JPH08283580A - Silicone having oxazolidine ring and urethane resin composition containing the silicone - Google Patents

Abstract

PURPOSE: To obtain a urethane resin composition having good weatherability and curability and useful for a sealing agent, an adhesive, a coating material, etc., by using a new silicone and a urethane prepolymer as the constituents. CONSTITUTION: The silicone having an oxazolidine ring in the molecule and represented by formula I (wherein R<1> and R<2> are each a 1-6C hydrocarbon group; R<3> is a 1-10C divalent hydrocarbon group; R<4> is a divalent residue obtained by removing isocyanato groups from a polyisocyanate compound; R<5> is a 2-3C linear or branched divalent aliphatic hydrocarbon group; R<6> to R<9> are each H or a 1-12C monovalent hydrocarbon group; R<10> and R<11> are each H or a 1-20C monovalent hydrocarbon group; X is NH, O or S; a is 0 to 2; and n is 10 to 10,000) is synthesized by reacting a polysiloxane of formula II with an isocyanate having an oxazolidine ring and represented by formula III. This silicone is reacted with a urethane prepolymer having terminal isocyanato groups to give a urethane resin composition having a molar ratio of the isocyanato groups to the oxazolidine ring of (1 to 2,000):1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel silicone and a urethane resin composition containing it. Specifically, it contains a silicone having two or more oxazolidine rings in one molecule, and a urethane prepolymer, and is useful as a sealing material, an adhesive, a coating material, etc., and has excellent weather resistance and curability. The present invention relates to a silicone and urethane resin composition that realizes a liquid moisture curable resin composition.

[0002]

2. Description of the Related Art Urethane resins having isocyanate groups at their molecular ends are widely used as base polymers for sealants (sealing materials), adhesives, waterproof materials, etc., but have urethane bonds in the main chain. However, there is a problem that weather resistance is poor, such as cracking or chalking after several months of outdoor exposure. In order to solve such a problem, ultraviolet absorbers and antioxidants are currently added to urethane resins, but they have not been sufficiently effective.

On the other hand, because of its excellent weather resistance, durability and heat resistance, silicone is used as an elastic sealing material in high-rise buildings.

[0004]

The use of silicone having such excellent properties as a modifier for improving the weather resistance of urethane resin has been investigated, but it has the following problems. That is, since silicone does not react with the urethane prepolymer, when the addition amount exceeds a certain amount, the added silicone bleeds from the urethane prepolymer. Therefore, the performance of the silicone as a modifier is not sufficiently exhibited.

An object of the present invention is to solve the above-mentioned problems of the prior art, and it reacts well with the urethane prepolymer and is incorporated into the urethane resin after curing, so that the performance as a modifier is sufficiently improved. (EN) It is an object to provide a silicone that can be exerted to realize a urethane resin having excellent weather resistance, and a urethane resin composition containing the silicone.

[0006]

In order to achieve the above-mentioned object, the inventors of the present invention have studied the silicone which, when added to the urethane prepolymer, is incorporated into the urethane resin after curing. A novel silicone having a plurality of oxazolidine rings and a plurality of urethane bonds having a structure represented by [1] was synthesized, and it was found that the silicone can suitably react with a urethane prepolymer to achieve the above object, The present invention has been completed.

That is, the silicone of the present invention provides a silicone having an oxazolidine ring in the molecule, represented by the following formula [1].

[Chemical 2](In the above formula [1], R¹~ R¹¹And X, Navi
And a and n are as follows. R¹, R²; Each independently, monovalent carbon having 1 to 6 carbon atoms
Indicates a hydrogenated group. Note that R¹And R²Are the same
They may be different from each other. R³1 to 1 carbon atoms
A divalent hydrocarbon group of 0 is shown. R^Four; Polyisocyanate
Divalent compounds obtained by removing isocyanate groups from
Indicates a residue. R^FiveA straight or branched chain having 2 to 3 carbon atoms
Is a divalent aliphatic hydrocarbon group having R⁶, R⁷,
R⁸, R ⁹; Each independently, hydrogen atom or carbon number 1
~ 12 monovalent hydrocarbon groups are shown. Note that R⁶, R⁷,
R⁸And R⁹Are the same but different from each other
May be. R^Ten, R¹¹; Each independently, hydrogen atom or
Represents a monovalent hydrocarbon group having 1 to 20 carbon atoms. Note that R
^TenAnd R¹¹Are the same or different
Good. X; an atom selected from NH, O and S, or
Indicates an atomic group. a; Shows an integer of 0 to 2. n; 10
Indicates an integer of 10,000. )

The urethane resin composition of the present invention contains the urethane prepolymer having an isocyanate group at the terminal and the silicone of the present invention, and the molar ratio of isocyanate group / oxazolidine ring is 1 to 2000. A urethane resin composition is provided.

The present invention will be described in detail below. The silicone of the present invention has two or more oxazolidine rings and a urethane bond in one molecule, and has the following formula [1]
It is shown by.

Embedded image

In the above formula [1], R ¹ and R
² is a monovalent hydrocarbon group having 1 to 6 carbon atoms. Such a hydrocarbon group is a linear or branched aliphatic hydrocarbon group or an aromatic hydrocarbon group which may have a substituent (side chain), specifically, an alkyl group. , Alkenyl group, alkynyl group, aryl group and the like. Specifically, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group,
Examples thereof include n-hexyl group, i-hexyl group, vinyl group, allyl group and phenyl group. Above all,
A methyl group, an ethyl group, a vinyl group, a phenyl group and the like are preferable from the viewpoint of easy availability of raw materials. Note that R ¹ and R
² may be the same or different from each other,
Further, R ^{1 s} or R ^{2 s} that bond to the same Si may be the same or different.

R ³ represents a divalent hydrocarbon group having 1 to 10 carbon atoms and has a linear or branched aliphatic hydrocarbon group or a substituent (side chain). Is an aromatic hydrocarbon group, and examples thereof include an alkylene group and an aralkylene group. Specific examples thereof include an ethylene group and a propylene group, and the propylene group is preferable from the viewpoint of availability of raw materials and the price thereof.

R ⁴ is a divalent residue obtained by removing an isocyanate group from an organic polyisocyanate compound. Examples of R ⁴ include all divalent groups derived from known polyisocyanate compounds. For example, a divalent residue obtained by removing an isocyanate group from a simple polyisocyanate compound containing only an aliphatic or aromatic hydrocarbon group such as hexamethylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and the like. Number 4 to 1
Examples thereof include an alkylene group having 2 to 5 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, an arylene group having 6 to 15 carbon atoms, and an aralkylene group having 7 to 15 carbon atoms. R ⁴ is a polyisocyanate compound and a molecular weight of 400 to 100 containing at least two hydrogen atoms capable of reacting with an isocyanate group.
It may be a residue obtained by removing the isocyanate group from the urethane prepolymer of the terminal isocyanate obtained by a known method such as described in the literature by reacting with the compound of 00. The urethane prepolymer will be described in detail later.

R ⁵ is a linear or branched divalent aliphatic hydrocarbon group having 2 to 3 carbon atoms and represents an alkylene group, an alkenylene group or an alkynylene group. Specific examples thereof include an ethylene group, a propylene group, and a propynyl group, and the ethylene group and the propylene group are preferable from the viewpoint of availability of raw materials and the price thereof.

R ⁶ , R ⁷ , R ⁸ and R ⁹ are hydrogen atoms or monovalent hydrocarbon groups having 1 to 12 carbon atoms. Such a hydrocarbon group is an aliphatic hydrocarbon group having a straight chain or a branched chain, or an aromatic hydrocarbon group which may have a substituent (side chain). They may be combined to form an alicyclic structure such as a 5-membered ring or a 6-membered ring. Specific examples include an alkyl group (especially having 1 to 6 carbon atoms), an aralkyl group, an alkynyl group, an alkynyl group and an aryl group. More specifically, hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-
Propynyl group, i-propynyl group, n-butyl group, i-
Butyl group, t-butyl group, n-butyryl group, i-butyryl group, n-pentyl group, n-hexyl group, n-hexynyl group, octyl group, nonyl group, decyl group, dodecyl group,
Examples thereof include a phenyl group, a phenyl group which may be substituted with two substituents, and a benzyl group. In particular, hydrogen atom,
A methyl group and an ethyl group are preferable in terms of curability and the like. In addition,
R ⁶ , R ⁷ , R ⁸ and R ⁹ may be the same or different from each other.

R ¹⁰ and R ¹¹ are hydrogen atoms or monovalent hydrocarbon groups having 1 to 20 carbon atoms. Such a hydrocarbon group is an aliphatic hydrocarbon group having a linear or branched chain, or an aromatic hydrocarbon group which may have a substituent (side chain), and is bonded to each other to form 5 You may comprise alicyclic, such as a membered ring and a 6-membered ring. Specifically, an alkyl group (especially having 1 to 6 carbon atoms), an aralkyl group, an alkynyl group,
Examples are a cycloalkyl group and an arylene group. More specifically, methyl group, ethyl group, n-propyl group, i-
Substituted with 2 substituents: propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, n-hexyl group, octyl group, nonyl group, decyl group, dodecyl group, phenyl group Examples of the phenyl group, benzyl group, and the like which may be contained are included. Since a group having a higher electron donating property cures faster, it is preferable to use these substituents properly depending on the case.

In the formula [1], n represents an integer of 1 to 10,000. This is because when n exceeds 10,000, the content of the oxazolidine ring with respect to the molecular weight (molecular size) is small and the curing becomes insufficient when used as a modifier for the urethane resin. Preferably, n is 10 to 5,000, more preferably 100 to 1,000. a represents the integer of 0-2.

In the silicone represented by the above formula [1], a part of R ¹ is represented by the following formula [2]

[Chemical 4] In this case, the silicone of the above formula [1] is a silicone having more than two oxazolidine rings in one molecule. In the above formula [2], R ^{2 to} R ⁷ and a are the same as those in the above formula [1].

The silicone of the present invention having two or more oxazolidine rings in one molecule represented by the formula [1] is a polysiloxane having active hydrogen at the terminal represented by the following formula [3]: It can be synthesized by reacting an oxazolidine ring-containing isocyanate represented by the following formula [4] at room temperature in the absence of a catalyst. In addition,
In the formula [3] and the formula [4], and further in the formula [5], the formula [6], the formula [7], the formula [8], the formula [9] and the formula [10] shown below, R ^{1 to} R ¹¹ and X, a and n are the same as those in the above formula [1].

[0019]

Embedded image

The polysiloxane having active hydrogen at the terminal represented by the above formula [3] is obtained by adding a terminal silanol polysiloxane represented by the following formula [5] and an alkoxysilane represented by the following formula [6] to dibutyltin. Dilaurate, dibutyltin diacetate, dibutyltin mercaptide,
Dibutyltin thiocarboxylate, dibutyltin dimaleate, dioctyltin mercaptide, dioctyltin thiocarboxylate, divalent tin compounds such as tin 2-ethylhexanoate, terralaisopropyl titanate, tetranormalptyl titanate, butyl titanate dimer, tetra Using a tetravalent titanium compound such as (2-ethylhexyl) titanate or tetramethyl titanate as a catalyst, the pressure is reduced to 60 to 120 ° C, preferably 70 to 90 ° C.
It can be synthesized by reacting for 2 to 10 hours.

[0021]

[Chemical 6]

The terminal silanol polysiloxane represented by the formula [5] has an average molecular weight of 90 to 750000, preferably 7500 to 75000 (that is, n = 100).
It is especially effective for modifying the urethane prepolymer. Moreover, as the alkoxysilane represented by the formula [6], γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
Amino group-containing silanes such as γ-aminopropylmethyldimethoxysilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldiethoxysilane,
mercapto group-containing silanes such as γ-mercaptopropylmethyldiethoxysilane; and the like.

Here, when dialkoxysilane or triacyloxysilane is used as the alkoxysilane represented by the formula [6], in the synthesis of the polysiloxane having active hydrogen represented by the formula [3], The polysiloxane of the formula [5] is further added to the remaining alkoxy groups of the alkoxysilane of the formula [6] bonded to the polysiloxane of the formula [5], and the polysiloxane of the formula [5] is substituted with the alkoxy of the formula [6]. It is also possible to bind silane. As a result, for example, a polysiloxane represented by the following formula [7], that is, a polysiloxane represented by the formula [3], has active hydrogen exceeding 2 (3 in the example of the formula [7]) at the terminal. It is also possible to synthesize polysiloxane.

[Chemical 7]

The silicone of the present invention is obtained by reacting the thus obtained polysiloxane having an active hydrogen of more than 2 at the terminal with an isocyanate having an oxazolidine ring represented by the above formula [4]. 1
A silicone having more than 2 oxazolidine rings in the molecule can be obtained.

As the polysiloxane represented by the formula [3] and having active hydrogen at the terminal, a commercially available product can be preferably used. As the terminal carbinol-modified silicone of X = O, X-22-160AS, KF-6001,
KF-6002, KF-6003 (above, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like; As the terminal amino-modified silicone of X = N, X-22-161AS, X-22-161A, X-.
22-161B, X-22-161C and the like (above, manufactured by Shin-Etsu Chemical Co., Ltd.); X-22-167B (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like as the terminal mercapto-modified silicone of X = S;
Are illustrated respectively.

On the other hand, the isocyanate having an oxazolidine ring represented by the formula [4] used in the synthesis of the silicone of the present invention represented by the formula [1] is an N-hydroxyalkyloxazolidine represented by the following formula [8]. Can be synthesized by reacting with a polyisocyanate compound represented by the formula [9].

[0027]

Embedded image

The N-hydroxyalkyloxazolidine represented by the above formula [8] is synthesized by a known method from the corresponding aldehyde or ketone and N-hydroxyalkylamine.

As the aldehyde, formaldehyde,
Acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, 2
-Aliphatic aldehydes such as methylbutyraldehyde, 3-methylbutyraldehyde, hexylaldehyde, 2-methylpentylaldehyde, octylaldehyde, 3,5,5-trimethylhexylaldehyde; benzaldehyde, methylbenzaldehyde, trimethylbenzaldehyde, ethylbenzaldehyde, isopropyl Aromatic aldehydes such as benzaldehyde, isobutylbenzaldehyde, methoxybenzaldehyde, dimethoxybenzaldehyde, trimethoxybenzaldehyde;
Etc. are illustrated. As the ketone, ketones such as acetone, methylethylketone, methylpropylketone, methylisopropylketone, diethylketone, methylbutylketone, methylisobutylketone, methyl-t-butylketone, diisobutylketone, cyclopentanone and cyclohexanone are preferable.

N-hydroxyalkylamines are mainly produced from alkylene oxides and excess ammonia. For example, ethanolamine is a reaction product of ethylene oxide and aqueous ammonia under high temperature and high pressure, and from the product monoethanolamine, diethanolamine,
It is obtained by separating triethanolamine and excess ammonia water by distillation. Examples of N-hydroxyalkylamine include aminoethylethanolamine, diethylethanolamine, dimethylethanolamine,
(2-hydroxyethyl) amine, (2-hydroxypropyl) amine, bis-N- (2-hydroxyethyl)
Mention may be made of amines, bis-N- (2-hydroxypropyl) amine and N-2- (hydroxyethyl) -N- (2-hydroxypropyl) amine. Among them, bis-N-2-hydroxyethylamine, bis-N-2-hydroxypropylamine and N-2-hydroxyethyl-N-2-hydroxypropylamine are particularly preferably used in terms of price and the like.

The N-hydroxyalkyloxazolidine represented by the formula [8] is synthesized by reacting the above-mentioned aldehyde or ketone and hydroxyalkylamine with a hydroxyalkylamine in a nitrogen molar amount corresponding to the number of moles of aldehyde or the like. However, in this synthesis, preferably, the aldehyde or ketone is in the range of 1.01 to 1.5 mol, and particularly preferably 1.0 mol per 1 mol of nitrogen.
It is used in excess in the range of 1 to 1.1 mol. The reason for this is that unreacted N-hydroxyamine is difficult to separate from the product and reacts with the isocyanate described below, so that the isocyanate having an oxazolidine ring represented by the formula [4] and the silicone storage stability of the present invention are stable. This may cause a decrease in

The above synthetic reaction of N-hydroxyalkyloxazolidine is carried out in a solvent such as toluene or xylene under reflux. The reaction time is preferably 6 to 24 hours, and particularly preferably 8 to 12 hours. If the reaction time is less than 6 hours, the reaction may not proceed completely, and if it exceeds 24 hours, the reaction mixture may be colored. The reaction is preferably carried out in a normal atmosphere.
After completion of the reaction, excess aldehyde or ketone is distilled off from the obtained product under reduced pressure to obtain N-hydroxyalkyloxazolidine represented by the above formula [8].

On the other hand, as the polyisocyanate compound represented by the formula [9], all known polyisocyanates used in the synthesis of urethane resins and the like can be used.
Specific examples include paraphenylene diisocyanate, tolylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, octadecyl diisocyanate, naphthalene diisocyanate, 4,4′-diphenylmethane diisocyanate, isophorone diisocyanate, and modified products thereof. To be done. In addition, such polyisocyanate compounds may be used alone or in combination of two or more kinds.

As the polyisocyanate compound represented by the formula [9], the polyisocyanate compound is reacted with a compound having a weight average molecular weight of 400 to 10,000 containing at least two hydrogen atoms capable of reacting with an isocyanate group. Accordingly, a terminal isocyanate urethane prepolymer obtained by a known method such as described in the literature is also preferably exemplified. As this urethane prepolymer, the urethane prepolymer used in the urethane resin composition of the present invention which will be described in detail later is preferably used.

As described above, the isocyanate having an oxazolidine ring represented by the formula [4] includes the N-hydroxyalkyloxazolidine represented by the formula [8] and the polyisocyanate compound represented by the formula [9]. It is obtained by reacting. This reaction may be carried out at a temperature of about 50 to 100 ° C. under normal pressure using a suitable solvent as needed. In this reaction, the amount ratio of the N-hydroxyalkyloxazolidine represented by the formula [8] to the polyisocyanate compound represented by the formula [9] is 1 mol of the polyisocyanate compound based on 1 mol of the hydroxyl group of the N-hydroxyalkyloxazolidine. It is preferably not more than mol, more preferably 0.6 to 0.9 mol. When the amount of the polyisocyanate compound is 1 mol or more, the polyisocyanate compound is likely to remain. On the other hand, when the amount is less than 0.6, the amount of the desired isocyanate having an oxazolidine ring may not be sufficient.

The silicone of the present invention having two or more oxazolidine rings in one molecule of the present invention is obtained by the polysiloxane having an active hydrogen at the terminal represented by the formula [3] and the formula [3]. [4] and an isocyanate having an oxazolidine ring can be synthesized by reacting at room temperature in the absence of a catalyst with a suitable solvent if necessary.

The urethane resin composition of the present invention contains such a silicone of the present invention and a urethane prepolymer having an isocyanate group at the terminal. The silicone of the present invention suitably reacts with the urethane prepolymer, is incorporated into the urethane resin after curing, and exhibits an excellent urethane modifying effect. Therefore, according to the urethane resin composition of the present invention, it is possible to realize a urethane resin suitably modified with silicone and having excellent weather resistance.

The urethane prepolymer used in the present invention is not particularly limited, and various known urethane prepolymers obtained by reacting a polyhydroxyl compound and a polyisocyanate compound can be used.

Specific examples of the polyhydroxyl compound include known polyether polyols, polyester polyols, polymer polyols and the like. Examples of the polyether polyol include 1 of alkylene oxides such as ethylene oxide and tetrahydrofuran.
Examples thereof include products obtained by addition polymerization of one kind or two or more kinds of compounds having two or more active hydrogens. Examples of the compound having two or more active hydrogens include polyhydric alcohols such as ethylene glycol, glycerin, hexanetriol, and trimethylolpropane; amines such as ethylenediamine and hexamethylenediamine; ethanolamine;
Examples are alkanolamines such as propanolamine; and polyhydric phenols such as resorcinol and bisphenol. As the polyester polyol, a condensate of a polyhydric alcohol exemplified by the polyether polyol and a polybasic carboxylic acid such as adipic acid, fumaric acid, maleic acid, phthalic acid or pyromellitic acid; castor oil, castor oil and Examples thereof include a condensation product of a hydroxycarboxylic acid such as a reaction product of ethylene glycol and the polyhydric alcohol; a lactone polymer obtained by ring-opening polymerization of caprolactone, valerolactone and the like with an appropriate polymerization initiator. Further, examples of the polymer polyol include those obtained by graft-polymerizing the above-mentioned polyether polyol or polyester polyol with an ethylenically unsaturated compound such as acrylonitrile and methyl (meth) acrylate.

These polyols may be used alone or in combination of two or more kinds. In either case, the weight average molecular weight is 100 to 10,000.
It is preferable to use one having a degree of about 500 to 5 in particular.
It is preferable to use those of about 000.

On the other hand, as the polyisocyanate compound, all known polyisocyanates used for the synthesis of urethane resins and the like can be used. Specifically, paraphenylene diisocyanate, tolylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, octadecyl diisocyanate, naphthalene diisocyanate, 4,
Examples include 4'-diphenylmethane diisocyanate, isophorone diisocyanate, and modified products thereof. In addition, such polyisocyanate compounds may be used alone or in combination of two or more kinds.

In the urethane resin composition of the present invention, the amount ratio of the urethane prepolymer and the silicone of the present invention is not particularly limited, but the molar ratio of isocyanate group / oxazolidine ring is preferably 1 to 2000. The urethane resin composition is adjusted so that If the molar ratio of isocyanate group / oxazolidine ring exceeds 2000, the effect of adding the silicone of the present invention cannot be sufficiently obtained. On the contrary, if this ratio is less than 1, silicone having an oxazoline ring is not reacted in the composition. Since it remains as it is, there is a case in which inconvenience such as deterioration of curability and residual tack after curing may occur.

In the urethane resin composition of the present invention, in addition to such essential components, various known pigments, thixotropy imparting agents, antistatic agents, adhesiveness imparting agents, flame retardants, etc. may be used depending on the intended use. You may mix | blend the additive of above with a normal range.
Examples of the pigment include organic pigments such as azo pigments and copper phthalocyanine pigments, and various inorganic pigments. Examples of the thixotropy imparting agent include Aerosil (manufactured by Nippon Aerosil Co., Ltd.) and Disparlon (manufactured by Kusumoto Kasei Co., Ltd.). Examples of the antistatic agent generally include ionic compounds such as quaternary ammonium salts and amines, and hydrophilic compounds such as polyglycol and ethylene oxide derivatives. Examples of the adhesion-imparting agent include terpene resin, phenol resin, terpene-phenol resin, rosin resin and xylene resin. Examples of the flame retardant include chloroalkyl phosphate, dimethyl methylphosphonate, bromine / phosphorus compound, ammonium polyphosphate, diethyl bishydroxyethyl aminoethyl phosphate, neopentyl bromide.
Examples thereof include polyether and brominated polyether.

In addition to these, known additives used in urethane resin compositions such as fillers, plasticizers, dyes, antioxidants, antioxidants, adhesion promoters, dispersants, solvents, etc. are blended. May be.

The method for producing the urethane resin composition of the present invention is not particularly limited, and various production methods similar to those of the known one-pack type moisture-curable urethane resin composition can be used. For example, the urethane prepolymer and the silicone of the present invention,
Further, a suitable method is to exemplify a method in which an appropriate amount of additives to be blended is filled in a stirring device such as a mixing mixer, sufficiently kneaded under reduced pressure, and uniformly dispersed to obtain a composition. .

Although the silicone having an oxazolidine ring and the urethane resin composition containing the same according to the present invention have been described in detail above, the present invention is not limited to the above-mentioned examples, and is within the scope of the present invention. Of course, various improvements and changes may be made.

[0047]

EXAMPLES The present invention will be described in more detail with reference to specific examples of the present invention. Of course, the present invention is not limited to these examples.

<Synthesis of Silicone Having Active Hydrogen at the Terminal (Formula [3])> (Synthesis Example 1) 300 g of silanol-terminated dimethylpolysiloxane having an average molecular weight of 35,000, 4.6 g of γ-aminopropyltrimethoxysilane, 2- 0.003 g of tin ethylhexanoate was added, and the reaction was carried out at 80 ° C. for 5 hours while removing by-produced methanol under reduced pressure to obtain 300 g of silicone having an amino group at the end.

(Synthesis Example 2) 5300 g of γ-aminopropyltrimethoxysilane and 0.03 g of tin 2-ethylhexanoate were added to 300 g of silanol-terminated dimethylpolysiloxane having an average molecular weight of 3000, and methanol produced as a by-product under reduced pressure. The reaction was carried out at 80 ° C. for 5 hours while removing the above to obtain 300 g of silicone having an amino group at the end.

It was confirmed by ¹ H-NMR that the reaction proceeded in the above Synthesis Examples 1 and 2 to synthesize the desired silicone represented by the following formula [10].

[Chemical 9]

That is, the chemical shift of the methoxy group of the raw material γ-aminopropyltrimethoxysilane is 3.5.
It is 2 ppm. On the other hand, the chemical shift of the methoxy group of the silicone represented by the formula [10] is 3.45 ppm.
It was confirmed that silicone was produced.

<Synthesis of Isocyanate Compound (Formula [4]) Having Oxazolidine Ring> (Synthesis Example 3) 20 g of N-hydroxyethyl-2-phenyloxazolidine and xylylene diisocyanate 1
3.1 g of the compound is reacted at 60 ° C. for 3 hours to give a pale yellow isocyanate compound 3 having an oxazolidine ring.
3.1 g was obtained. The reaction was confirmed by infrared spectroscopic analysis (IR) to confirm the formation of urethane bond, and ¹ H.
-By NMR, it was confirmed by confirming the disappearance of the methylene peak (4.4 ppm) next to the diisocyanate group possessed by the unreacted xylylene diisocyanate and the appearance of the methylene peak (3.9 ppm) next to the reacted isocyanate group. .

(Synthesis Example 4) N-hydroxyethyl-2-
20 g of phenyloxazolidine and 14.6 g of isophorone diisocyanate were reacted at 60 ° C. for 3 hours to obtain 34.6 g of a light yellow target oxazolidine ring-containing isocyanate compound. The reaction can be confirmed by IR
Confirmation of production of a urethane bond by, and ¹ H-NMR
Unreacted isophorone diisocyanate has a peak of one methylisocyanate group (3.0 ppm)
Of methyl isocyanate group after the reaction of the other isocyanate group (2.95 ppm)
It was done by confirming the appearance of.

(Synthesis Example 5) 1000 g of polypropylene glycol having an average molecular weight of 1000 (Excenol 1020; manufactured by Asahi Glass Co., Ltd.) and 450 g of isophorone diisocyanate.
And 80 with dibutyltin dilaurate in a catalytic amount.
The reaction was performed at 24 ° C. for 24 hours to obtain a terminal isocyanate polyol. To this terminal isocyanate polyol, 200 g of N-hydroxyethyl-2-phenyloxazolidine was added and reacted at 60 ° C. for 3 hours to give a pale yellow isocyanate compound 165 having an oxazolidine ring.
0 g was obtained. The reaction was confirmed by confirming the formation of a urethane bond by IR, and eliminating the peak (3.0 ppm) of one methylisocyanate group of unreacted isophorone diisocyanate by ¹ H-NMR, and the other isocyanate group. It was carried out by confirming the appearance of the peak (2.95 ppm) of the methylisocyanate group after the reaction.

<Synthesis of Silicon Having Oxazolidine Ring (Formula [1])> (Synthesis Example 6) 300 g of silicone having an amino group at the terminal synthesized in Synthesis Example 1 has the oxazolidine ring synthesized in Synthesis Example 3 16 g of isocyanate compound
The mixture was added dropwise with stirring at room temperature to obtain 316 g of an oxazolidine ring-containing silicone. The reaction was confirmed by confirming by IR that the isocyanate group had completely disappeared and a urethane bond had been formed.

(Synthesis Example 7) 1300 g of the isocyanate compound having an oxazolidine ring synthesized in Synthesis Example 4 was added dropwise to 300 g of the amino-terminated silicone synthesized in Synthesis Example 1 at room temperature with stirring. 314.6 g of a silicone having an oxazolidine ring was obtained. The reaction was confirmed by confirming by IR that the isocyanate group had completely disappeared and a urethane bond had been formed.

(Synthesis Example 8) 4300 g of the oxazolidine ring-containing isocyanate compound synthesized in Synthesis Example 5 was added dropwise to 300 g of amino terminal silicone synthesized in Synthesis Example 1 at room temperature with stirring. 349.4 g of a silicone having an oxazolidine ring was obtained. The reaction was confirmed by confirming by IR that the isocyanate group had completely disappeared and a urethane bond had been formed.

(Synthesis Example 9) 5300 g of the isocyanate compound having an oxazolidine ring synthesized in Synthesis Example 4 was added dropwise to 300 g of amino terminal silicone synthesized in Synthesis Example 2 at room temperature with stirring. 353.8 g of a silicone having an oxazolidine ring was obtained. The reaction was confirmed by confirming by IR that the isocyanate group had completely disappeared and a urethane bond had been formed.

(Synthesis Example 10) 300 g of a terminal carbinol-modified silicone (KF-6003; manufactured by Shin-Etsu Chemical Co., Ltd.) having an average molecular weight of 5600 represented by the following formula [11], and an isocyanate compound having an oxazolidine ring synthesized in Synthesis Example 4 48.1 g was reacted with catalytic amount of dibutyltin dilaurate at 80 ° C. for 24 hours to obtain 348.1 g of silicone having an oxazolidine ring. The reaction was confirmed by confirming by IR that the isocyanate group had completely disappeared and a urethane bond had been formed.

[0060]

[Chemical 10]

(Example) Polypropylene glycol having an average molecular weight of 3000 (EXCENOL 3020; manufactured by Asahi Glass Co., Ltd.), polypropylene triol having an average molecular weight of 5000 (EXCENOL 5030; manufactured by Asahi Glass Co., Ltd.) and 4,4-
The terminal isocyanate group content synthesized from diphenylmethane diisocyanate (manufactured by MD Kasei) is 1.7% by weight.
100 parts by weight of the urethane prepolymer, 110 parts by weight of calcium carbonate (manufactured by Maruo Calcium Co.), 40 parts by weight of dioctyl phthalate (DOP), 5 parts by weight of titanium oxide,
15 parts by weight of xylene and silicone having an oxazolidine ring synthesized in Synthesis Examples 7 to 10 were blended and uniformly dispersed in a mixing mixer, and various one-component moisture-curable urethane resin compositions shown in Table 1 below. Got

After hitting the obtained resin composition on marble,
The weather resistance was tested by exposing it to the outdoors for 6 months and examining the occurrence of cracks and chalking. O indicates that no crack or chalking occurred, and X indicates that cracking occurred.

[0063]

[Table 1]

As shown in Table 1, Examples 1 to 6 of the present invention containing the oxazolidine ring-containing silicone of the present invention
No cracking or choking was observed on the surface even after an outdoor exposure test for 6 months, and it is understood that the sample has excellent weather resistance as compared with Comparative Example 1 in which the silicone is not mixed and Comparative Example 2 in which the amount is small. Further, in Comparative Example 3 in which the amount of silicone blended was large, curing was poor. From the above results, the effect of the present invention is clear.

[0065]

As described in detail above, according to the present invention, it is possible to obtain a novel silicone having an oxazolidine ring which is very effective as a modifier for a urethane prepolymer. Further, the urethane resin composition of the present invention containing this silicone, since the cured product is excellent in weather resistance,
It is useful for various applications such as sealing materials, adhesives, and coating agents.

Claims (2)

[Claims] 1. A silicone having an oxazolidine ring in the molecule, which is represented by the following formula [1]. Embedded image (In the above formula [1], R ^{1 to} R ¹¹ and X, and a and n are as follows. R ¹ and R ² are each independently a monovalent hydrocarbon group having 1 to 6 carbon atoms. R ¹ and R ² may be the same or different from each other R ³ ; represents a divalent hydrocarbon group having 1 to 10 carbon atoms; R ⁴ represents an isocyanate group from a polyisocyanate compound. except a divalent residue obtained by R ^5;.. represents a divalent aliphatic hydrocarbon group having a straight chain or branched chain of carbon atoms ^{2~3 R 6, R 7, R} 8, R ⁹ independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms.
R ⁶ , R ⁷ , R ⁸ and R ⁹ may be the same or different from each other. R ¹⁰ and R ¹¹ ; each independently a hydrogen atom or a carbon number of 1
~ 20 monovalent hydrocarbon groups are shown. In addition, R ¹⁰ and R
¹¹ may be the same or different. X: An atom or atomic group selected from NH, O and S is shown. a; Shows an integer of 0 to 2. n: Shows an integer of 10 to 10,000. 2. A urethane resin composition containing a urethane prepolymer having an isocyanate group at the terminal and the silicone according to claim 1 and having a molar ratio of isocyanate group / oxazolidine ring of 1 to 2000.