JPH01153703A - Curable resin - Google Patents

Abstract

PURPOSE:To obtain a novel resin having excellent physical properties by crosslinking and esterification, with a dihydric alcohol, of part of the carboxyl group, i.e. one of the side chains in a resin with alpha,beta-unsaturated carboxylic anhydride-vinyl compound copolymer as the basic skeleton. CONSTITUTION:The objective resin can be obtained by crosslinking and esterification, with a dihydric alcohol, of part of the carboxyl group in a resin with alpha,beta-unsaturated carboxylic anhydride-vinyl compound copolymer as the basic skeleton and the side chains in the alpha,beta-unsaturated carboxylic acid skeleton being a mixture of carboxyl group, unsaturated alcohol ester group (pref. allyl alcohol or hydroxyethyl acrylate so the unsaturated alcohol) and saturated alcohol ester group (pref. propyl alcohol or octyl alcohol as the saturated alcohol). Said alpha,beta-unsaturated carboxylic acid anhydride is pref. maleic anhydride, while said vinyl compound is pref. styrene or acrylonitrile.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a novel curable resin.

More specifically, the present invention has an α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer as a basic skeleton,
- It relates to a novel curable resin in which a part of the carboxyl group, which is one of the side chains in the unsaturated carboxylic acid skeleton, is cross-linked and esterified with a dihydric alcohol.

[Prior art] 0]! The type of curable resin that has a carbon-carbon double bond in Is has superior physical properties compared to curable resins such as unsaturated polyester resins that have a carbon-carbon double bond and an ester bond in the main chain. Due to its high performance, its applications are expanding in various fields.

The above compound is produced by reacting a compound having a carbon-carbon double bond in its side chain with the main chain of another compound having no carbon-carbon double bond in its side chain.

For example, the acid anhydride group of a copolymer of an α,β-unsaturated acid anhydride and a vinyl compound may be substituted with an acid anhydride group such as allyl alcohol, 2-hydroxyethyl methacrylate, or 2-2-hydroxyethyl acrylate. A carbon-carbon double bond is created in the side chain by reacting the esterified compound and its free carboxyl group with an unsaturated epoxy compound such as allyl glycidyl ether, glycidyl methacrylate, or glycidyl acrylate with a saturated alcohol. It is possible to produce a resin having

An example of such a compound is one having the following structure.

(However, R is an alkyl group, a compound residue that does not have an active double bond such as a benzene nucleus, R- is an allyl group, etc.2
[Problems to be solved by the invention] However, when the acid anhydride group of the α,β unsaturated carboxylic acid anhydride-vinyl compound copolymer is replaced with allyl alcohol, 2-hydroxyethyl methacrylate , 2-hydroxyecal acrylate, which are simply esterified with unsaturated alcohols, have free carboxyl groups remaining and therefore have a high acid value.

When most of the carboxyl groups are blocked by esterification using a compound having a double bond such as allyl alcohol (i.e., when the number of R- in the above formula increases relative to the carboxyl group), the acid value increases. Although it is possible to reduce the curability, the curability becomes excessive.

On the other hand, if most of the carboxyl groups are blocked by esterification using a compound having no double bonds, the acid value can be lowered, but curability is not imparted.

That is, the balance between acid value and curability cannot be controlled by the above-mentioned means.

If used with a high acid value, it will be difficult to dissolve in solvents such as propylene glycol acetate, and if used in the process of reacting free carboxyl groups with unsaturated epoxy compounds such as glycidyl (meth)acrylate, the epoxy compound and The reaction rate increases and gelation of the resin occurs,
An unmoldable mass forms.

Conversely, if the amount of double bonds is insufficient, curability will be insufficient.

Furthermore, if the reaction rate of the unsaturated epoxy compound is suppressed in order to prevent gelation of the resin, the reaction rate of free carboxyl groups will not increase sufficiently, making it impossible to obtain a resin with good performance.

On the other hand, as mentioned above, all unbalanced resins have inherent stickiness, which causes various problems such as being sticky and reducing work efficiency, and being too hard and difficult to mold. ing.

In either case, the applications will be limited.

Therefore, the present inventors have discovered a new resin having a structure in which the acid value and the amount of double bonds can be freely changed, and have previously disclosed it in the specification attached to the application filed on December 7, 1988.

The basic skeleton is an α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer, and the side chains in the α,β-unsaturated carboxylic acid skeleton are (a) carboxyl groups (b) unsaturated alcohol ester groups (c) A resin is disclosed that is a mixture of saturated alcohol ester groups.

However, even the above resins are still not sufficient in terms of freely controlling the balance of various properties, especially the viscosity and hardness of the resin.

As a result of intensive study, the present inventors have completed the present invention.

[Structure of the Invention] In other words, the present invention is based on "a basic skeleton of an α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer, and a side chain in the α,β-unsaturated carboxylic acid skeleton is (a) a carboxyl group. (b) an unsaturated alcohol ester group (c) a curable resin in which a portion of the carboxyl groups of the resin is cross-linked and esterified with a dihydric alcohol.

The present invention will be explained in detail below.

How to produce the curable resin of the present invention will be described later.
Perform the following four reactions.

In order to produce the α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer which is the starting material for the crosslinked esterified curable resin of the present invention, the following reaction is first carried out.

■Reaction between α,β-unsaturated carboxylic acid anhydride (e.g. maleic anhydride) and vinyl compound (e.g. styrene) -8= (However, R1 is an active double viscous group such as an alkyl group or a benzene nucleus. Examples of the α,β-unsaturated carboxylic acid anhydride used include maleic anhydride, citraconic anhydride, 2-ethylmaleic anhydride,
Examples include 2-phenylmaleic anhydride and 2-chloromaleic anhydride.

Furthermore, as the vinyl compound to be copolymerized with the α,β-unsaturated carboxylic acid anhydride, any vinyl compound that can be copolymerized with the α,β-unsaturated carboxylic acid anhydride can be used.
More than one species may be used in combination.

Typical examples of such vinyl compounds include styrene, 2-methylstyrene, acrylic esters, methacrylic esters, i! i1': Examples include acid vinyl, acrylonitrile, vinyl chloride, etc. Among these, styrene is particularly preferred.

The above-mentioned copolymer of α,β-unsaturated carboxylic acid anhydride and vinyl compound can be produced by a conventionally known method. In addition, in order to easily suppress the reaction, it is preferable to add the vinyl compound to the α,β-unsaturated carboxylic acid anhydride and cause the reaction. A method such as that disclosed in Japanese Patent Publication No.

That is, an α,β-unsaturated carboxylic acid anhydride such as maleic anhydride is dissolved in advance in a solvent containing a polymerization initiator, and a vinyl compound such as styrene and dialkylaniline as a chain transfer agent are added to this. The polymerization is carried out by dropping the polymerization initiator at a predetermined ratio, or by dissolving a polymerization initiator in a solvent and adding a mixed solution of a chain transfer agent and monomer mixed in advance. The temperature is 30-100℃, and the reaction time is usually 1
It takes about 0 hours.

The molecular weight of the polymer depends on the type of solvent, the amount of chain dynamic agent added, the ratio of monomer components, the polymerization temperature, etc.

Next, in order to react with the carboxylic acid anhydride group of the α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer obtained as described above to block a part of the carboxyl group, the following reaction was performed. conduct.

■α, β-unsaturated carboxylic acid anhydride-vinyl compound copolymer and saturated or unsaturated alcohol ■α, β-unsaturated carboxylic acid anhydride-vinyl compound copolymer partially esterified product and unsaturated or saturated alcohol (However, R2 and R3 are each a compound residue having a double bond such as an allyl group or a compound residue not having a double bond such as an alkyl group, x + y + z = n) of a carboxyl group. Examples of the saturated or unsaturated alcohol used for partially blocking the alkyl group include propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, 2-
3-dichloro-1-propanol, 2,3-dibromo-
Examples include 1-10 panol, allyl alcohol, 2-droxyethyl methacrylate, 2-droxyethyl acrylate, and benzyl alcohol.

A copolymer having a carboxylic acid anhydride group and a saturated or
The reaction with the unsaturated alcohol is carried out by adding a saturated or unsaturated alcohol having 3 or more carbon atoms and, if necessary, a catalyst to a solution of the copolymer in a solvent and heating and stirring the mixture.

The solvent is not particularly limited as long as it dissolves the copolymer, and examples thereof include aromatic hydrocarbons such as benzene, toluene, and xylene, ketones such as methyl ethyl getone, propylene glycol monoalkyl ether acetate,
Dipropylene glycol monoalkyl ether acetate and the like are used.

Among them, propylene glycol monoalkyl ether acetate is preferred.

This is because of its low toxicity, low price, and inertness to products.

The reaction with saturated or unsaturated alcohol may be carried out by mixing the two or may be carried out separately.

The usage ratio of saturated alcohol/unsaturated alcohol and the usage ratio of ampholyte/α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer depend on the amount of double viscosity to be imparted and the acid value to be set, i.e. It is set depending on how many carboxyl groups are not left.

Usually 0°1 to 1 per mole of acid anhydride group in the copolymer.
Within the molar range.

The concentration of the copolymer in the solution is appropriately selected so that the resin concentration in the final reaction solution is 10 to 90% by weight, but 40 to 90% by weight.
-60% by weight is particularly preferred.

If the concentration of the copolymer in the solvent exceeds 90%, the viscosity of the solution is high, making it difficult for a uniform reaction to proceed; conversely, if the concentration of the copolymer is less than 10%, a uniform reaction will not proceed. However, it is disadvantageous in terms of productivity such as solvent recovery and equipment scale.

In this esterification reaction, a conventionally known esterification catalyst is used as necessary, but a catalyst is not necessarily required for threads containing an excessive amount of alcohol.

When a catalyst is used, the amount used is 0.0% relative to the starting material.
0.001 to 10% by weight, preferably 0.01 to 1.0% by weight.

-15=If the amount of the catalyst used is less than 0.001% by weight, the effect will be small; on the contrary, it is not necessary to use the amount exceeding 10% by weight.

Heating is performed at room temperature to 200°C, preferably 40 to 130°C.
C, and the reaction time is determined by the reaction temperature and the reactivity of the saturated or unsaturated alcohol.
Generally, 1 to 20 hours is suitable.

Through the above reaction, a portion of the acid anhydride groups in the copolymer is esterified to generate free carboxylic acid groups.

When this carboxylic acid group moiety is esterified with an alcohol as described above, water is produced.

It is known that in this type of esterification reaction, unless the produced water is removed from the system, the reaction will not proceed quickly due to an equilibrium reaction.

To remove water from this reaction system, it is possible to remove only water by heating, but for example, aromatic compounds such as benzene, toluene, xylene, esters such as ethyl acetate, methyl acetate, etc. Water can be distilled off by adding a substance that does not dissolve in the reaction system as an entrainer and performing azeotropic dehydration.

The amount of solvent added is preferably 0.3 parts or more based on the total volume.

It is desirable to separate the azeotropic solvent/water outside the system and reuse the separated solvent.

The dehydration esterification reaction with alcohol may be carried out under normal pressure, increased pressure, or reduced pressure.

The reaction response ranges from 20°C to 200°C, preferably from 50°C to 1
Within the range of 50°C, the reaction time varies depending on the type of alcohol used in the esterification reaction, but is 1 to 3
0 hours, preferably within the range of 3 to 20 hours.

At this time, in order to promote the reaction, P-toluenesulfonic acid, lithium acetate, quaternary ammonium salt, tertiary amine zinc, carboxylate salt thereof, etc. may be used as a catalyst. The amount used is as described above.

The alcohols used include compounds with double bonds such as allyl alcohol/2-hydroxyethyl methacrylate, 2-droxyethyl acrylate, droxypropyl acrylate, and droxypropyl methacrylate, as well as 2,3-dibromo- 1-propanol, propyl alcohol, hexyl alcohol, octyl alcohol, and benzyl alcohol can be used.

As shown in the above reaction formula, various partial alcohols,
In particular, alcohols having vinyl groups and the like and non-reactive alcohols can be freely introduced onto the chain.

In addition, in the above reaction, ■ Reaction of α, β-unsaturated carboxylic acid anhydride-vinyl compound copolymer and saturated or unsaturated alcohol and ■ α, β-Unsaturated carboxylic acid anhydride-vinyl compound copolymer It is also possible to react the partially esterified product of and the unsaturated or saturated alcohol at the same time.

Furthermore, the saturated or unsaturated alcohols used for esterification of carboxyl groups may be a mixture of two or more types.

In addition, as a reaction solvent, a predetermined amount of these high boiling point solvents is placed in a reactor, raw material resin and alcohol chain are added, and in addition, a necessary amount of toluene is added as an azeotropic dehydration solvent, and toluene/water is distilled off. After the reaction is completed, it is also possible to distill off only the added toluene again and take out the remaining residue product as a raw material for the next step.

Next, a resin in which the side chain in the α,β-unsaturated carboxylic acid skeleton obtained as described above is a mixture of (a) a carboxyl group, (b) an unsaturated alcohol ester group, and (c) a saturated alcohol ester group was prepared. The following reaction is carried out by dehydrating and esterifying a part of the carboxyl group using a dihydric alcohol (however, side reactions also occur, so the following product is just an example).

Cross-linking esterification reaction of a part of the carboxyl group of the reaction product (■) using a dihydric alcohol (Some of the reaction products of (■) have some remaining carboxyl groups.Remaining amount of carboxyl group can be quantified by measuring the acid value, X, y, and 2 can be interchangeable or the same, R and R3 can be interchangeable or the same, double bond. (The residue of a compound having the following can be quantified by measuring the iodine value.) The reaction (2) can also be carried out simultaneously with the reaction (2) or the reaction (2).

The following dihydric alcohols can be used.

Ethylene glycol, 1.3-butanediol, 1.4
-butanediol, 1.5-hexanediol, 1.6
-hexanediol, 2.2.4-trimethylhexanediol, cyclohexalinemethanol, etc.

The reaction conditions are as follows.

The reaction pressure may be normal pressure, increased pressure or reduced pressure, and the reaction temperature is 20 to 200°C, preferably 5o to 150°C.

The reaction time varies depending on the type of alcohol used for esterification, but is in the range of 1 to 30 hours, preferably 3 to 2'0 hours.

It is also possible to use catalysts such as p-toluenesulfonic acid, lithium acetate, quaternary ammonium salts, tertiary amines, zinc, or their carboxylic acid salts to accelerate the reaction.

The amount of dihydric alcohol used is approximately 0.01 to 0.5 mol per mol of carboxylic group, and 0.02 to 1' mol per mol of acid anhydride, to achieve the desired production. It can vary widely depending on the properties required for the product.

This reaction is also a Nisderization reaction, similar to the esterification reactions (1) and/or (2), which are carried out to block carboxyl groups with monohydric alcohols, so it is necessary to remove the water produced to accelerate the reaction. is preferred.

To remove water from this reaction system, it is possible to remove only water by heating, but for example, aromatic compounds such as benzene, toluene, xylene, esters such as ethyl acetate, methyl acetate, etc. Water can be distilled off by adding a substance that does not dissolve in the reaction system as an entrainer and performing azeotropic dehydration.

The amount of solvent added is preferably 0.3 parts or more based on the total volume.

It is desirable to separate the azeotropic dissolved W/water outside the system and reuse the separated solvent.

The properties of the resin vary greatly depending on the amount of dihydric alcohol added.

For example, when adding 0.1 mole of 1.6 hexanediol to 1 mole of monocarboxylic acid and when adding 0.5 mole, the viscosity of the resin will be greater when 0.5 mole is added. Become.

Also, for example, if cyclohexaline methanol is added instead of 1.6 hexanediol, the resin will be 1.6
Harder than hexanediol.

In this way, the viscosity and hardness can be freely changed by changing the amount and type of dihydric alcohol added.

By the method described above, it is possible to obtain a compound having a structure whose polymerizability and viscosity can be varied in various ways.

Example-1 Into a 2J separable flask equipped with a stirrer, thermometer, dehydration tube, and reflux condenser, 600 gr, α, β-
As an unsaturated carboxylic anhydride-vinyl compound copolymer, a styrene-maleic anhydride copolymer saturated alcohol homoadduct (SMA1 manufactured by Arco Chen+1ca1) was used.
440) To 600g, add 32g of allyl alcohol as an unsaturated alcohol, 14.2g of 1.6-hexane-24=diol as a dihydric alcohol as a crosslinking agent, and 0.6g of para-toluenesulfonic acid as an esterification dehydration catalyst. 10 at 110℃
A time dehydration esterification reaction was performed.

After the reaction was completed, toluene was distilled off at 50° C. and 20 nmHg, and the resin was taken out.

About 25% of allyl alcohol had reacted.

This resin had an excellent balance between crosslinking properties and solubility in solvents.

Example-2 The same procedure as Example-1 was carried out except that 87 g of cyclohexaline methanol was used instead of 1,6-hexanediol, and the acid value was 152, the allyl alcohol addition rate was 20%,
A product was obtained in which 1 mole of cyclohexalinemethanol was added to 4 moles of carboxyl basis.

The crosslinkability of this product was similar to that of the resin obtained in Example-1, but it was a somewhat hard resin.

Comparative Example 1 A resin with an acid value of 124 was obtained in the same manner as in Example 1, except that 1,6-hexanediol, which is a dihydric alcohol, was not used so as not to crosslink the carboxyl groups.

This resin showed high solubility in dipropylene glycol monomethyl ether acetate, but was inferior to the product of Example-1 in terms of crosslinkability.

Comparative Example-2 In a 2" separable flask equipped with a stirrer, thermometer, dehydration tube, and reflux condenser, 400 gr of methyl ethyl,
100g of allyl alcohol as unsaturated alcohol
, styrene-maleic anhydride copolymer (Arc
o SMA100O manufactured by ChelniCa1) 500g
r ester esterification dehydration catalyst latoluenesulfonic acid 0
．． 6 gr was added, and the dehydration esterification reaction was carried out at 80° C. for 5 hours.

After the reaction was completed, toluene was distilled off at 50° C. and 20 nmHg, and the resin was taken out.

The acid value of the obtained resin was 334, and about 23% of allyl alcohol had reacted.

This resin had poor solubility and crosslinkability in both dipropylene glycol monomethyl ether acetate and dipropylene glycol monomethyl ether acetate.

Claims (6)

[Claims] (1) The basic skeleton is an α,β-unsaturated carboxylic acid anhydride-vinyl compound copolymer, and the side chains in the α,β-unsaturated carboxylic acid skeleton are (a) carboxyl groups (b) unsaturated alcohol ester groups (c) A curable resin in which a portion of the carboxyl groups of a resin that is a mixture of saturated alcohol ester groups is crosslinked and esterified with a dihydric alcohol. (2) The curable resin according to claim (1), wherein the unsaturated alcohol is any one selected from allyl alcohol, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate. (3) Saturated alcohol is propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol,
The curable resin according to claim (1), which is any one selected from 2-3-dichloro-1-propanol and 2,3-dibromo-1-propanol. (4) The curable resin according to claim (1), wherein the α,β-unsaturated carboxylic acid anhydride is maleic anhydride. (5) The vinyl compound is styrene, 2-methylstyrene,
The curable resin according to claim (1), which is any one selected from acrylic esters, methacrylic esters, vinyl acetate, acrylonitrile, and vinyl chloride. (6) The dihydric alcohol is ethylene glycol, 1,3-
Butanediol, 1,4-butanediol, 1,5-hexanediol, 1,6-hexanediol, 2,2,
The curable resin according to claim (1), which is any one selected from 4-trimethylhexanediol and cyclohexalinemethanol.