JP3322990B2 - Resin composition for composite material and molding material containing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition for a composite material and a molding material containing the same. The resin composition for a composite material of the present invention is a molding material using various fiber base materials, for example, a sheet molding compound (hereinafter referred to as SM).
C), bulk molding compound (hereinafter abbreviated as BMC) or pultrusion method (pultruding method), filament winding method,
Hand lay-up method, spray-up method, resin injection method (resin injection method), resin transfer molding method (RT
M) and the like, and can also be used for the production of a sealing material containing a filler such as silica powder, and a general non-fiber-based molding material or composite material.

[0002]

2. Description of the Related Art Conventionally, a molding material using a thermosetting phenol resin as a matrix resin using various fibers as a reinforcing material, for example, SMC, BMC, etc., is generally manufactured using an alkali such as sodium hydroxide as a matrix resin as a matrix resin. Liquid resol type phenol resin is used.

However, when a liquid resol type phenol resin of this kind is used, a large amount of gas is generated at the time of molding to easily cause voids and swelling of the molded product, so that it is necessary to perform a complicated degassing operation at the time of molding. there were. In terms of quality, there is a problem that the molding shrinkage is large and the dimensional accuracy is inferior.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a first object of the present invention is to produce a void or a blister in a molded article without performing a degassing operation at the time of molding. It is an object of the present invention to provide a resin composition for a composite material which does not have the above. A second object is to provide a resin composition for a composite material that can obtain a molded product having a small molding shrinkage. Further, a third object is to provide a resin composition for a composite material in which odor at the time of molding is weak as in the conventional case.
Further, a fourth object is to provide a molding material containing a resin composition having such characteristics.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems of the prior art, and as a result, have found that a composite containing a specific liquid resol type phenol resin and a specific aliphatic carboxylic acid ester is used. The material resin composition was found to be extremely effective in achieving the above object, and the present invention was completed.

That is, the first aspect of the present invention is a liquid resol type phenol resin produced using a tertiary amine (preferably triethylamine) as a catalyst , triacetin and / or triacetin.
Or a resin composition for a composite material containing ethylene glycol diacetate (hereinafter simply referred to as a resin composition)
It is. A second invention is to further a molding material comprising said resin composition and fibers, and the third is a molding material comprising said resin composition, fiber, filler and thickener .

The liquid resol type phenol resin used in the resin composition according to the present invention functions as a curable matrix resin for binding and integrating components of a molding material or a composite material, such as fibers and fillers. Which can be prepared by reacting phenols with aldehydes in the presence of a tertiary amine (catalyst). In particular, the non-volatile content is 70 to 9
0% by weight, viscosity at 25 ° C. is 100 to 1000 mPa
A resin having an s and a number average molecular weight in the range of 180 to 300 is practically preferable. It should be noted that a silane coupling agent may be added to the liquid resol-type phenol resin for the purpose of further improving the adhesiveness between the fiber and the filler and the resin.

Preferred silane coupling agents include, for example, γ-aminopropyltriethoxysilane, N-β
Amino-based silanes such as (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Epoxy silanes, and mercapto silanes such as γ-mercaptopropyltrimethoxysilane. Such silane coupling agents may be used alone or in combination of two or more, and usually 0.1 to 3 with respect to the liquid resol type phenol resin.
%, Preferably in the range of 0.1 to 2% by weight.

The phenols include, for example, phenol, cresol, xylenol, nonylphenol,
Unsubstituted or substituted monohydric phenols such as para-tert-butylphenol, paracumylphenol and phenylphenol, resorcinol, alkylresorcinol,
Unsubstituted or substituted polyphenols such as catechol, hydroquinone, pyrogallol, and phloroglucinol, bisphenol A, bisphenol F, bisphenol S
And phenol-based purified residues such as bisphenol A, cresol residues, resorcinol residues, and bisphenol A residues.

The aldehydes include, for example, formaldehyde, paraformaldehyde, trioxane,
In addition to tetraoxane, polyacetal, glyoxal, furfural, acetaldehyde, butyraldehyde, crotonaldehyde, benzaldehyde, hydroxybenzaldehyde and the like can be mentioned.

When reacting them, they may be used alone or in combination of two or more. Further, the mixing ratio of the phenols (X) and the aldehydes (Y) is as follows:
The molar ratio (Y / X) is usually 1.0 to 2.5, preferably 1.1 to 1.6. If the compounding ratio is less than 1.0, the curability is poor, and if it exceeds 2.5, the amount of generated gas is increased, which is not preferable.

The tertiary amine used as a catalyst is an amine formed by replacing a hydrogen atom of ammonia with an alkyl group or an aryl group. Examples of such a tertiary amine include, for example, triethylamine, trimethylamine and trimethylamine. Propylamine, benzyldimethylamine, dimethylaniline, N-methylpiperidine and the like. Among them, triethylamine is particularly preferred in terms of catalytic activity and toxicity.

The amount of the tertiary amine is appropriately determined in consideration of its catalytic activity, but is generally 10% by weight or less, preferably 1 to 5% by weight, based on phenols. If necessary, the tertiary amine may be used in the form of other basic catalysts such as hydroxides, oxides and phosphates of alkali metals, and hydroxides of alkaline earth metals as long as the effects of the present invention are not impaired. And oxides, ammonia, alkanolamines and the like.

The aliphatic carboxylic acid ester used in combination with the liquid resol type phenol resin preferably functions to improve moldability and molding shrinkage, particularly moldability. the carboxylic acid esters such as methyl formate, ethyl formate, propyl formate, ethyl lactate, dimethyl succinate, dimethyl malonate, dimethyl sebacate, dimethyl oxalate, ethylene glycol monoacetate, ethylene glycol diacetic <br/> tape DOO , Mo Noasechin, diacetin, but like triacetin, even to allowed to more effectively achieve the object of the present invention in ethylene glycol diacetate and / or triacetin is not preferred. Also, from 1 to 30 the amount thereof relative to the liquid resol type phenolic resin
% By weight, preferably 1 to 10% by weight, more preferably 2% by weight.
~ 5% by weight. If the amount is less than 1% by weight, the object of the present invention cannot be achieved, and if it exceeds 30% by weight, further improvement in effect cannot be obtained, which is economically disadvantageous.

The fibers used for producing molding materials, composite materials, etc. (hereinafter simply referred to as molding materials, etc.) using the resin composition according to the present invention include, for example, natural fibers, synthetic fibers, recycled fibers, inorganic fibers, and the like. Examples thereof include fibers, metal fibers, functional fibers obtained by hollowing or surface-coating fibers, whiskers, and combinations of two or more of these. Specifically, wood flour, pulp, linter, waste cloth, recycled paper fiber, nylon fiber, polyvinyl alcohol fiber, acrylic fiber, polyethylene fiber, polypropylene fiber, polyester fiber, aramid fiber, polyester hollow fiber,
Copper-coated polyester fiber, phenol fiber, carbon fiber,
Glass fiber, rock wool fiber, silicon carbide fiber, alumina fiber, ceramic fiber, boron fiber, aluminum fiber, copper fiber, stainless steel fiber, potassium titanate whisker, calcium sulfate whisker and the like are exemplified.

The compounding amount of the fiber is appropriately determined according to the manufacturing method, application and required characteristics of the molding material, the fiber form, and the like. It is at least 5% by weight, preferably 10 to 50% by weight. In addition, these fibers are appropriately selected in any form depending on the use, for example, a filament, a strand, a chopped strand, a chopped strand mat, a continuum strand mat, a roving, a roving cloth, a strand cloth, a milled fiber, and a nonwoven fabric. Can be used.

Examples of the filler include calcium carbonate, barium sulfate, talc, clay, kaolin, silica powder, fine sand, diatomaceous earth, mica flake, gypsum, aluminum hydroxide, fly ash, graphite, powder rubber, and glass balloon. , Shirasu balloons, cured resin balloons, hollow balloons, and the like, but are not limited thereto. Such fillers may be used alone or in combination of two or more. The amount of the filler is determined as appropriate in consideration of the manufacturing method of the molding material, the use, the required characteristics and cost, the coatability of the resin composition, and the like. It is 10 to 200% by weight, preferably 50 to 150% by weight.

The thickener is a regulator for increasing the viscosity of the resin composition by aging to improve the moldability and handleability of the molding material. A preferable example having such properties is Alkali earth metal hydroxides or oxides are mentioned, and among them, magnesium oxide, magnesium hydroxide and a combination thereof are more preferable, and especially, the iodine adsorption amount is 10 to 50 mg / g, preferably 10 to 20 mg / g.
mg / g of magnesium oxide is preferred. The amount of the thickener is usually 1 to 1 with respect to the liquid resol type phenol resin.
0% by weight, preferably 2 to 5% by weight. If the iodine adsorption amount is 10 mg / g or the blending amount is less than 1% by weight, it takes a long time to adjust the viscosity of the molding material (the step of adjusting the moldability), or the desired viscosity cannot be attained. Is 50mg
If / g or the amount exceeds 10% by weight, not only is it difficult to control the viscosity, but also disadvantageously, storage stability deteriorates.

The resin composition according to the present invention may optionally contain a release agent in addition to the above components. Examples of the release agent include stearic acid, calcium stearate, zinc stearate, an aliphatic amide wax,
Carnauba wax, polypropylene wax and the like are used, and the amount of the wax is usually selected in the range of 0.5 to 5% by weight based on the liquid resol type phenol resin. Furthermore, other optional additives such as a viscosity modifier, a flame retardant, a plasticizer, and a coloring agent can be added in an appropriate amount.

The liquid resol type phenol resin , triacetin and / or ethylene glycol diacetate
The resin composition according to the present invention containing tate is used to produce various molding materials, sealing materials, composite materials, and the like by appropriately combining the above-described fibers, fillers, thickeners, and other additives. be able to. For example, a roving, mat, or fiber having any other form is singly or combined and continuously supplied to a resin composition tank (in some cases, individually, a resin tank and an aliphatic carboxylic acid ester tank) to form fibers. After impregnating the resin composition and adjusting the ratio of the resin composition and the fiber, the resin composition is drawn into a mold (die) having a predetermined molded product shape, heated and cured, and continuously or intermittently drawn and molded. In addition to manufacturing composite materials by the so-called pultrusion method (pultruding method), filament winding method, hand lay-up method, spray-up method, resin injection method (resin injection method),
The present invention can be applied to the production of a composite material by a resin transfer molding method (RTM) or the like.

Also, a resin composition, a filler, a thickener, and a release agent and other additives added as necessary to each of the mating surfaces of the two upper and lower polyethylene films moving in the same direction at a constant speed. A resin paste made of an agent is applied with a doctor blade or the like to form a resin paste layer.
Further, a predetermined amount of fibers is further sprayed or placed on the resin paste layer on the lower polyethylene film side to form a fiber layer. Then, after bonding the upper and lower polyethylene films so that the fiber layer is sandwiched by the resin paste layer,
The resin paste is impregnated with a roller or the like to impregnate the resin paste between the fiber layers and defoamed to form a sheet. Then, the obtained sheet is aged at room temperature to 60 ° C. to bring the resin paste into a desired state (formability or formability). The present invention can be applied to the production of so-called SMC in which the viscosity is increased up to (handling ability).

Further, after blending the same compound as SMC uniformly with a kneading machine such as a kneader, the fiber is added thereto and further kneaded to prepare a BMC precursor in which the fiber is uniformly dispersed, and this is mixed with the SMC. It can be applied to the production of a so-called BMC which undergoes aging treatment in the same manner as described above. Further, it can be used for the production of a sealing material containing a filler such as silica powder or a general non-fibrous molding material.

[0023]

EXAMPLES Next, the present invention will be described more specifically and in detail with reference to examples, but the present invention is not limited to these examples.

Production Example 1 1000 g of phenol, 880 g of a 47% by weight aqueous solution of formaldehyde, and 30 g of triethylamine as a catalyst were charged into a reaction vessel equipped with a stirrer, a reflux condenser and a thermometer and capable of reducing pressure. (1
(Around 00 ° C.) for 1 hour. Thereafter, the mixture was dehydrated and concentrated under a reduced pressure of 70 mmHg to prepare a liquid resol type phenol resin (A) having a nonvolatile content of 70% by weight. The obtained phenol resin (A) has a number average molecular weight of 230 and a viscosity of 20.
It was 0 mPa · s (25 ° C.). The nonvolatile content was measured by a heating loss method (180 ° C. × 40 minutes), the viscosity was measured by a B-type rotational viscometer, and the number average molecular weight was measured by HLC8 manufactured by Tosoh Corporation.
010 type gel filtration chromatography (separation column is G
XL1000 + 2000, eluent: tetrahydrofuran 1 ml / min, UV detector) to obtain a molecular weight distribution curve, which was determined by calibrating with a molecular weight calibration curve based on standard polystyrene.

Production Example 2 In the same manner as in Production Example 1, 1000 g of phenol was added to a reaction vessel.
After charging 880 g of a 7% by weight aqueous formaldehyde solution and 10 g of sodium hydroxide as a catalyst, the mixture was heated with stirring and reacted at a reflux temperature (around 100 ° C.) for 1 hour.
Thereafter, the mixture was cooled to 50 ° C., neutralized with paratoluenesulfonic acid, and then dehydrated and concentrated under a reduced pressure of 70 mmHg to prepare a liquid resol type phenol resin (B) having a nonvolatile content of 70% by weight. The obtained phenol resin (B) had a number average molecular weight of 240 and a viscosity of 300 mPa · s (25 ° C.).

Example 1 First, the phenolic resin (A) 1 prepared in Production Example 1 was used.
3 g of triacetin as an aliphatic carboxylic acid ester and 100 g of calcium carbonate as a filler
g, magnesium oxide as a thickener (iodine adsorption amount 20
mg / g) and zinc stearate (release agent) 3 g
And then mixed with a laboratory mixer to obtain a resin paste. Next, this was applied on a polyethylene film, and two sheets of glass chopped strands having a length of about 25 mm were scattered as fibers to prepare two sheets. Next, these sheets are laminated to form a sheet having a three-layer structure of polyethylene film / resin paste and glass fiber / polyethylene film, and then compressed by a roll to impregnate the glass chopped strand with the resin paste and defoam. Thus, an SMC precursor was obtained. The glass chopped strand was blended so as to be contained at 30% by weight in the SMC precursor (molding material). Then, the SMC precursor was aged at 40 ° C. for 60 hours to increase the viscosity, and the SMC having a viscosity of 6.3 × 10 ⁶ mPa · s (40 ° C.)
(I) was obtained. The weight per unit area of the obtained SMC (hereinafter abbreviated as “single weight”) was 3.0 kg / m ² .
The viscosity after the thickening treatment is a value measured by a B-type viscometer on a resin paste treated under the same conditions as the aging conditions of the SMC precursor.

Example 2 An SMC precursor was prepared in the same manner as in Example 1 except that ethylene glycol diacetate was used in place of triacetin. 0.4 × 10 ⁶ mPa · s (40 ° C.) and unit weight of 3.0
kg / m ² of SMC (II) was obtained.

Comparative Example 1 An SMC precursor was prepared in the same manner as in Example 1 except that triacetin was omitted.
Aging at ℃ gave SMC (III) having a viscosity of 6.8 × 10 ⁶ mPa · s (40 ° C.) and a unit weight of 3.0 kg / m ² .

Comparative Example 2 An SMC precursor was prepared in the same manner as in Example 1 except that the phenol resin (B) was used instead of the phenol resin (A), and this was aged at 40 ° C. The viscosity is 5.6 × 10 ⁶ mPa · s (40 ° C.) and the unit weight is 3.0 kg / m ²
SMC (IV) was obtained.

Comparative Example 3 An SMC precursor was prepared in the same manner as in Example 1 except that the phenol resin (B) was used instead of the phenol resin (A) and triacetin was omitted.
This is aged at 40 ° C. to have a viscosity of 5.6 × 10 ⁶ mPa · s.
At 40 ° C., an SMC (V) having a unit weight of 3.0 kg / m ² was obtained.

[Evaluation of SMC] The SMCs obtained in Examples 1 and 2 and Comparative Examples 1 to 3 were heated and pressed at a molding temperature of 150 ° C., a molding pressure of 9.8 × 10 ⁶ Pa, and a molding time of 180 seconds. A test specimen (length 30 cm × width 30 cm × thickness 3 mm) was prepared, and the state of generation of odor and gas during molding was examined. For the state of gas generation, a test specimen obtained by molding without degassing at the time of molding was visually evaluated, and a specimen having a void or swelling was evaluated as defective, and a specimen without swelling was evaluated as good. . The measurement of the molding shrinkage is JIS
-I went according to K-6911. At this time, the test pieces of Examples 1 and 2 were formed without degassing, and the test pieces of Comparative Examples 1 to 3 were formed by degassing at the time of forming so as not to cause voids and swelling. The results are shown in Table 1.

[0032]

[Table 1]

As is clear from Table 1, the SMC obtained by using the resin composition according to the present invention can obtain a molded product without voids and blisters without degassing at the time of molding like the conventional SMC. It was also confirmed that the molding shrinkage ratio was small. In addition, Example 1 shows that these effects can be achieved only based on a combination of a liquid resol type phenol resin produced using triethylamine as a catalyst and triacetin (aliphatic carboxylic acid ester).
And Comparative Example 2 were confirmed. In addition, S of the present invention
It was also confirmed that MC had an odor at the time of molding, which was as weak as conventional SMC.

[0034]

According to the resin composition for a composite material according to the present invention, it is possible to provide a good molded product which does not cause voids or swelling even without degassing as in the prior art.
Further, it is possible to provide a molded product having a molding shrinkage smaller than that of the prior art. Further, various effects such as the odor at the time of molding being reduced to a level not inferior to the prior art are exhibited. Also,
The molding material obtained by using the composition of the present invention having such an effect, particularly the molding material, can contribute to the improvement of productivity by simplifying the molding operation without contaminating the working environment, and can further reduce the molding shrinkage. Because we can provide small molded products,
It is useful in the molding field where strict dimensional accuracy is required, and its industrial value is extremely high.

Continuation of the front page (51) Int.Cl. ⁷ identification code FI C08K 7/02 C08K 7/02 (56) References JP-A-50-84690 (JP, A) JP-A-49-16793 (JP, A) JP-A-4-249543 (JP, A) JP-A-4-320442 (JP, A) JP-A-7-138450 (JP, A) JP-A-7-178507 (JP, A) JP-A-5-23788 (JP, A) JP-A-6-179040 (JP, A) JP-A-61-168574 (JP, A) JP-A-58-154433 (JP, A) JP-A-57-186 (JP, A) JP-A-6-239948 (JP, A) JP-A-53-94565 (JP, A) Holzforschung, 48 [2] (1994), p. 150-156J. Appl. Polym. Sc i. , 49 [12] (1993), p. 2157− 2170 (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 61/04-61/16 C08G 8/00-8/38 C08J 5/04-5/10 C08J 5/24 B29B 11 / 16 B29B 15/08-15/14 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. A liquid resol-type phenol resin produced using a tertiary amine as a catalyst , triacetin and / or
A resin composition for a composite material comprising ethylene glycol diacetate . 2. The resin composition according to claim 1, wherein the tertiary amine is triethylamine. 3. A molding material comprising the resin composition according to claim 1 or 2 and fibers. 4. A molding material comprising the resin composition according to claim 1 or 2 , a fiber, a filler and a thickener.