KR20220007438A - Non-solvent hotmelt type vinylester based high speed curing resin composition and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a non-solvent hot-melt-type vinyl ester-based fast-setting resin and a method for manufacturing the same. Specifically, adding a polymerization inhibitor to an epoxy resin composition comprising a bisphenol A-based epoxy resin and a novolak-based epoxy resin; preparing a vinyl ester-based resin composition by adding an unsaturated monobasic acid and an amine-based catalyst mixture to the epoxy resin composition and adjusting the acid value to 25 or less; adding additives such as a coupling agent and a releasing agent to the vinyl ester-based resin composition; It relates to a method for producing a vinyl ester-based fast-curing resin composition, wherein an organic peroxy-based initiator is added to the vinyl ester-based resin composition to which the additive is added. According to the present invention, since there is no use of thickeners such as styrene monomer, reactive monomer dilution and magnesium oxide (MgO), which have volatile properties in high-performance fibers such as carbon fiber, glass fiber, and aramid fiber, harmful elements of volatile organic compounds (Volatile Organic Compund) To provide a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a viscosity and tacky that can be press-molded with excellent expression of properties, curing speed and room temperature storage stability at the same level as that of conventional epoxy resins. can

Description

Non-solvent hot-melt-type vinyl ester-based fast-curing resin composition and manufacturing method thereof

The present invention relates to a non-solvent hot-melt-type vinyl ester-based fast-setting resin and a method for preparing the same, and more particularly, to a bisphenol A-based epoxy resin and a no-block-based epoxy resin having various molecular weights and structures without the use of a volatile styrene monomer as a reactive diluent. A vinyl ester-based resin prepared by adding a polymerization inhibitor, an amine-based catalyst, and an unsaturated monobasic acid to an epoxy resin mixture containing it's about

In addition, the present invention relates to a non-solvent hot-melt-type vinyl ester-based fast-setting prepreg that can be press-molded using the non-solvent hot-melt-type vinyl ester-based fast-setting resin of the present invention.

Recently, the automobile industry is developing into a more convenient and eco-friendly industry through the subdivision of R&D, and as the development of new and renewable energy and green energy fields has recently become visible, vehicles such as hybrid vehicles, electric vehicles, and hydrogen vehicles that use new energy There is an increasing demand for weight reduction to improve fuel efficiency.

In addition, the automobile parts industry is paying attention to manufacturing automobile interior and exterior parts that can improve functionality and reduce costs. It is attracting attention as the only lightweight alternative to metal materials such as aluminum.

Carbon fiber-reinforced composite material (CFRP) is a method of impregnating an epoxy-based continuously curing resin as a matrix resin into carbon fiber, which is a reinforcing fiber. ) A technique for producing parts by compression molding with molding equipment is known.

Epoxy-based fast-setting resins, which are mainly used as matrix resins, have high strength and elastic modulus, but have problems in refrigerated storage due to their slow curing speed and poor storage stability at room temperature within 2 weeks. Compression molding of a sheet molding compound (SMC) material made by impregnating fibers with a liquid vinyl ester-based fast curing resin with a fast curing speed as a matrix resin is widely developed and applied.

Liquid vinyl ester-based fast-curing resin has the advantage of having a fast curing speed by radical reaction by using an organic peroxy-based initiator in a resin prepared by diluting volatile styrene monomer as a reactive monomer in vinyl ester resin. There is a safety problem of volatile organic compounds due to the use of substances.

Sheet molding compound (SMC) materials using vinyl ester-based resins have the advantage of being able to implement various and complex shapes at a lower price than prepregs, so they are being actively developed and applied. (SMC) material has limitations in its application as a structural material for automobile parts due to its low strength, modulus of elasticity and impact strength.

The present invention is to solve the above problems, and an object of the present invention relates to a non-solvent-type hot-melt-type vinyl ester-based fast-setting resin composition that can be press-molded and a method for manufacturing a prepreg using the same, and more specifically, to a mechanical Liquid vinyl ester or unsaturated polyester resins mainly used for epoxy-based fast-curing prepregs and matrix resins such as sheet molding compounds (SMC) and bulk molding compounds (BMC), which have excellent physical properties but have poor curing speed and room temperature storage stability In order to overcome the problems such as harmfulness to human body and environment, low impact strength, etc., a non-solvent hot-melt-type vinyl ester-based fast-curing resin with excellent fast curing time and room temperature storage stability while having mechanical properties similar to epoxy-based fast-setting prepregs and It is to provide the prepreg used.

According to an embodiment of the present invention for achieving the above object, a polymerization inhibitor, an amine-based catalyst, and an unsaturated monobasic acid are added to an epoxy resin mixture containing a bisphenol A-based epoxy resin and a novolak-based epoxy resin. A non-solvent hot-melt-type vinyl ester-based fast-curing resin composition comprising a vinyl ester-based resin and an organic peroxy initiator is provided.

According to an embodiment of the present invention, one or more additives selected from a coupling agent, a mold release agent, an antifoaming agent, a dispersion and phase separation inhibitor, and a reaction retarder are added to the vinyl ester-based fast-setting resin composition, a non-solvent hot-melt-type vinyl ester A continuously curing resin composition is provided.

According to one embodiment, the bisphenol A-based epoxy resin is included in the range of 50 to 80% by weight, the novolak-based epoxy resin is included in the range of 20 to 50% by weight, and the unsaturated monobasic acid is 0.9 to 1.15 with respect to the epoxy resin mixture A non-solvent hot-melt-type vinyl ester-based fast-curing resin composition is provided.

According to one embodiment, the acid value of the composition is 25 or less, the viscosity at 100 ℃ 10 to 50 poise, a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition is provided.

According to one embodiment, the bisphenol A-based epoxy (Diglycidyl ether of bisphenol A epoxy, DGEBA) has an equivalent weight of 180 to 200, 400 to 500, 600 to 700, 900 to 1,000 of epoxy resins of which 1 to 3 types are selected and , A non-solvent hot-melt-type vinyl ester-based fast-setting resin composition is provided, characterized in that it comprises one or two selected phenol novolac or cresol novolac epoxy having an equivalent weight of 170 to 220.

According to another embodiment, a first step of adding a polymerization inhibitor to an epoxy resin mixture comprising a bisphenol A-based epoxy resin and a novolak-based epoxy resin;

a second step of preparing a vinyl ester-based resin composition having a viscosity of 100°C in the range of 10 to 50 poise by adding an unsaturated monobasic acid and an amine-based catalyst to the epoxy resin mixture to adjust the acid value of the composition to 25 or less; and

There is provided a method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, comprising a third step of adding an additive and an organic peroxy-based initiator to the vinyl ester-based resin composition.

According to one embodiment, the method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that 50 to 80% by weight of the bisphenol A-based epoxy resin and 20 to 50% by weight of the novolak-based epoxy resin are mixed. this is provided

According to one embodiment, in the first step of adding the polymerization inhibitor, there is provided a method for producing a vinyl ester-based fast-curing resin composition, characterized in that the temperature inside the reactor is 100 to 115 ℃.

According to one embodiment, in the second step of adding the unsaturated monobasic acid and the amine-based catalyst, an unsaturated monobasic acid and an amine-based catalyst mixture are added while maintaining the temperature inside the reactor at 100 to 115° C. for 1 to 4 hours. Then, there is provided a method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that the acid value of the reactant is adjusted to 25 or less by stirring for 0.5 to 3 hours.

According to one embodiment, in the third step, the additive is selected from a coupling agent, an antifoaming agent, a mold release agent, a reaction retarder, and an agent for preventing dispersion and phase separation, and in the step of adding the additive, the reactor internal temperature is 85°C to 95°C. There is provided a method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that it is maintained.

According to one embodiment, in the step of adding the organic peroxy initiator, the method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that the internal temperature of the reactor is maintained at 70 ° C. to 85 ° C. provided

According to one embodiment, the non-solvent hot melt type vinyl ester fast curing resin composition prepared by adding the organic peroxy initiator has a viscosity of 10 to 45 poise at 100 ° C. There is provided a method for producing a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition, characterized in that the curing behavior starts at 100° C. or higher without it.

According to another embodiment, preparing the non-solvent hot-melt-type vinyl ester-based fast-setting resin composition in the form of a film using a roller heated to a temperature of 40 to 80 ℃;

preparing a hot-melt-type fast-curing prepreg by putting the film in a prepreg manufacturing impregnator adjusted to 90 to 130° C. and impregnating the reinforcing fibers;

Non-solvent hot-melt-type vinyl ester comprising the step of curing the fast-curing prepreg by at least 95% within 1 minute by applying a pressure of 0.1 to 10 MPa under a temperature of 120 to 170 ° C. upper mold and 120 to 170 ° C. lower mold in a mold A method for manufacturing a continuous curing resin prepreg is provided.

According to another embodiment, there is provided a non-solvent hot-melt-type vinyl ester-based fast-setting resin prepreg manufactured according to the manufacturing method.

The non-solvent hot-melt-type vinyl ester-based fast-setting resin composition of the present invention is volatile because there is no use of thickeners such as styrene monomer, reactive monomer dilution and magnesium oxide (MgO) having volatile properties in high-performance fibers such as carbon fiber, glass fiber, and aramid fiber. Non-solvent hot melt with no harmful elements of organic compounds (VOC) and with viscosity and tacky for press molding with excellent curing speed and room temperature storage while expressing the same level of physical properties as conventional epoxy resins It is possible to provide a vinyl ester-based fast-curing resin composition.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a non-solvent hot-melt-type vinyl ester-based fast-setting resin, a manufacturing method thereof, a prepreg containing the fast-setting resin, and a manufacturing method thereof, and an epoxy resin comprising a bisphenol A-based epoxy resin and a nobla-based epoxy resin adding a polymerization inhibitor to the mixture; adding an unsaturated monobasic acid and an amine-based catalyst mixture to prepare a vinyl ester-based resin having an acid value, viscosity, and tacky suitable for preparing a fast curing prepreg; adding an additive such as a coupling agent; A method for producing a non-solvent hot-melt type vinyl ester-based fast-setting resin composition that exhibits rapid curing at 130 to 160°C for 2 minutes or less by adding a medium or high-temperature curing agent, and 40 to 80°C Manufacturing in the form of a thin film using a roller heated to a temperature, putting the film in a prepreg manufacturing impregnator controlled at 90 to 130° C. Vinyl ester-based fast curing resin, characterized in that it further comprises the step of applying a pressure of 0.1 to 10 MPa to the prepreg in a mold at 120 to 170 ° C. and a lower mold at 120 to 170 ° C. to cure 95% or more within 1 minute. It is achieved by a method for producing a prepreg comprising a.

The vinyl ester-based resin is 20 to 80% by weight of bisphenol A (BPA) epoxy, 20 to 80% by weight of phenol novolak and cresol novolak epoxy, preferably 50 to 80% by weight of bisphenol A (BPA) epoxy, phenol novolac and a method of adding a polymerization inhibitor, an amine-based catalyst, and an unsaturated monobasic acid mixture gradually dropwise to an epoxy resin mixture in which 20 to 50% by weight of a cresol novolak-based epoxy is mixed. It is characterized in that it is a vinyl ester-based resin for preparing a prepreg whose viscosity and tackiness are controlled by a method of attaching and reacting methacrylic acid having a double bond to a ring-opened epoxy group.

When the bisphenol A-based (BPA) epoxy content is less than 20% by weight, it is difficult to control the viscosity as a hot-melt-type fast-setting resin, and it is difficult to prepare a fast-setting prepreg due to high tacky, and when it exceeds 80% by weight, the tacky is It tends to be low and has poor mechanical properties. In addition, when the content of phenol novolak and cresol novolak-based epoxy is less than 20% by weight, it is difficult to control tacky and the physical properties are poor.

In the resin mixture, the bisphenol A epoxy (Diglycidyl ether of bisphenol A epoxy, DGEBA) has an equivalent weight of 180 to 200 (eg, Kukdo Chemical YD-128), and an equivalent weight of 400 to 500 (eg, Kukdo Chemical, YD-011), equivalent of 600 to 700 (eg, Kukdo Chemical, YD-012), and equivalent of 900 to 1,000 (eg, Kukdo Chemical, YD-014) of 1 to 3 types of epoxy resins, equivalent It is a resin mixture in which one or two types of 170 to 220 phenol no-block type (eg, Kukdo Chemical, YDPN-638) or cresol no-block type epoxy (eg, Kukdo Chemical, YDCN-500) are mixed, and 100 to It may be sufficiently melted at 160° C. to have sufficient viscosity to react with an unsaturated monobasic acid such as methacrylic acid.

The vinyl ester-based resin is a polymerization inhibitor, an amine-based catalyst, and an unsaturated monobasic acid mixture is gradually added dropwise to the epoxy resin mixture to terminate the reaction when the acid value reaches about 25 or less, preferably in the range of about 3 to 15. , It is characterized in that the viscosity and tacky optimized for the preparation of hot melt prepregs are controlled by ring-opening the epoxy group attached to the terminal group of the epoxy resins, and attaching and reacting methacrylic acid having a double bond to the ring-opened epoxy group.

The polymerization inhibitor is at least one selected from hydroquinone toluhydroquinone, methylhydroquinone, para t-butylcatachol, phenolthiazine, chloranyl, and triphenylphosphine, and is 0.02 to 0.5 wt% based on the total epoxy resin It is used to prevent gelation of the resin due to the breakage of double bonds by heating during resin synthesis and to maintain resin storage or process stability of the resin. Since the polymerization inhibitor has a great effect on the initial reaction, when used in an amount of less than 0.02 wt%, non-uniform polymerization and gelation may occur during synthesis. When used in an amount of more than 0.5 wt%, color change and It may delay the curing time of the final fast-curing vinyl ester-based resin, resulting in poor workability. In addition, 0.05 to 0.15 wt% of triphenylantimony serving as a stabilizer for the resin may be used.

In the step of adding the polymerization inhibitor, the temperature inside the reactor is characterized in that 100 to 115 ℃. In this temperature range, the polymerization inhibitor in powder form can be quickly dissolved in the epoxy resin composition, and the reaction can be continuously induced by adding an unsaturated monobasic acid and an amine-based catalyst mixture within 10 minutes after adding the polymerization inhibitor. can The lower limit temperature may be up to 90°C, but is preferably 100°C for reaction temperature and continuity. When the temperature is less than 100 ° C, the polymerization inhibitor is in the form of a powder and is not sufficiently dissolved in the epoxy resin mixture. It is not manufactured.

The amine-based catalyst is at least one selected from triethylamine, ethyltrimethylamnonium bromide, dimethylbenzylamine, and di-n-butylamine, and may be used in an amount of 0.1 to 0.8 wt% based on the total epoxy resin. The amine catalyst serves to ring-open the epoxy group attached to the end of the epoxy resin so that unsaturated monobasic acids such as methacrylic acid are combined. When the content of the amine-based catalyst is less than 0.1% by weight, the reaction rate is slowed, resulting in a problem of color change due to oxidation and a low conversion rate to vinyl ester. Polymerization and gelation may occur.

The unsaturated monobasic acid includes methyl methacrylic acid, methacrylic acid, acrylic acid, etc. In general vinyl ester-based resins, methacrylic acid or methyl methacrylic acid is mainly used, and the amount used is 0.9 to 1.15 in an equivalent ratio to the epoxy resin. If the input equivalent ratio is less than 0.9, the conversion ratio of the epoxy groups attached to the end groups of the epoxy resin to the vinyl ester-based resin having a double bond is low, and the curability may be deteriorated by the remaining epoxy groups. If the input equivalent ratio exceeds 1.15, the reaction acid value is high , a problem of harm to the human body due to the generation of an acid odor during resin processing and a gelation reaction by residual acids may occur.

In the step of adding the unsaturated monobasic acid and the amine-based catalyst mixture, the temperature inside the reactor is maintained at 100 to 115° C. for 1.5 to 4 hours. After adding the unsaturated monobasic acid and the amine-based catalyst mixture, 1 to It is characterized by stirring for 3 hours.

As such, the present invention is a method of terminating the reaction when the acid value becomes 25 or less by maintaining the temperature inside the reactor in the range of 100 to 115° C. after the addition of the unsaturated monobasic acid to the epoxy resin mixture. The composite viscosity of the prepared resin is 10 to 50 poise at 100° C., preferably 15 to 45 poise, and most preferably 20 to 35 poise. If the viscosity is less than 10 poise, the flowability of the resin is high, so prepreg molding is not good. In addition, when the acid value is more than 25, the acid value is high, so there is a problem in that a problem of harm to the human body due to the generation of an acid odor during resin processing and a gelation reaction by residual acids may occur.

Then, in the step of adding the additive, additives such as a coupling agent, an agent for preventing dispersion and phase separation, an antifoaming agent, a releasing agent, and a reaction delaying agent are further added. The coupling agent is used to improve the interfacial adhesion between the resin and fibers, and is preferably 0.1 to 10% by weight. In particular, 1 to 5% by weight, more particularly 3 to 5% by weight, are preferred. As a specific example, BYK-C8013 (manufactured by BYK) may be used. When the content of the coupling agent is less than 0.1% by weight, the adhesion between the resin and the fiber interface is lowered, and there is a problem that a layer separation phenomenon occurs. It can be a problem.

The dispersion and phase separation inhibitor may also help improve interfacial adhesion between the resin and the fiber, like the coupling agent. Examples include 1-methoxy-2-propanol, n-butyl acetate, butylcellosolve, ethylcellosolve, isopropanol, isobutanol, rosin, It is at least one selected from derivatives of rosin, and is preferably used in an amount of 0.01 to 5% by weight. When used in less than 0.01 wt %, there is a problem in that the compound layer is separated. On the other hand, even if it is used in excess of 5% by weight, it is difficult to expect any further improvement effect, so that it is within the above range.

As the reaction delay agent, benzoquinone, tert-butylcatechol, etc. may be used alone or a mixture of the two may be used. The reaction retardant serves to delay the curing temperature to a certain temperature during molding and to enable curing in a short temperature range, and the content is preferably 0.5 to 5% by weight. If it is less than 0.5% by weight, there is a slight problem in the effect, and when used in excess of 5% by weight, there is a problem that the curing time is long.

The release agent is used for facilitating the release of the product from the mold during the molding of the product, and the release agent used in the present invention includes zinc stearate (Zn-Stearate), calcium stearate, and mixtures thereof. It is one or more selected, and 0.1 to 5% by weight may be used. When using less than 0.1% by weight, there is a problem in that it is difficult to demold the product after molding, and when used in excess of 5% by weight, adhesion performance with other products may be impaired.

The antifoaming agent serves to remove air bubbles present in the resin, and air is introduced during resin synthesis so that air bubbles are present in the reactant. When added to remove internal air bubbles. The content of the antifoaming agent is in the range of 0.5 to 5% by weight, and if the content is less than 0.5% by weight, it is difficult to exhibit sufficient antifoaming effect, and if it is more than 5% by weight, there may be a problem in that the strength of the composite material is lowered. Examples of the anti-foaming agent include, but are not limited to, aromatic-free polymeric anti-foaming agents, for example, BYK-1791 manufactured by BYK.

In the step of adding the additive, it is characterized in that the internal temperature of the reactor is maintained at 80 to 95 ℃. The reaction between the raw material of the epoxy resin and the unsaturated monobasic acid occurs actively at 100°C or higher, and when the temperature rises above 115°C, the reaction occurs rapidly and the desired result cannot be obtained. However, at 90° C., the reaction is weak or does not occur well, and additives must be added at the end of this reaction. Additives are those that play a role when press-molding into a fast-curing prepreg using the prepared resin. Among the additives, a reaction retarder and a coupling agent self-react at 113°C or higher, but even at 100°C lower than that. Partially, self-reaction may occur. Therefore, it is safest to set the safe temperature to 90±5℃.

The high temperature curing agent is tert-butyl peroxybenzoate (TBPB), di-(tert-butyl peroxy cyclohexane, DBPC), dichlorophenol (dichlorophenol, DCP), tert-amyl peroxybenzoate (TAPB), tert-butylperoxy 2-ethylhexyl carbonate (TBPEC) 2.5-dimethyl-2.5-di ( tert-butylperoxy)hexane (2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane, DMDBPH), tert-amylperoxy 20ethylhexyl carbonate (TAPEHC), at least one selected from the group consisting of tert-butyl peroxy-3,5,5-trimethyhexanoate (TBPTMH) and mixtures thereof, and the medium temperature curing agent is Benzoperoxide, dibutyl phthalate (DPB), dioctyl phthalate (DOP), trioctyl trimellatate (TOTM), tert-butyl peroxy-2-ethylhexanoate (t-butyl peroxy-2) -ethylhexanoate, TBPO) and characterized in that at least one selected from the group consisting of mixtures thereof, it is preferable to use an organic peroxy initiator as a high-temperature curing agent.

The high temperature curing agent is preferably contained in an amount of 0.05 to 3% by weight in the curing agent mixture of the present invention. When the high temperature curing agent is used in less than 0.05 wt%, the curing rate of the product is slow and there is a problem that mechanical properties are deteriorated after molding. there is

As a preferred example of the curing agent, the organic peroxy initiator is added while maintaining the internal temperature of the reactor at 70 to 85°C. When the temperature is less than 70 ℃, the viscosity of the resin composition is low and flowability is poor, so processing is difficult. When the temperature is more than 85 ℃, the initiator, which should show an initiating effect when molding a fast curing prepreg, reacts in the resin composition manufacturing step. have.

Preferred organoperoxy initiators are tert-butyl peroxybenzoate (TBPB), tert-butylperoxy 2-ethylhexyl carbonate (TBPEC), di-(t-butyl peroxycyclohexane) DBPC [di-(t-butyl peroxycyclohexane)], tert-amyl peroxybenzoate (TAPB), DMDBPH [2,5] -Dimethyl-2,5-di(tert-butylperoxy)hexane], tert-butyl peroxy-3,5,5-trimethyhexanoate (TBPTMH), tert-amylperoxy 20ethylhexyl carbonate (TAPEHC), and mixtures thereof more than one

The non-solvent hot-melt-type vinyl ester-based fast curing resin composition prepared by the addition of the organic peroxy initiator has a viscosity of 10 to 45 poise at 100 ° C. It is characterized in that the curing behavior begins.

The curing behavior should start above 110° C. because curing should not occur during the prepreg manufacturing process. That is, the synthesized resin is generally heated and melted at a temperature of about 60 to 80° C. to prepare a film for carbon fiber impregnation. In order to manufacture the film, the resin is completely melted in an oven at about 60~80℃ and then the film is manufactured through R/O. Hardening should not occur during melt/film manufacturing, and the film should be sufficiently melted when manufacturing the prepreg with the prepared film. In order to be impregnated with carbon fiber, the impregnation temperature should be between about 90~115℃. Therefore, it is preferable that the curing behavior starts above 110° C. because curing should not occur during the prepreg manufacturing process. Of course, there may be slight differences depending on the type of initiator.

The fast-setting resin composition may further include one or more additives such as a thermoplastic resin, a modified epoxy resin, and an elastomer resin.

Thermoplastic resins include polyvinyl formal, polyacrylate, phenoxy resin, polyamide, polyester, polyphenylene sulfide, polybenzimidazole, polyimide, polyetherimide, polysulfone, polyethersulfone, polyvinyl acetal. You can choose to use it, etc.

The modified epoxy resin may be selected from urethane-modified epoxy resin, dimer acid-modified epoxy resin, carboxyl-terminated butadiene acrylonitrile (CTBN), phenoxy resin, and the like.

As the elastomer resin, core-sell rubber (CSR), styrene-butadiene-methyl methacrylate copolymerization (SBM), methyl methacrylate-butylacrylate-methyl methacrylate copolymerization (MBM), styrene- butadiene, styrene-butadiene-methacrylic acid, butadiene-methacrylic acid, butadiene-methacrylic acid-calcium carbonate, alkyl styrene, acrylic acid-ester-methacrylic acid ester copolymer, and the like, and at least one type may be used.

The additives are preferably melted or dissolved in an epoxy resin, a raw material, when synthesizing the vinyl ester resin, and then used in an amount of 0.5 to 10 wt %, which is enough to not affect the reaction to the vinyl ester-based resin. These serve to improve toughness and impact resistance of the fiber-reinforced composite material together with a control role such as viscosity and tacky of the resin composition. When the additive is used in an amount of less than 0.5% by weight, the resin viscosity, adhesion, and the physical properties of the composite material are insignificant, and when used in an amount of more than 10% by weight, there is a problem in that the viscosity of the resin increases beyond the processable range. In general, even a small amount of high molecular weight polymer material has a great influence on the viscosity of the reaction composition. The modified epoxy resin and the elastomer resin cannot be added in an amount of 10 wt% or more. The reason is that the viscosity of the raw materials is too high, so a lot of bubbles are generated during the reaction, and the synthesis reaction cannot proceed because stirring is impossible. As a result of the present invention, PVF, which is a thermoplastic resin, cannot be used in an amount of 5 wt% or more.

Next, the prepreg manufacturing using the reinforcing fiber and the fast curing resin will be described. In the present invention, standard elastic H2550 (12K) carbon fiber produced by Hyosung Co., Ltd. was used as the reinforcing fiber, and the vinyl ester-based fast-setting resin prepared in the present invention was used as the matrix, and the non-solvent hot-melt type fast-setting resin was used as a film manufacturing coating machine. After manufacturing a film with a width of 1 m and a weight of 31 ± 1.0 g/m² using a roller at a temperature of 40 to 80 ° C using the device, the continuous fibers are laminated below and on the carbon fibers arranged in one direction to a temperature of 90 to 130 ° C. A prepreg having a carbon fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33% was prepared by passing it through a preheated impregnator.

There is no specific limitation or restriction on the type of reinforcing fibers used, and a wide variety of fibers including carbon fibers, glass fibers, graphite fibers, aramid fibers, boron fibers, alumina fibers and silicon carbide fibers can be used.

Further, there is no specific limitation or restriction on the form of the reinforcing fibers, including, for example, long fibers (stretched in one direction), tows, fabrics, mats, knits, braids, and short fibers (chopped to a length of less than 10 mm). Fibers having various shapes may be used.

There are various methods of manufacturing a prepreg by impregnating the matrix resin into the reinforcing fibers, but representative impregnation methods include a wet method and a hot melt (dry) method. The wet method is first performed by dissolving the matrix resin composition in a solvent such as styrene or methyl ethyl ketone. It is a method of impregnating the reinforcing fibers in the matrix resin composition by immersing the reinforcing fibers in a solution of the matrix resin composition produced by dissolving in methanol, acrylate, etc., recovering the solvent, and then completely removing the solvent through evaporation by an oven or the like.

In the hot melt method, the reinforcing fibers are directly impregnated with a matrix resin composition having fluid flow properties by preheating the resin composition, or first coated with a matrix resin composition on the surface of a release paper sheet for use as a resin film, and then the prepared film is formed into a flat shape. It can be carried out by arranging on one or both sides of the reinforcing fibers arranged as a , and then impregnating the resin film into the reinforcing fibers by applying heat and pressure. The hot melt method is the most used method because it does not use a solvent and has the advantage of being able to provide a prepreg with rapid productivity due to a simple process.

As a method for forming a fast curing prepreg prepared in the present invention, a press forming method in which a prepreg laminated to a predetermined thickness is seated in a lower mold preheated to 120 to 170° C. and compressed at a pressure of 0.1 to 10 MPa with an upper mold is the most effective. , the method is called a Prepreg Compression Molding (PCM) method and has an advantage in that the molding cycle time is 5 minutes or less and has a fast productivity. In addition, an autoclave molding method, a wrapping tape method, a bagging molding method, etc. may be suitably used.

The autoclave molding method is a method of manufacturing a product shape while laminating a prepreg on a mold plate of a certain shape, covering it with a bagging film, and then applying heat and pressure while drawing air from the laminated prepreg to harden it. This not only allows precise control of fiber orientation, but also has the advantage of providing a high-quality molding material with excellent mechanical properties due to the minimum void content, but has a disadvantage in that the molding time is 2 to 4 hours, resulting in lower productivity. Although there are differences depending on the resin and product characteristics, in general, the pressure applied during the molding process is 0.3 to 1.0 MPa, and the molding temperature is in the range of 90 to 200°C.

In the wrapping tape method, a prepreg is wrapped around a mandrel or rod, wrapped with a wrapping tape made of a thermoplastic film on a prepreg under tension for the purpose of fixing the prepreg, and cured by applying temperature and pressure inside an oven. It is a method of removing mandrels or rods, and is mainly applied when manufacturing tubular product materials. The molding pressure may be in the range of 0.1 to 2.0 MPa, the molding temperature may be in the range of 80 to 180° C., and the molding time may be in the range of 30 minutes to 1 hour.

The prepreg obtained by impregnating carbon fiber from the vinyl ester-based fast-setting resin according to the present invention is cured by a radical reaction generated during preheating to a certain temperature. Because of its excellent chemical properties, it can be said that it is particularly advantageous in fields that require rapid production speed and use in various environments. Representative fields may be automotive interior and exterior parts fields, general industrial applications, and may be advantageously used in sports/leisure applications, aerospace and space applications, and the like.

Hereinafter, specific examples are provided to help the understanding of the present invention. However, the following examples are only provided for easier understanding of the present invention, and the content of the present invention is not limited by the examples.

[Example 1]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 50 wt% of bisphenol A epoxy having equivalent weights of 180 to 190 and 400 to 500, respectively, and Noblak having an equivalent weight of 170 to 190 After adding 50% by weight of the resin, and starting stirring with gas injection, the temperature of the reactor was raised to 105° C. and completely melted, and then a polymerization inhibitor was added to keep the internal temperature of the reactor at 105° C. Thereafter, the methacrylic acid and amine-based catalyst mixture is slowly added dropwise through the dropping funnel at a rate not exceeding 115° C. for an internal temperature of 1.5 to 4 hours. After the dropping was completed, stirring was continued for 1 to 3 hours, and then the reaction was continued until the acid value became 5 to 25 while maintaining the internal temperature of the reactor at 115° C. or less to prepare a vinyl ester resin. When the acid value of the vinyl ester resin prepared by the reaction reaches between 5 and 25, the reactor temperature is lowered to 85 to 95 ° C., and then a coupling agent, a dispersion and phase separation inhibitor, an anti-foam agent, a release agent, a reaction delay agent, etc. are added. Dilute by stirring for 40 minutes. After the additive is completely dispersed and diluted in the vinyl ester-based resin, the temperature of the reactor is lowered to 75 to 85° C., a curing initiator is added, and dispersed and diluted for 20 to 40 minutes with stirring. A hot-melt-type vinyl ester-based fast-curing resin composition was prepared.

The prepared fast curing resin was put into a film coater preheated to 65 to 70° C. to prepare a thin film with a width of 1 m and a weight of 31 g/m². The manufactured film uses carbon fiber (H2550, 12K, Hyosung) with a tensile strength of 5.5 GPa and a tensile modulus of 250 GPa, and puts it into an impregnator for prepreg production. A continuously curing prepreg was prepared.

[Example 2]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 60 wt% of bisphenol A epoxy having equivalents of 180 to 190 and 400 to 500, respectively, and equivalents of 170 to 190 A non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a composite viscosity of 13 poise at 100° C. was prepared by adding 40 wt% of no-block resin to prepare a vinyl ester-based resin under the same conditions as in Example 1, and adding an additive and a curing agent did

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 3]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 70 wt% of bisphenol A epoxy having equivalent weights of 180 to 190 and 400 to 500, respectively, and Noblak having an equivalent weight of 170 to 190 30 wt% of the resin was added to prepare a vinyl ester-based resin under the same conditions as in Example 1, and an additive and a curing agent were added to prepare a non-solvent hot-melt-type vinyl ester-based fast curing resin composition having a composite viscosity of 18 poise at 100°C.

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 4]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 80 wt% of bisphenol A epoxy having equivalent weights of 180 to 190 and 400 to 500, respectively, and Noblak having an equivalent weight of 170 to 190 20 wt% of the resin was added to prepare a vinyl ester-based resin under the same conditions as in Example 1, and an additive and a curing agent were added to prepare a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a composite viscosity of 26 poise at 100°C. .

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 5]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., two types of bisphenol A epoxies with equivalent weights of 180 to 190 and 400 to 500, respectively 70 wt% and 170 to equivalent A non-solvent having a complex viscosity of 23 poise at 100°C by adding 15 wt% of a phenol novolak resin of 190, a cresol novolak resin having an equivalent weight of 190 to 220, manufacturing a vinyl ester-based resin under the same conditions as in Example 1, and adding an additive and a curing agent A hot-melt-type vinyl ester-based fast-curing resin composition was prepared.

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 6]

1.5 wt% of polyvinyl formal (PVF) is added to a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc. with equivalents of 180 to 190 and 400 to 500, respectively. 68.5% by weight of bisphenol A epoxy, 30% by weight of a novolak epoxy resin having an equivalent weight of 170 to 220, and after complete melting at 160°C for 4 to 6 hours, lowering the temperature to 105°C A non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a composite viscosity of 26 poise at 100° C. was prepared by preparing an ester-based resin and adding additives and curing agents.

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1 above. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuously curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 7]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 2.5 wt% of phenoxy resin is added with equivalents of 180 to 190 and 400 to 500, respectively, 2 types of Bisphenol A Epoxy 65 After adding to 30% by weight and 30% by weight of a novolak resin having an equivalent weight of 170 to 220, complete melting at 160° C. for 4 to 6 hours, lowering the temperature to 105° C., and manufacturing a vinyl ester-based resin under the same conditions as in Example 1 above And a curing agent was added to prepare a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a composite viscosity of 31 poise at 100°C.

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

[Example 8]

In a 5 liter synthesis reactor equipped with a stirrer, thermometer, air and nitrogen gas inlet pipe, gas outlet, cooling condenser, etc., 5 wt % of phenoxy resin is added with equivalents of 180 to 190 and 400 to 500, respectively, 2 types of Bisphenol A Epoxy 65 After adding to 30% by weight and 30% by weight of novolak resin having an equivalent weight of 170 to 220, completely melting at 160°C for 4 to 6 hours, lowering the temperature to 105°C, manufacturing a vinyl ester-based resin under the same conditions as in Example 1, and additives And a curing agent was added to prepare a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition having a composite viscosity of 45 poise at 100°C.

For the prepared fast-setting resin, a thin film having a width of 1 m and a weight of 31 g/m² was prepared under the same conditions as in Example 1. The prepared film was put into an impregnator for prepreg production under the same conditions as in Example 1 above to prepare a vinyl ester-based continuous curing prepreg having a fiber weight (FAW) of 125 g/m² and a resin content (RC) of 33%.

Table 1 is a table comparing the physical properties of the non-solvent hot-melt-type fast-setting resin composition and the prepreg prepared according to an embodiment of the present invention.

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Bisphenol A VE Resin (wt%) 50 60 70 80 70 68.5 68.5 65 Phenol Novolac VE Resin (wt%) 50 40 30 20 15 30 30 30 Cresol Novolac VE Resin (wt%) - - - - 15 - - - Phenoxy Resin (wt%) - - - - - - 2.5 5.0 PVF (wt%) - - - - - 1.5 - - TBPB (wt%) 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Resin viscosity at 100 ^o C (poise) 10 13 18 26 23 26 31 45 Storage stability (room temperature, months) 6 or more 6 or more 6 or more 6 or more 6 or more 6 or more 6 or more 6 or more Tacky height a little high fitness fitness fitness fitness fitness lowness 150 ^o C curing time (resin/prepreg) 1min 1min 1min 1min 1min 1min 1.5min 2min Tg(℃)(prepreg) 139 137 134 128 133 131 129 127 Tensile strength (MPa) (prepreg) 2,430 2,801 2,891 2,843 2,698 2,792 2,756 2,675 ILSS (MPa) (prepreg) 55 73 85 79 81 80 77 67

As shown in Table 1, a non-solvent hot-melt-type vinyl ester-based fast curing resin prepared by adding methacrylic acid after mixing 50 to 80% by weight of a bisphenol A-based epoxy resin and 20 to 50% by weight of a novolak-based epoxy resin, and manufactured using the same It was confirmed that one prepreg had a fast curing time of 2 minutes or less and a storage stability at room temperature of 6 months or more. On the other hand, conventional epoxy-based fast curing resins and prepregs (made by S company in Korea) have a ^{short curing time of about 3 minutes at 150 o} C and storage stability at room temperature of 2 weeks, so they are used while refrigerated.

As a result, the non-solvent hot-melt-type vinyl ester-based fast-curing resin composition of the present invention has excellent long-term storage stability of 6 months or more, and has a fast curing time of less than 2 minutes at a temperature of 150 ° C. This has an excellent effect.

In addition, the prepreg using the non-solvent hot-melt-type vinyl ester-based fast-setting resin composition of the present invention has the advantage of being able to realize the development of complex parts having complex shapes and thicknesses through a hybrid molding method with the general sheet molding compound (SMC) material being applied. In addition, when applied to automotive exterior parts, it is possible to provide a prepreg capable of reducing the weight by about 45% or more compared to the use of steel plate. In addition to automotive parts that require cost reduction through productivity improvement, applications such as industrial, sports/leisure, and aviation are possible.

The term "about" should be regarded as being omitted in front of the measured values such as temperature, concentration, and time published herein except in the examples, and the term "about" as used herein is subject to slight non-substantial deviations. It is meant to be within the scope of the teachings herein.

As mentioned above, although preferred embodiments of the present invention have been exemplified and described, the scope of the present invention is not limited thereto, and various modifications and improvements are possible based on the scope of the present invention defined in the claims below, and this is also belongs to the present invention.

Claims (13)

A non-solvent hot melt type comprising a vinyl ester compound synthesized by adding a polymerization inhibitor, an amine catalyst, and an unsaturated monobasic acid to an epoxy resin mixture containing a bisphenol A epoxy resin and a novolak epoxy resin, and an organic peroxy initiator As a vinyl ester-based fast curing resin composition,
The bisphenol A-based epoxy resin is included in the range of 50 to 80% by weight, the novolak-based epoxy resin is included in the range of 20 to 50% by weight, and the unsaturated monobasic acid is included in an equivalent ratio of 0.9 to 1.15 with respect to the epoxy resin mixture Phosphorus, non-solvent hot-melt-type vinyl ester-based fast curing resin composition. The non-solvent hot-melt-type vinyl ester-based fast-setting resin composition according to claim 1, further comprising at least one of a coupling agent, a mold release agent, an antifoaming agent, and a dispersion and phase separation preventing agent. According to claim 1, wherein the acid value of the composition is 25 or less, the viscosity at 100 ℃ 10 to 50 poise, a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition. The method of claim 1, wherein the bisphenol A-based epoxy (Diglycidyl ether of bisphenol A epoxy, DGEBA) resin has an equivalent weight of 180 to 200, an equivalent weight of 400 to 500, an equivalent weight of 600 to 700, an equivalent weight of 900 to 1,000 in the epoxy resin Non-solvent hot-melt-type vinyl ester-based, characterized in that it selects 1 to 3 types and selects 1 or 2 types of phenol novolac or cresol novolac epoxy resins having an equivalent weight of 170 to 220 A fast curing resin composition. A first step of adding a polymerization inhibitor to an epoxy resin mixture comprising a bisphenol A-based epoxy resin and a novolak-based epoxy resin;
a second step of preparing a vinyl ester-based resin composition exhibiting a viscosity of 100°C in a range of 10 to 50 poise by adding an unsaturated monobasic acid and an amine-based catalyst to the epoxy resin mixture to adjust the acid value of the composition to 25 or less; and
A third step of adding an additive and an organic peroxy initiator to the vinyl ester-based resin composition
A method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition comprising a. 6. The method of claim 5,
A method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that 50 to 80% by weight of a bisphenol A-based epoxy resin and 20 to 50% by weight of a novolak-based epoxy resin are mixed. 6. The method of claim 5,
In the first step of adding the polymerization inhibitor, the temperature inside the reactor is 100 to 115°C. 6. The method of claim 5,
In the second step of adding the unsaturated monobasic acid and the amine-based catalyst, 0.5 to 3 A method for producing a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition, characterized in that the acid value of the reactant is adjusted to 25 or less by stirring for a period of time. 6. The method of claim 5,
In the third step, the additive is selected from a coupling agent, an antifoaming agent, a mold release agent, a reaction retarder, and an agent for preventing dispersion and phase separation, and in the step of adding the additive, the reactor internal temperature is maintained at 85°C to 95°C , A method for producing a non-solvent hot-melt-type vinyl ester-based fast-curing resin composition. 6. The method of claim 5,
In the step of adding the organic peroxy initiator, the method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that the internal temperature of the reactor is maintained at 70 ℃ to 85 ℃. 6. The method of claim 5,
The non-solvent hot melt type vinyl ester fast curing resin composition prepared by adding the organic peroxy initiator has a viscosity of 10 to 45 poise at 100 ° C. A method for producing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition, characterized in that the behavior starts. Preparing a non-solvent hot-melt-type vinyl ester-based fast-setting resin composition prepared according to the manufacturing method according to claim 5 in the form of a film using a roller heated to a temperature of 40 to 80°C;
preparing a hot-melt-type fast-curing prepreg by putting the film in a prepreg manufacturing impregnator adjusted to 90° C. to 130° C. and impregnating the reinforcing fibers;
Curing the fast curing prepreg to 95% or more within 1 minute by applying a pressure of 0.1 to 10 MPa in a mold at a temperature of 120° C. to 170° C. upper mold and 120 to 170° C. lower mold temperature.
A method for producing a non-solvent hot-melt-type vinyl ester-based fast curing prepreg comprising a. A non-solvent hot-melt-type vinyl ester-based fast curing prepreg manufactured according to the manufacturing method according to claim 12.