JPS62119254A - Curable composition - Google Patents

Abstract

PURPOSE:The titled composition, obtained by polymerizing an acrylic acid or methacrylic acid ester in the presence of a specific silane compound and radical polymerization initiator, having improved light, weather and heat resistance, etc., and suitable for coating materials, adhesives, etc. CONSTITUTION:A curable composition obtained by polymerizing (A) an acrylic acid or methacrylic acid ester expressed by formula I (R is H or CH3; R1 is 1-8C alkyl), e.g. methyl acrylate, etc., in the presence of (B) a silane compound expressed by formula II (R2 is methoxy, etc.; R3 is 1-4C alkyl; a is 0, 1 or 2; X is chloro or bromo) as a chain transfer agent, e.g. methyldiethoxysilane, and (C) a radical initiator 2,2'-azobisisobutyronitrile, etc. The amount of the silane compound to be used is within 0.005-0.1mol, preferably 0.01-0.5mol range based on 1mol component (A).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to curable compositions, in particular lightfastness,
The present invention relates to a moisture-curable copolymer composition that has excellent weather resistance, heat resistance, durability, and stain resistance, and is useful as a paint, adhesive, or injection agent.

Curable polymers (acrylic and methacrylic) into which various functional groups have been introduced are in practical use as resin components for paints, adhesives, and the like. However, although it is expected that silicone-based polymers will emerge with high light resistance, weather resistance, and practicality, there have been only a few attempts to introduce silicone polymers using copolymerization or croup transfer polymerization. It's just that.

As a result of intensive research into polymers into which alkoxysilyl groups have been introduced and their practical utility, the present inventors have discovered that certain acrylic ester It i forms or methacrylic ester forms [hereinafter collectively referred to as (meth)acrylic esters] When ester monolayer] is polymerized in the presence of a specific silane compound as a chain transfer agent and a common radical initiator, the resulting polymer has alkoxy or halogen silyl groups at both ends of its molecular chain, paints, adhesives,
It was discovered that the present invention could be applied to injections, and the present invention was completed.

That is, the present invention provides the formula (1): C■-I2=CRCOOR
(meth)acrylic acid ester represented by 1 [wherein k is i-I or CH3, and 1 is an alkyl group having 1 to 8 carbon atoms] 1. At least one type of ffi form is used as a (2) chain transfer agent, formula: % formula %
) [During the ceremony, Ai. is a methoxy or ethoxy group, R3 is an alkyl group having 1 to 4 carbon atoms, a is 0, 1 or 2, and X
is chloro or bromo] and (3) a polymer obtained by polymerization in the presence of a radical initiator. .

In addition, the (meth)acrylic acid ester monomer (1) (CH2=CR) in the polymer, the silane compound 0OR
1 Indicator + 3) (The reaction chain mechanism of It is thought that the process will proceed as follows. .

Examples of the (meth)acrylic acid ester 1ti71 body (1) used in the present invention include methyl acrylate, ethyl acrylate, propyl acrylate'), n
-butyl acrylate, imbutyl acrylate, amyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, n
-octyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, inbutyl methacrylate, 2-ethylhexyl methacrylate, etc., and at least one of these is used. A methacrylic acid ester #mer is preferable since it does not impart rubber elasticity to the target composition but rather forms a hard film. Monomers that can be copolymerized as necessary for these essential bodies include, for example, lacryl methacrylate,
tridecyl methacrylate, benzyl methacrylate,
Cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycidyl methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, glycidyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl Acrylate, methacrylic acid, acrylic acid, vinyl acetate, vinyl propionate, vinyl persatate (product name Beova, manufactured by Shell Chemical), vinyl chloride, acrylonitrile, styrene, acrylamide,
Examples include N-methylolacrylic acid amide, vinylpyridine, maleic anhydride, vinylpyrrolidone, butadiene, and the like.

The silane compound (2) used in the present invention functions as a chain transfer agent and also serves as a reaction component to introduce alkoxy or halogen silyl groups at both ends of the molecular chain of the resulting polymer. Examples of such silane compounds include methyljethoxysilane, dimethylethoxysilane, triethoxysilane, dimethylmethoxysilane, methyldimethoxysilane, trimethoxysilane, ethyljethoxysilane, diethylethoxysilane, ethyldimethoxysilane, diethylmethoxysilane, propyl Examples include jetoxysilane, propyldimethoxysilane, dipropylethoxysilane, dipropylmethquinsilane, butyljethoxysilane, butyldimethoxysilane, dibutylethoxysilane, dibutylmethoxysilane, tetrachlorosilane, and tetrabromosilane, and one of these Or use two or more types.

The radical initiator (3) used in the present invention includes those used in ordinary bulk polymerization and solution polymerization, such as 2,2'-azobisinbutyronitrile (AIBN).
, 2,2'-azobisisovaleronitrile, 2.2'-
Azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, [-butyroperoxide, methyl ethyl ketone peroxide, etc., as well as redox catalysts (transition metal salts, amines, etc.) used in redox polymerization and peroxide radical initiation Combinations of agents may be employed.

In the presence of the above-mentioned silane compound (2) and radical initiator (3), the polymer which is the main component of the curable composition according to the present invention is prepared by adding (meth)acrylic acid ester ZLMt body + 1 alone or in addition to other polymers. It is produced by radical polymerization in combination with polymerizable monomers using conventional methods (bulk polymerization, solution polymerization, etc.) and conditions.

In order to prevent gelation during the above polymerization, formula: % formula %) [In the formula, R4 is a divalent hydrocarbon group, R5 is a carbon number of 1 to 4
a methoxy or ethoxy group, and b is 0, 1 or 2] can be used. In addition, in order to further improve the cured physical properties of the obtained polymer (particularly to obtain a tough cured product), the formula: %Formula%) [In the formula, R7 is an alkyl group having 1 to 4 carbon atoms, and R8 is methoxy or ethoxy group, and C is 0, 1 or 2. : [In the formula, R9 is H or CH3, Rlo is a divalent hydrocarbon group, R1□ is an alkyl group having 1 to 4 carbon atoms, R12 is a methoxy or ethoxy group, and d is 0°1 or 2] (meth)acryloxyalkoxysilane [e.g. "-(meth)acryloxypropyltrimethoxysilane, r-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ- (meth)acryloxypropylmethyljethoxysilane, etc.] may be copolymerized in an appropriate amount.

The above (meth)acrylic acid ester 1! The ratio of the silane compound (1) to the silane compound (2) is usually 0.005 to 0.1, preferably 0.01 to 0, per 1 mole of the (meth)acrylic acid ester. .05
You can select by mole. The proportion of the silane compound is 0.
If the amount is less than 0.005 mol, the viscosity of the resulting polymer will be high, and the curability of the polymer due to water or humidity will be insufficient. If the amount exceeds 0.1 mole, the cured physical properties of the polymer deteriorate and become brittle), which tends to make it uneconomical.

The polymer produced as described above has almost no stickiness after curing, is free from contamination due to adhesion of dust, and has excellent light resistance, weather resistance, and heat resistance, comparable to conventional silicone polymers. It is recognized that it has excellent properties and durability.

The curable composition according to the present invention is composed of the above polymer alone or by adding various additives for various uses. It can be used in paints, adhesives, and injection agents.

Next, the present invention will be specifically explained with reference to Examples.

Example 1 Methyl methacrylate 10 (1 (1 mol), -acryloxypropylmethyldimethoxysilane 0.127 (0
,005 mol), methyljethoxysilane 0.52(0
,0037 mol), toluene 150y (1,63 mol)
and 2,2'-azobis(2,4-dimethylvaleronitrile) 0.1'! (0,0004 mol) is placed in a four-tube flask equipped with a condenser, a stirrer, a thermometer, and a nitrogen inlet tube. This is polymerized while stirring on an oil bath at 60°C, and the viscosity of the contents increases in about 5 hours. After continuing polymerization for an additional 5 hours, the contents are allowed to cool to room temperature. The obtained polymerization solution was a somewhat viscous liquid, and the polymerization rate was 92.3% as determined by the following formula using the reduced pressure weight change method (non-volatile fraction method) at 105° C. for 3 hours.

Polymerization rate (%) This resin solution 207 contains 0.3 n-butyltin oxide.
The solution is coated on a glass plate to a thickness of about 0.05 mm and left in a room at 20° C. and 65% R) for 5 days. In this way, a cured film having a thickness of about 0.0:3 parts m is obtained. This film has good adhesion to glass, and
The pencil hardness according to ISK 5400 was 5 tI.

Example 2 50 g (o, 5 mol) of methyl methacrylate, 1 (0,15 mol) of 2-ethylhexyl methacrylate, 1 (0,156 mol) of butyl acrylate, 0. 12F
(0,005 mol), methyljethoxysilane 0.5
y (0,0037 mol), toluene 1ooy (i.63
mol) and 0.17 (0,0004 mol) of 2,2'-azobis(2,4-dimethylvaleronitrile) were polymerized for 8 hours in the same manner as in Example 1.

The polymerization rate by reduced pressure weight change method (non-volatile fraction method) is 90.1
%Met.

Add rutile type titanium white 207 to 50 g of this polymerization solution,
Furthermore, 20 parts of toluene and 30 parts of methyl ethyl ketone are added and uniformly dispersed with a sand mill.

The white image obtained in this way was added with 0.3 parts of fn-butyl tin oxide site, thinly coated on a polyethylene plate, and left in a room at 20°C and 65% [1] for 5 days. Obtain a film of 0.008 mm.

Regarding the above cured film, No. 3 dumbbell specified by JIS K-6301 and Shimabara Autograph DC5-5
When the physical properties were measured using JIS K-6301 using 000, the elongation was 150% and the cutting strength was 36~/
It was cIN. In addition, no surface deterioration or deterioration of physical properties of the composition was observed in heat aging at 100° C. for 168 hours and accelerated weathering tests in which the composition was irradiated for 500 hours using a Punya Ink Quasi-Ometer.

Claims (1)

[Claims] 1. Formula (1): CH_2=CRCOOR_1 [in the formula, R
is H or CH_3, and R_1 is an alkyl group having 1 to 8 carbon atoms. , tables, etc. ▼ or Si-(X)_4 [In the formula, R_2 is a methoxy or ethoxy group, R_3 is an alkyl group having 1 to 4 carbon atoms, a is 0, 1 or 2, and X is chloro or bromo. 1. A curable composition comprising as main components a silane compound represented by (3) and a polymer obtained by polymerization in the presence of a radical initiator. 2. The composition according to item 1 above, wherein the molar ratio of the (meth)acrylic acid ester monomer (1) to the silane compound (2) is 1/0.005 to 0.1.