JPH03247663A - Curable resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition exhibiting excellent workability and reactivity without being influenced by humidity, water etc., and capable of providing a coating having good chemical resistance, weather resistance and general-purpose properties by blending a grafted primary amino group-containing polymer with a dialkyl oxalate. CONSTITUTION:(A) A grafted primary amino group-containing polymer modified by animating a side-chain carboxyl group-containing polymer with a compound expressed by the formula H2N-R1-NH2 (R1 is CnRaH2n-a, etc.; n is 2-6; a is 0-2; R is H, CH3 or C2H5) or the formula [H2N-(R2)x]y-Z (R2 is CnRaH2n-aO; n is 2-4; a is 0-2; R is H, CH3 or C2H5; x is 1-60; y is 2-10; z is alkyl, etc.) is blended with a dialkyl oxalate expressed by formula I (R3 is 1-8C lower alkyl).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides (a) a polymer containing a side chain carboxyl group, a polyamine having an aliphatic amino group, or a polyamine having an aliphatic amino group and at least one ether. A curable resin characterized in that it contains as essential components a polymer containing a grafted primary amino group obtained by reacting a polyamine containing a polyamine group, and (b) a dialkyl oxalate having an active ester group that undergoes an exchange reaction with an amino group. The present invention relates to a composition.

[Prior Art] Conventionally, curable resin compositions include curable resin compositions of polyhydric alcohol compounds such as polyester polyols and acrylic polyols and polyvalent isocyanate compounds, and polyvalent amines such as polyamines and polyamide amines. Curable resin compositions of compounds and epoxy resins are used in a wide variety of applications, including paints, adhesives, surface treatment agents, molded products, and foamed resins.

In addition, Michael addition curable resin compositions of polyvalent amine compounds such as polyamines and polyamidoamines and polyvalent acryloyl groups, which are recently described in JP-A No. 61-23615, etc., and U.S. Pat. No. 4,415,250, etc. A curable resin composition of a polyvalent amine compound and dialkyl oxalate described in .

[Problems to be Solved by the Invention] However, although the curable resin composition of a polyhydric alcohol compound and a polyhydric incyanate compound has characteristics such as reactivity, weather resistance, and versatility, the incyanate The problem is the toxicity of the compound, the problem that it basically cannot be used in an aqueous system because it reacts with water, and the problem of suppressing side reactions of the incyanate compound due to water, moisture, etc. even when used in a cutting system or a solvent-free system. There are management problems, and these problems have not yet been solved.The characteristics of curable resin compositions of polyvalent amine compounds and epoxy resins, such as their reactivity, chemical resistance, and versatility, are Some have problems with weather resistance, low temperature curing, etc.

Michael additive curable resin compositions of polyvalent amine compounds and polyvalent acryloyl groups have excellent performance in terms of low temperature curability, weather resistance, etc., but have problems in chemical resistance, gloss, etc. Curable resin compositions of polyvalent amine compounds such as polyamines and polyamidoamines and dialkyl oxalates have problems such as slow rise in molecular weight and slow development of desired physical properties due to the reaction between oligomers and monomers. In order to improve this, we developed a curable resin composition of a polyamine compound obtained by modifying a copolymer of a copolymerizable acid anhydride such as maleic anhydride and other copolymerizable monomers with a polyamine and dialkyl oxalate. However, copolymers containing acid anhydride groups have problems such as slow development of desired physical properties because the polymerization rate does not increase, and internal salt formation with residual carboxyl groups. There was a problem that the curing reaction was delayed due to the formation of.

[Means for Solving the Problems] The present inventors have developed a curable resin composition of a polyhydric alcohol compound and a polyvalent incyanate compound, a curable resin composition of a polyvalent amine compound and an epoxy resin, and In order to develop a curable resin composition that does not have the above-mentioned problems found in the Michael addition curable resin composition of a polyvalent amine compound and a polyvalent acryloyl group, we developed a combination of a polyvalent amine compound and dialkyl oxalate. After paying attention to curable resin compositions and conducting extensive studies, we have arrived at the present invention.

That is, the present invention provides (a) a polymer containing a side chain carboxyl group with the general formula (I> H2N-R1-NH2... (I> (wherein R1 is Cn Ra H2n-a (here where n is 2 to 6, a is 0 to 2, R is H, CH3 or C2H5) (CnRa
H2n-aO)x ''' (where n is 2-6, a is 0-2, R is H, CH3 or C2H5, x is 1-60
, R' is an alkylene group having 2 to 6 carbon atoms)) or - Formula (n) [H2N-(R2)X]y-2... (■) (wherein R2 is Cn Ra H2n -aO (where n is 2~
4, a is 0-2, R is H, CH33 or C2H5, X
is 1 to 60, y is 2 to 10, Z is an alkyl, aryl or alkylaryl group), and (b) - Formula (1) 0 0 1111 Dialkyl oxalate represented by R-0-C-C-0-R3 (III) (wherein R3 is selected from the group consisting of lower alkyl groups having 1 to 8 carbon atoms) The present invention relates to a curable resin composition comprising as an essential component.

More specifically, the (a) polymer having a grafted primary amino group used in the present invention is described in, for example, JP-A-61-625.
Carboxyl group of a polymer obtained by copolymerizing an unsaturated monomer containing a carboxyl group described in No. 69, Japanese Patent Publication No. 62-17601, and other copolymerizable unsaturated monomers. used in the present invention is a polymer having a grafted primary amino group obtained by reacting a polyamine having an aliphatic amino group or a polyamine having an aliphatic amino group and at least one ether group ( b) Dialkyl oxalate has the general formula (I[[
> 0 11I R-0-C-C-0-R3 (III) (wherein R3 is selected from the group consisting of lower alkyl groups having 1 to 8 carbon atoms) Dimethyl oxalate, diethyl oxalate, diglopyl oxalate, di-1so-propyl oxalate, di-n-butyl oxalate, di-1so-butyl oxalate, di-2-ethylhexyl oxalate, etc. Listed 9
The curing mechanism of the present invention is expressed by the following general formula.

0 In order to express the characteristics of the physical properties of the cured product of the curable resin composition of the present invention, as is clear from the above-mentioned curing mechanism, it is necessary to Theoretical curing is an exchange reaction with one molecule of dialkyl acid and curing at an amide bond, and based on this, it can be used at the following molar ratio.

(Number of moles of general formula (III[))/(Number of moles of primary amino group) -0,1-2,0, more preferably 0.2
The molar ratio ranges from 1.0 to 1.0.

[Function] The present invention provides (a) a polymer containing a side chain carboxyl group with the general formula (I) HN-R1-NH2 (I> (wherein R1 is
CRH (where n is 2 to na 2n-a 6, a is 0 to 2, R is H, CH33 or C2Hs)
(CoRaH2n-aO)x-R' (where n is 2~
6, a is 0-2, R is H, CH33 or C2H5, x
is 1 to 60, R' is an alkylene group having 2 to 6 carbon atoms)) or - Formula (n) [HN (R2) x] y Z...''・(n
) (in the formula, R is CoR8H2n-aO, where n is 2 to
4, a is 0 to 2, R is H, CH3 or C2H5, X is 1 to 60, y is 2 to 10, Z is an aminated primary graft which has been modified by amination with an alkyl, aryl or alkylaryl group) An amino group-containing polymer and (b) - Formula (III) 0 111 R-0-C-C-0-R3 (III) (wherein R3 is lower alkyl having 1 to 8 carbon atoms) By providing a curable resin composition characterized by containing as an essential component a dialkyl oxalate represented by (selected from the group consisting of It is possible to provide a curable resin composition that has properties such as chemical resistance, weather resistance, and versatility. Furthermore, this curable resin composition can be used in a wide variety of applications such as paints, adhesives, surface treatment, molded products, and foamed resins.

[Examples] Hereinafter, embodiments of the present invention will be specifically illustrated and explained by way of Examples.The present invention is not limited to these Examples in any way.

In the examples, parts indicate parts by weight.

[Amino group-containing polymer] Reference example 1 119.6 parts of dipropylene glycol monomethyl ether and 15 parts of modified ethanol were placed in a 1J flask equipped with a stirrer, reflux condenser, thermometer, nitrogen inlet tube, and dropping funnel.
After charging 1 part, the mixture was heated to reflux at 130°C while nitrogen was introduced. 66.2 parts of ethyl acrylate and 16 parts of styrene
5 parts of acrylic acid, a mixture of 15.8 parts of 50% t-butyl peracetate solution and 7.8 parts of dipropylene glycol monomethyl ether were added dropwise over 2 and a half hours. After the completion of the dropwise addition, aging was carried out for 1 hour, and the volatile matter was distilled off by further heating to 180°C.Next, 22.3 parts of dipropylene glycol methyl ether and Chefamine D-400 (trade name: Jefferson Chemical Co., Ltd.) were added. diamine, NH2[CH(CH
3) CHO] CHCH(CH')NH2)42
5.6 2 359.7 parts were added, heated under reflux again, and reacted for 1.5 hours. After the reaction was completed, it was cooled, and 11.5 parts of deionized water and 55.4 parts of ethylene glycol monoethyl ether were added to reduce the non-volatile content to 73. %
A grafted amine-containing acrylic copolymer was obtained.

Reference Example 2 300 parts of propylene glycol monomethyl ether was placed in a flask similar to Reference Example 1, and 8 parts of propylene glycol monomethyl ether was charged while introducing nitrogen.
Do not raise the temperature to 0℃. 4 parts of a polymerizable monomer mixture consisting of 86.2 parts of methacrylic acid, 57.2 parts of methyl methacrylate, 158 parts of butyl acrylate, and 138.6 parts of styrene.
4 parts of azobisisobutyronitrile were added uniformly over time 15 minutes after the start of addition of the polymerizable monomer mixture to start polymerization 0 30 minutes after the start of polymerization 5. 6 parts of propylene glycol monomethyl ether was added uniformly until the dropwise addition of the polymerizable monomer mixture was completed, and the polymerization was completed by further aging at 80 to 85°C for 6 hours.9 Next,
Add 2.62 parts of 305 parts of propylene glycol monomethyl ether and 225 parts of Shefamine D-230 (trade name: diamine manufactured by Jefferson Chemical Company, NH[CH(CH)CH20]3 CHCH(CH3)NH2) and heat to reflux. A grafted amine-containing acrylic copolymer having a nonvolatile content of 50% was obtained by reacting for a period of time.

Reference Example 3 Add isopropyl alcohol 3 to the same flask as Reference Example 1.
After charging 36 parts of methacrylic acid and 224 parts of toluene, the temperature was raised to 80°C while introducing nitrogen, and a mixture was prepared from 72 parts of methacrylic acid, 120 parts of butyl acrylate, 48 parts of styrene, and 9.6 parts of azobisisobutyronitrile. A polymerizable monomer mixture was added dropwise over 2 hours. After the addition was completed, the polymerization was completed by further aging at 80°C for 6 hours. Next, Reference Example 2
188 parts of Shefamine D-230 used in the above was added, heated under reflux, and reacted for 4 hours to obtain a grafted amine-containing acrylic copolymer with a nonvolatile content of 43.3%.

Example 1 12.7 parts of diethyl oxalate was added to 100 parts of the amino group-containing polymer obtained in Reference Example 1 and mixed uniformly. The following tests were conducted using this mixture. The results are shown in Table-1.

[Coating film curing test and evaluation criteria] (1) Drying property: The above mixture was applied onto a glass plate using a 75 μm applicator, and dried to the touch and cured using an RCC todrying meter at 25°C and 60% relative humidity. Evaluation was made based on drying time.

(2) Pencil hardness; After coating in the same manner as in (1) and curing for 7 days, the scratch hardness of the pencil at a load of 250 gr was measured using a pencil scratch tester according to JIS K-5400.

(3) Gel fraction: An appropriate amount of the above mixture was applied on a Teflon plate, and after 7 days of aging, the coating was peeled off, and the gel fraction was measured by extracting with acetone for 4 hours using a Soxhlet extractor.

Further, 29 parts of titanium oxide was added to 100 parts of the above base resin and thoroughly mixed, and 12.7 parts of diethyl oxalate was further added and mixed uniformly to obtain a coating composition.

The following tests were conducted using this formulation.

The results are shown in Table-1.

[Paint film performance test and evaluation criteria code] (4) Weather resistance :Place the above compound on a stainless steel plate. with a 75μm applicator Coated, 25℃, relative humidity 60 % after curing for 7 days JIS K- Sunshine according to 5400 240 hours on type weather meter Observe the condition of the paint film after irradiation. I guessed it.

[Colorfastness] ◎；No change ○: Slight discoloration △; Slight discoloration ×: Discoloration [Gloss retention rate] Gloss retention rate from initial gloss Display in .

(5) Solvent resistance: The coating film applied in the same manner as in (4) was lapped using methyl ethyl ketone, and the number of times of rubbing until the coating film deteriorated was measured.

Examples 2 to 3 Mixtures and paint formulations shown in Table 1 were prepared using the copolymers obtained in Reference Examples 2 and 3, and the same tests as in Example 1 were conducted.

Comparative Example 1 The same procedure as in Example 1 was carried out, except that 28.7 parts of the diethyl oxalate of Example 3 was added to Epicote 828 (trade name: epoxy compound manufactured by Yuka Shell Co., Ltd., bisphenol A type diglycidyl ether). Mixtures and paint formulations were prepared and tested. The results are shown in Table-1.

Comparative Example 2 Using commercially available polyamide amine as a main ingredient, 122 parts of Epikote 828 was added to 100 parts of the main ingredient and mixed uniformly. The test was conducted in the same manner as in Example 1 except that this mixture was used. The results are shown in Table-1.

Further, a coating composition was obtained in the same manner as in Example 1 by adding 18 parts of titanium oxide and appropriate amounts of glass beads to 100 parts of the above base resin. The test was conducted in the same manner as in Example 1 except that this formulation was used. The results are shown in Table-1.

Comparative Example 3 Commercially available acrylic polyol (hydroxyl value 80 rw K O
) (/gr, 5olid, non-volatile content 50%, toluene,
Using 100 parts of n-butyl acetate solution as a main ingredient,
18 parts of hexamethylene diisocyanate trimer (NCO content 16.5%, nonvolatile content 75%, ethyl acetate solution) was added, mixed uniformly, and diluted with toluene. The test was conducted in the same manner as in Example 1 except that this mixture was used.

The results are shown in Table-1.

Further, 30 parts of titanium oxide and appropriate amounts of glass beads were added to 100 parts of the above acrylic polyol with a non-volatile content of 40% in toluene, and mixed in the same manner as in Example 1. This was added to a trimer of 1,6-hexamethylene diisocyanate (NGO content 1665%, non-volatile content 75%,
966 parts of ethyl acetate solution were added and mixed uniformly to obtain a paint formulation. The test was conducted in the same manner as in Example 1 except that this formulation was used. The results are shown in Table-1.

[Effects of the Invention] As is clear from the examples, the curable resin composition of the present invention is not affected by humidity, water, etc., has excellent workability and reactivity, and has excellent chemical resistance and weather resistance. It has characteristics such as flexibility and versatility, and can be used in a wide variety of applications such as paints, adhesives, surface treatment agents, molded products, and foamed resins that take advantage of these characteristics.

Claims (1)

[Claims] (1) (a) A polymer containing a side chain carboxyl group has the general formula (I) H_2N-R_1-NH_2...(I) (in the formula, R1 is C_nR_aH_2_n_-_a (here n
is 2-6, a is 0-2, R is H, CH3 or C_2H
_5), (C_nR_aH_2_n_-_aO)_x-
R' (where n is 2 to 6, a is 0 to 2, R is H, CH_
3 or C_2H_5, x is 1 to 60, R' is an alkylene group having 2 to 6 carbon atoms)) or general formula (II) [H_2N-(R_2)x]y-Z... (II)
(In the formula, R_2 is C_nR_aH_2_n_-_aO(
where n is 2 to 4, a is 0 to 2, R is H, CH_3 or C_2H_5, X is 1 to 60, y is 2 to 10, Z is aminated and modified by (b) General formula (III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(III
) (wherein R_3 is selected from the group consisting of lower alkyl groups having 1 to 8 carbon atoms.) A curable resin composition comprising as an essential component a dialkyl oxalate represented by the formula: