JPH03250054A - Synthetic resin composition - Google Patents

Abstract

PURPOSE:To enable the production of a cured article exhibiting an excellent water resistance even at a low temp. by compounding a specific synthetic resin with a carbodiimide compd. CONSTITUTION:A synthetic resin having carboxyl groups and other functional groups reactive with carbodiimide linkages is prepd. by copolymerizing 0.5-50 pts.wt. alpha,beta-ethylenically unsatd. monomer having at least one functional group selected from the group consisting of hydroxyl, alkylol, and glycidyl groups [e.g. 2-hydroxyethyl (meth)acrylate], 0.1-30 pts.wt. carboxylated alpha,beta-ethylenically unsatd. monomer [e.g. (meth)acrylic acid], and 20-99.4 pts.wt. alpha,beta- monoethylenically unsatd. monomer [e.g. ethyl (meth)acrylate] in the presence of a radical polymn. initiator. 100 pts.wt. said synthetic resin is compounded with 0.1-50 pts.wt. carbodiimide compd. having 1-4 carbodiimide linkages.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a synthetic resin composition, and more particularly to a synthetic resin composition that provides a cured product with high density even at low temperatures.

[Conventional technology]

It has been reported in JP-A-59-18 that an aqueous resin composition consisting of a latex resin having only a carboxyl group as a functional group and a carbodiimide compound has relatively excellent low-temperature crosslinking properties.
It is described in Publication No. 7029.

[Problem to be solved by the invention]

However, the aqueous resin composition described in the above publication still has insufficient low-temperature crosslinking properties, and when crosslinked at low temperatures, a cured product with excellent water resistance could not be obtained.

[Means to solve the problem]

In view of the above-mentioned circumstances, the present inventors have conducted intensive studies to obtain a synthetic resin composition that provides a cured product with excellent water resistance even at low temperatures. The present invention was accomplished by discovering that a synthetic resin that also has a hydrophilic functional group provides a cured product that has superior water resistance and heat resistance even at low temperatures when cured with a carbodiimide compound, compared to a synthetic resin that only has a carboxyl group. reached.

That is, the present invention provides a synthetic resin composition comprising a synthetic resin (A) having a carboxyl group and a functional group other than the carboxyl group that can react with a carbodiimide bond, and a carbodiimide compound (B). It is. The synthetic resin (A) having a carboxyl group and a functional group other than the carboxyl group that can react with a carbodiimide bond in the molecule used in the present invention includes a carboxyl group and a hydroxyl group, an alkylol group, a glycidyl group, etc. There are no particular limitations on the synthetic resin as long as it has a functional group that can react with carbodiimide bonds, such as alkyd resins,
Polyester resin, urethane resin, epoxy resin, α,
Examples include polymers of β-ethylenically unsaturated monomers.

Among these, polymers of α,β-ethylenically unsaturated monomers are particularly preferred from the viewpoint of performance.

The polymer of α,β-ethylenically unsaturated monomer that is most preferably used as the synthetic resin (A) used in the present invention is, for example, a polymer selected from the group consisting of hydroxyl group, alkylol group, and glycidyl group. (α, β both have one type of functional group)
- Ethylenically unsaturated monomer (a1), α, β ethylenically unsaturated monomer (a2) having a carboxyl group, and other α, β-monoethylenically unsaturated monomers 5 as necessary , and the synthetic resin (A).

These monomers (a1), (ax) and (a3)
The copolymerization ratio of monomer 5 and synthetic resin (A) is not particularly limited and varies depending on the intended use and required performance.

(a2) and 5, when the total of synthetic resin (A) is 100 parts by weight, usually monomer (a1) 0.5 to 50 parts by weight, monomer (ax) 0.1 to 30 parts by weight, Monomer (as
) 20-99.4 parts.

The reaction conditions for obtaining the above polymer are not particularly limited, but usually in the presence of a radical polymerization initiator
Polymerization may be carried out at 5°C, preferably 50 to 80°C, for 30 minutes to 24 hours. Of course, the above reaction can be carried out without a solvent, in an organic solvent,
It can be done either underwater. However, emulsion polymerization is preferred because the reaction is simple and the polymer can be obtained in a dissolved or dispersed form in an aqueous medium with very little fire or pollution.

Monomer 5, an α,β-ethylenically unsaturated monomer having a hydroxyl group among the synthetic resins (A) that can be used in producing the above polymer, includes, for example, (meth)acrylic acid-
2-hydroxylethyl, (meth)acrylic acid-2-
Hydroxypropyl, trimethylolpropane mono (
meth)acrylate, trimethylolpropane di(meth)acrylate, allyl alcohol, glycerin monoallyl ether, ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, and other monomers that create hydroxyl groups by hydrolysis, such as vinyltriethoxy Examples include silane, T-methacryloxypropyltrimethoxysilane, and the like.

Examples of the α,β-ethylenically unsaturated monomer having an alkylol group include N-alkylol (meth)acrylamide such as N-methylol (meth)acrylamide;
~ N-alkyl etherified (meth)acrylamides such as butoxymethyl (meth)acrylamide, etc. are mentioned.

Examples of the α,β-ethylenically unsaturated monomer having a glycidyl group include glycidyl esters and allyl glycidyl ethers of monoethylenically unsaturated carboxylic acids such as methylglycidyl (meth)acrylate and glycidyl (meth)acrylate. and methyl allyl glycidyl ether, allyl alcohol glycidyl ether which may have an alkyl substituent, and the like.

Examples of the α,β-ethylenically unsaturated monomer (a) having a carboxyl group include monoethylenically unsaturated carboxylic acids such as (meth)acrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid. ; Monomethyl maleate,
Examples include monoethylenically unsaturated dicarboxylic acid monoalkyl esters such as monoethyl fumarate and mono-n-butyl icotanate. Further, other α,β-ethylenically unsaturated monomers (a3) include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, Pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate,
(meth)acrylic esters such as octadecyl (meth)acrylate; monoethylenically unsaturated aromatic monomers such as styrene, α-methylstyrene, vinyltoluene, chlorostyrene, and 214-dibromustyrene; (meth)acrylonitrile unsaturated nitriles such as; vinyl esters such as vinyl acetate, vinyl propionate, vinyl versatate; vinylidene halides such as vinylidene chloride and vinylidene bromide; alkenes such as ethylene, propylene, butylene;
butadiene-1,3,2-methylbutadiene-1,3,
2-Chlorbutadiene-1,3, pentadiene-1,3
Conjugated dienes such as

Examples of the radical polymerization initiator include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, aqueous catalysts such as 2,2'-azobis-(2-amidinopropane) dihydrochloride, benzoyl peroxide, t -Oil-based catalysts such as butyl hydroperoxide and cumene hydroperoxide can be mentioned. The amount of radical polymerization initiator used is usually 100% by total weight of monomers.
The amount is 0.1 to 5 parts by weight. In producing the above polymer, emulsifiers such as polyoxyethylene nonylphenyl ether, chain transfer agents such as lauryl mercaptan and dodecyl mercaptan, ethylenediaminetetraacetic acid for the purpose of stabilizing polymerization, or sodium hydroxide for pH adjustment are used. There is no problem in using various additives such as bases such as dimethylethanolamine and triethylamine as necessary.

The polymer thus obtained may be subjected to concentration and removal of unreacted S-mer and organic solvent, if necessary.

By adding a basic compound to the synthetic resin (A) used in the present invention, a synthetic resin that is stably dissolved or dispersed in an aqueous medium can be obtained.

Basic compounds include inorganic basic compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, and barium carbonate, and organic basic compounds such as ammonia, dimethylamine, trimethylamine, triethylamine, jetanolamine, monoethylamine, and diethylamine. Can be mentioned.

Among them, volatile organic amines can seal carboxyl groups that serve as crosslinking points, and in actual use, they volatilize to release active carboxyl groups and react with carbodiimide bonds, and moreover, they are highly volatile in the cured product after the reaction. It is preferable because it does not easily remain in water and has excellent storage stability.

The amount of the basic compound added is usually such that the pH of the polymer is 5 to 8.

The carbodiimide compound (B) used in the present invention refers to a compound having at least one carbodiimide bond, that is, -N=C=N- bond, in the molecule, and in particular, a carbodiimide compound having 1 to 4 carbodiimide bonds in the molecule. is preferred.

The carbodiimide compound (B) can be obtained, for example, by removing carbon dioxide from an isocyanate compound. In the carbon dioxide removal reaction, a catalyst or an organic solvent may be used as necessary.

Usually, to obtain the carbodiimide compound (B), carbon dioxide is removed from the isocyanate compound in an organic solvent in the presence of a catalyst at 100 to 200°C, preferably at 130°C because it produces fewer by-products and can shorten the reaction time. The reaction may be carried out at ~160°C until the amount of carbodiimide bonds produced becomes constant.

The incyanate compound may be a monoisocyanate alone, a polyisocyanate alone, or a mixture thereof, but a combination of monoisocyanate and diisocyanate in a molar ratio of about 2=2 to about 2:4 is preferred. . Examples of the isocyanate compound include monoisocyanates such as methyl isocyanate, ethyl isocyanate, propyl isocyanate, butyl isocyanate, octadecyl isocyanate, and phenyl isocyanate, hexamethylene diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and cyclohexane diisocyanate. , diisocyanates such as dicyclohexylmethane diisocyanate, xylene diisocyanate, meta-xylene diisocyanate, trimethylolpropane triisocyanate, triphenylmethane triisocyanate, hexamethylene diisocyanate cyclic trimer, and the like. Examples of organic solvents include ethyl butyl ketone, methyl isobutyl ketone, acetophenone, propiophenone, diisobutyl ketone, cyclohexanone,
Decalin, methyl cellosolve acetate, cellosolve acetate, butyl cellosolve acetate, carpitol acetate, butyl carpitol acetate, amyl acetate, butyl acetate, propyl propionate, ethyl butylade, xylene, toluene, diethylbenzene, benzene, Examples include diethylene glycol ether diacetate, dipropylene glycol ether dibutyrate, hexylene glycol diacetate, and the like.

Examples of the catalyst include phosphine, phosphorine, phospholidine, trialkyl phosphate, phosphorene sulfide, and phospholene oxide.

The carbodiimide compound (B) obtained as described above can be made into an aqueous solution or an aqueous dispersion of the carbodiimide compound (B) by adding water and, if necessary, a surfactant and stirring and mixing. As the surfactant, any known and commonly used surfactant can be used, but anionic surfactants such as alkali metal salts of dialkyl sulfosuccinic acid are particularly preferred.

Furthermore, by adding a basic compound to the carbodiimide compound (B), hydrolysis of the carbodiimide bond in the carbodiimide compound can be prevented.

Examples of basic compounds include inorganic basic compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, and barium carbonate, and organic basic compounds such as ammonia, dimethylamine, trimethylamine, triethylamine, diethylamine, monoethylamine, and diethylamine. . Among them, volatile organic amines are particularly preferred because they are less likely to remain in the cured product obtained after the reaction of carboxyl groups, other specific functional groups, and carbodiimide bonds, and because the carbodiimide compound has excellent storage stability.

The amount of the basic compound added is usually the same as that of the carbodiimide compound (
This is the amount such that ρ11 in B) is 5 to 8. Synthetic resin (A)
The mixing ratio of carbodiimide compound (B) and carbodiimide compound (B) is not particularly limited, but usually 0.1 to 50 parts by weight, especially 0.5 to 30 parts by weight of carbodiimide compound (B) per 100 parts by weight of solid content of synthetic resin (A). part is preferred.

The synthetic resin composition of the present invention includes synthetic resins other than the synthetic resin (A), such as acrylic resins containing in the molecule at least one anionic group selected from the group consisting of a carboxyl group, a sulfonic acid group, and a phosphoric acid group. resin, polyester resin,
Urethane resin, polyamide resin, polyurea resin, and polyurethane polyurea resin may be added and used. Further, if necessary, pigments, dyes, fillers, thickeners, waxes, tackifier-1 plasticizers, etc. may be added and used. These may be added to the synthetic resin (A) in advance, or
It may be added to the carbodiimide compound (B).

The synthetic resin composition of the present invention can be cured to exhibit sufficient water resistance at low temperatures, especially at room temperature, when applied as paints, adhesives, and various resin processing agents (wood, fibers, paper, cement, leather, etc.). Can form things.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples. Unless otherwise specified, parts and percentages are by weight.

Reference Example 1 [Synthesis of synthetic resin (A)] A condenser, a thermometer, and a dropping funnel were attached to a reaction vessel equipped with a stirrer, and 0.3 parts of sodium lauryl sulfate and 3.0 parts of polyoxyethylene nonylphenol ether were placed in the vessel purged with nitrogen. and 89.0 parts of deionized water were added.

Next, the temperature inside the container was raised to 80°C, and while stirring, a monomer mixture consisting of 55 parts of butyl acrylate, 42 parts of methyl methacrylate, 2 parts of methacrylic acid, and 1 part of β-hydroxymethacrylate was added. Aqueous catalyst solution prepared by dissolving 0.3 parts of ammonium persulfate in deionized water was added to each
The mixture was added dropwise over 80 minutes to polymerize. During this time, the temperature inside the container was adjusted to 2° C. for 80 parts. Thereafter, it was cooled, and the pH was adjusted to 18 using aqueous ammonia, and the solid content concentration was adjusted to 50%. This was designated as dispersion liquid A-1.

Comparative Reference Example 1 Copolymerization was carried out in the same manner as in Reference Example 1 except that the monomer composition was changed to 55 parts of butyl acrylate, 43 parts of methyl methacrylate, and 2 parts of methacrylic acid, and the pH was adjusted using ammonia water.
8 and the solid content concentration was adjusted to 50%. This was designated as dispersion liquid a-1.

Reference Examples 2 to 4 [Production of synthetic resin (A)] Copolymerization was carried out in exactly the same manner as in Reference Example 1, except that the monomer composition was changed as shown in Table 1. Type concentration 50%
Adjusted to. These dispersions are A-2 and A-3, respectively.
, A-4.

Table 1 Comparative Reference Example 2 Copolymerization was carried out in exactly the same manner as in Reference Example 1, except that the monomer composition was changed to 80 parts of butyl acrylate, 18 parts of methyl methacrylate, and 2 parts of acrylic acid. pl(8,
The solid content concentration was adjusted to 50%.

This was designated as dispersion a-'l.

Reference Example 5 [Synthesis of Compound (B)] A stirrer and a thermometer were attached to a reaction vessel equipped with a stirrer, and after purging with nitrogen, the following substances were added into the vessel.

Butyl isocyanate 22.7 parts Isophorone diisocyanate 127.3 parts 3-Methyl-1-phenyl-2-phosphosine-1-oxide
0.2 parts Butylcarpitol acetate 132.0 parts Then, the temperature inside the container was lowered to 1
The temperature was raised to 45°C and kept at the same temperature for 10 hours. After cooling, the infrared spectrum of the reactant was measured, and it was found that 22
The peak of 60cr' (characteristic absorption band of isocyanate group) disappeared, and 2130ca+-' (characteristic absorption band of carbodiimide bond) was formed.

Zaremko and Wat method (Micro Ches, J
, 5ys-P, Ser., 2.591 (1962)
It is described in. ] The number of carbodiimide bonds in the reactant was 4. The active ingredient of this polycarbodiimide solution was 53.2%.

While stirring the above polycarbodiimide compound organic cutting solution,
The following substances were added in order to obtain a polycarbodiimide emulsion.

The above polycarbodiimide compound (active ingredient) 20 parts Triethylamine 2 parts Sodium dialkylsulfosuccinate 1 part Deionized water 59 parts This emulsion was designated as Dispersion B.

Examples 1 to 5 and Comparative Examples 1 to 2 Dispersions A-1 to A-4 and a obtained in Reference Examples and Comparative Reference Examples
-1 and Dispersion B were mixed in the proportions shown in Table 2 to obtain a clear paint. Apply these paints to polished steel plates (JIS, G-3
141 standard bright finish) using a 3 mil applicator and dried at room temperature for 10 days to obtain a coated plate.
The water resistance, alkali resistance, and solvent resistance of the painted plates were visually observed.

Water resistance: The above coated plate was immersed in water at 35°C for 7 days, and changes in the state of the film were observed.

Alkali resistance: The above coated plate was immersed in a 2% Na leaf solution at 25°C, and changes in the state of the film were observed.

Solvent resistance: The above coated plates were immersed in toluene and methyl ethyl ketone for 24 hours each, and changes in state were observed.

The criteria for each evaluation were as follows.

○: Good (no change in surface condition) △: Slightly poor (slight occurrence of blisters, lifting, reduction in gloss, etc.) ×: Poor (large amount of blisters or dissolution of the coating film, etc.) / F/ As can be seen from Table 2, it can be seen that the paint using the synthetic resin composition of the present invention provides a coating film that is not only resistant to alkali and solvents, but also has excellent water resistance. .

Dispersions A-2 to A-4 and a obtained in Example Reference Side Comparative Reference Example
-2 and Dispersion B were mixed in the proportions shown in Table 3 to obtain an adhesive. This adhesive was applied to a 30 μm thick polypropylene film (pretreated by corona discharge) to a dry weight of 5 g/m, and after drying at room temperature for 10 days, the same polypropylene film as above was rolled onto a rubber roll. The resulting laminate was heat-treated at 60°C for 3 minutes, then left at room temperature for 3 days, 40°C,
The adhesive strength was measured after being left at 95% RH for 3 days. In addition, as a measure of water resistance, the adhesive strength at room temperature using a laminate that has been left at room temperature for 3 days is called normal strength, 4
Table 3 shows the adhesive strength at room temperature using a laminate that was left at 0° C. and 95% RH for 3 days as the strength after heating.

As a measure of heat resistance, adhesive strength at 50°C is shown in Table 3 as hot strength.

In addition, the size of the test piece is 150 mm x 15 m + Il,
The adhesive strength was measured using an Autograph (manufactured by Shimadzu Corporation) at a peeling speed of 30011IIIZ and a T-type size M (a peeling method in which two polypropylene films bonded together with an adhesive are pulled from above and below).

It can be seen from Table 1 that adhesives using the synthetic resin composition of the present invention have not only water resistance but also heat resistance and have excellent adhesive strength.

(Effect of the invention) Since the synthetic resin composition of the present invention uses a synthetic resin having not only a carboxyl group but also a specific crosslinkable functional group, when using a conventional synthetic resin having only a carboxyl group, It can provide a cured product with excellent water resistance compared to other methods. Moreover, the synthetic resin composition of the present invention, which is dispersed in an aqueous medium, can exhibit the particularly remarkable effect of significantly reducing the occurrence of fire and pollution.

Therefore, the synthetic resin composition of the present invention can be used for many purposes. For example, coating textiles, paper, leather, wood, metals such as metal coils, impregnating fibers and textiles, binders for blankets, adhesives such as pressure sensitive adhesives, backing agents, hydrophobizing agents. , as an elasticizing component or a crushing prevention component in the construction industry (for example, as an additive to concrete mixtures and asphalt mixtures), as a vehicle for various paints such as plastic undercoats, paints, and hardboard paints, and for external paints. It can be used for household aerosol paints, etc. It can also be used as a binder for coal powder, wood powder, glass fiber, asbestos, paper, plastic, rubber scrap, ceramic materials, etc.

Furthermore, the synthetic resin composition of the present invention can be used as a softening agent in the production of elastic films, foils, and yarns, as an auxiliary agent in textile printing and yarn industries, as an additive for synthetic resin dispersions, and as a sizing agent. It can be used in a wide range of applications, including as a leather finishing agent.

Claims (1)

[Claims] 1. A synthetic resin having a carboxyl group and a functional group other than the carboxyl group that can react with a carbodiimide bond (A
) and a carbodiimide compound (B). 2. The composition according to claim 1, wherein the functional group other than the carboxyl group that can react with the carbodiimide bond is at least one functional group selected from the group consisting of a hydroxyl group, an alkylol group, and a glycidyl group. 3. The composition according to claim 1, wherein the synthetic resin (A) and the compound (B) are dissolved or dispersed in an aqueous medium. 4. α,β-ethylenically unsaturated monomer (a_1) in which the synthetic resin (A) has at least one functional group selected from the group consisting of a hydroxyl group, an alkylol group, and a glycidyl group
A copolymer consisting of an α,β-ethylenically unsaturated monomer (a_2) having a carboxyl group, and another α,β-ethylenically unsaturated monomer (a_3) that can be copolymerized with them. 2. The composition according to claim 1, wherein compound (B) is a carbodiimide compound having 1 to 4 carbodiimide bonds. 5. Synthetic resin (A) contains 0.5 to 50 parts by weight of monomer (a_1), when the total of monomers (a_1), (a_2) and (a_3) is 100 parts by weight. (a_2)
0.1 to 30 parts by weight and the monomer (a_3) 20 to 9
5. The composition of claim 4, which is a copolymer comprising 9.4 parts by weight. 6. The composition according to claim 5, wherein 0.1 to 50 parts by weight (solid content ratio) of the compound (B) is mixed with 100 parts by weight of the synthetic resin (A). 7. The composition according to claim 3, 4, 5 or 6, wherein the synthetic resin (A) and the compound (B) are dissolved or dispersed in an aqueous medium.