JP2001348419A - Recyclable epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting resin composition which, while retaining the workability inherent in a thermosetting resin, can be recycled by softening and melting under heating just like a thermoplastic resin and to thereby solve the problem that a thermosetting resin is difficult to recycle. SOLUTION: This recyclable epoxy resin composition comprises (A) an epoxy resin having an average functionality of 1.5-2.2 and (B) at least one compound which has two epoxy-reactive functional groups and is selected from among amine compounds, phenol compounds, and thiol compounds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a recyclable epoxy resin composition.

[0002]

2. Description of the Related Art An uncured product obtained by kneading a putty-like composition using an epoxy resin as a main component and a curing agent such as a polyamine, a polyamidoamine, or a polymercaptan to produce a master model or a jig. Is applied to a shape close to a master model or a jig and hardened, and is cut into a desired shape by cutting with an NC processing machine or manual cutting with a chisel, a canner, or the like. Then, for the recycling of the manufactured master model or jig, after use, it is pulverized and reused as a filler of the same material (Japanese Patent Application Laid-Open No. 9-124949), and hydrolyzed using supercritical water or subcritical water as a solvent. Alternatively, a low to medium molecular compound that can be reused by thermal decomposition is recovered (JP-A-10-24274, JP-A-10-287).
766) has been proposed.

[0003] However, when reused as a filler, only a limited type of filler can be produced, which limits the use of the filler. In addition, hydrolysis or supercritical water or subcritical water is used as a solvent for hydrolysis or sublimation. It is economically difficult to recover a low to medium molecular compound that can be reused by pyrolysis, and it has not been widely used.

[0004] However, the production of a master model or a jig requires the property of being able to work at room temperature. Therefore, in the production of a master model or a jig, a main agent and a curing agent are kneaded to obtain a desired shape. An epoxy resin composition which is hardened at room temperature or by heating after being provided is used, and it is extremely difficult to use a thermoplastic resin which is molded by heat melting in place of the epoxy resin composition.

[0005] A molded article made of a thermoplastic resin such as PET or polyvinyl chloride is softened and melted by heat after use, and is reused as a plastic raw material.

[0006]

SUMMARY OF THE INVENTION The present invention provides a thermosetting resin composition which can be recycled by being softened and melted by heat, such as a thermoplastic resin, while maintaining the workability of the thermosetting resin. The present invention has been made to solve the problem that recycling of thermosetting resins is difficult.

[0007]

The present invention provides an epoxy resin (A) having an average number of functional groups of 1.5 to 2.2 and an amine compound having two functional groups capable of reacting with an epoxy group.
A recyclable epoxy resin composition (Claim 1) comprising at least one (B) of a phenolic compound and a thiol compound, having an average number of functional groups of 1.5 to 2.2.
Recycled from at least one epoxy resin (A), an amine compound having two functional groups capable of reacting with an epoxy group, a phenol compound and a thiol compound (B) and a thermoplastic resin (C) A possible epoxy resin composition (Claim 2), the epoxy resin composition according to Claim 1 or 2 further comprising a filler (D) (Claim 3), and a claim used for the production of a master model or a jig. An epoxy resin composition according to claim 1, 2 or 3 (claim 4).

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxy resin composition of the present invention comprises:
After using a cured product is a thermosetting resin composition, despite having the workability of the thermosetting resin composition,
It is a thermosetting resin composition that can be recycled by being softened and melted by heat like a thermoplastic resin molded product.

The epoxy resin composition comprises an epoxy resin (A) having an average number of functional groups of 1.5 to 2.2 (hereinafter also referred to as epoxy resin (A)) and two functional groups capable of reacting with the epoxy group. A composition comprising at least one compound (B) (hereinafter, also referred to as a compound (B)) of an amine compound, a phenol compound and a thiol compound having an impact resistance and a softening / melting property, if necessary. And a filler (D) which is a component for improving the machinability and compressive strength and decreasing the linear expansion coefficient.

The epoxy resin used in the epoxy resin composition may be any of the conventionally used resins which are liquid or solid at room temperature, especially having an average number of functional groups of 1.5 to 2.2. Further, the use of 1.8 to 2.0 epoxy resins (A) is a simple process of softening and melting the cured product after use by heat, and cooling and solidifying it into an arbitrary shape. It is to be able to recycle just by doing. When an epoxy resin having an average of less than 1.5 functional groups is used, curing with the compound (B) results in heat resistance, abrasion resistance, impact resistance, and the like of the cured product. Insufficient, when using more than 2.2, there is no problem of heat resistance, abrasion resistance, impact resistance, etc. of the cured product, but it is difficult to recycle, and the conventional epoxy resin composition Or similar to conventional epoxy resin compositions.

The average value of 1.5 to 2.2 functional groups of the epoxy resin is defined as the main component of the epoxy resin (50% by weight or more, hereinafter referred to as%), and moreover 80%.
The above means that a bifunctional epoxy resin is used, and if necessary, a trifunctional or higher functional epoxy resin, a monofunctional reactive diluent is contained, and the average value of the functional groups is 1.5 to 2.2. .

Specific examples of the bifunctional epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bifunctional phenol novolak epoxy resin, bisphenol AD epoxy resin, biphenyl epoxy resin, and bifunctional epoxy resin. Naphthalene type epoxy resin, bifunctional alicyclic epoxy resin, bifunctional glycidyl ester type epoxy resin (for example, diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl ester of dimer acid, etc.), and bifunctional glycidylamine type epoxy resin ( For example, diglycidyl aniline, diglycidyl toluidine, etc.) bifunctional heterocyclic epoxy resin, bifunctional diaryl sulfone type epoxy resin, hydroquinone type epoxy resin (eg, hydroquinone diglycide) Ether, 2,5-di -te
tert-butylhydroquinone diglycidyl ether, resorcin diglycidyl ether, etc.) bifunctional alkylene glycidyl ether-based compound (for example, butanediol diglycidyl ether, butenediol diglycidyl ether, butynediol diglycidyl ether, etc.) bifunctional glycidyl group Hydantoin-containing compounds (eg, 1,3-diglycidyl-5,5-dialkylhydantoin, 1-glycidyl-3- (glycidoxyalkyl) -5,5-dialkylhydantoin), 2
Functional glycidyl group-containing siloxanes (eg, 1,3-
Bis (3-glycidoxypropyl) -1,1,3,3-
Tetramethyldisiloxane, α, β-bis (3-glycidoxypropyl) polydimethylsiloxane, etc.) and modified products thereof. Of these,
Bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred from the viewpoint of reactivity and workability.

Specific examples of the above trifunctional or higher functional epoxy resin include trifunctional or higher functional phenol novolak type epoxy resin, trifunctional or higher functional alicyclic epoxy resin, trifunctional or higher functional glycidyl ester type epoxy resin,
Trifunctional or higher glycidylamine type epoxy resin (for example, tetraglycidyldiaminodiphenylmethane, triglycidyl-p-aminophenylmethane, triglycidyl-m-aminophenylmethane, tetraglycidyl-m-
Xylylenediamine, etc.) trifunctional or higher functional heterocyclic epoxy resin, trifunctional or higher functional diaryl sulfone epoxy resin, trifunctional or higher functional alkylene glycidyl ether compound (for example, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, penta Erythritol tetraglycidyl ether, etc.), trifunctional or higher glycidyl group-containing hydantoin compounds, trifunctional or higher glycidyl group-containing siloxanes, and modified products thereof.

Examples of the monofunctional reactive diluent include tert-butylphenylglycidyl ether,
-Ethylhexyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 1- (3-glycidoxypropyl) 1,1,3,3 Monoglycidyl compounds such as 2,3-pentamethyldisiloxane, N-glycidyl-N, N-bis [3- (trimethoxysilyl) propyl] amine and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Monoalicyclic epoxy compounds and the like can be mentioned.

At least one of the amine compound, phenol compound and thiol compound (B) (compound (B)) having two functional groups capable of reacting with the epoxy group is a compound of the epoxy resin (A). Since it is a component used as a curing agent and is bifunctional, the average number of functional groups of the epoxy resin (A) is 1.5 to 2.2, and a linear polymer is formed by an addition reaction. Generate. As a result, while maintaining the workability of the thermosetting resin,
Recycling becomes possible by softening and melting by heat like a thermoplastic resin, and the problem that recycling of a thermosetting resin is difficult can be improved.

The compound (B) has a molecular weight of 50 to 10
From the viewpoint of workability, those which are liquid or semi-solid at room temperature, and more preferably 100 to 500 are preferable.

The amine compound is preferably a liquid at room temperature. Specific examples of the amine compound include, for example, piperazine, dodecylamine, benzylamine, dimethylaminopropylamine and the like. These may be used alone or in combination of two or more.

The phenolic compound is preferably a compound having a low viscosity at the time of melting, a low crystallinity, and not crystallizing when a required amount as a curing agent is dissolved in the epoxy resin (A). Specific examples of the phenolic compound include mononuclear aromatic dihydroxy compounds having one benzene ring such as catechol, resorcin, and hydroquinone; bis (4-hydroxyphenyl) propane (bisphenol A); Bisphenols such as hydroxyphenyl) methane (bisphenol F) and bis (4-hydroxyphenyl) ethane (bisphenol AD); compounds having a condensed ring such as dihydroxynaphthalene; allyls such as diallyl resorcinol, diallyl bisphenol A and triallyl dihydroxy biphenyl Examples thereof include a bifunctional phenol compound into which a group has been introduced, and dibutyl bisphenol A. These may be used alone or in combination of two or more.

The thiol compound is preferably a liquid at room temperature. Specific examples of the thiol-based compound include, for example, ethylene glycol bisthioglycolate, ethylene glycol bisthiopropionate, and the like. These may be used alone or in combination of two or more.

The amine compounds, phenol compounds and thiol compounds may be used alone or in combination of two or more.

In the composition of the present invention comprising the epoxy resin (A) and the compound (B), the proportion of the epoxy resin (A) and the compound (B) used is 1 equivalent of the epoxy resin (A) and the compound (B). ) 0.8 to 1.2 equivalents, more preferably 0.9 to 1.1 equivalents, from the viewpoint of reflowability and heat resistance.

A thermoplastic resin (C) may be added to the composition of the present invention comprising the epoxy resin (A) and the compound (B) in order to further improve impact resistance and softening / melting properties. .

The thermoplastic resin (C) has a particle diameter of 1 to 1.
A 200 μm powder that can be filled in the same way as a normal filler and that can be softened and melted by heating can be used. Specific examples thereof include polyethylene powder, polyvinyl chloride powder, and thermoplastic polyurethane powder (TPU). Of these, thermoplastic polyurethane powders (TP
U) is preferred.

The epoxy resin (A), the compound (B) and, if necessary, the thermoplastic resin (C) used
A filler (D) may be added to the composition of the present invention for improving the compressive strength, low thermal expansion property and machinability.

As the filler (D), any filler used in ordinary epoxy resin compositions can be used, and there is no particular limitation. As a specific example,
For example, silica sand, talc, calcium carbonate, mica, acid clay, diatomaceous earth, kaolin, quartz, titanium oxide, silica,
Carbon black, phenolic resin micro balloon,
Glass balloons and the like can be mentioned.

The mixing amount of the thermoplastic resin (C) with respect to 100 parts by weight (hereinafter referred to as "parts") of the composition of the present invention comprising the epoxy resin (A) and the compound (B) is 50 parts or less in terms of viscosity. And more preferably 30 parts or less. The lower limit is preferably 10 parts or more from the viewpoint that a clear effect can be obtained by using the thermoplastic resin (C).

The amount of the filler (D) to be added to 100 parts of the composition of the present invention comprising the epoxy resin (A) and the compound (B) is 300 parts or less, and more preferably 200 parts or less.
Parts or less are preferred. The lower limit is preferably 30 parts or more from the viewpoint that a clear effect can be obtained by using the filler (D).

The above-mentioned composition of the present invention may further contain components generally added to the epoxy resin composition, such as a curing accelerator, a silane coupling agent and an antifoaming agent.

The composition of the present invention as described above can be used, for example, for producing master models, jigs and the like. When used for master models, jigs and tools, it is easy to recover after use, and has the workability of thermosetting resin, but it is a simple operation of softening and melting by heat like thermoplastic resin. Can be recycled.

[0030]

EXAMPLES Next, the composition of the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

First, raw materials used in Examples and Comparative Examples and evaluation methods will be described.

[Raw materials] (Epoxy resin (A)) AER260: manufactured by Asahi Chiba Co., Ltd., trade name, bisphenol A type epoxy resin, two functional groups, number average molecular weight 38
0 XN1034: Nagase ChemteX Corporation, trade name,
Polypropylene glycol diglycidyl ether, epoxy equivalent 320

(Compound (B)) Ultralite P: Honshu Chemical Co., Ltd., trade name, dibutyl bisphenol AEGTG: Yodo Chemical Co., Ltd., trade name, ethylene glycol bisthioglycolate

(Thermoplastic resin (C)) KA8823: Desmomert KA8823, trade name, manufactured by Sumitomo Bayer Urethane Co., Ltd., thermoplastic polyurethane powder, particle diameter 1 to 80 μm, softened and melted by heating

(Filler (D)) Talc: manufactured by Nippon Talc Co., Ltd., trade name: TALC-MS Glass balloon 1: manufactured by Asahi Glass Co., Ltd., trade name: CEL-S
TAR CZ-31T Glass balloon 2: CEL-S, manufactured by Asahi Glass Co., Ltd.
TAR Z-36

(Curing Accelerator) TOTP: manufactured by Hokuko Chemical Co., Ltd., trade name, tolyl phosphine TMAC: manufactured by Nippon Special Chemical Industry Co., Ltd., trade name, tetramethylammonium chloride TBZ: manufactured by Shikoku Chemical Industry Co., Ltd. , Trade name Curesol T
BZ, benzimidazole derivative

(Other curing agents) HY956: trade name HA manufactured by Nagase ChemteX Corporation
RDENER HY956, modified aliphatic polyamine, average number of functional groups 5 to 7

[Evaluation Method] (Curability) Each resin composition was heated at a temperature corresponding to the type of curing agent.
After reacting for a time, the cured product was cooled to room temperature, and the degree of surface curing was evaluated by finger touch. ○: sufficiently cured, no tack ×: insufficient curing, tacked

(Reflowability and reflowability temperature) The cured product of the resin composition whose curability was evaluated was heated on a hot plate, and the reflowability was evaluated according to the following criteria, and the temperature at which reflowability was measured. did. ：: Sufficient reflow, no shape retention ×: Insufficient reflow, shape retention

(Recyclability and Recycling Temperature) The cured product of the putty-like resin composition is heated in a hot air circulation oven, softened and melted, molded into a rough shape of a model or a jig, and cooled to room temperature. Cutting with woodworking tools and surface polishing with sandpaper are performed. If cutting and surface polishing are possible, there is recyclability (○). If not, there is no recyclability (×). Softening and melting during heating This temperature was taken as the recycle temperature.

Example 1 1 part of TOTP was added to about 100 parts of AER260 for about 1 part.
The mixture was dissolved at 00 ° C., and 102 parts of Ultralite P were added and mixed (AER260 / Ultlite P = 1/1 (equivalent ratio)).

Since the obtained epoxy resin composition was liquid at room temperature, it could be used at room temperature.

The resulting epoxy resin composition was cast into a φ40 tin can, cured at 80 ° C. for 16 hours, and evaluated. Table 1 shows the results.

Example 2 To 100 parts of AER260, 23 parts (active ingredient) of piperazine dissolved in methanol were added and mixed.

Since the obtained epoxy resin composition was liquid at room temperature, it could be used at room temperature.

The obtained epoxy resin composition was cast into a tin can having a diameter of 40, and reacted at 60 ° C. while evaporating methanol.
Cured at 0 ° C. for 2 hours and evaluated. Table 1 shows the results.

Example 3 58 parts of EGTG and T for 100 parts of AER260
0.1 part of MAC was mixed at room temperature.

Since the obtained epoxy resin composition was liquid at room temperature, it could be used at room temperature.

The obtained epoxy resin composition was poured into a tin can having a diameter of 40 and then cured at 120 ° C. for 2 hours. Table 1 shows the results.

Example 4 0.5 part of TBZ was added to 6 parts of 100 parts of AER260.
After dissolving at 0 ° C., the mixture was cooled to room temperature, and then 102 parts of Ultralite P and 30 parts of KA8823 were added and mixed (AER260 / Ultrite P = 1/1 (equivalent ratio)).

Since the obtained epoxy resin composition was liquid at room temperature, it could be used at room temperature.

The resulting epoxy resin composition was cast into a φ40 tin can, cured at 60 ° C. for 16 hours, and evaluated. Table 1 shows the results.

Comparative Example 1 20 parts of HY956 was mixed with 100 parts of AER260.

Since the obtained epoxy resin composition was liquid at room temperature, it could be used at room temperature.

The obtained epoxy resin composition was cast in a tin can having a diameter of 40 tin, cured at room temperature for 16 hours, and evaluated. Table 1 shows the results.

[0056]

[Table 1]

Example 5 TOT was added to 90 parts of AER260 and 10 parts of XN1034.
After dissolving 1 part of P at about 100 ° C., the mixture was cooled to room temperature, and then 85 parts of talc and 135 parts of glass balloon were added and mixed until uniform with a kneader to obtain a putty-like composition (base material 1). .

Apart from the main agent 1, Ultralite P 100
Parts, 85 parts of talc, and 240 parts of a glass balloon were mixed by a kneader until uniform, to obtain a putty composition (curing agent 1).

The obtained main agent 1 and curing agent 1 were manually mixed at a weight ratio of 100: 100.

The obtained epoxy resin composition could be used at room temperature because of a putty that can be manually mixed at room temperature.

The obtained epoxy resin composition was placed on an aluminum plate so as to have a thickness of about 15 mm.
Cured for hours and evaluated. Table 2 shows the results.

Comparative Example 2 Main agent 1 was obtained in the same manner as in Example 5.

[0063] 50 parts of HY956, 85 parts of talc, and 30 parts of a glass balloon were mixed by a kneader until uniform, to obtain a putty composition (curing agent 2).

The obtained main agent 1 and curing agent 2 were manually mixed at a weight ratio of 100: 30. The obtained epoxy resin composition could be used at room temperature because of a putty that can be manually mixed at room temperature.

The obtained epoxy resin composition was applied on an aluminum plate to a thickness of about 15 mm, cured at room temperature for 16 hours, and evaluated. Table 2 shows the results.

[0066]

[Table 2]

[0067]

The composition of the present invention is a thermosetting resin composition which can be recycled by being softened and melted by heat like a thermoplastic resin while maintaining the workability of the thermosetting resin. In addition, the problem that it is difficult to recycle the thermosetting resin can be solved.

Continuing from the front page (72) Inventor Hirofumi Nishida 236 Nakai, Tatsuno-cho, Tatsuno-shi, Hyogo Nagasechem Tex Co., Ltd.Tatsuno Works F-term (reference) 4J002 BB032 BD032 CD041 CD051 CD061 CD081 CD111 CD131 CK022 EJ017 EJ027 EL026 EN027 EU137 EV017 FA082FD 4J036 AB01 AB15 AB20 AC01 AC05 AD07 AD08 AF06 AF15 AG06 AG07 AH07 AJ08 AJ21 DB06 DB11 DC03 DC05 DC06 DC39 DD02 FA01 FA05 FA06 FA11 FB02 FB07 FB10 JA12

Claims (4)

[Claims] 1. An epoxy resin (A) having an average number of functional groups of 1.5 to 2.2 and at least one of an amine compound, a phenol compound and a thiol compound having two functional groups capable of reacting with an epoxy group. A recyclable epoxy resin composition comprising one kind (B). 2. An epoxy resin (A) having an average number of functional groups of 1.5 to 2.2, at least one of an amine compound having two functional groups capable of reacting with an epoxy group, a phenol compound and a thiol compound. A recyclable epoxy resin composition comprising one type (B) and a thermoplastic resin (C). 3. The method according to claim 1, further comprising a filler (D).
Or the epoxy resin composition according to 2. 4. The epoxy resin composition according to claim 1, which is used for producing a master model or a jig.