(OR 2 ) 4-n (I) (In the formula, R 1 are each independently an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, and R 2are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3.) with a polymer (B) having hydrolyzable silyl groups at both ends. <9> The condensation step is a step of condensing the silane compound (A), the polymer (B), and a silane compound (C) having a radical polymerizable unsaturated group and a hydrolyzable silyl group. <8> The manufacturing method described in <10> a radical polymerization step of adding a monomer (D) having a radically polymerizable unsaturated group but not having a hydrolyzable silyl group after the condensation step, and performing radical polymerization; <8> or <9> The manufacturing method described in <11> <1> ~ <5> 10. A method for producing an aqueous solution containing a polysiloxane resin, the method comprising the step of dispersing, emulsifying, or dissolving the polysiloxane resin according to any one of the above items in water. [Example]

[0108] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0109] 〔material〕 The following materials were used in the examples and comparative examples.

[0110] <Silane compound (A)> Methyltrimethoxysilane (abbreviated as "M-TMS"): "Z-6033" manufactured by Dow Toray Industries, Inc. Phenyltrimethoxysilane (abbreviated as "Ph-TMS"): "Z-6124" manufactured by Dow Toray Industries, Inc. <Polymer (B)> (Meth)acrylic polymer having hydrolyzable silyl groups at both ends: (XMAPSA120S manufactured by Kaneka Corporation, glass transition temperature (Tg) -40°C) <Silane Compound (C)> Vinyltrimethoxysilane (abbreviated as "Vi-TMS"): "A-171" manufactured by Momentive <Monomer (D)> Methyl methacrylate (abbreviated as "MMA"): manufactured by Mitsubishi Gas Chemical Company, Inc. Butyl acrylate (abbreviated as "BA"): manufactured by Nippon Shokubai Co., Ltd. Ether sulfate type ammonium salt (abbreviated as "SR-10"): ADEKA Corporation "Adeka Rear Soap SR-10" manufactured by Acrylamide tertiary butyl sulfonate sodium: "ATB" manufactured by Toagosei Co., Ltd. S.” <Other ingredients> (Dehydration condensation catalyst) Lithium chloride (abbreviated as "LiCl"): Kanto Chemical Co., Ltd., neutral salt (Radical polymerization initiator) 2,2'-Azobis(2,4-dimethylvaleronitrile): Fujifilm Wako Pure Chemical Industries, Ltd. Company-made "V-65" (others) Condensed water (pure water) 2-Propanol: manufactured by Nacalai Tesque, Inc. [Measurement and evaluation methods] Measurements and evaluations in the examples and comparative examples were carried out by the following methods.

[0111] (synthesis) When polysiloxane-based resins were produced by the methods described in the Examples and Comparative Examples, if no gelation occurred during the synthesis (polymerization) of the polysiloxane-based resin, the resin was evaluated as "○ (good)", and if gelation occurred, the resin was evaluated as "× (bad)".

[0112] (Storage stability) An aqueous solution containing a polysiloxane resin with a solids concentration adjusted to 40% was sealed in a glass bottle and left to stand in a hot air dryer heated to 50°C. If the aqueous solution did not gel after 10 days of storage at 50°C, it was evaluated as "○ (good)", and if the aqueous solution gelled, it was evaluated as "× (bad)".

[0113] (Weather resistance (gloss retention)) The weather resistance of the cured product obtained by curing the obtained polysiloxane-based resin was evaluated with reference to WO 2016 / 052636 and Japanese Patent No. 5555449.

[0114] Briefly, an accelerated weathering test was conducted on the cured film (cured product) on the test piece prepared by the method described below using a metal halide lamp testing machine (Model KU-R5CI-A, manufactured by Daipla Wintes Co., Ltd.). The 60° gloss value of the cured film was measured before and after 400 hours of accelerated weathering test, and the gloss retention was calculated. The higher the gloss retention, the better the weathering resistance.

[0115] The test conditions for the accelerated weather resistance test are as follows:

[0116] Illuminance: 85mW / cm 2 Irradiation 63℃ 50% 6 hours Condensation 30℃ 98% 2 hours Shower 30 seconds before and after condensation.

[0117] (flexibility) The flexibility of the cured product obtained by curing the obtained polysiloxane-based resin was measured with reference to JIS A6909. Briefly, the polysiloxane-based resin was applied to a 0.3 mm thick galvanized steel plate to a film thickness of 50 μm, and then cured for two weeks at 23°C and 50% RH to form a coating film (cured product). After curing, the galvanized steel plate was bent 90 degrees with a curvature diameter of 10 mm to measure the flexibility of the coating film (cured product). If no cracks occurred in the coating film when bent, it was rated as "good," and if cracks occurred in the coating film, it was rated as "poor."

[0118] Example 1 (Preparation of Co-condensation Product) A reactor equipped with a stirrer, thermometer, and reflux condenser was charged with the silane compound (A), polymer (B), and silane compound (C) in the amounts and types shown in Table 1, along with LiCl as a dehydration condensation catalyst and pure water as condensation water, and the mixture was refluxed and stirred at 65°C for 3 hours to produce a co-condensation product (condensation step). No gelation occurred during the condensation reaction.

[0119] (Preparation of Graft Cocondensation Product) A reactor equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen gas inlet tube, and a dropping funnel was The co-condensation product obtained in the condensation step was charged, and the temperature was raised to 65°C while introducing nitrogen gas, and then a mixed solution of the amount and type of monomer (D) shown in Table 1 and 0.1 parts by weight of V-65 as a polymerization initiator was added dropwise from the dropping funnel at a constant rate over 5 hours. After that, the mixture was stirred at 65°C for 2 hours and then cooled to room temperature to obtain a polysiloxane resin as a graft co-condensation product (radical polymerization step).

[0120] (Preparation of aqueous solution containing polysiloxane resin) The prepared polysiloxane resin was subjected to devolatilization using a rotary evaporator until the nonvolatile content reached 90% or more. The resulting devolatilized polysiloxane resin was then dissolved in water to a nonvolatile content of 40% and cooled to room temperature to obtain an aqueous solution containing the polysiloxane resin.

[0121] (Preparing water-based paint) The resulting aqueous solution containing the polysiloxane resin was mixed with the components according to the formulation shown in Table 2 to prepare a water-based paint containing the polysiloxane resin (white base paint).

[0122] (Preparation of test specimens) Test pieces for measuring and evaluating "weather resistance" were prepared with reference to International Publication No. 2016 / 052636. Briefly, the water-based paint prepared above was applied to an aluminum plate (50 mm x 150 mm) coated with Hi-Pon Fine Primer II (manufactured by Nippon Paint Co., Ltd.) as a primer using an air spray to a dry film thickness of approximately 40 μm, and the resulting coating was dried at 23°C and 50% RH for one week to obtain a coated plate (aluminum plate coated with the cured product). This coated plate was used as the test piece.

[0123] [Examples 2 to 4, Comparative Examples 1 to 5] A polysiloxane resin, a solution containing the polysiloxane resin, and an aqueous paint were prepared in the same manner as in Example 1, except that the type and amount of each component was changed as shown in Tables 1 and 2. The resulting polysiloxane resin and the cured product obtained by curing the polysiloxane resin were measured and evaluated for the presence or absence of gelation during synthesis, storage stability, weather resistance, and flexibility. The results are shown in Table 1.

[0124] [Table 1]

[0125] In Table 1, the units of each value are parts by weight, except for the equivalent number of condensation water.

[0126] [Table 2]

[0127] In Table 2, the units of each value are parts by weight.

[0128] 〔result〕 Table 1 shows that the polysiloxane resins of Examples 1 to 4 can provide cured products with excellent flexibility and weather resistance. It also shows that the polysiloxane resins of Examples 1 to 4 did not undergo gelation during synthesis and had excellent storage stability. That is, according to one embodiment of the present invention, a polysiloxane resin can be provided that can provide a cured product with excellent flexibility and weather resistance, and the polysiloxane resin also has excellent storage stability.

[0129] On the other hand, a comparison of Examples 1 to 4 with Comparative Examples 1 and 2 reveals that when polymer (B) is not used (when polymer (B) is not used and a large amount of monomer (D) is grafted), the flexibility of the cured product obtained by curing the resulting resin is poor. Furthermore, a comparison of Examples 1 to 4 with Comparative Example 3 reveals that when polymer (B) is not used and the amounts of inorganic components, silane compound (A) and silane compound (C), used are drastically reduced, the weather resistance of the cured product obtained by curing the resulting resin is poor. A comparison of Examples 1 to 4 with Comparative Examples 4 and 5 clearly reveals that when polymer (B) is not used and the amount of monomer (D) used is reduced, the storage stability of the resulting resin is reduced and the flexibility of the cured product obtained by curing the resin is poor. Furthermore, Comparative Example 5 reveals that when such a resin is synthesized under conditions with a high water content, gelation occurs, making it virtually impossible to obtain the resin. From the above, it was shown that if polymer (B) is not used, the flexibility and weather resistance of the cured product obtained by curing the resulting resin cannot be achieved at the same time, or the resin itself cannot be synthesized. [Industrial Applicability]

[0130] The present invention provides a polysiloxane resin that can provide a cured product that is excellent in flexibility and weather resistance. The cured product that is excellent in flexibility and weather resistance can be suitably used in coating agents, water-based paints, etc.

Claims

1. The following general formula (I): R １ ｎ -Si-(OR ２ ) ４－ｎ ・・・(I) (In the formula, R １ are each independently an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, and R ２ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3; a polymer (B) having hydrolyzable silyl groups at both ends thereof, the condensation step is a step of condensing the silane compound (A), the polymer (B), and a silane compound (C) having a radical-polymerizable unsaturated group and a hydrolyzable silyl group, a radical polymerization step of adding, after the condensation step, a monomer (D) having a radically polymerizable unsaturated group but not having a hydrolyzable silyl group, and performing radical polymerization; The monomer (D) includes a monomer having a salt structure formed from an acid and a base. A method for producing polysiloxane resins.

2. The following general formula (I): R 1 n -Si-(OR 2 ) 4-n...(I) (wherein, each R 1 is independently an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, each R 2 is independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3), and a structural unit (b) derived from a polymer (B) having hydrolyzable silyl groups at both ends; Including, Furthermore, a structural unit (c) derived from a silane compound (C) having a radical polymerizable unsaturated group and a hydrolyzable silyl group; A structural unit (d) derived from a monomer (D) having a radical polymerizable unsaturated group and not having a hydrolyzable silyl group; Including, The monomer (D) includes a monomer having a salt structure formed from an acid and a base. A method for producing an aqueous solution containing a polysiloxane-based resin, comprising a step of dispersing, emulsifying, or dissolving a polysiloxane-based resin in water, The silane compound (A), and the polymer (B), the condensation step is a step of condensing the silane compound (A), the polymer (B), and the silane compound (C), a radical polymerization step of adding the monomer (D) having a radically polymerizable unsaturated group and carrying out radical polymerization after the condensation step, A method for producing an aqueous solution containing a polysiloxane resin, further comprising the step of producing the polysiloxane resin by the method for producing a polysiloxane resin.

3. A method for producing an aqueous solution containing a polysiloxane-based resin as described in claim 2, wherein the aqueous solution containing the polysiloxane-based resin is an aqueous paint.

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