JPS6346761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel industrially useful reactive polymer. Specifically, the present invention relates to a method for producing a reactive polymer by reacting a polymer containing a free carboxylic acid group with an aziridine compound having an unsaturated group.

"Reactive polymer" as used herein
The term refers to a polymer having a reactive group that "can undergo or participate in a so-called radical reaction" under the action of heat, ultraviolet light, electron beams, free radical generating agents, and the like. Heretofore, several proposals have been made as methods for producing such reactive polymers. One of these uses the so-called esterification reaction, for example, the reaction of a polymer containing free carboxylic acid groups with an unsaturated hydroxyl compound or an unsaturated glycidyl compound, or the reaction of a polymer containing a hydroxyl group or a glycidyl group. A method is known that utilizes the reaction between carbon dioxide and an unsaturated carboxylic acid compound. However, in the esterification reaction, the reactants are generally kept under harsh temperature conditions for a relatively long period of time, so side reactions such as polymerization of unsaturated groups are likely to occur during the reaction. As a means to reduce such risks, measures such as adding a large amount of polymerization inhibitor to the reaction system, introducing oxygen, and relaxing reaction conditions by using an esterification reaction catalyst are known, but the resulting reaction Polymers often contain excessive amounts of polymerization inhibitors and catalyst residues, which can cause coloring and reaction delays depending on the intended use.
Only low quality evaluations are given.

Another known method utilizes a urethanization reaction, such as a method in which a polymer having a hydroxyl group and an unsaturated hydroxyl compound are bonded via a diisocyanate compound.
However, in this case as well, in addition to the use of a catalyst, typically an organotin compound, to promote the reaction, the hydroxyl groups of the polymer and the hydroxyl groups of the unsaturated compound, and the isocyanate groups of one of the diisocyanate compounds and the isocyanate group of the other It is difficult to selectively react each of the groups, and in order to increase the selectivity of the reaction, a plurality of reaction steps must be performed sequentially, which has the disadvantage of complicating production.

As a result of intensive research to solve the drawbacks of such conventionally known methods, the present inventors discovered that the free carboxylic acid groups in a polymer containing free carboxylic acid groups and the aziridine groups in a specific unsaturated aziridine compound The present invention was completed by discovering that a reactive polymer can be obtained by reacting the following in a specific ratio.

It is therefore an object of the present invention to provide a reactive polymer having a reactive group "capable of causing or participating in a radical reaction" and a method for producing the same.

That is, the present invention comprises a polymer (A) containing free carboxylic acid groups in an acid equivalent ratio of 0.01 to 5 milliequivalents/g and an unsaturated aziridine compound (B) represented by the following general formula.
and 0.05 to 1.0 of the unsaturated aziridine compound (B) per 1.0 mol of free carboxylic acid groups of the polymer (A).
It relates to the production of reactive polymers characterized in that they are reacted in ratios in the molar range.

general formula (However, in the formula, R ₁ is hydrogen or a methyl group,
_R2 to _R5 are selected from the group consisting of hydrogen and an alkyl group having 1 to 4 carbon atoms, and may be the same or different. ) The polymer (A) containing free carboxylic acid groups used in the present invention is a polymer containing free carboxylic acid groups at an acid equivalent ratio of 0.01 to 5 meq/g. Such polymers (A) include acrylic acid,
Conventionally, polymerizable monomers containing free carboxylic acid groups such as methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, etc., or a mixture thereof, and an unsaturated monomer copolymerizable with these monomers are used. A copolymer obtained by polymerizing according to a known method; A homopolymer or a copolymer obtained by polymerizing an unsaturated monomer that produces a carboxyl group by hydrolysis using a conventionally known method. Polymers containing free carboxylic acid groups; Polymers containing free carboxylic acid groups introduced using known polymerization initiators, chain transfer agents, polymerization terminators, etc. containing free carboxylic acid groups; Phthalic anhydride polyester polycarboxylic acid obtained by the condensation reaction of polyhydric carboxylic acids such as acid, maleic anhydride, terephthalic acid, etc. and polyhydric alcohols such as ethylene glycol, propylene glycol; Examples include alkyd polycarboxylic acids obtained by polymerization reactions; maleated petroleum resins; starches and celluloses containing carboxylic acid groups; and polyethylene glycol dicarboxylic acids.

Examples of unsaturated monomers copolymerizable with the free carboxylic acid group-containing polymerizable monomers include methyl esters, ethyl esters, propyl esters, butyl esters of unsaturated monobasic acids such as acrylic acid and methacrylic acid; Esters such as 2-ethylhexyl ester, hydroxyethyl ester, hydroxypropyl ester; acrylamide, methacrylamide, their N-substituted acrylamides and methacrylamide; methyl alcohol, ethyl alcohol of unsaturated dibasic acids such as maleic acid and itaconic acid , mono- and diesters with lower alkyl alcohols such as propyl alcohol; one or more unsaturated monomers such as acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, vinylidene chloride, styrene, ethylene, butadiene, etc. Can be used.

If the amount of free carboxylic acid groups contained in the polymer (A) is less than 0.01 meq/g, the polymer
A substantially effective amount of reactive unsaturated groups cannot be introduced into (A). Further, if the amount is more than 5 milliequivalents/g, the cured product derived from the resulting reactive polymer will be extremely hard and brittle, which is not preferable.

The unsaturated aziridine compound (B) used in the present invention is represented by the above general formula.
Such unsaturated aziridine compounds (B) include:
2-(1-aziridinyl)ethyl acrylate,
2-(1-aziridinyl)ethyl methacrylate,
2-[1-(2-methylaziridinyl)]ethyl acrylate, 2-[1-(2-methylaziridinyl)]ethyl methacrylate, 2-[1-(2.2-dimethylaziridinyl)]ethyl acrylate ,2
-[1-(2.2-dimethylaziridinyl)]ethyl methacrylate, 2-[1-(2-ethylaziridinyl)]ethyl acrylate, 2-[1-(2-ethylaziridinyl)]ethyl methacrylate, etc. are mentioned, and one or more of these can be effectively used. Among them, the preferred one is 2-
(1-aziridinyl)ethyl methacrylate (for example, “Chemitite MZ” manufactured by Nippon Shokubai Chemical Co., Ltd.)
−11”).

The method for producing a reactive polymer in the present invention is to
(A) Free carboxylic acid group and unsaturated aziridine compound
Based on the aminoesterification reaction with the aziridine group of (B). However, in this reaction system, it is predicted that not only such an aminoesterification reaction but also a ring-opening polymerization reaction between aziridine groups will proceed competitively. Simultaneous ring-opening polymerization reactions between aziridine groups reduce the rate of addition of the unsaturated aziridine compound (B) to the free carboxylic acid groups of the polymer (A), which in turn reduces the usefulness aimed at in the production of the present invention. The yield of reactive polymer becomes significantly lower.

The present inventors conducted studies to solve this problem, and the present invention was achieved as a result.

In the present invention, the unsaturated aziridine compound (B) is added to 1.0 mol of free carboxylic acid groups of the polymer (A).
It must be reacted in proportions ranging from 0.05 to 1.0 mol. If the amount of the unsaturated aziridine compound (B) is less than 0.05 mol per 1.0 mol of the free carboxylic acid group, the concentration of reactive unsaturation in the resulting reactive polymer will be low, making it impractical. Furthermore, when the free carboxylic acid group is reacted with more than an equimolar amount of the unsaturated aziridine compound (B), the ring-opening polymerization reaction between the aziridine rings increases in parallel with the aminoesterification reaction, as described above. However, useful reactive polymers cannot be obtained. In the production method of the present invention, it is more preferable that the unsaturated aziridine compound (B) is reacted at a ratio of 0.1 to 0.5 mol per 1.0 mol of free carboxylic acid groups of the polymer (A).

In the production method of the present invention, the aminoesterification reaction proceeds even at room temperature, that is, at a low temperature of about 20°C, but a ring-opening reaction between aziridine groups is also observed at temperatures below about 40°C.

Therefore, in order to prioritize the aminoesterification reaction in the production method of the present invention, it is preferable to carry out the reaction at a temperature of about 40°C or higher. The upper limit temperature of the reaction cannot be specified depending on the polymer used, the type and amount of polymerization inhibitor, the oxygen concentration of the reaction atmosphere, etc., but it depends on the stability of the polymerizable unsaturated group of the unsaturated aziridine compound (B) and the yield Considering the stability and coloring of the reactive polymer, the temperature is 150°C. Therefore, the preferred temperature range is 40-150°C, more preferably
The temperature is 40-110℃.

During the reaction, if the fluidity of the polymer (A) is low or in order to facilitate the addition of the unsaturated aziridine compound (B) to the reaction system, the polymer (A) and/or the unsaturated aziridine compound (B) may be added to the reaction system. Applying a diluent to is the preferred method. The diluent is a compound capable of dissolving or dispersing both the polymer (A) and the unsaturated aziridine compound (B). Examples include aromatic hydrocarbons such as benzene, toluene, xylene, and chlorobenzene, dioxane, methyl ethyl ketone, ethyl acetate, cellosolves, carbitols, alcohols, and water. Furthermore, polymerizable monomers such as styrene, acrylonitrile, vinyl acetate, acrylic esters, and methacrylic esters can also be used.

Furthermore, in order to carry out the present invention more safely and obtain a reactive polymer, hydroquinone is added before or after the reaction to introduce oxygen into the reaction system and to ensure long-term stability of the reactive polymer. Methoquinone,
It is also a preferred embodiment to add a known polymerization inhibitor such as phenothiazine.

The reactive polymer obtained by carrying out the present invention can be used as a chain lengthening agent, blocking agent, etc. in various fields such as adhesives, coating agents, fillers, and molding materials.
It is used as a grafting agent and crosslinking agent and exhibits excellent performance.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that "parts" in the examples represent parts by weight.

Example 1 NISSO-PB・C-1000 (free carboxylic acid group content 1.48 meq/g, liquid polybutadiene dicarboxylic acid, manufactured by Nippon Soda) 250 was placed in a reactor equipped with a stirrer, a cooler, a thermometer, and a dropping funnel. of the mixture and the temperature was adjusted to 60°C while stirring. Then from the dropping funnel 31.6
“Chemitite MZ-11” (2-(1-aziridinyl)ethyl methacrylate, manufactured by Nippon Shokubai Chemical)
was continuously added dropwise over 3 hours, kept at the same temperature for another 3 hours, and cooled to obtain a product. As a result of carboxylic acid group concentration analysis by titration, this product was liquid polybutadiene in which 48% of the free carboxylic acid groups in the raw material had been converted to unsaturated groups.

Example 2 250 parts each of NISSO-PB・C-1000 and toluene were placed in a reactor equipped with a stirrer, a cooler, a thermometer, and a dropping funnel, and the contents were dissolved under stirring and heated to 70°C.
It was adjusted to Then, at the same temperature, 26.0
of 2-(1-aziridinyl)ethyl acrylate was continuously added dropwise over 3 hours, and the mixture was kept at the same temperature for 3 hours. After cooling, the contents were taken out and toluene was removed using an evaporator to obtain a product.
As a result of carboxylic acid group concentration analysis by titration, this product was liquid polybutadiene in which 49% of the free carboxylic acid groups in the raw material had been converted to unsaturated groups.

Example 3 In a reactor equipped with a stirrer, a condenser, a thermometer, and a dropping funnel, the monomer composition obtained by a conventional method was butyl acrylate/methacrylic acid = 90/10.
A 50% by weight toluene solution of a copolymer with a free carboxylic acid group content of 1.16 meq/g (weight ratio) 500
of the mixture, and the internal temperature was adjusted to 90°C while stirring. Next, 50% of “Chemitite MZ-11” was added from the dropping funnel.
22.5 parts of 45 parts of toluene solution were added dropwise in the first hour and the remaining 22.5 parts in the next 2 hours, and the mixture was further kept at the same temperature for 2 hours and cooled. Toluene was removed from the contents taken out using an evaporator to obtain a product. As a result of unsaturation concentration analysis using the HBr method, the product was found to contain reactive unsaturated groups.
It contained 0.51 mmol/g.

Example 4 An alkyd resin with a free carboxylic acid group content of 1.0 meq/g obtained from glycerin, phthalic anhydride and fatty acid was added in a conventional manner to a reactor equipped with a stirrer, a condenser, a thermometer and a dropping funnel. 500 parts of a xylene solution containing 40% by weight was added, and the temperature of the contents was adjusted to 70°C while stirring. Next, 6.4 parts of "Chemitite MZ-11" was continuously dropped from the dropping funnel over 1.5 hours, and the mixture was kept at the same temperature for another 4 hours, after cooling.
A product containing a resin content of 41% by weight was obtained. Analysis of the carboxylic acid group concentration by titration of the resin content in the product revealed that 20% of the free carboxylic acid groups in the raw material had been converted to reactive unsaturated groups.

Example 5 In a reactor equipped with a stirrer, a condenser, a thermometer and a dropping funnel, the amount of free carboxylic acid groups was 0.71 meq/
85 parts of Nipol-1072B (carboxylated acrylonitrile-butadiene rubber, manufactured by Nippon Zeon), 415 parts of methyl methacrylate, and phenothiazine
After adding 0.001 part and allowing the rubber to swell overnight,
The rubber was dissolved at 90°C under stirring. Then the contents
Adjust the temperature to 70℃ and add “Chemitite MZ” from the dropping funnel.
Methyl methacrylate solution containing 10% by weight of −11”
23.4 parts of 46.8 parts were added dropwise in the first hour, and the remaining 23.4 parts were added dropwise in the next 2 hours. The mixture was kept at the same temperature for another 3 hours, and then cooled to form a methyl methacrylate solution with a resin content of 16.5%. Obtained. Analysis of the carboxylic acid group concentration by titration of the resin content in the solution revealed that approximately 45% of the free carboxylic acid groups in the raw rubber had been converted to reactive unsaturated groups.

Example 6 A reactor equipped with a stirrer, a cooler, a thermometer, and a dropping funnel was charged with a monomer composition of acrylonitrile/butyl acrylate/butyl acrylate obtained by a known emulsion polymerization method.
Add 200 parts of a 50% by weight aqueous dispersion of a resin with a free carboxylic acid group content of 0.69 meq/g of acrylic acid = 13.5/81.5/5.0 (weight ratio), and reduce the contents to 70% by weight while stirring.
The temperature was adjusted to ℃. Next, 5.4 parts of "Chemitite MZ-11" was continuously added dropwise from the dropping funnel over 1.5 hours, kept at the same temperature for 4 hours, and cooled to obtain an aqueous dispersion containing 51% by weight of resin. As a result of carboxylic acid group concentration analysis of the resin content by titration, approximately 37% of the free carboxylic acid groups in the raw material were converted to reactive unsaturated groups.

Claims (1)

[Scope of Claims] 1. A polymer (A) containing free carboxylic acid groups in an acid equivalent ratio of 0.01 to 5 milliequivalents/g and an unsaturated aziridine compound (B) represented by the following general formula, 1. A method for producing a reactive polymer, which comprises reacting the unsaturated aziridine compound (B) at a ratio of 0.05 to 1.0 mol with respect to 1.0 mol of free carboxylic acid groups of the polymer (A). general formula (However, in the formula, R ₁ is hydrogen or a methyl group,
_R2 to _R5 are selected from the group consisting of hydrogen and an alkyl group having 1 to 4 carbon atoms, and may be the same or different. ).