JP2927892B2 - Curable composition - Google Patents

Description

The present invention relates to a curable composition, and more specifically, to (A)
An acrylate polymer or a polyester polymer containing at least one alkenyl group in the molecule,
The present invention relates to (B) a polyorganohydrogensiloxane having at least two hydrogen atoms bonded to silicon atoms in a molecule, and (C) a curable composition containing a hydridylation catalyst as an essential component.

[Conventional technology and problems]

Conventionally, various curable liquid compositions which are cured to generate a rubber-like substance have been developed. Above all, as a curing system having excellent deep curing properties, polyorganosiloxanes having an average of two or more vinyl groups in one molecule at the terminal or in the molecular chain, and hydrogen atoms bonding to silicon atoms in one molecule. A crosslinkable polyorganohydrogensiloxane having two or more polyorganohydrogens has been developed, and is used as a sealing agent and a potting agent by utilizing its excellent weather resistance, water resistance and heat resistance. However, this system is limited in its use due to its high cost, poor adhesion, and easy mold generation. Furthermore, the above-mentioned polyorganosiloxane generally has poor compatibility with an organic polymer, and even if an attempt is made to cure the polyorganohydrogensiloxane and the organic polymer containing an alkenyl group, the polyorganohydrogensiloxane is not separated by phase separation. The hydrolysis and dehydrocondensation reaction of the compound are promoted, and there is a problem that sufficient mechanical properties cannot be obtained due to voids.

[Means for solving the problem]

The present invention solves these problems as a result of intensive studies in view of such circumstances, and provides a curable composition that is fast-curing, has excellent deep-curing properties, and has sufficient mechanical properties. . That is, when a specific polyorganohydrogensiloxane is used, the compatibility with an alkenyl group-containing organic polymer is good. Therefore, if both of the above components are cured using a hydrosilylation catalyst, a curable composition which is uniform, has excellent rapid curing and excellent deep curing properties, and has a cured product having sufficient mechanical properties such as tensile properties can be obtained. And arrived at the present invention.

That is, the present invention relates to a curable composition comprising the following components (A), (B) and (C) as essential components: (A) an acrylic ester-based polymer containing at least one alkenyl group in the molecule; (B) a polyorganohydrogensiloxane having at least two hydrogen atoms bonded to silicon atoms in the molecule; and (C) a hydrosilylation catalyst.

The acrylic ester polymer and the polyester polymer of the component (A) of the present invention are particularly preferred in that they have good compatibility with the component (B).

As the monomer component constituting the acrylate polymer, various acrylate monomers and other vinyl monomers can be used. Methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, sec.-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, tridecyl acrylate, stearyl Acrylate, cyclohexyl acrylate, benzyl acrylate, tetrahydrofurfuryl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, 2-phenoxyethyl acrylate, ethyl Carbitol acrylate, allyl acrylate, glycidyl acrylate, dimethylamino Acrylic acid and acrylic such as ethyl acrylate, acrylic acid, sodium acrylate, trimethylolpropane triacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and pentaerythritol triacrylate Acid ester monomer, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, propyl methacrylate, benzyl methacrylate, isopropyl methacrylate, sec. -Butyl methacrylate, 2-hydroxyethyl methacrylate Related, 2-
Hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, allyl methacrylate, ethylene glycol methacrylate, triethylene glycol methacrylate, tetraethylene glycol methacrylate, 1,3-butylene glycol methacrylate, trimethylolpropane methacrylate , 2-ethoxyethyl methacrylate, 2-methoxyethyl methacrylate,
Examples thereof include methacrylic acid and methacrylic acid ester monomers such as dimethylaminoethyl methyl chloride salt methacrylate, methacrylic acid, and sodium methacrylate. Further, in addition to the (meth) acrylic ester monomer, acrylamide, acrylonitrile, vinyl acetate, styrene, ethylene, propylene, isobutylene,
Vinyl monomers such as butadiene, isoprene and chloroprene can be used as the copolymer component.

Radical polymerization method, ionic polymerization method using one or more of the above monomer components in combination, G proposed by Du Pont
Various acrylate polymers can be obtained by a method such as the TP method (Group Transfer Polymerization). The polymer may be linear or branched.

The main chain skeleton constituting the polyester polymer is produced by polycondensing a polybasic acid and a polyhydric alcohol by a method such as a direct esterification method or a transesterification method. Specifically, the following components may be polycondensed, but the components are not limited thereto.

[Dihydric alcohol] Ethylene glycol, propylene glycol, butanediol, hexamethylene glycol, hydrogenated bisphenol A, neopentyl glycol, polybutadiene diol, diethylene glycol, triethylene glycol, dipropylene glycol [Trihydric or higher polyhydric alcohol] glycerin , Trimethylolmethane, trimethylolpropane, pentaerythritol [divalent carboxylic acid] phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, tetrachlorophthalic acid, polybutadienedicarboxylic acid, oxalic acid, malonic acid,
Succinic acid, adipic acid, sebacic acid, maleic acid, fumaric acid, cyclopentanedicarboxylic acid [trivalent or higher polycarboxylic acid] trimellitic acid, butanetricarboxylic acid, pyromellitic acid, and anhydrides and acyl halides of the above carboxylic acids And the like can be used in the same manner as the polyvalent carboxylic acid.

The main chain skeleton of the polymer can also be produced by ring-opening polymerization of lactone. Examples of the lactone include β-propiolactone, bivalolactone, α-methyl-β-propiolactone, δ-valerolactone, methyl-δ-valerolactone, dimethyl-δ-valerolactone, ε-caprolactone, and δ-methyl-. ε-caprolactone, dimethyl-ε-caprolactone and the like.

The polyester polymer may be linear or branched.

The alkenyl group of the component (A) is not particularly limited, but may have the formula (I) [R ¹ has the formula ^{-R 2 -, - R 3 -O} -R 4 -, (Wherein, R ² , R ³ , and R ⁴ are divalent hydrocarbon groups having 1 to 20 carbon atoms). R ⁵ is hydrogen or a methyl group; a is an integer of 0 or 1;

An alkenyl group represented by is preferred.

The molecular weight of the component (A) is preferably from 500 to 50,000, particularly preferably from 500 to 20,000, in consideration of the properties of the cured product and the compatibility with the component (B). The number of alkenyl groups is preferably 1 to 10 on average, more preferably 2 to 5 in one molecule. When a rubber-like cured product is prepared from the components (A), (B) and (C) of the present invention, the alkenyl group of the component (A) is located at the molecular end, so that the effective network chain length of the cured product is higher. It is preferable because it becomes longer.

As a method for introducing an alkenyl group into the acrylate polymer or polyester polymer of the component (A), various methods have been proposed.
The method can be broadly classified into a method of introducing an alkenyl group after polymerization and a method of introducing an alkenyl group during polymerization.

As a method for introducing an alkenyl group after polymerization, for example, a hydroxyl group, an alkoxide group,
An acrylate group-based polymer or a polyester-based polymer having a functional group such as a carboxyl group is reacted with an organic compound having an active group and an alkenyl group having reactivity with the functional group to terminate the alkenyl group, It can be introduced into the main chain or side chain. Examples of the organic compound having an active group and the alkenyl group reactive toward the functional groups are acrylic acid, methacrylic acid, vinyl acetate, acrylic acid chloride, unsaturated C ₃ -C _20, such as a bromide acrylate fatty acids, acid halides, acid anhydrides or allyl chloroformate _{(CH 2 = CHCH 2 OCOCl)} , C 3 -C 20 , such as allyl bromo formate (CH ₂ = CHCH ₂ OCOBr)
Unsaturated fatty acid-substituted carbonate halides, allyl chlorides,
Allyl bromide, vinyl (chloromethyl) benzene,
Allyl (chloromethyl) benzene, allyl (bromomethyl) benzene, allyl (chloromethyl) ether, allyl (chloromethoxy) benzene, 1-butenyl (chloromethyl) ether, 1-hexenyl (chloromethoxy)
Benzene, allyloxy (chloromethyl) benzene and the like can be mentioned.

As a method for introducing an alkenyl group during the polymerization, for example, when producing an acrylate polymer or a polyester polymer as the component (A) by a radical polymerization method, a radical such as allyl methacrylate or allyl acrylate is used in a molecule. By using a radical monomer having an alkenyl group having a low radical reactivity such as a vinyl monomer having an alkenyl group having a low reactivity or allyl mercaptan, an alkenyl group can be introduced into the main chain or terminal of the polymer.

The polyorganohydrogensiloxane as the component (B) of the present invention acts as a crosslinking agent for the acrylate or polyester polymer containing an alkenyl group in the molecule as the component (A). In order for the cured product to have a three-dimensional crosslinked structure, it is necessary to have at least two hydrogen atoms bonded to silicon atoms per molecule.
As the polyorganohydrogensiloxane, commercially available ones can be widely used. In particular, when a polyorganohydrogensiloxane having good compatibility with the component (A) is used, the polyorganohydrogensiloxane rapidly cures and has excellent uniformity in deep part curability. A cured product can be obtained. The number of silicon atoms in one molecule of the component (B) is in the range of 3 to 20, preferably 4 to 10. If the number of silicon atoms is less than 3, the heat resistance and weather resistance of the cured product will deteriorate, and conversely, as the number of silicon atoms increases, the alkenyl group-containing acrylate polymer or polyester component (A) will be used. The compatibility with the polymer becomes extremely poor, and a uniform cured product cannot be obtained. The skeleton of the polyorganohydrogensiloxane is preferably linear or cyclic because of its good compatibility.

Specific examples of the component (B) satisfying the above conditions include the following compounds.

a The following equation: (P and q are integers, 2 ≦ p + q ≦ 18, 2 ≦ p ≦ 18, 0 ≦ q ≦ 1
6) A linear polyorganohydrogensiloxane represented by: b: (P and q are integers, 1 ≦ p + q ≦ 18, 0 ≦ p ≦ 17, 1 ≦ q ≦ 1
8) A linear polyorganohydrogensiloxane represented by the following formula c: (P and q are integers, 3 ≦ p + q ≦ 20, 2 ≦ p ≦ 19, 1 ≦ q ≦ 1
8) Cyclic polyorganohydrogensiloxane represented by: Among the polyorganohydrogensiloxanes having the structures represented by a, b, and c above, particularly, the following formula: (P is an integer of 2 to 5), or a linear polyorganohydrogensiloxane represented by the following formula: (P and q are integers, 3 ≦ p + q ≦ 5, 3 ≦ p ≦ 5, 0 ≦ q ≦
The cyclic polyorganohydrogensiloxane represented by 2) is preferable in that it has excellent compatibility with the alkenyl group-containing acrylate polymer or polyester polymer as the component (A).

The hydrosilylation catalyst which is the component (C) of the present invention is not particularly limited, and any catalyst can be used.

Practical examples include a simple substance of platinum, alumina, silica, solid platinum supported on a carrier such as carbon black, chloroplatinic acid, a complex of chloroplatinic acid with alcohol, aldehyde, ketone, etc., platinum-olefin Complex {for example, Pt (CH ₂ CHCH ₂ ) ₂ (PPh ₃ ) ₂ Pt (CH ₂ CHCH ₂ ) ₂ C
l ₂ {; platinum-vinylsiloxane complex}, for example, Pt _n (ViM
e ₂ SiOSiMe ₂ Vi) _m , Pt [(MeViSiO) ₄ ] _m };
Phosphine complexes {eg, Pt (PPh ₃ ) ₄ , Pt (PB
u _{3) 4};} platinum - phosphite complex {for example, Pt [P
(OPh ₃ ] ₄ , Pt [P (OBu) ₃ ] ₄ } (wherein Me represents a methyl group, Bu represents a butyl group, Vi represents a vinyl group, Ph represents a phenyl group, and n and m represent integers) Dichloroplatinum, and also platinum-hydrocarbon complexes described in Ashby U.S. Pat. Nos. 3,159,601 and 3,139,662; and Lamoreaux U.S. Pat. No. 3,209,972.
Also included are the platinum alcoholate catalysts described in the specification. Further, the platinum chloride-olefin complex described in Modic U.S. Pat. No. 3,516,946 is also useful in the present invention.

Examples of catalysts other than platinum compounds include RhCl (PP
_{h 3) 3, RhCl 3,} Rh / Al 2 O 3, RuCl 3, IrCl 3, FeCl 3, AlCl 3, PdCl 2
_{· 2H 2 O, NiCl 2,} TiCl 4 , and the like. These catalysts may be used alone or in combination of two or more.
From the viewpoint of catalytic activity, chloroplatinic acid, platinum-olefin complex,
Platinum-vinylsiloxane complexes are preferred.

The molar ratio of the hydrosilyl group to the alkenyl group of the component (A) and the component (B) is preferably 0.2 to 5.0, more preferably 0.2 to 5.0.
4-2.5 is particularly preferred. When the molar ratio is less than 0.2, only a low-strength cured product with insufficient tackiness and tackiness is obtained, and when the molar ratio is greater than 5.0, 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 amount of the component (C) is not particularly limited, but is preferably in the range of 10 ^-1 to 10 ^-8 mol per ¹ mol of the alkenyl group in the component (B). Preferably, it is used in the range of 10 ^-3 to 10 ^-6 mol.

If the components (A), (B) and (C) of the present invention are mixed and cured, a uniform cured product having excellent deep curability can be obtained without a phenomenon such as foaming. The curing conditions are not particularly limited, but are generally 0 to 200 ° C, preferably 30 to 150 ° C.
For 10 seconds to 4 hours. Particularly, at a high temperature of 80 to 150 ° C., a composition which cures in a short time of about 10 seconds to 1 hour can be obtained. The properties of the cured product depend on the molecular structure of the components (A) and (B) used, the main chain skeleton and molecular weight of the polymer, etc.
It can be manufactured from a rubber-like thing to a resin-like thing.

When preparing a cured product, (A), (B) and (C)
In addition to the three essential components, a solvent, an adhesion improver, a physical property modifier, a storage stability improver, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, and a metal deactivator according to the purpose of use. Various additives such as an ozone deterioration inhibitor, a light stabilizer, an amine radical chain inhibitor, a phosphorus peroxide decomposer, a lubricant, a pigment, and a foaming agent can be appropriately added.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Synthesis Example 1 115.72 g of n-butyl acrylate, 60.00 g of methyl methacrylate, 20.16 g of allyl methacrylate, 6.46 g of n-dodecyl mercaptan, 2.0 azobisisobutyronitrile
g, a toluene solution of an alkali ester monomer consisting of 400 ml of toluene was dropped into a flask in which 50 ml of toluene was refluxed from a dropping funnel under a nitrogen atmosphere over about 2 hours. After the completion of the dropwise addition, the reaction was further continued for 2 hours. The reaction solution was evaporated and further dried under reduced pressure at 80 ° C. for 3 hours to obtain about 195 g of a pale yellow viscous liquid oligomer. The number of moles of the allyl group by iodine titration was 0.0818 mol /
The molecular weight by 100 g, VPO was 2950, indicating that an average of 2.4 allyl groups were introduced per molecule.

Synthesis Example 2 300 g (0.1 mol) of terminal hydroxyl group polycaprolactone (number average molecular weight 3000, hydroxyl equivalent 1500), 24.0 g of pyridine, 300 ml of THF were equipped with a stirring rod, a thermometer, a dropping funnel, a nitrogen blowing tube, and a cooling tube. Into a round bottom flask
At room temperature, 32 g of allyl chloroformate was gradually dropped from the dropping funnel. Thereafter, the mixture was heated to 50 ° C. and stirred for 3 hours. After removing the generated salt by filtration, 150 ml of toluene was added, and 200 ml of toluene was added.
Allyl-terminated polycaprolactone was obtained by washing with an aqueous hydrochloric acid solution, neutralization and concentration. VPO measurement of the obtained oligomer showed that the number average molecular weight was 3,200. 300MHz N
The introduction of the allyl group was confirmed from the spectrum of the olefin portion of the MR. From the determination of the olefin by iodine titration, an average of 1.83 allyl-type unsaturated groups (0.0573
mol / 100g) was introduced.

Example 1 In order to examine the compatibility between an allyl group-containing acrylate polymer produced in Synthesis Example 1 and various polyorganohydrogensiloxanes, the organic polymer was used in combination as shown in Table 1. A predetermined amount of the coalesced and 0.1 g of the siloxane were mixed well, and the mixed state was observed after centrifugal defoaming. First result
As shown in the table, although some of them were slightly cloudy, they were almost transparent and uniform. The siloxane was found to have good compatibility with the organic polymer.

Then chloroplatinic acid catalyst solution to the above each mixture in order to examine the curable (the _{H 2 PtCl 6 · 6H 2 O} 1.0g C 2 H 5 OH 1ml, solution in dimethoxyethane 99 ml) often adding a predetermined amount Mixed. A part of the mixture was subjected to a gelation tester (Nissin Kagaku Co.
) And snap-up time (time until rubber elasticity) was measured at a predetermined temperature. The results are shown in Table 1, and it was found that the composition was high-temperature fast-curing.

Example 2 Compatibility and curability were examined in the same manner as in Example 1 except that the polyester polymer produced in Synthesis Example 2 was used instead of the acrylate polymer produced in Synthesis Example 1. Table 2 shows the results. As in the case of Example 1, the siloxane was found to have good compatibility with the organic polymer.

Example 3 A predetermined amount of the acrylic group-containing polyester polymer produced in Synthesis Example 2, a predetermined amount of each of the various polyorganohydrogensiloxanes, and the chloroplatinic acid catalyst solution used in Example 1 in the proportions shown in Table 3 Mix well with stirring. The mixture was defoamed by centrifugation and poured into a polyethylene mold. After defoaming again at room temperature under reduced pressure, the mixture was cured at 100 ° C. for 1 hour to obtain a uniform rubbery cured product having a thickness of about 3 mm. A No. 3 dumbbell compliant with JIS K 6301 was punched out of the sheet of the cured product, and a tensile test was performed at a tensile strength of 200 mm / min. The results are shown in Table 3.

From Table 3, it was found that the composition of the present invention can be cured in a short time to produce a uniform rubbery cured product.

Comparative Example 1 Instead of the polyorganohydrogensiloxane used in the examples, the following formula A predetermined amount of polymethylhydro-dimethylsiloxane copolymer having a high molecular weight (average molecular weight of about 2,000 to 2,100, PS 123 manufactured by Chisso Corporation) represented by the formula (mol of allyl group in each organic polymer and hydrosilyl group of PS 123) An attempt was made to produce a cured product in the same manner as in Example except that the ratio was set to 1.) Each of the organic polymers having an allyl group and the polysiloxane had poor compatibility and became turbid during mixing. Some of them were separated when left for a long time. Even after defoaming under reduced pressure, there was a lot of foaming, and only a cured product having poor mechanical properties with many foams mixed therein was obtained.

[Action / Effect]

The composition of the present invention can provide a uniform cured product that has good mechanical properties, is fast-curing, and is also excellent in deep-section curability.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kazuya Yonezawa 5-12-11 Tsutsujigaoka, Tarumizu-ku, Kobe-shi, Hyogo (56) References JP-A-2-45566 (JP, A) JP-A-1-221457 (JP) , A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 1/00-101/14

Claims (4)

(57) [Claims] 1. A curable composition comprising the following components (A), (B) and (C) as essential components: (A) an acrylate polymer containing at least one alkenyl group in the molecule Or (B) a polyorganohydrogensiloxane having at least two hydrogen atoms bonded to silicon atoms in the molecule, and (C) a hydrosilylation catalyst. 2. The acrylate polymer or polyester polymer of the component (A) is a compound of the formula (I) [R ¹ has the formula ^{-R 2 -, - R 3 -O} -R 4 -, (Wherein, R ² , R ³ , and R ⁴ are divalent hydrocarbon groups having 1 to 20 carbon atoms). R ⁵ is hydrogen or a methyl group; a is an integer of 0 or 1; The composition according to claim 1, wherein the composition has at least one alkenyl group represented by the following formula, and has a molecular weight of 500 to 50,000. 3. An alkenyl group-containing acrylate polymer or polyester polymer as the component (A) and (B)
3. The composition according to claim 1, which has good compatibility with the components. 4. The composition according to claim 1, wherein the polyorganohydrogensiloxane component (B) is at least one selected from the following compounds. (P and q are integers, 2 ≦ p + q ≦ 18, 2 ≦ p ≦ 18, 0 ≦ q ≦ 1
6) (P and q are integers, 1 ≦ p + q ≦ 18, 0 ≦ p ≦ 17, 1 ≦ q ≦ 1
8) (P and q are integers, 3 ≦ p + q ≦ 20, 2 ≦ p ≦ 19, 1 ≦ q ≦ 1
8)