JPH03294356A - Curing type composition - Google Patents

Abstract

PURPOSE:To obtain a curing type composition suitable as sealing material, adhesive, etc., having no reduction in elasticity during high temperature expo sure, showing excellent durability, by blending a polysulfide polymer with spe cific amounts of an oxidizing agent and a specific compound. CONSTITUTION:(A) 100 pts.wt. polysulfide polymer or 100 pts.wt. polymer com prising 5wt.% polysulfide polymer and a thiol group-containing polyether poly mer which contains -(R1O)n- (R1 is 2-4C alkylene; n is 6-200) and disulfide bond in the main chain and thiol group at the end and has a ratio of sulfur/mercaptan in the polymer of >=1.06 is blended with (B) 1-50 pts.wt. oxidizing agent and (C) 0.5-50 pts.wt. one or more compounds selected from C1: C=C bond-containing compound, C2: nitrogen-containing heterocyclic and/or aromatic amine, C3: phosphonic ester compound, etc.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a curable composition, which provides a cured product with good durability without loss of elasticity, especially when exposed to high temperatures, and which can be used as a sealant, adhesive, etc. The present invention relates to a curable composition suitable for use as a curable composition.

[Conventional technology]

Polymers containing two or more thiol groups in one molecule easily react with oxidizing agents to increase their molecular weight and become cured products, so they are used in sealants, paints, adhesives, etc. .

Among these thiol group-containing polymers, U.S. Pat.
．． The polysulfur and ido polymers described in No. 466,963 have been used as raw materials for sealing materials for many years because they have excellent oil resistance, chemical resistance, flexibility, and the like.

In addition, the polysulfide polymer and thiol-based composition has good compatibility with general-purpose inexpensive plasticizers,
In addition, by reducing the amount used, the coating film will not harden even if the coating is applied to the cured product, making it suitable as a sealing material.

[□Problem that the invention seeks to solve]

However, when a cured product obtained by curing a polysulfide polymer or a polymer made by mixing a polysulfide polymer and a thiol group-containing polyether polymer with an oxidizing agent becomes rigid and loses elasticity when exposed to high temperatures of 80 or higher, There is a problem of poor durability.

Therefore, an object of the present invention is to provide a curable composition that exhibits less decrease in elasticity when exposed to high temperatures and provides a cured product with good durability.

[Means to solve the problem]

As a result of intensive research for the above purpose, the present inventors have discovered that a predetermined amount of a specific compound can be added together with an oxidizing agent to a polysulfide polymer or a polymer made by mixing a polysulfide polymer and a thiol group-containing polyether polymer. For example, the inventors have discovered that the elasticity does not decrease when exposed to high temperatures and the durability is significantly improved, and the present invention has been developed based on this finding.

That is, the curable composition of the present invention contains (A) 100 parts by weight of polysulfide polymer, (B) 1 to 50 parts by weight of an oxidizing agent, and (C) at least one selected from the following (1) to (v). 0.5 to 50 parts by weight per compound (i) Compound having a carbon-carbon double bond, (ii) Nitrogen-containing heterocyclic compound and/or aromatic amine, ω phosphonate ester compound, 00 hydrogen phosphonate (v) a thioether antioxidant;

Another curable composition of the present invention is (A) (a
) polysulfide polymer and (b) the main chain contains -(R,0), - (wherein R1 is an alkylene group having 2 to 4 carbon atoms, and n is an integer of 6 to 200), and a disulfide bond. , and a thiol group-containing polyether polymer having a thiol group at the top and a ratio of sulfur content/mercaptan content in the polymer of 1.06 or more, assuming (a) + (b) as 100% by weight. , (B>
1 to 50 parts by weight of an oxidizing agent, (C) 0.5 to 50 parts by weight of at least one compound selected from the following (i) to (v) (1) a compound having a carbon-carbon double bond, OL) It is characterized by containing a nitrogen-containing heterocyclic compound and/or an aromatic amine, (iii) a phosphonic acid ester compound, (10) a phosphonic acid hydrogen ester compound, and (v) a thioether antioxidant.

The present invention will be explained in detail below.

The polysulfide polymer (A) in the composition of the present invention is represented by the following general formula (1).

R3 (R, S-, R, SH... (1) In the above general formula, X is an integer from 1 to 5, and the average value is 2
It is. m is an integer from 1 to 50. Also, R3 is -C
H2CH2-1-C,11,0C2Hdi,-C,l(,
OCR, OC2)1. - An organic residue such as an alkylene group or an alkylene ether group such as -C, H, OC, 1(a-).

The polysulfide polymer of the present invention has fluidity at room temperature and has a molecular weight of 100 to 200,000, preferably
400 to 50,000.

Preferred examples of such polysulfide polymers are described in US Pat. No. 2,466,963.

Furthermore, in the present invention, a mixture of the above-mentioned (a) polysulfide polymer and (6) thiol group-containing polyether polymer can be used.

(b) Thiol group-containing polyether polymer in the present invention has -(R+0) as a polyether moiety in the main chain,
-Including. Here, R1 is an alkylene group having 2 to 4 carbon atoms,
n represents an integer of 6 to 200. The molecular weight of this polyether portion is preferably 400 to 10,000.

If the molecular weight is less than 400, the effect of improving compatibility with a plasticizer when mixed with a polysulfide polymer is small, and if it exceeds 10.000, the viscosity of the polymer increases, which is not preferable.

Further, this thiol group-containing polyether polymer contains a disulfide bond in the main chain, has a thiol group at the end, and has a weight ratio of sulfur content/mercaptan content of 1.06 or more. When the ratio of sulfur content/mercaptan content is less than 1.06, the proportion of disulfide bonds is small and the compatibility with the polysulfide polymer is poor.

Preferred examples of such thiol group-containing polyether polymers include those synthesized by the known method described in Japanese Patent Publication No. 47-48279. That is, by adding an epihalohydrin such as epichloro, hydrin, or epibromohydrin to a polyalkylene glycol such as polypropylene glycol or polyethylene glycol, and then reacting it with an alkali hydrosulfide such as sodium hydrosulfide or potassium hydrosulfide, the following general formula ( A polyether polymer having a functional group as represented by 2) is obtained.

(CH2CH-0), -CIl, -CH-C)12-
3H... ・(2) R30ft (However, R3 is hydrogen or a methyl group, and p is 6 to 20
It is an integer of 0. ) The main chain of the polymer thus obtained contains -8 disulfide bonds, and is suitable as the thiol group-containing polyether polymer of the present invention.

When (a) polysulfide polymer and (b) thiol group-containing polyether polymer are mixed, the content of polysulfide polymer is 5% by weight or more, with (a)+(b) being 100% by weight. If the amount of polysulfide polymer is less than 5% by weight of the whole, the weather resistance of the cured product will be poor. The preferred polysulfide polymer content is 5 to 95% by weight.

As the oxidizing agent in the present invention, substances conventionally used as curing agents for thiol group-containing polymers can be used. Specific examples of these oxidizing agents include ZnL, FeL,
Pb0a, MgL, CaL, BaL, MnL, TeO2
, 5e02, Pb30. ．． Inorganic peroxides such as 5rOz, LiaOa, ZnO, Fen, PbO, FezOa
, 5b2o3 , MgO1CoO1CaO1CuO1B
Inorganic oxides such as aO, Na2CrO4, zcrL, N
azCr20t, KaCraOt, NaCj! U4,
NaBL +H2O2, K2C,0,, KMnOa,
Inorganic oxidizing agents such as sodium percarbonate (2NazCO313H20□), benzoyl peroxide, dicumyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, t-butyl perbenzoate,
Examples include organic peroxides such as sodium peracetate and urea peroxide, and organic oxidizing agents such as nitrobenzene, dinitrobenzene, and baraquinone dioxime, but PbO7 is most widely used. In the composition of the present invention, the blending amount of these oxidizing agents varies depending on the type of oxidizing agent, but for boat fishing,
Polysulfide polymer (when mixing a thiol group-containing polyether polymer, a mixture of polysulfide polymer and thiol group-containing polyether polymer)
The amount is 1 to 50 parts by weight per 100 parts by weight.

Specific compounds (C) to be added to the composition of the present invention include (i) a compound having a carbon-carbon double bond, (ii) a nitrogen-containing heterocyclic compound and/or aromatic amines, and phosphonic acid. (iii) a phosphonic acid hydrogen ester compound, and (v) a thioether antioxidant.

Here, (i) the compound having a carbon-carbon double bond is an unsaturated ester, an unsaturated carboxylic acid, an unsaturated amine, etc., and preferably the carbon-carbon double bond is other than an ester in the molecule. It is a compound with a structure that is not conjugated with carbon-carbon double bonds such as , carbonyl, and carboxyl groups. Such compounds include oleyl oleate, octyl oleate, methyl 12-acetyl ricinoleate, 2-n
Examples include dimethyl -hexyltrideceneniate, trioleyl phosphate, oleic acid monoglyceride, dioleyl ivate, oleic acid, and the like.

(ii) Among the nitrogen-containing heterocyclic compounds and/or aromatic amines, the nitrogen-containing heterocyclic compound has at least one nitrogen atom contained in the molecule constituting an aromatic ring, and 2 .2.4-)! Examples include J methyl-1,2-dihydroquinoline, 6-nitoxy-2.2.4-) dimethyl-1,2-dihydroquihane, etc. Aromatic amines include at least one amino group bonded to an aromatic ring. It is preferred that the amino group has one or more alkyl groups. Such aromatic amines include N
-phenyl-N'-isopropyl-p-phenyl diamine and the like.

(iii) Examples of the phosphonic acid ester compound include 2-ethylhexylphosphonic acid-di-2-ethylhexyl ester.

As the 00 phosphonic acid hydrogenated ester compound, for example, 2
-Ethylhexylphosphonic acid-mono 2-ethylhexyl ester and the like.

(v) Examples of the thioether antioxidant include pentaerythritoltetra [toalkyl (C1, to C16) thiopropionic acid ester].

Only one type of the above compounds (i) to (v) may be added, but two or more types may be mixed and added as required.

In the composition of the present invention, one of the above compounds (i) to (v)
The blending amount of the species or two or more species is 0.5 to 50 parts by weight, preferably 1 to 30 parts by weight, based on 100 parts by weight of the polymer (A) (polysulfide polymer alone or the total of it and polyether polymer). Department. If the amount of the compound is less than 0.5 parts by weight, the effect of suppressing a decrease in elasticity and improving durability when exposed to heat at 80° C. or higher is poor, while if it exceeds 50 parts by weight, the compounding cost becomes high.

The curable composition of the present invention further includes the following for the purpose of improving economic efficiency, workability when applying the composition, and physical properties after curing.
Fillers such as calcium carbonate, talc, clay titanium oxide, silica, etc. can be added. Furthermore, esters such as dioctyl phthalate (DOP) and diheptyl phthalate (DHP) can be added to the curable composition of the present invention. Plasticizers such as chlorinated paraffin and hydrogenated terphenyl can also be added.

〔Example〕

The present invention will be explained in further detail by the following examples.

Synthesis Example 1 Difunctional polypropylene glycol obtained by adding propylene oxide to propylene glycol (OH value 162 HOOOg, 294.4 g of shrimp chlorohydrin, and 2.0 g of stannic chloride trihydrate) It was charged into a reaction vessel and stirred at 110°C for 3 hours.
．． Add 6g of sodium hydrogen sulfide (purity 70%) and heat to 100℃
and stirred for 1.5 hours.

Thereafter, the salt was removed to obtain a pale yellow transparent liquid polymer. When the obtained polymer and polysulfide polymer (trade name "Thiokol LP55" manufactured by Toshi Thiokol ■) were mixed at a weight ratio of 1/1, the mercaptan content was 3.5.
% and a viscosity of 60 poise (25° C.), a brown transparent polymer was obtained.

Base material A was obtained by blending a plasticizer and a filler with the polymer obtained in Synthesis Example 1 in the proportions shown in Table 1. Also lead peroxide and plasticizer,
A curing agent A was obtained by blending a vulcanization aid and a filler in the proportions shown in Table 2. The base material A and curing agent A were mixed with various compounds (C) shown in Table 3, and a tensile adhesion test was conducted using an aluminum plate as an adherend in accordance with JIS^-5758. The curing conditions were 50℃ and 7 days.
Furthermore, similar tests were conducted on those heated at 90° C. for 14 days.

On the other hand, as Comparative Example 1, similar tests were conducted on a formulation using only base agent A and curing agent A without adding compound (0). The results are shown in Table 4.

Table 1 Table 2 Composition of main ingredient A Composition of curing agent A Table 3 Compound (C) Table 4 Tensile adhesion test results Examples 15 to 19 and Comparative Example 2 Polysulfide polymer (manufactured by Toshi Thiokol ■, product A base material B was obtained by blending a plasticizer and a filler in the proportions shown in Table 5. Further, a hardening agent B was obtained by blending lead peroxide and a plasticizer in the proportions shown in Table 6.

To this base agent B and curing agent B, various compounds shown in Table 7 (
The same test as in Example 1 was conducted on the mixture of C). Further, as Comparative Example 2, similar tests were conducted on a formulation using only base agent B and curing agent B without adding compound (0). The results are shown in Table 8.

Table 5 Table 6 Composition of main ingredient B Table 7 Compound of curing agent B Compound (C) [Effects of the invention] As detailed above, the curable composition of the present invention can be used even when exposed to high temperatures of 80°C or higher. To provide a cured product with a small decrease in elasticity and dramatically improved durability.

Such a curable composition is extremely suitable for use in sealants and the like.

Applicant Toray Thiokol Co., Ltd. Representative Patent Attorney Taka Ishibashi Ma Table 8 Results of tensile adhesion test

Claims (3)

[Claims] (1) (A) 100 parts by weight of polysulfide polymer, (B) 1 to 50 parts by weight of an oxidizing agent, and (C) 0.5 to 0.5 parts by weight of at least one compound selected from the following (i) to (v). 50 parts by weight (i) compound having a carbon-carbon double bond, (ii) nitrogen-containing heterocyclic compound and/or aromatic amines, (iii) phosphonic acid ester compound, (iv) phosphonic acid hydrogen ester compound, (v) a thioether antioxidant; a curable composition comprising: (2) (A) (a) Polysulfide polymer, and (b) -(R_1O)_n- in the main chain (wherein R_1 is an alkylene group having 2 to 4 carbon atoms, and n is an integer of 6 to 200. ), and a thiol group-containing polyether polymer containing a disulfide bond and a thiol group at the end, and in which the ratio of sulfur content/mercaptan content in the polymer is 1.06 or more, (a) + (b ) is taken as 100% by weight, and (B) is added to 100 parts by weight of a polymer containing 5% by weight or more of (a).
1 to 50 parts by weight of an oxidizing agent; (C) 0.5 to 50 parts by weight of at least one compound selected from the following (i) to (v); (i) a compound having a carbon-carbon double bond; (ii) ) a nitrogen-containing heterocyclic compound and/or aromatic amines, (iii) a phosphonic acid ester compound, (iv) a phosphonic acid hydrogen ester compound, and (v) a thioether antioxidant. Curable composition. (3) In the curable composition according to claim 1 or 2,
The compound (i) of the compound (C) having a carbon-carbon double bond is one or more selected from unsaturated carboxylic acids, unsaturated esters, and unsaturated amines. Curable composition.