JP2000302981A - Curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition improved in the mechanical strength of the cured product thereof without impairing the quick curability thereof at high temperatures by including a polymer having an alkenyl group at its end, specific compound and specific platinum complex catalyst. SOLUTION: This composition is obtained by including (A) a polymer having at its end an alkenyl group of the formula H2C=C(R1) or the formula HC(R1)= CH (R1 is a <=10C hydrocarbon group), (B) a compound having at least 2 hydrosilyl groups in the molecule and (C) a platinum complex catalyst containing no conjugated base of a strong acid as a ligand, at preferably 10-1 to 10-8 mol, more preferably 10-3 to 10-6 mol, per mol of the unsaturated group in the component A. The component C is preferably a platinum-vinylsiloxane complex, and especially preferably platinum-1,3-divinyl-1,1,3,3- tetramethyldisiloxane complex, platinum-1,3,5,7-tetravinyl-1,3,5,7- tetramethylcyclotetrasiloxane complex or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a curable composition having improved mechanical properties, which is cured by a hydrosilylation reaction.

[0002]

2. Description of the Related Art Conventionally, various curable compositions have been developed which cure to form a rubber-like substance. Among them, those in which a polymer having one or more alkenyl groups in one molecule is cross-linked by using a curing agent having two or more hydrosilyl groups in one molecule, have a relatively long pot life at around room temperature. And has characteristics such as rapid curing by heating. As the main chain skeleton of the polymer, those having a polysiloxane type, a polyether type, a hydrocarbon type or the like have been developed, and are used as sealants for electric / electronic materials, potting agents, dental impression materials and the like.

[0003]

In the cured product using the so-called hydrosilylation reaction, since the crosslinked portion is constituted by a flexible and low-polarity carbon-silicon bond, a highly polar urethane crosslink or an epoxy crosslink can be formed. There was a problem that mechanical strength, specifically, tensile strength at break, compressive strength, hardness, etc., were lower than those of the used cured product. Normally calcium carbonate, carbon black,
Although reinforcing fillers such as silica are blended, there is a limit to the improvement in terms of the polymer skeleton and the crosslinked structure.

[0004] It is an object of the present invention to improve the mechanical strength of a cured product without impairing the rapid curability at high temperatures, which is a feature of a curing system using a hydrosilylation reaction.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to improve the mechanical strength of a cured product using a hydrosilylation reaction. As a result, the use of a specific alkenyl group at the terminal of the polymer has led to the above-mentioned problems. I found that my goal was achieved. That is, the present invention provides (a) general formula 1 or 2: H ₂ C = C (R ¹ )-(1) HC (R ¹ ) = CH- (2) (wherein R ¹ is a carbon atom having 10 or less carbon atoms) A polymer having an alkenyl group at the terminal represented by (hydrogen group), (b) 2
The present invention relates to a compound having at least two hydrosilyl groups, and (c) a curable composition containing, as an essential component, a platinum complex catalyst containing no conjugate base of a strong acid as a ligand.

In a preferred embodiment, the present invention relates to the curable composition, wherein R ¹ is a methyl group.

[0007] In a further preferred embodiment, the present invention relates to the curable composition, wherein the platinum complex is a platinum-vinylsiloxane complex.

In a further preferred embodiment, the platinum complex is a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex or platinum-1,3,5,7
-The curable composition which is a tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane complex.

As a further preferred embodiment, (a)
The curable composition wherein the main chain of the polymer of the component is a polyether-based polymer.

In a further preferred embodiment, the molecular weight distribution of the polyether polymer measured by size exclusion chromatography is 1.6 or less, and the molecular weight is 3,000 to 3,000.
50,000.

As a further preferred embodiment, (a)
Ingredients were compared to hydroxyl terminated polyethers by William
The present invention relates to the curable composition, which is a polymer obtained by dividing the mson ether synthesis reaction into two or more times.

Another preferred embodiment relates to the curable composition wherein the main chain of the polymer of the component (a) is a hydrocarbon polymer.

Another preferred embodiment relates to the curable composition wherein the main chain of the polymer of the component (a) is a (meth) acrylic polymer.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The object of the present invention is to provide the following:
Or _{2: H 2 C = C (} R 1) - (1) HC (R 1) = CH- (2) ( wherein R ¹ is the following hydrocarbon group 10 carbon atoms) in the terminal alkenyl group represented by (B) 2 molecules in the molecule
This is achieved by a curable composition comprising, as an essential component, a compound having at least two hydrosilyl groups and (c) a platinum complex catalyst containing no conjugate base of a strong acid as a ligand.

The polymer represented by the general formula 1 or 2
R in the alkenyl group represented by ¹For example,
Straight chain alkyl groups such as methyl, ethyl, propyl, butyl
Chill, pentyl, hexyl, heptyl, octyl, noni
Decyl, branched alkyl groups such as isopropyl,
Sobutyl, isopentyl, isohexyl and aryl groups,
For example, a phenyl group and the like can be mentioned.
Or a mixture of a plurality of types. further
In terms of reactivity and raw material availability, methyl groups are particularly
preferable. In the present invention, R¹Is not hydrogen
is important. Utilizing the conventional hydrosilylation reaction
In curing systems, R¹Was hydrogen,
The mechanical strength of the compound was insufficient. In the present invention
Is R¹A hydrocarbon group having 10 or less carbon atoms
Thereby, the mechanical strength of the cured product is improved.

The alkenyl group of the general formula (1) or (2) is preferably present on average at least 0.1 with respect to the molecular chain terminal of the polymer, and preferably from 0.5 to 5 from the viewpoint of curability.
It is good that there exist. More preferably, there are 0.8 to 2 pieces. From the viewpoint that a cured product exhibiting good rubber elasticity behavior can be obtained, it is particularly preferred that 0.9 to 1 be present. The number of alkenyl groups contained in one molecule of the polymer may be one or more, but is preferably 1.5 to 4 on average in order to obtain sufficient curability. When the number of alkenyl groups contained in one molecule of the polymer is less than 1, the curability becomes insufficient, and it becomes difficult to exhibit good rubber elasticity behavior.

The main chain skeleton of the polymer of the component (a) is not particularly limited, and various types can be used. If specifically exemplified, polyoxyethylene, polyoxypropylene, polyoxytetramethylene, polyether-based polymers such as polyoxyethylene-polyoxypropylene copolymer, dibasic acid such as adipic acid and glycol Polyester polymers obtained by condensation polymerization, ring-opening polymerization of lactones such as ε-caprolactone, ethylene-propylene copolymers, polyisobutylene, copolymers of isobutylene and isoprene, polychloroprene, polyisoprene, isoprene Of butadiene, acrylonitrile, styrene, etc., polyolefin polymer obtained by hydrogenating a copolymer of polybutadiene, isoprene or butadiene with acrylonitrile, styrene, etc., ethyl acrylate, butyl acrylate, methacrylic acid Such as methyl (Meth) acrylic ester-based (co) polymers obtained by polymerizing nomers, copolymers of the (meth) acrylic monomers with vinyl acetate, acrylonitrile, styrene, etc., polysulfide-based polymers, and ε-caprolactam Nylon-6 by ring-opening polymerization, Nylon-6 by condensation polymerization of hexamethylenediamine and adipic acid
6, polyamide polymers such as nylon 610 by condensation polymerization of hexamethylenediamine and sebacic acid, such as polycarbonate polymers and diallyl phthalate polymers by condensation polymerization of bisphenol A and carbonyl chloride.

Of the various main chain skeletons described above, those having a flexible skeleton having rubber elasticity after curing are preferable because the effects of the present invention are more easily exhibited. As the skeleton, the above-mentioned polyether-based polymer, hydrocarbon-based polymer,
Examples include (meth) acrylic polymers, but are not limited thereto.

The component (a) whose main chain is a polyether polymer will be described in detail below. The main chain skeleton may be a polymer having a structure represented by -RO- as a repeating unit. In this case, R may be a divalent organic group having 1 to 20 carbon atoms. Further, a homopolymer in which all of the repeating units are the same, or a copolymer containing two or more types of repeating units may be used. Further, the main chain may have a branched structure.

A specific example of R is -CH_TwoCH_Two−, −
CH (CH_Three) CH_Two-, -CH (C _TwoH_Five) CH_Two−, −
C (CH_Three)_TwoCH_Two-, -CH_TwoCH_TwoCH_TwoCH_Two-Etc.
No. In particular, R is -CH (CH_Three) CH_Two− Is
preferable.

The main chain skeleton of the polyether polymer can be obtained by, for example, ring-opening polymerization of a monoepoxide in the presence of an initiator and a catalyst.

Specific examples of the initiator include ethylene glycol, propylene glycol, butanediol, hexamethylene glycol, methallyl alcohol, bisphenol A, hydrogenated bisphenol A, neopentyl glycol, polybutadiene diol, diethylene glycol, triethylene glycol, and polyethylene. Examples include glycol, polypropylene glycol, polypropylene triol, polypropylene tetraol, dipropylene glycol, glycerin, dihydric alcohols such as trimethylolmethane, trimethylolpropane, and pentaerythritol, polyhydric alcohols, and various oligomers having a hydroxyl group.

Specific examples of the monoepoxide include ethylene oxide, propylene oxide, α-butylene oxide, β-butylene oxide, hexene oxide, cyclohexene oxide, styrene oxide,
Examples include alkylene oxides such as α-methylstyrene oxide, alkyl glycidyl ethers such as methyl glycidyl ether, ethyl glycidyl ether, isopropyl glycidyl ether, and butyl glycidyl ether, allyl glycidyl ethers, and aryl glycidyl ethers.

Known catalysts include alkali catalysts such as KOH and NaOH, acidic catalysts such as trifluoroborane-etherate, and complex metal cyanide complex catalysts such as aluminoporphyrin metal complex and cobalt zinc zinc cyanide-glyme complex catalyst. Things are used. KOH and NaOH
For example, when a conventional alkali catalyst is used, it is difficult to obtain a polymer having a number average molecular weight of 3000 or more due to a chain transfer reaction. However, when a double metal cyanide complex catalyst is used, the chain transfer is small. A polymer having a high molecular weight and a narrow molecular weight distribution can be obtained. In addition, a basic compound such as KO is used for a polyether polymer having a small number average molecular weight.
H, NaOH, KOCH ₃ , NaOCH ₃
Further, a bifunctional or higher alkyl halide such as CH ₂
A high molecular weight polyether polymer can also be obtained by a chain extension reaction by reacting BrCl, CH ₂ Cl ₂ , CH ₂ Br _{2 and the} like.

The object of the present invention is to provide a cured product having a mechanical strength,
In particular, in order to improve the tensile strength at break and elongation, the molecular weight (number average molecular weight measured by size exclusion chromatography, hereinafter abbreviated as number average molecular weight) of the polyether polymer is preferably 3,000 to 50,000, more preferably 5,000 to 30,000. Number average molecular weight is 30
If it is less than 00, the modulus is high, but the elongation is small, and as a result, only a cured product having a small breaking strength can be obtained. If the number average molecular weight exceeds 50,000, the polymer becomes very high in viscosity, and handling becomes difficult.

From the viewpoint of handling, even if the number average molecular weight is the same, it is preferable that the molecular weight distribution (the ratio of the weight average molecular weight to the number average molecular weight measured by size exclusion chromatography) is narrow, because the viscosity becomes low. The preferred range of the molecular weight distribution is 1.6 or less. The above double metal cyanide complex catalyst is a preferable polymerization method from the viewpoint that a polyether polymer having a narrow molecular weight distribution can be obtained.

The terminal alkenyl group of the polyether polymer is preferably represented by the general formula 3 or 4: H ₂ C ＣC (R ¹ ) —R ² —O— (3) HC (R ¹ ) = CH—R ² —O— (4) (wherein R ¹ is the same as above, and R ² has 1 or more carbon atoms containing, as a constituent atom, at least one selected from the group consisting of hydrogen, oxygen, and nitrogen). To 20 divalent organic groups). R ² is a divalent organic group having 1 to 20 carbon atoms, for example; —CH ₂ —, —C ₂ H ₄ —, —C ₃ H
_{6 -, - C 4 H 8} -, - C 5 H 10 -, - C 6 H 1 2 -, - C 7 H
_{14, -C 8 H 16 -,} C 9 H 18, -C 10 H 20 -, - CH (C
_{H 3) -, - CH 2} -CH (CH 3) -, - CH 2 -CH
_{(CH 3) -CH 2 -,} - C 2 H 4 -CH (CH 3) -, -
_{C 5 H 4 -, - CH} 2 -C 6 H 4 -, - CH 2 -C 6 H 4 -CH
_{2 -, - C 2 H 4} -C 6 H 4 - group, and the like. -CH _2- , -CH ₂ CH _2- , -CH ₂ C because of easy synthesis
H (CH ₃₎ - are preferred. Further, -CH ₂ -is particularly preferred from the viewpoint of easy availability of raw materials.

As a method for producing a polyether polymer having an alkenyl group represented by the general formula 3 or 4 at the terminal, a conventionally known method may be used. For example, a hydroxyl-terminated polyether obtained by the above-mentioned various polymerization methods may be used. A method in which a compound having an alkenyl group of the general formula 1 or 2 is reacted with an ether polymer to bond the compound with an ether bond, an ester bond, a urethane bond, a carbonate bond, or the like. For example, when an alkenyl group is introduced by an ether bond, a Williamson ether synthesis reaction can be applied, and NaOH, KOH, CH ₃ ONa, CH ₃ OK,
After reacting with a base such as t-BuOK to generate -OM (M is Na, K, or the like) by metal oxylation, a general formula 5 or 6: H ₂ C ＨC (R ¹ ) -R ² -X ( 5) A method of reacting an alkenyl group-containing halide represented by HC (R ¹ ) = CH—R ² —X (6) (wherein R ¹ and R ² are the same as above, where X is chlorine, bromine or iodine). Can be used.

As R ¹ , all of those described above can be suitably used, and only one kind or a mixture of plural kinds may be used. In view of reactivity and availability of the compound, a methyl group is particularly preferable. As R ² , all of those described above can be used, and only one kind or a mixture of plural kinds may be used. -CH _2- , -CH ₂ CH _2- , -CH ₂ CH (C
H ₃ ) — is preferable, and —CH ₂ — is particularly preferable because of high reactivity and availability of raw materials.

The unsaturated compound represented by the general formula (5) or (6)
Specific examples of the sum group-containing compound include H_TwoC = C (CH_Three)
-CH_Two-Cl, H_TwoC = C (CH_Three) -CH_Two-Br, H
_TwoC = C (CH_Three) -CH_Two-I, H_TwoC = C (CH_TwoC
H_Three) -CH_Two-Cl, H_TwoC = C (CH_TwoCH_Three) -CH_Two
-Br, H_TwoC = C (CH_TwoCH_Three) -CH_Two-I, H_TwoC
= C (CH_TwoCH (CH_Three)_Two) -CH_Two-Cl, H_TwoC =
C (CH_TwoCH (CH_Three)_Two) -CH_Two-Br, H_TwoC = C
(CH_TwoCH (CH_Three)_Two) -CH_Two-I, HC (CH _Three)
= CH-CH_Two-Cl, HC (CH_Three) = CH-CH_Two−
Br, HC (CH_Three) = CH-CH_Two-I and the like;
Particularly, from the viewpoint of reactivity, H_TwoC = C (CH_Three) -CH_Two−
Cl, H_TwoC = C (CH_Three) -CH_Two-Br, HC (C
H_Three) = CH-CH_Two-Cl, HC (CH_Three) = CH-C
H_Two-Br is preferred. In addition, raw material acquisition and synthesis
H for ease_TwoC = C (CH_Three) -CH_Two-Cl is particularly preferred.
Good.

When an alkenyl group of the formula (1) or (2) is introduced in this method, when the base is allowed to act on the hydroxyl-terminated polyether, the terminals are associated with each other as the metal oxylation proceeds, and the reaction system increases. Due to stickiness, metal oxylation may not be completed, and as a result, the introduction rate of alkenyl groups may decrease. This tendency becomes more remarkable as the molecular weight of the polyether increases, which is a negative factor in the improvement of the mechanical strength of the cured product, which is the object of the present invention.

In such a case, the above-mentioned William
It is preferable that the son ether synthesis reaction be divided into two or more steps, since the alkenyl group of the formula 1 or 2 can be introduced almost quantitatively to the terminal. The number of divisions may be any number as long as it is at least two times, but is preferably two times from the viewpoint of manufacturing efficiency. An alkenyl group can be quantitatively introduced simply by performing the reaction twice. For example, if the base is added in an amount less than 1 equivalent to the hydroxyl group in the first reaction, a sharp increase in viscosity in the final stage of metal oxylation is avoided, and a sufficient amount is added to the metal oxylated terminal. If the halides of the formulas 5 and 6 are added, an alkenyl group is introduced into the terminal, so that the viscosity of the reaction system once becomes equal to that before the addition of the base. After that, even if an excessive amount of the base is allowed to act on the remaining hydroxyl groups, the viscosity of the reaction system rises only slightly, and the alkenyl groups can be introduced almost quantitatively by further adding a halide. Becomes possible.

The alkenyl group introduction rate depends on the polymer.
^{In 1} H NMR, it can be calculated from the integral ratio between the olefin proton and the proton in the main chain.

As a method for introducing an alkenyl group, an isocyanate compound having an alkenyl group represented by Formula 1 or 2, a carboxylic acid, or an epoxy compound can be used.

As another preferred polymer of the component (a),
The hydrocarbon polymer will be described in detail. Examples of the hydrocarbon polymer that exhibits rubber elasticity upon curing include polyisobutylene, a copolymer of isobutylene and isoprene, a copolymer of polyisoprene, a copolymer of isoprene and butadiene, polybutadiene, hydrogenated polybutadiene, and hydrogenated polyisoprene. No.

Polyisobutylene having an alkenyl group of the formula (1) or (2) at its end can be prepared by using an initiator such as p-dicumyl chloride or 1,3,5-trichumyl chloride, and a Lewis acid catalyst such as TiCl ₄ . It is obtained by cationically polymerizing an isobutylene monomer in the presence and then converting the cation end by various methods. As a method for converting the cation terminal, for example, general formula 7 or 8: H ₂ C ＝ C (R ¹ ) —CH ₂ Si (R ³ ) ₃ (7) HC (R ¹ ) ＝ CH—CH ₂ Si (R ³ ) ₃ (8) (wherein, R ¹ is the same as above, and R ³ is a hydrocarbon group having 10 or less carbon atoms) (hereinafter described in JP-A-2-248406). formula 9 or _{10; H 2 C = C- (} CH 2) n -C (R 1) = CH 2 (9) H 2 C = C- (CH 2) n -CH = CH (R 1) (10 (Wherein R ¹ is the same as above, and n is an integer of 0 to 20).
606) and a method of dehydrohalogenating by reacting with aluminum silicate or a basic compound (described in JP-A-1-261405).

The method for synthesizing polyisoprene having an alkenyl group of the formula 1 or 2 at the end, a copolymer of isoprene and butadiene, polybutadiene, hydrogenated polybutadiene, and hydrogenated polyisoprene includes the following methods. The method used in the production of the above polyether-based polymer, that is, a method of reacting an unsaturated group-containing halide represented by the general formula 5 or 6 after metal oxylation by reacting various bases on hydroxyl group terminals. Can be. Also in this case, it is preferable to carry out the Williamson ether synthesis reaction by dividing it into two or more times, since the alkenyl group can be quantitatively introduced.

In addition, a method of reacting an isocyanate compound having an unsaturated group represented by Formulas 1 and 2, a carboxylic acid, or an epoxy compound can be applied.

Another polymer which is preferable as the component (a) of the present invention is a (meth) acrylic polymer. The (meth) acrylic polymer having an alkenyl group of the general formula 1 or 2 at the molecular terminal can be synthesized by various known methods. For example, a method using an alkenyl group-containing disulfide as a chain transfer agent described in JP-A-5-255415, or JP-A-5-2628.
No. 08-108, a method of synthesizing a (meth) acrylic polymer having a hydroxyl group at both terminals using a disulfide having a hydroxyl group, and further introducing an alkenyl group by utilizing the reactivity of the hydroxyl group. Is available.

A more efficient method for obtaining a (meth) acrylic polymer having an alkenyl group of the general formula 1 or 2 at the molecular terminal is described in JP-A-9-272714. Using a halide or a sulfonyl halide compound as an initiator, groups 8 and 9 of the periodic table,
General formula 11: —CH ₂ —C (R ⁴ ) (CO ₂ R ⁵ ) (X) (11) obtained by a polymerization method using a metal complex having a Group 11 or Group 11 element as a central metal as a catalyst. In the formula, R ⁴ is a hydrogen or methyl group, and R ⁵ has 1 to 1 carbon atoms.
An alkyl group of 20; an aryl group of 6 to 20 carbon atoms; an aralkyl group of 7 to 20 carbon atoms; X is chlorine, bromine, or iodine), and halogen of a (meth) acrylic polymer having a terminal structure represented by the formula: It is a method of converting into one or two alkenyl group-containing substituents.

This method is based on atom transfer radical polymerization (Atom Transfer®), which has been studied energetically recently.
(meth) acrylic polymer having a high ratio of the halogen represented by the formula 11 at the terminal is obtained by the living property of the main polymerization, and the halogen is quantitatively converted. It is possible to obtain a (meth) acrylic polymer having unsaturated groups of formulas 1 and 2 at the terminal at a high ratio.

In the present method, for example, o-, m-,
p-XCH_Two-C₆H_Four-CH_TwoX, R ^FiveO_TwoCC (H)
(X)-(CH_Two)_n-C (H) (X) -CO_TwoR^Five(However
Then R^Five, X is the same as above, and n is an integer of 0 to 20)
ester compounds with a halogen at the α-position or
Using a compound having a halogen as an initiator,
Monovalent copper compounds such as copper and cuprous bromide and 2,2'-bipyridi
In the presence of a catalyst such as a copper complex obtained from
By polymerizing the rill-based monomer, the end of the above formula 11 is obtained.
After obtaining a (meth) acrylic polymer having an end,
By converting the halogen by an appropriate method,
Polymer can be obtained.

As a method for converting the terminal halogen, after the above polymerization, a polymerizable alkenyl group and a compound represented by the general formula 1 or 2
A method of reacting a compound having an alkenyl group represented by the following formula as a second monomer; a method of reacting an organotin compound having an alkenyl group represented by the general formulas 1 and 2;
A method of reacting a terminal halogen of 1 with an elemental metal or an organometallic compound to metallize, and thereafter reacting an electrophilic compound having an alkenyl group of formulas 1 and 2;
A method of reacting a carboxylic acid, phenol, or amine compound having an alkenyl group represented by general formulas 1 and 2 is exemplified.

The compound (b) of the present invention, which has two or more hydrosilyl groups in the molecule, functions as a curing agent for the component (a). The compound of the component (b) is not particularly limited, and various compounds can be used. In other words, the general formula 12 or _{^{13: R 6 3 SiO- [Si}} (R 6) 2 O] a - [Si (H) (R 7) O] b - [Si (R 7) (R 8) O] c ^{_{-SiR 6 3 (12) HR 6}} 2 SiO- [Si (R 6) 2 O] a - [Si (H) (R 7) O] b - [Si (R 7) (R 8) O] c - SiR ⁶ ₂ H (13) (wherein, R ⁶ and R ⁷ are an alkyl group having 1 to 6 carbon atoms or a phenyl group, and R ⁸ is an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 10 carbon atoms) , A is 0 ≦ a ≦ 100,
b is an integer of 2 ≦ b ≦ 100, and c is an integer of 0 ≦ c ≦ 100), and a linear polysiloxane represented by the general formula 14:

[0045]

Embedded image (Wherein, R ⁹ and R ¹⁰ are an alkyl group having 1 to 6 carbon atoms or a phenyl group, R ¹¹ is an alkyl group having 1 to 10 carbon atoms,
An aralkyl group having 7 to 10 carbon atoms, d is 0 ≦ d ≦ 8, e is 2 ≦ e ≦ 10, f is an integer of 0 ≦ f ≦ 8, and 3
≦ d + e + f ≦ 10) can be used. These may be used alone or in combination of two or more. Among these siloxanes, from the viewpoint of compatibility with the organic polymer of the component (a), general formulas 15 and 16 having a phenyl group: (CH ₃ ) ₃ SiO— [Si (H) (CH ₃ ) O] _{g - [Si (C 6 H 5} ) 2 O] h -Si (CH 3) 3 (15) (CH 3) 3 SiO- [Si (H) (CH 3) O] g - [Si (CH 3) [ CH ₂ CH) (R ¹² ) C ₆ H ₅ ] O] _h —Si (CH ₃ ) ₃ (16) (wherein R ¹² is a hydrogen or methyl group, and g is 2 ≦ g ≦ 10
0 and h are integers of 0 ≦ h ≦ 100, and C ₆ H ₅ represents a phenyl group), or a linear siloxane represented by the following general formula 17 or 18:

[0046]

Embedded image (Wherein R ¹² is the same as above, i is 2 ≦ i ≦ 10, j is 0
≦ j ≦ 8, and an integer satisfying 3 ≦ i + j ≦ 10, and C ₆ H ₅ represents a phenyl group).

As the compound having two or more hydrosilyl groups in the molecule of the component (b), the compound having two or more alkenyl groups in the molecule may be further represented by the following formulas 12 to 18:
The compound obtained by subjecting the hydrosilyl group-containing compound shown in (1) to an addition reaction so that a part of the hydrosilyl group remains even after the reaction can be used. Various compounds can be used as the compound having two or more alkenyl groups in the molecule. For example, 1,4-pentadiene, 1,5-hexadiene, 1,6-heptadiene,
1,7-octadiene, 1,8-nonadiene, 1,9-
Hydrocarbon compounds such as decadiene, ether compounds such as O, O'-diallylbisphenol A and 3,3'-diallylbisphenol A, diallyl phthalate, diallyl isophthalate, triallyl trimellitate, tetraallyl pyromellitate, etc. And carbonate compounds such as diethylene glycol diallyl carbonate.

In the presence of a hydrosilylation catalyst, an excess amount of the compound containing a hydrosilyl group represented by the formulas 12 to 18 is added.
The compound can be obtained by slowly dropping the alkenyl group-containing compound. Among these compounds, the following compounds are preferred in consideration of the availability of raw materials, the ease of removal of excessively used siloxane, and the compatibility with the polymer of the component (a).

[0049]

Embedded image In addition, as a specific example of the component (b), JP-A-3-95
No. 266, JP-A-3-200807 and the like can be used. The polymer of the component (a) and the hydrosilyl group-containing compound of the component (b) can be mixed in any ratio, but from the viewpoint of curability, the molar ratio of the alkenyl group to the hydrosilyl group is 5 to 0.2. Is preferable, and it is especially preferable that it is 2.5-0.4. When the molar ratio exceeds 5, only a cured product of insufficient strength with insufficient curing is obtained, and when it is less than 0.2, a large amount of active hydrosilyl groups remains in the cured product even after curing. As a result, cracks and voids are generated, and a uniform and strong cured product cannot be obtained.

The curing reaction between the polymer of the component (a) and the compound containing a hydrosilyl group of the component (b) proceeds by mixing and heating the two components. A catalyst is added. As the hydrosilylation catalyst of the component (c) used in the present invention, a platinum complex catalyst containing no conjugate base of a strong acid as a ligand is particularly preferably used.

In the present invention, in order to improve the mechanical strength of the cured product, a polymer having a terminal having an unsaturated group represented by the general formula 1 or 2 is used. These are all disubstituted alkenyl groups, compared with monosubstituted alkenyl groups (wherein R ¹ is hydrogen in general formulas 1 and 2) which has been generally used in curing systems using a hydrosilylation reaction. Thus, steric hindrance is large and the curing reaction is slowed. Therefore, in order to maintain the rapid curing property at a high temperature, which is a feature of the curing system utilizing the hydrosilylation reaction, a more active catalyst is required. A catalyst satisfying such requirements is a platinum complex catalyst containing no conjugate base of a strong acid as a ligand.

Preferred as ligands in such a platinum complex are compounds having a carbon-carbon unsaturated bond, such as olefins, alkynes and vinylsiloxanes, and β-diketones and β-ketoesters. Specific examples of the olefin ligand of the platinum-olefin complex include 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene,
1,11-dodecadiene, 1,5-cyclooctadiene and the like. Specific examples of the ligand of the platinum-vinylsiloxane complex include 1,3-divinyl-1,1,3,3
-Tetramethyldisiloxane, 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane and the like.

Other examples of platinum complex catalysts that do not contain a conjugate base of a strong acid as a ligand include platinum-phosphine complexes (eg, Pt (PPh ₃ ) ₄ , Pt (PBu ₃ ) ₄ ), platinum-phosphine
Phosphite complexes (eg, Pt [P (OPh) ₃ ] ₄ , P
t [P (OBu) ₃ ] ₄ ), Ashby US Pat.
Nos. 9601 and 3159662 and a platinum-hydrocarbon complex, and Lamoreaux
And a platinum chloride-olefin complex described in U.S. Pat. No. 3,516,946.

Among these platinum complexes, a platinum-vinylsiloxane complex is preferable from the viewpoint of high reactivity, stability of the complex, and availability, and particularly, platinum-1,3-divinyl-1,1,1 3,3-tetramethyldisiloxane complex or platinum-1,3,5,7-tetravinyl-1,
A 3,5,7-tetramethylcyclotetrasiloxane complex catalyst is preferred.

These platinum complex catalysts may be used alone or in combination of two or more.

There are no particular restrictions on the amount of catalyst used,
(A) 10 ^-1 to 10 based on 1 mol of unsaturated group in the component
^It is good to use in the range of ^-8 mol. Preferably, 10 ^-3
It is preferable to use in the range of 10 to 10 ^-6 . Usage is 10 ^-8 mo
When the amount is less than 1, the curing reaction becomes extremely slow, which is not practically preferable. When the amount is more than 10 ^-1 mol, it is economically disadvantageous.

Many hydrosilylation catalysts are known in addition to the platinum complex catalyst containing no conjugate base of a strong acid as a ligand. For example, a radical initiator such as an organic peroxide or an azo compound, and a transition metal catalyst other than those described above.

As an example of a radical initiator, di-t
-Butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne, dicumyl peroxide, t -Butylcumyl peroxide, dialkyl peroxides such as α, α'-bis (t-butylperoxy) isopropylbenzene, benzoyl peroxide, p-chlorobenzoyl peroxide, m-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl Diacyl peroxides such as peroxides, peresters such as t-butyl perbenzoate, diisopropyl percarbonate, peroxydicarbonates such as 2-ethylhexyl percarbonate, 1,1-di (t-butylperoxy) ) Cyclohexane, 1,1-di t- butylperoxy) -3,
And peroxyketals such as 3,5-trimethylcyclohexane.

As the transition metal catalyst, for example, a salt
Platinized acid (H_TwoPtCl₆・ 6H_TwoO), Pt metal, P
Use t-metal for alumina, silica, carbon black, etc.
Supported on a body, dicarbonyldichloroplatinum, Rh
Cl (PPh_Three)_Three, RhCl _Three, Rh / Al_TwoO_Three, Ru
Cl_Three, IrCl_Three, FeCl_Three, PdCl_Two・ 2H_TwoO,
NiCl_Two, AlCl_ThreeAnd TiCl_FourAnd the like. I
However, when these catalysts are used, the curing speed becomes slow, which is favorable.
Not good.

If the components (a), (b) and (c) of the present invention are mixed and heated, a uniform cured product having excellent deep curability can be obtained without causing a phenomenon such as foaming. The curing conditions are not particularly limited, but it is generally preferable to cure at 0 to 200 ° C., preferably 30 to 150 ° C., for 5 seconds to 4 hours. In particular, at a high temperature of 80 to 150 ° C., a material which cures in a short time of about 5 seconds to 1 hour can be obtained.

The curable composition of the present invention comprises (a)
In addition to the three essential components (b) and (c), depending on the purpose of use, solvents, adhesion improvers, pot life extenders, plasticizers, anti-sagging agents, fillers, antioxidants, and ultraviolet absorption Agent,
Light stabilizers, lubricants, pigments, foaming agents, extenders and the like can be added as appropriate.

Specific examples of uses of the cured product obtained from the curable composition include sealing materials, adhesives, pressure-sensitive adhesives, elastic adhesives, paints, waterproof coatings, foams, and electronic and electric parts. Sealing agents, potting agents, films, gaskets, various molding materials, dental impression materials, and the like.

[0063]

EXAMPLES Specific examples of the present invention will be described below, but the present invention is not limited to the following examples. (Production Example 1) Polypropylene glycol having a number average molecular weight of 3000 and CH ₃ ONa (methanol solution) at 60 ° C.
And added methylene chloride to increase the molecular weight.
Next, 3-chloro-2-methyl-1-propene was added and reacted at 110 ° C. to obtain polypropylene glycol having a methallyl group at a terminal (polymer A). (Comparative Production Example 1) In Production Example 1, 3-chloro-2-
Except that 3-chloro-1-propene was used in place of methyl-1-propene, polypropylene glycol having an allyl group at the end was obtained in the same manner. (Polymer B) (Production Example 2) Using polypropylene glycol having a number average molecular weight of 2,000 as an initiator, propylene oxide was polymerized in the presence of a zinc hexacyanocobaltate glyme complex catalyst to obtain a polypropylene glycol having a number average molecular weight of 10,000. Was. Subsequently, 1.2 times equivalent of CH ₃ ONa (methanol solution) was added to the terminal hydroxyl group of this oligomer, and the terminal was metal-oxylated while removing methanol under reduced pressure. To this, 1.3 equivalents of 3-chloro-2-methyl-1-propene was added to obtain polypropylene glycol having a methallyl group at a terminal (polymer C). (Production Example 3) Using polypropylene glycol having a number average molecular weight of 2,000 as an initiator, propylene oxide was polymerized in the presence of a zinc hexacyanocobaltate glyme complex catalyst to obtain polypropylene glycol having a number average molecular weight of 10,000. Subsequently, 0.8 times equivalent of CH ₃ ONa (methanol solution) was added to the terminal hydroxyl group of this oligomer, and the terminal was metal-oxylated while removing methanol under reduced pressure. Here, 0.9-fold equivalent of 3-chloro-2-methyl-1-propene was added and reacted.
Further, 0.5 times equivalent of CH ₃ ONa (methanol solution) was added, and while removing methanol under reduced pressure, the remaining hydroxyl group terminals were subjected to metal oxylation, followed by 0.8 times equivalent of 3-chloro-2. By adding and reacting -methyl-1-propene, polypropylene glycol having a methallyl group at a terminal was obtained (Polymer D). (Comparative Production Example 2) In Production Example 3, 3-chloro-2-
Except that 3-chloro-1-propene was used instead of methyl-1-propene, polypropylene glycol having an allyl group at the end was obtained (Polymer E). (Production Example 4) Using polypropylene glycol having a number average molecular weight of 2,000 as an initiator, propylene oxide was polymerized in the presence of a zinc hexacyanocobaltate glyme complex catalyst to obtain polypropylene glycol having a number average molecular weight of 20,000. Subsequently, 0.8 times equivalent of CH ₃ ONa (methanol solution) was added to the terminal hydroxyl group of this oligomer, and the terminal was metal-oxylated while removing methanol under reduced pressure. Here, 0.9-fold equivalent of 3-chloro-2-methyl-1-propene was added and reacted.
Further, 0.5 times equivalent of CH ₃ ONa (methanol solution) was added, and while removing methanol under reduced pressure, the remaining hydroxyl group terminals were subjected to metal oxylation, followed by 0.8 times equivalent of 3-chloro-2. By adding and reacting -methyl-1-propene, a polypropylene glycol having a methallyl group at a terminal was obtained (Polymer F). (Production Example 5) Using polypropylene glycol having a number average molecular weight of 2,000 as an initiator, propylene oxide was polymerized in the presence of a zinc hexacyanocobaltate glyme complex catalyst to obtain a polypropylene glycol having a number average molecular weight of 25,000. Subsequently, 0.8 times equivalent of CH ₃ ONa (methanol solution) was added to the terminal hydroxyl groups of this oligomer, and the terminal was metal-oxylated while removing methanol under reduced pressure. Here, 0.9-fold equivalent of 3-chloro-2-methyl-1-propene was added and reacted.
Further, 0.5 times equivalent of CH ₃ ONa (methanol solution) was added, and while removing methanol under reduced pressure, the remaining hydroxyl group terminals were subjected to metal oxylation, followed by 0.8 times equivalent of 3-chloro-2. By adding and reacting -methyl-1-propene, polypropylene glycol having a methallyl group at a terminal was obtained (polymer G). (Production Example 6) Using polypropylene triol having a number average molecular weight of 3000 as an initiator, propylene oxide was polymerized in the presence of a zinc hexacyanocobaltate glyme complex catalyst to obtain polypropylene triol having a number average molecular weight of 19000. Subsequently, 0.8 times equivalent of CH ₃ ONa (methanol solution) was added to the terminal hydroxyl groups of this oligomer, and the terminal was metal-oxylated while removing methanol under reduced pressure. Here, 0.9-fold equivalent of 3-chloro-2-methyl-1-propene was added and reacted.
Further, 0.5 times equivalent of CH ₃ ONa (methanol solution) was added, and while removing methanol under reduced pressure, the remaining hydroxyl group terminals were subjected to metal oxylation, followed by 0.8 times equivalent of 3-chloro-2. By adding and reacting -methyl-1-propene, a polypropylene triol having a methallyl group at a terminal was obtained (Polymer H). (Comparative Production Example 3) In Production Example 6, 3-chloro-2-
A polypropylene triol having an allyl group at the end was obtained in exactly the same manner except that 3-chloro-1-propene was used instead of methyl-1-propene (Polymer I).

The polymers A to I produced as described above
Was analyzed by size exclusion chromatography for molecular weight (Mn) and molecular weight distribution (Mw / Mn). Size exclusion chromatography was performed at a column temperature of 40 ° C. using tetrahydrofuran as a mobile phase in a column packed with polystyrene gel (manufactured by Tosoh Corporation).
The introduction rate of the alkenyl group was determined by JNM-LA400 manufactured by JEOL Ltd.
(400 MHz) by ¹ H NMR analysis. The viscosity was measured by a B-type viscometer (BM type, rotor No. 4). Table 1 shows the results.

[0065]

[Table 1] (Examples 1 to 6 and Comparative Examples 1 to 3) Irganox-1010 manufactured by Ciba Specialty Chemicals as an antioxidant was added to each of the polymers obtained in Production Examples 1 to 6 and Comparative Production Examples 1 to 3. Parts were added and dissolved. Furthermore, platinum-1,3-divinyl-1,1,3,3
A xylene solution (3% by weight as platinum) of a tetramethyldisiloxane complex (hereinafter abbreviated as PtVTS) or an isopropanol solution of chloroplatinic acid (3% by weight as platinum atom) in a molar ratio of platinum atom / alkenyl group At 5
It was added so as to be × 10 ^-4 equivalents, and stirred sufficiently. Here, the polyhydrogensiloxane compound shown in Table 4 was converted to a hydrosilyl group / alkenyl group in a molar ratio of 1.1.
Was added so that

[0066]

Embedded image A small amount of the obtained curable composition is scooped with a toothpick,
The solution was dropped on a hot plate heated to 20 ° C., and the time until the gel was formed (curing time) was measured while slowly stirring. Table 1 shows the results.

Next, each composition to which PtVTS was added as a platinum catalyst was poured into a mold having a thickness of 3 mm, and defoamed under reduced pressure.
By heating at 30 ° C. for 30 minutes, a uniform cured product without foaming was obtained. From these cured products, JISK-
No. 3 dumbbell according to 6301 was punched out, and a tensile test was performed at a tensile speed of 200 mm / min and 23 ° C.
30% elongation modulus at (M _30), 50% elongation modulus at (M _50), 100% elongation modulus at (M _{10 0),}
The breaking strength (T _B ) and the breaking elongation (E _B ) were measured.
The measurement was performed for one sample at N = 3, and the average value was used as the measured value. The results are summarized in Table 1. In addition, four pieces of the above cured product having a thickness of 3 mm are overlapped, and S
MoreA hardness was measured. The measurement was performed five times, and the average value was used as the measured value. Table 1 shows the results. <Curing time> According to Table 1, when PtVTS was used as the curing catalyst, the curing time of the methallyl-terminated polymer was slightly longer than that of the allyl-terminated polymer, but the difference was small (Example 1 and Comparative Example 1). Comparison, comparison of Examples 2 and 3 with Comparative Example 2, comparison of Example 6 with Comparative Example 3). On the other hand, when chloroplatinic acid is used as a catalyst, the curing is significantly slowed with a methallyl-terminated polymer. <Mechanical strength> Table 1 shows a comparison between Example 1 and Comparative Example 1, a comparison between Examples 2 and 3 and Comparative Example 2, and a comparison between Example 6 and Comparative Example 3.
It is clear from the comparison that the modulus and hardness of the cured product are improved by replacing the terminal structure with an allyl group with a methallyl group having the same main chain skeleton. From the comparison of Examples 3, 4, and 5, it is clear that the breaking strength and elongation improve as the molecular weight of the main chain skeleton increases. Further, from the comparison between Examples 2 and 3, it is found that by introducing the methallyl group in two stages, the modulus and hardness of the cured product are improved.

[0068]

In the present invention, a polymer having an alkenyl group of the general formula 1 or 2 at the terminal is used as the component (a), and a conjugate base of a strong acid as a ligand is used as a curing catalyst for the component (c). By using a platinum complex that does not contain the compound, a cured product having improved mechanical strength can be obtained without impairing the rapid curability at a high temperature, which is a characteristic of a curing system using hydrosilylation.

Continued on the front page F term (reference) 4F070 AA06 AA12 AA32 AA52 AC25 AC52 AC67 AE08 GA01 GC06 4J002 AA03W AC11W BB20W CH05W CP04X CP12W CP16W CP18W EE047 EX006 EX007 FD14X FD146 GH00 GJ01 AM02AQ02AQ02AQ02AQ02PQ AS03P AS03Q AS07P CA01 CA04 CA31 HA03 HA35 HA53 HA55 HA62 HC29 HC34 HC39 HC51

Claims (9)

[Claims] (A) General formula 1 or 2: H ₂ C = C (R ¹ )-(1) HC (R ¹ ) = CH- (2) (wherein R ¹ is a carbon atom having 10 or less carbon atoms) A polymer having an alkenyl group at the terminal represented by (hydrogen group), (b) 2
A curable composition comprising, as essential components, a compound having at least two hydrosilyl groups, and (c) a platinum complex catalyst containing no conjugate base of a strong acid as a ligand. 2. The curable composition according to claim 1, wherein R ¹ is a methyl group. 3. The curable composition according to claim 1, wherein the platinum complex is a platinum-vinylsiloxane complex. 4. The method according to claim 1, wherein the platinum complex is platinum-1,3-divinyl-
1,1,3,3-tetramethyldisiloxane complex or platinum-1,3,5,7-tetravinyl-1,3,5,7
The curable composition according to claim 1, which is a tetramethylcyclotetrasiloxane complex. 5. The curable composition according to claim 1, wherein the main chain of the polymer as the component (a) is a polyether polymer. 6. A polyether polymer having a molecular weight distribution measured by size exclusion chromatography of 1.6 or less,
The curable composition according to claim 5, having a molecular weight of 3,000 to 50,000. 7. The curable composition according to claim 5, wherein the component (a) is a polymer obtained by subjecting a hydroxyl group-terminated polyether to a Williamson ether synthesis reaction divided into two or more times. object. 8. The curable composition according to claim 1, wherein the main chain of the polymer as the component (a) is a hydrocarbon polymer. 9. The curable composition according to claim 1, wherein the main chain of the polymer of the component (a) is a (meth) acrylic polymer.