JP2009121013A - Sizing agent for fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sizing agent for fiber which suppresses fuzz and thread breakage, exhibits a sufficient impact resistance when it is used for a fiber reinforced-resin. <P>SOLUTION: The sizing agent is an aqueous dispersion sizing agent used for fibers for a fiber reinforced-resin having mutually incompatible following (A) and (B). Herein, the (A) is an elastomer having a loss tangent at 25°C of 0.01 to 2 and a glass transition temperature of -150 to 25°C, and the (B) is an organic compound having a viscosity at 25°C of 10 to 20,000 mPa s and having a surface tension less than that of the component (A). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sizing agent used for fibers for fiber reinforced resins.

  It is known that when an impact is applied to a fiber reinforced resin, minute cracks generated around the reinforced fiber grow along the reinforced fiber and break. For this reason, attempts are made to suppress the growth of cracks and improve the impact resistance of the fiber reinforced resin by coating the surface of the reinforced fiber with a rubber-like substance capable of absorbing impact energy (Patent Documents 1 and 2). .

In addition, fibers for fiber reinforced resin are usually rubbed with metal pins or rollers for processing after the sizing agent is processed, but these fibers are more brittle than ordinary organic fibers, so fluff and thread breakage are not observed. Likely to happen. For this reason, an attempt has been made to suppress fluff and yarn breakage by covering the surface of the reinforcing fiber with a smooth epoxy resin or the like (Patent Document 3).
JP-A-7-26150 JP 2004-11030 A Patent No. 2957406

  Although the method proposed in Patent Document 1 or 2 is effective in improving the impact resistance of the fiber reinforced resin, the rubbery material has a high coefficient of friction, and thus fuzz and thread breakage occur during the processing step. There was a problem.

Moreover, although the method described in Patent Document 3 is effective in improving fluff and yarn breakage, it has a problem that the impact resistance of the fiber reinforced resin is not good because it cannot absorb impact energy.
An object of the present invention is to provide a fiber sizing agent that suppresses fuzz and thread breakage and has sufficient impact resistance when used in a fiber reinforced resin.

The present invention is a sizing agent in the form of an aqueous dispersion used for fibers for fiber reinforced resin in which the following (A) and (B), which are incompatible with each other, are dispersed in an aqueous medium.
(A): An elastomer having a loss tangent at 25 ° C. of 0.01 to 2 and a glass transition temperature of −150 to 25 ° C. or less.
(B): An organic compound having a surface tension less than the surface tension of (A) and a viscosity at 25 ° C. of 10 to 20,000 mPa · s.

  The fiber sizing agent of the present invention is excellent in smoothness during the fiber processing step, and can suppress fiber fluff and yarn breakage. Moreover, the fiber reinforced resin excellent in impact resistance is given.

In the sizing agent in the form of an aqueous medium dispersion of the present invention, an elastomer (A) and an organic compound (B) that are incompatible with each other are dispersed in an aqueous medium.
In the present invention, that (A) and (B) are not compatible with each other means that in the following test, it is non-uniform and two or more layers are formed.
(1) Collect 10 g of (A) and (B) into a glass bottle in terms of pure content and stir at room temperature for 10 minutes. When (A) and / or (B) is in the form of an aqueous dispersion, the aqueous medium is removed at a temperature of 80 ° C. and a reduced pressure of 10 mmHg for 3 hours.
(2) It is left to stand at 40 ° C. for 48 hours, and it is judged visually whether it is non-uniform and two or more layers are formed.

  In the above test, when (A) and (B) that do not form a non-uniform layer and do not form two or more layers are used as a sizing agent, both the impact energy absorbability and the smoothness are insufficient.

  Examples of the elastomer (A) include conjugated diene elastomers, acrylic resin elastomers, and urethane resin elastomers. These may be cross-linked. Moreover, you may use individually or in mixture of 2 or more types. Of these, urethane resin elastomers and conjugated diene elastomers are preferred from the viewpoint of adhesiveness to the reinforcing fibers and the matrix resin.

  Examples of the conjugated diene elastomer include polybutadiene, polyisoprene, polychloroprene, butadiene / styrene copolymer, butadiene / acrylonitrile copolymer, and the like.

  Examples of the acrylic resin elastomer include ethylene / propylene rubber and polyalkyl acrylate.

Examples of the urethane resin elastomer include elastomers composed of a polyisocyanate component (a1), a polyol component (a2), and other components (a3). Examples of the polyisocyanate component (a1) include the following polyisocyanates having 2 to 6 or more (preferably 2 to 3, particularly 2) isocyanate groups, and mixtures of two or more thereof.
(A11) Aliphatic polyisocyanate having 2 to 18 carbon atoms (excluding carbon in the isocyanate group, the same shall apply hereinafter):
Ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), heptamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, 2,2,4- or 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate Diisocyanates such as 2,6-diisocyanatomethylcaproate, 2,6-diisocyanatoethylcaproate, bis (2-isocyanatoethyl) fumarate and bis (2-isocyanatoethyl) carbonate; 1-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate and Gin ester triisocyanates (eg phosgenates of the reaction product of lysine with alkanolamines, 2-isocyanatoethyl-2,6-diisocyanatohexanoate and 2- or 3-isocyanatopropyl-2,6-di) Triisocyanate or higher polyisocyanate such as isocyanatohexanoate);

(A12) Aliphatic polyisocyanate having 4 to 15 carbon atoms:
Isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis (2-isocyanatoethyl) -4-cyclohexylene-1,2-dicarboxyl Rate and diisocyanates such as 2,5- or 2,6-norbornane diisocyanate; trifunctional or higher polyisocyanates such as bicycloheptane triisocyanate;
(A13) Aroaliphatic polyisocyanate having 8 to 15 carbon atoms:
m- or p-xylylene diisocyanate (XDI), diethylbenzene diisocyanate and α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI) and the like;
(A14) Aromatic polyisocyanate having 6 to 20 carbon atoms:
1,3- or 1,4-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate (TDI), 4, 4'- or 2,4'-diphenylmethane diisocyanate (MDI), m- and p- Isocyanatophenylsulfonyl isocyanate, 4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4,4′-diisocyanatodiphenylmethane and Diisocyanates such as 1,5-naphthylene diisocyanate; trifunctional or higher functional polyisocyanates such as crude TDI and crude MDI (polymethylene polyphenylene polyisocyanate);

(A15) Modified polyisocyanate:
Modified products of the above polyisocyanates, for example, modified products having carbodiimide, urethane, urea, isocyanurate, uretoimine, allophanate, biuret, oxazolidone and / or uretdione groups [modified products of urethane such as MDI, TDI, HDI and IPDI (polyol and Isocyanate-terminated urethane prepolymers obtained by reacting with excess polyisocyanate), biuret-modified products, isocyanurate-modified products, trihydrocarbyl phosphate-modified products, etc.] and mixtures thereof.

  Among these, preferred are (a12), (a13) and (a14) from the viewpoint of impact energy absorption, and more preferred are diisocyanates among (a13) and (a14).

  The polyol component (a2) is a number average molecular weight [hereinafter abbreviated as Mn. Mn is measured using gel permeation chromatography (GPC)] The high molecular polyol (a21) of 400 to 5,000, the low molecular polyol (a22) of less than Mn400 and the urethane resin elastomer are made hydrophilic. And a hydrophilic group-containing low molecular weight polyol (a23) for easy emulsification and a mixture of two or more thereof.

  Examples of the polymer polyol (a21) include polycarbonate diol, polyester diol, polyether diol, and a mixture of two or more thereof.

  As the polycarbonate diol, a conventional method, that is, a diol component (ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,8-octanediol and Obtained by reacting ethylene carbonate with ethylene carbonate alone or a mixture of two or more of 1,4-cyclohexanediol and the like, or by transesterification of the diol component with an aryl carbonate such as diphenyl carbonate. And the like.

  Specific examples of the polycarbonate diol include polycarbonate diols having a linear alkylene group having 4 to 10 carbon atoms (for example, polycarbonate diols of polytetramethylene carbonate diol, polypentamethylene carbonate diol, polyhexamethylene carbonate diol, and nonane diol). Polycarbonate diol having a branched alkylene group having 4 to 10 carbon atoms (for example, polycarbonate having a diol component of 2-methylbutanediol, 2-ethylbutanediol, neopentyl glycol, 2-methylpentanediol or 3-methylpentanediol) Diol) and mixtures of two or more thereof.

  As the polyester diol, a normal method, that is, a diol component (the same as described above) and a dicarboxylic acid component [aliphatic dicarboxylic acid (succinic acid, adipic acid, azelaic acid, sebacic acid, etc.), aromatic dicarboxylic acid (terephthalic acid, Or a mixture of two or more of isophthalic acid, phthalic acid, etc.], or a lactone (ε-caprolactone, γ-butyrolactone, γ-valerolactone, etc.) alone or 2 And the like obtained by a ring-opening polymerization of a mixture of at least species.

  As the polyether diol, an ordinary method, that is, an alkylene oxide (hereinafter abbreviated as AO) to the diol component exemplified above [ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO), 1 , 2-, 2,3- or 1,3-butylene oxide (hereinafter abbreviated as BO), tetrahydrofuran, styrene oxide, α-olefin oxide, epichlorohydrin, etc., or a mixture of two or more thereof] Or obtained by a method by carrying out in one step or multiple steps under normal pressure or under pressure in the presence of a catalyst (alkali catalyst, amine catalyst, acidic catalyst, etc.) (especially in the latter half of AO addition), etc. Is mentioned. In addition, the addition form in the case of using 2 or more types of AO may be a block or random.

  From the viewpoint of impact energy absorption, the polymer polyol (a21) is preferably a polyether diol, more preferably a polyether diol using one or more selected from the group consisting of EO, PO and BO. It is. The amount of (a21) used is usually 40 to 99%, preferably 60 to 95%, based on the total weight of (a2). In the above and the following, unless otherwise specified,% represents% by weight.

Examples of the low molecular polyol (a22) include polyhydric alcohols having 2 to 15 carbon atoms [dihydric alcohols (for example, ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol and diethylene glycol); For example, glycerin and trimethylolpropane); alkylene oxide (EO and / or PO) low molar adducts of these polyhydric alcohols (Mn less than 400) and the like].
The amount of (a22) used is usually 10% or less, preferably 8% or less, based on the total weight of (a2).

Examples of the hydrophilic group-containing low-molecular polyol (a23) for making the urethane resin elastomer hydrophilic so as to facilitate emulsification include, for example, carboxyl group-containing diols (2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolheptanoic acid, 2,2-dimethyloloctanoic acid and tartaric acid).
Of these, 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are preferred. The amount of (a23) used is usually 1 to 50%, preferably 2 to 20%, based on the total weight of (a2).

  Examples of (a3) include a compound (a31), a chain extender (a32) and a terminator (a33) used together with the polymer polyol (a21).

Examples of the compound (a31) used together with the polymer polyol (a21) include diamines having 2 to 10 carbon atoms (for example, ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, toluenediamine and piperazine), polyalkylenepolyamines ( For example, diethylenetriamine and triethylenetetramine), hydrazine or its derivatives (dibasic acid dihydrazide; such as adipic acid dihydrazide), amino alcohols having 2 to 10 carbon atoms (for example, ethanolamine, diethanolamine, 2-amino-2-methylpropanol and Ethanolamine), and carboxyl group-containing monoamines (glycine, alanine, valine, etc.) having the same effect as the above-mentioned hydrophilic group-containing low molecular polyol (a22), and Such carboxyl group-containing diamine (lysine and arginine, and the like).
The amount of (a31) used is usually 0.2 equivalents or less, preferably 0.1 equivalents or less, based on the equivalent of the isocyanate group of (a1).

Examples of the chain extender (a32) include diamines having 2 to 10 carbon atoms and amino alcohols having 2 to 10 carbon atoms mentioned in (a31). As the terminator (a33), monoalcohols having 1 to 8 carbon atoms (methanol, ethanol, isopropanol, cellosolves, carbitols, etc.), monoamines having 1 to 10 carbon atoms (monomethylamine, monoethylamine, monobutylamine) And mono- or dialkylamines such as dibutylamine and monooctylamine; mono- or dialkanolamines such as monoethanolamine, diethanolamine and diisopropanolamine). The total amount of (a32) and (a33) used is usually 0.8 equivalents or less, preferably 0.6 equivalents or less, based on the equivalents of the isocyanate groups in (a1).

  Moreover, when using the above-mentioned carboxyl group-containing monoamine or carboxyl group-containing diamine having the same effect as that of the above-mentioned hydrophilic group-containing low molecular polyol (a23) or (a23), the urethane resin elastomer is a hydrophilic group thereof. You may contain the basic compound which neutralizes (a carboxyl group etc.). Basic compounds include amines such as ammonia, alkylamines (such as trimethylamine, triethylamine and dipropylamine), alkanolamines (such as triethanolamine, diethanolamine and aminoethylpropanol) and alicyclic amines (such as morpholine)] and Examples include alkali metal (sodium, potassium, lithium, etc.) hydroxides. Among these, amines are preferable from the viewpoint of emulsion stability, and ammonia, triethylamine and aminoethylpropanol are more preferable.

  The urethane resin elastomer can be produced by a known method. For example, it can be obtained by a urethanization reaction using the raw material by a one-shot method or a multistage method. The reaction temperature for urethanization is usually 30 to 200 ° C, preferably 50 to 180 ° C. The reaction time is usually 0.1 to 30 hours, preferably 0.1 to 8 hours.

  The urethanization reaction is usually performed in a solventless system or in an organic solvent inert to the polyisocyanate. Examples of the organic solvent include acetone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, toluene, dioxane, and acetic acid ethyl ester.

  In the urethanization reaction, the ratio of the isocyanate equivalent in the polyisocyanate to the equivalent of active hydrogen groups contained in the polyol component (a2) (isocyanate equivalent / active hydrogen group equivalent) is usually 0.9 to 3, preferably 1.1 to 2, particularly preferably 1.2 to 1.6. The isocyanate group content in the polyurethane resin obtained by the urethanization reaction is usually 0 to 10%, preferably 0.5 to 10%.

  Moreover, when using the above-mentioned carboxyl group-containing monoamine or carboxyl group-containing diamine having the same effect as the above-mentioned hydrophilic group-containing low molecular polyol (a23) or (a23), these carboxyl groups were neutralized. Later, it may be dispersed in water. Thereafter, the chain can be extended with water and / or a chain extender (a32).

  The loss tangent of the elastomer (A) in the present invention at 25 ° C. is usually from 0.01 to 2, and preferably from 0.02 to 1. When the loss tangent is in the range of 0.01 to 2, the impact energy absorption is good and the impact resistance of the fiber reinforced resin is excellent. The loss tangent can be measured using a normal viscoelasticity tester.

  The glass transition temperature (Tg) of the elastomer (A) is usually −150 to 25 ° C., and preferably −150 to 0 ° C., more preferably −150 to −20 ° C. from the viewpoint of impact energy absorption. The glass transition temperature can be measured by the DSC method described in JIS K7121 (1987).

  Examples of the organic compound (B) include a compound (B1) having an epoxy group, a compound (B2) having an ester group, a polyol (B3), an oil component (B4), and a mixture of two or more thereof. Of the organic compound (B), the compound (B1) having an epoxy group is preferable from the viewpoint of the interfacial adhesion between the fiber and the matrix.

  As the compound (B1) having an epoxy group, two or more in one molecule such as diglycidyl ether (B11), diglycidyl ester (B12), diglycidylamine (B13) and alicyclic diepoxide (B14) The compound which has an epoxy group of this is mentioned. Examples of the diglycidyl ether (B11) include diglycidyl ether (B111) of dihydric phenol and diglycidyl ether (B112) of dihydric alcohol.

Examples of (B111) include condensates (including polycondensates) of divalent phenols having 6 to 30 carbon atoms and epichlorohydrin, both ends of which are diglycidyl ethers.
As the dihydric phenol, bisphenol (bisphenol F, bisphenol A, bisphenol B, bisphenol AD, bisphenol S, halogenated bisphenol A, etc.), catechin, resorcinol, hydroquinone, 1,5-dihydroxynaphthalene, dihydroxybiphenyl, octachloro-4, Examples include 4'-dihydroxybiphenyl, tetramethylbiphenyl, and 9,9'-bis (4-hydroxyphenyl) fluorene.

Examples of (B112) include condensates (including polycondensates) of diols having 2 to 100 carbon atoms and epichlorohydrin, both ends of which are diglycidyl ethers.
Examples of the dihydric alcohol include ethylene glycol, propylene glycol, tetramethylene glycol, 1,6-hexanediol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, neopentyl glycol, AO of bisphenol A (EO, PO and / or BO) (1 to 20 mol) adduct and the like.

Examples of the diglycidyl ester (B12) include an aromatic dicarboxylic acid diglycidyl ester (B121) having 8 to 20 carbon atoms and an aliphatic dicarboxylic acid diglycidyl ester (B122) having 2 to 20 carbon atoms.
Examples of (B121) include condensates (including polycondensates) of an aromatic dicarboxylic acid (B122) having 8 to 20 carbon atoms and epichlorohydrin, which have two glycidyl groups.
(B122) includes aromatic hydrogenated products of aromatic dicarboxylic acids having 8 to 20 carbon atoms (such as hexahydrophthalic acid and 4-cyclohexene-1,2-dicarboxylic acid) or aliphatic dicarboxylic acids having 2 to 20 carbon atoms. Examples include condensates (including polycondensates) of acid and epichlorohydrin, which have two glycidyl groups.

  The diglycidylamine (B13) is an N-glycidyl compound (N, G) obtained by a reaction of an aromatic amine having 6 to 20 carbon atoms and having 2 to 4 active hydrogen atoms (such as aniline and toluidine) and epichlorohydrin. N-diglycidyl aniline and N, N-diglycidyl toluidine).

  As the alicyclic diepoxide (B14), an alicyclic epoxide having 6 to 50 carbon atoms and 2 epoxy groups {vinylcyclohexene dioxide, limonene dioxide, dicyclopentadiene dioxide, bis (2,3-epoxy) Cyclopentyl) ether, ethylene glycol bisepoxy dicyclopentyl ether, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate and bis (3,4-epoxy-6-methylcyclohexylmethyl) butylamine}.

  Among these, from the viewpoint of smoothness, (B11) is preferable, and (B111) and (B112) are more preferable.

  Examples of the compound (B2) having an ester group include the following compounds and those described in JP-A-2006-97167.

(B21) monovalent ester compound;
For example, 2-ethylhexyl stearate, isodecyl stearate, isostearyl oleate, isoeicosyl stearate, isoeicosyl oleate, isotetracosyl oleate, isoarachidyl oleate, isostearyl palmitate, oleyl oleate, lauryl isostear Rate, lauric ester of lauryl alcohol EO 2 molar adduct and stearic acid ester of oleyl alcohol PO 2 molar adduct.
(B22) a divalent ester compound;
For example, glycerol dioleate, pentaerythritol tetraoleate, dioleyl adipate, diisotridecyl adipate, adipic acid diester of stearyl alcohol EO 10 mol adduct and dioleic acid ester of bisphenol EO 5 mol adduct.
(B23) a polyvalent ester compound;
For example, glycerol trioleate, sorbitol tetrastearate and trimellitic acid trilaurate.
(B24) Other esters;
For example, dilauryl thiodipropionate, dioleyl thiodipropionate and diisostearyl thiodipropionate.

  Among these (B2), the monovalent ester compound (B21) and the divalent ester compound (B22) are preferable from the viewpoint of fluffing.

  Examples of the polyol (B3) include the polyol component (a2). Among these, the polymer polyol (a21) is preferable from the viewpoint of the interfacial adhesion between the fiber and the matrix.

The following are mentioned as an oil-based component (B4).
(B41) Mineral oil; for example, refined spindle oil and liquid paraffin.
(B42) Animal and vegetable oils; for example, beef tallow, sperm whale oil, rapeseed oil, coconut oil and castor oil.
(B43) Silicone compound; for example, dimethylpolysiloxane, amino-modified silicone and phenyl-modified silicone.
(B44) natural and synthetic waxes; for example, carnauba wax, beeswax, paraffin wax and polyolefin wax [olefin having 2 to 18 carbon atoms, Mw = 1,000 to
10,000 waxes such as polyethylene wax]).

  Among these (B4), mineral oil (B41) and animal and vegetable oils (B42) are preferable from the viewpoint of fluffing.

  The surface tension of the organic compound (B) at 25 ° C. needs to be lower than the surface tension of the elastomer (A) at 25 ° C. When the surface tension of (B) is less than (A), a sizing agent having excellent surface smoothness is obtained. The reason for this is that (A) and (B) are not compatible with each other, so that (B) having a lower surface tension is likely to bleed out to the outermost layer on the fiber surface, resulting in excellent surface smoothness. Presumed to be fiber bundles. From the viewpoint of surface smoothness, the surface tension of the organic compound (B) is preferably 1 to 20 mN / m lower than (A).

In addition, surface tension is obtained by calculating | requiring the average value of 10 measurements at 25 degreeC by a hanging drop method using Kyowa Interface Science Co., Ltd. "full automatic interfacial tension meter PD-W". In addition, when the viscosity of the sample is 1000 mPa · s or more, the hanging drop method is not appropriate. Therefore, the critical surface tension is measured by the following method, and this is used instead of the surface tension.
(1) Ethanol and water are mixed at several volume mixing ratios of ethanol / water = 100/0 to 20/80 to prepare several kinds of mixed solutions.
(2) A sample is applied on a glass plate (for example, length 76 mm × width 26 mm × thickness 1 mm), and an aqueous medium or the like is removed by drying as necessary to form a dry film of the sample.
(3) The fully automatic interfacial tensiometer is set to the contact angle measurement mode, the liquid mixture prepared in (1) is dropped on the dry film of (2), the contact angle is measured 10 times at 25 ° C., and the average value is obtained. Ask for. By changing the ethanol / water ratio of (1), the surface tension is changed, and the surface tension of the mixed liquid of (1) in which the average value of the contact angle becomes 0 ° is obtained, and this is determined as the critical surface tension of the sample. And

  Moreover, the viscosity at 25 degreeC of an organic compound (B) is 10-20,000 mPa * s normally, Preferably it is 20-15,000 mPa * s from a smooth viewpoint. The viscosity here is measured by a Brookfield viscometer (BL type) in accordance with JIS K7117-1: 1999 (corresponding to ISO 2555: 1990). When the viscosity is less than 10 mPa · s, the converging property is insufficient, and when it exceeds 20,000 mPa · s, the smoothness is deteriorated, and thus fuzziness tends to occur.

  The weight ratio [(A) / (B)] of (A) and (B) is preferably 20/80 to 95/5, more preferably 50/50, from the viewpoint of smoothness and impact energy absorption. ~ 90/10.

Examples of the aqueous medium include known aqueous media (Japanese Patent Laid-Open No. 2006-124877). Two or more of these may be used in combination.
Among these, from the viewpoint of safety and the like, a mixed solvent of water and a hydrophilic organic solvent (acetone, dimethylformamide, dimethyl sulfoxide, methanol, ethanol and the like) is preferable, and water is more preferable.

From the viewpoint of cost and the like, a high-concentration dispersion is preferred during distribution, and a low-concentration dispersion is preferred during the production of fiber bundles. That is, by distributing as a high-concentration dispersion, the transportation cost and storage cost are reduced, and by diluting during fiber processing, the amount of adhesion to the fiber can be easily adjusted.
From the viewpoint of storage stability and the like, the content of the aqueous medium in the high-concentration dispersion is preferably 30 to 400%, more preferably 40 to 200%, based on the total weight of (A) and (B). It is.
On the other hand, the content of the aqueous medium in the low-concentration dispersion is 900 to 900 based on the total weight of (A) and (B), from the viewpoint of making the amount of sizing agent adhering to an appropriate amount when manufacturing the fiber bundle. It is preferably 100,000%, more preferably 1,300 to 20,000%.

Examples of the method for producing the sizing agent in the form of an aqueous medium dispersion of the present invention include the following methods.
(1): A method in which (A) and (B) are mixed in advance at 1 to 200 ° C., and then stirred and dispersed while being charged into an aqueous medium at 1 to 90 ° C.
(2): A method in which (A) and (B) are mixed in advance at 1 to 200 ° C., and then stirred and dispersed while introducing an aqueous medium at 1 to 90 ° C.
(3): A method in which (A) is produced in an aqueous medium by an emulsion polymerization method or the like, and then (B) is added and stirred and dispersed at 1 to 90 ° C.
(4): (A) and (B) are separately dispersed in an aqueous medium by the method of (1) or (2),
A method of mixing at 1 to 90 ° C.

When (A) and / or (B) is dispersed in an aqueous medium, a surfactant (C) can be used in combination for the purpose of improving dispersibility. In addition, the combined use of a surfactant can also be expected to improve the smoothness as a sizing agent and reduce fuzz.
As the surfactant (C), known surfactants such as nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants (JP 2006-124877 A, International Publication WO 2003/37964). Can be used. Two or more of these may be used in combination.

As the surfactant (C), in addition to those described in the above-mentioned known documents, polyhydric (2 to 8 valent) alcohols having 2 to 6 carbon atoms (ethylene glycol, propylene glycol, glycerin, pentaerythritol and AO adduct of sorbitan etc. [weight average molecular weight (hereinafter abbreviated as Mw) 500-100,000], sulfate ester salt (sodium salt) of AO adduct (Mw 500-5,000) of C10-20 alkylphenol , Potassium salts, ammonium salts, alkanolamine salts, etc.), sulfuric acid of AO adducts (Mw 500-5,000) of arylalkylphenols having 14 to 62 carbon atoms [styrenated phenol, styrenated cumylphenol, styrenated cresol, etc.] Examples include ester salts.
In the surfactant (C), AO includes EO alone or a combination of EO and PO and / or BO. When at least one of PO and BO is included, a random adduct, a block adduct, and a mixed adduct thereof are included.

  Of the surfactants (C), anionic surfactants, nonionic surfactants, and mixtures of anionic surfactants and nonionic surfactants are preferred, more preferably alkylphenol AO adducts and arylalkylphenol AO adducts. , Sulfate ester salts of alkylphenol AO adducts, sulfate ester salts of arylalkylphenol AO adducts and mixtures thereof, particularly preferably arylalkylphenol AO (EO and PO) adducts and arylalkylphenol AO (EO and PO) Adduct sulfate salts and mixtures thereof.

  When the surfactant (C) is contained, the content of the surfactant (C) is 1 to 30% based on the total weight of (A) and (B) from the viewpoint of dispersion stability and smoothness. Is more preferable, and 1 to 20% is more preferable.

  There is no limitation on the mixing apparatus used for production, stirring blades (blade shape: chi-shaped, three-stage paddle, etc.), nauter mixer, ribbon mixer, conical blender, mortar mixer, universal mixer (universal mixing mixer 5DM-L, Sanken Manufacturing Co., Ltd.) and Henschel mixers can be used.

The sizing agent of the present invention may contain a resin (D) other than (A) and (B). When other resin (D) is contained, the focusing property becomes better.
Examples of the other resin (D) include thermoplastic resins and thermosetting resins other than (A) and (B).

Examples of the thermoplastic resin include thermoplastic resins (polyethylene, polypropylene, polystyrene, polyurethane urea, polyester, polyamide and the like described in International Publication WO2003 / 09015, International Publication WO2004 / 067612, or Japanese Patent Application Laid-Open No. 2005-120282. Acrylic resin, etc.).
Examples of the thermosetting resin include those that do not satisfy the condition (B) among the compounds (B1) having an epoxy group described above, and (meth) acrylate-modified resins and unsaturated polyesters described in JP-A-2007-39868. Examples thereof include resins. In addition, (meth) acrylate means a methacrylate and an acrylate.

Other resins (D) are preferably polyurethane urea, polyamide, epoxy resin, (meth) acrylate modified resin and unsaturated polyester resin, and more preferably epoxy resin and unsaturated polyester resin from the viewpoint of the strength of the molded article.
When other resin (D) is contained, the content of (D) is based on the total weight of (A) and (B) from the viewpoint of molded product strength and fluffing when used for fiber reinforced resin. 1-50% is preferable, More preferably, it is 1-30%.

The sizing agent of the present invention may contain known additives (smoothing agents, preservatives, antioxidants and the like described in JP-A No. 2006-124877).
When it contains an additive, the content of the additive is preferably 0.01 to 10%, more preferably 0.1 to 5%, based on the total weight of (A) and (B).

  As fibers to which the sizing agent of the present invention can be applied, known fibers such as carbon fibers, aramid fibers, glass fibers, ceramic fibers, metal fibers, mineral fibers, rock fibers and slug fibers (International Publication WO2003 / 47830 pamphlet, etc.) From the viewpoint of the strength of the molded body, carbon fibers, aramid fibers and glass fibers are preferable, and carbon fibers are more preferable.

  The fiber bundle of the present invention is obtained as a fiber bundle in which at least one selected from the group consisting of these fibers is treated with the above sizing agent to bundle about 3000 to 30,000 fibers.

Examples of the fiber processing method using a sizing agent include a spray method or a dipping method.
The adhesion amount of (A) and (B) on the fiber is preferably 0.05 to 5%, more preferably 0.2 to 2.5%, based on the weight of the fiber. Within this range, the strength of the molded body is further improved.

  The fiber product is a fiber product obtained by processing the fiber bundle, and includes woven fabric, knitted fabric, non-woven fabric (felt, mat, paper, etc.), chopped fiber, milled fiber, and the like.

The composite intermediate consists of a fiber bundle or fiber product and a matrix resin. If necessary, a catalyst may be contained. When the catalyst is contained, the strength of the molded body is further improved.
Examples of the matrix resin include thermosetting resins and thermoplastic resins (such as those described in the pamphlet of International Publication No. WO2003 / 09015), preferably other resins (D), more preferably polyamide resins, epoxy resins, Unsaturated polyester resins and vinyl ester resins.
Examples of the catalyst include known curing agents for epoxy resins and curing accelerators (Japanese Patent Application Laid-Open No. 2005-213337 etc.).

The weight ratio of the matrix resin to the fiber bundle (matrix resin / fiber bundle) is preferably 10/90 to 90/10, more preferably 20/80 to 70/30, particularly preferably from the viewpoint of the strength of the molded body. 30/70 to 60/40.
When the catalyst is contained, the content of the catalyst is preferably 0.01 to 10%, more preferably 0.1 to 5%, and particularly preferably 1 to 3 with respect to the matrix resin from the viewpoint of the strength of the molded body and the like. %.

The composite intermediate is a fiber bundle or a fiber obtained by hot-melting (melting temperature: 60 to 150 ° C.) a matrix resin or a matrix resin diluted with a solvent (acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, ethyl acetate, etc.) It can be manufactured by impregnating the product. When a solvent is used, it is preferable to dry the composite intermediate at 50 to 200 ° C. for 0.1 to 3 hours to remove the solvent.

The molded body is obtained by separately introducing a fiber bundle or fiber product and a matrix resin into a mold and molding and / or curing, or molding and / or curing a composite intermediate.
When the matrix resin is a thermoplastic resin, it can be formed into a molded body by heat molding in a mold at 150 to 300 ° C. and solidifying at room temperature.
When the matrix resin is a thermosetting resin, it can be formed into a molded body by thermoforming at 50 to 250 ° C. in a mold and curing. Curing does not need to be completed, but it is preferable that the molded body is cured to such an extent that the shape can be maintained. After molding, it may be further heated to be completely cured. The method of thermoforming is not particularly limited. For example, a filament wiping molding method (a method of winding and thermoforming a rotating mandrel while applying tension), a press molding method (a method of laminating prepreg sheets and thermoforming), an autoclave And a method of injection molding by mixing a chopped fiber or a milled fiber with a matrix resin.

[Example]
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Hereinafter, unless otherwise indicated, parts indicate parts by weight.

[Test method]
The loss tangent of (A) was measured using a “viscoelasticity tester Model DDV-25FP” manufactured by Orientec Co., at an ambient temperature of 25 ° C. and a frequency of 10 Hz.

  The glass transition temperature of (A) was measured according to the DSC method described in JIS K7121 (1987) using a “differential scanning calorimeter Model RDC220” manufactured by Seiko Instruments Inc.

The surface tension of (A) was measured using the “full-automatic interfacial tension meter PD-W” manufactured by Kyowa Interface Science Co., Ltd., and the critical surface tension as shown below was measured and used instead of the surface tension.
(1) Ethanol and water are mixed at several volume mixing ratios of ethanol / water = 100/0 to 20/80 to prepare several kinds of mixed solutions.
(2) A sample is applied on a glass plate (for example, length 76 mm × width 26 mm × thickness 1 mm), and an aqueous medium or the like is removed by drying as necessary to form a dry film of the sample.
(3) The fully automatic interfacial tensiometer is set to the contact angle measurement mode, the liquid mixture prepared in (1) is dropped on the dry film of (2), the contact angle is measured 10 times at 25 ° C., and the average value is obtained. Ask for. By changing the ethanol / water ratio of (1), the surface tension is changed, and the surface tension of the mixed liquid of (1) in which the average value of the contact angle becomes 0 ° is obtained, and this is determined as the critical surface tension of the sample. And

  The surface tension of (B) was determined as the critical surface tension when the viscosity was 1000 mPa · s or more. When the pressure was 1000 mPa · s or less, an average value of 10 measurement values was obtained by the hanging drop method.

The viscosity of (B) was an average value measured twice under the following conditions.
Model: BL type viscometer (manufactured by Toki Sangyo Co., Ltd.)
Measurement temperature: 25 ° C
When the viscosity is 10 to 100 mPa · s: rotor No. 1, rotation speed 60 rpm
When the viscosity is 100 to 1000 mPa · s: rotor No. 2, rotation speed 30 rpm
When the viscosity is 1000 mPa · s or more: Rotor No. 3, rotation speed 6 rpm

The compatibility between (A) and (B) was measured by the following method.
(1) Collect 10 g of (A) and (B) in a glass bottle in terms of pure content and stir at room temperature for 10 minutes. When (A) and / or (B) is in the form of an aqueous dispersion, the aqueous medium is removed at a temperature of 80 ° C. and a reduced pressure of 10 mmHg for 3 hours.
(2) It is left to stand at 40 ° C. for 48 hours, and it is judged visually whether it is non-uniform and two or more layers are formed.

Fluff was measured under the following conditions.
Five chrome-plated stainless steel rods with a diameter of 2 mm were arranged in a zigzag manner so that the carbon fiber bundle (1) passed through the surface at a contact angle of 120 ° at 15 mm intervals. The carbon fiber bundle (1) was zigzag between the stainless bars, and a tension of 1 kg was applied. Immediately before the winding roll, the carbon fiber bundle (1) was sandwiched between two 10 cm × 10 cm urethane foams having a load of 1 kg and rubbed at a speed of 1 m / min for 5 minutes. During this time, the weight of the fluff adhered to the sponge was measured. The smaller the value, the better the fluff characteristics.

The Charpy impact strength was evaluated as follows.
A matrix resin prepared by aligning the carbon fiber bundle (1) in one direction and preparing a weight ratio of bisphenol A type diglycidyl ether (epoxy equivalent 190) / BF3 monoethylamine salt = 100/3 is heated to 50 ° C. Impregnate. At this time, the amount of the carbon fiber bundle (1) is adjusted so that the weight ratio of the matrix resin and the fiber bundle (1) [matrix resin / fiber bundle (1)] is 30/70. After impregnation, the fiber bundle is stacked so as to have a thickness of 2 mm, cured at 150 ° C. for 1 hour under pressure (0.49 MPa), and further cured at 140 ° C. for 4 hours under the same pressure. The cured product thus obtained was cut with a diamond cutter, and Charpy impact strength was measured according to JIS K7077 (1991) on a test piece having a thickness of 2 mm, a width of 10 mm, and a length of 80 mm. The larger the value, the better the impact resistance.

  In Examples and Comparative Examples, the following (A-1) to (A-3) were used as elastomers.

Production Example 1 [Synthesis of Urethane Resin Elastomer Water Dispersion (A-1)]
Add 200 parts of polypropylene glycol (Sanyo Kasei Kogyo "Newpol PP-2000", Mn about 2,000), 25 parts of dimethylolpropionic acid, 80 parts of isophorone diisocyanate, 0.2 parts of dibutyltin dilaurate, The reaction was performed for 7 hours. The mixture was neutralized by adding 21 parts of triethylamine. This prepolymer was added to 660 parts of water at 25 ° C. with stirring, and 4.5 parts of ethylenediamine was further added and reacted at 50 ° C. for 2 hours to obtain 990 parts of an aqueous urethane resin elastomer dispersion (A-1). It was. Table 1 shows the values of loss tangent, glass transition temperature and surface tension measured after drying (A-1) at 100 ° C. for 2 hours to remove moisture.

Production Example 2 [Synthesis of Urethane Resin Elastomer (A-2)]
200 parts of polytetramethylene glycol (Mitsubishi Chemical PTMG2000, Mn about 2,000), 10 parts of 1,4 butanediol, 38.6 parts of toluene diisocyanate and 0.2 part of dibutyltin laurate were added, Reacted for hours. 0.6 part of isopropanol was added here, and it was made to react at 50 degreeC for 2 hours, and the urethane resin elastomer (A-2) was obtained. Table 1 shows the measurement results of loss tangent, glass transition temperature and surface tension of (A-2).

As an aqueous dispersion (A-3) of SBR elastomer, SBR latex “Nalstar SR-113” (manufactured by Japan A & L Co., Ltd .: 48% pure) was used. Table 1 shows the measurement results of loss tangent, glass transition temperature and surface tension measured after drying (A-3) at 100 ° C. for 2 hours to remove moisture.

  NipolAR54 manufactured by Nippon Zeon Co., Ltd. was used as the acrylic elastomer (A-4). Table 1 shows the measurement results of loss tangent, glass transition temperature and surface tension of (A-4).

Production Example 3 [Synthesis of Urethane Resin Elastomer Water Dispersion (A-5)]
Add 400 parts of polypropylene glycol (“Sanix PP-4000” manufactured by Sanyo Chemical Industries, Ltd., Mn about 4,000), 25 parts of dimethylolpropionic acid, 80 parts of isophorone diisocyanate, 0.2 part of dibutyltin dilaurate, and at 90 ° C. The reaction was performed for 7 hours. The mixture was neutralized by adding 21 parts of triethylamine. This prepolymer was added to 1060 parts of water at 25 ° C. with stirring, and 4.5 parts of ethylenediamine was further added and reacted at 50 ° C. for 2 hours to obtain 1590 parts of an aqueous urethane resin elastomer dispersion (A-5). It was. Table 1 shows the values of loss tangent, glass transition temperature and surface tension measured after drying (A-5) at 100 ° C. for 2 hours to remove moisture.

Production Example 4 [Synthesis of Urethane Resin Elastomer Water Dispersion (A-6)]
Add 100 parts of polypropylene glycol (“SANNICS PP-1000” manufactured by Sanyo Chemical Industries, Ltd., about 1,000 Mn), 25 parts of dimethylolpropionic acid, 80 parts of isophorone diisocyanate, 0.2 part of dibutyltin dilaurate, and at 90 ° C. The reaction was performed for 7 hours. The mixture was neutralized by adding 21 parts of triethylamine. The prepolymer was added to 470 parts of water under stirring at 25 ° C., 4.5 parts of ethylenediamine was further added, and the mixture was reacted at 50 ° C. for 2 hours to obtain 700 parts of an aqueous urethane resin elastomer dispersion (A-6). It was. Table 1 shows the values of loss tangent, glass transition temperature and surface tension measured after drying (A-6) at 100 ° C. for 2 hours to remove moisture.

  The following (B-1) to (B-7) were used as the organic compound (B). Table 2 shows the measurement results of the viscosity and the surface tension. Moreover, the following were used as surfactant (C) and other resin (D).

(B-1): Bisphenol A type epoxy resin (Epicoat 828 manufactured by Japan Epoxy Resin Co., Ltd.)
(B-2): Polyethylene glycol diglycidyl ether (Epolite 400E manufactured by Kyoeisha Chemical Co., Ltd.)
(B-3): Polypropylene glycol diglycidyl ether (Epolite 400P manufactured by Kyoeisha Chemical Co., Ltd.)
(B-4): Bisphenol A PO adduct (New Pole BP-5P manufactured by Sanyo Chemical Industries)
(B-5): Polypropylene glycol (Newyoru PP-400 manufactured by Sanyo Chemical Industries, Ltd.) (B-6): Oleoleolate (B-7): Polyethylene glycol (PEG-400 manufactured by Sanyo Chemical Industries, Ltd.)
(C-1): Styrenated phenol PO and EO adduct (Soprophor 796 / P manufactured by Rhodia Nikka Co., Ltd.)
(D-1): Bisphenol A type epoxy resin (Epicoat 834 manufactured by Japan Epoxy Resin Co., Ltd.)

Example 1
Charge 80 parts of (A-1) into a container in terms of pure matter, add 20 parts of (B-1) at 25 ° C. with stirring, and mix for 60 minutes at 25 ° C. 100 parts of an aqueous dispersion (S-1) was obtained.
The compatibility of the used (A) and (B) was tested in advance, and the results are shown in Table 3.
The following Examples 2 to 9 were similarly tested for compatibility in advance and the results are shown in Table 3.
Example 2
A water dispersion (in the same manner as in Example 1 except that (B-3) is used instead of (B-1).
S-2) was obtained.

Example 3
60 parts of (A-1) in terms of pure content is charged into a container, and 20 parts of (B-3) and 20 parts of (D-1) are charged at an internal temperature of 25 ° C. with stirring, and 120 parts at 50 ° C. After mixing for 100 minutes, 100 parts of an aqueous dispersion (S-3) was obtained in terms of pure content.

Example 4
A water dispersion (in the same manner as in Example 1 except that the charged amount of (A-1) is 50 parts in terms of pure and (B-1) 50 parts is used instead of 20 parts (B-1). S-4) was obtained.

Example 5
An aqueous dispersion (S-5) was obtained in the same manner as in Example 1 except that (B-5) was used instead of (B-1).

Example 6
(A-2) 300 parts, (B-3) 100 parts and (C-1) 100 parts were charged into a universal mixer (“Universal Mixing Stirrer” manufactured by Sanei Seisakusho Co., Ltd.) and uniformly mixed at 70 ° C. for 30 minutes. did. In this, 500 parts of water was dripped over 6 hours, keeping the temperature in the system at 50 ° C. to obtain 1000 parts of an aqueous dispersion (S-6).

Example 7
An aqueous dispersion (S-7) was obtained in the same manner as in Example 6 except that (B-6) was used instead of (B-3).

Example 8
An aqueous dispersion (S-8) was obtained in the same manner as in Example 6 except that (B-4) was used instead of (B-3).

Example 9
An aqueous dispersion (S-9) was obtained in the same manner as in Example 1 except that (A-3) was used instead of (A-1) and (B-2) was used instead of (B-1). It was.

Example 10
An aqueous dispersion (S-10) was obtained in the same manner as in Example 6 except that (A-4) was used instead of (A-2) and (B-1) was used instead of (B-3). .

Example 11
An aqueous dispersion (S-11) was obtained in the same manner as in Example 4 except that (A-5) was used instead of (A-1).

Example 12
An aqueous dispersion (S-12) was obtained in the same manner as in Example 4 except that (A-6) was used instead of (A-1).

Example 13
An aqueous dispersion (S-13) was obtained in the same manner as in Example 1 except that the amount of (A-1) was changed to 20 parts in terms of pure content and the amount of (B-1) was changed to 80 parts. .

Example 14
An aqueous dispersion (S-14) was obtained in the same manner as in Example 4 except that the charge of (A-1) was changed to 90 parts in terms of pure and the charge of (B-3) was changed to 10 parts. It was.

Comparative Example 1
(B-1) 300 parts, (B-6) 50 parts and (C-1) 100 parts were charged into a universal mixer (“Universal Mixing Stirrer” manufactured by Sanei Seisakusho Co., Ltd.) and uniformly mixed at 70 ° C. for 30 minutes. did. In this, 550 parts of water was dripped over 6 hours, maintaining the temperature in a system at 50 degreeC, and 1000 parts of comparative water dispersions (H-1) were obtained.

Comparative Example 2
(A-1) was used as the comparative aqueous dispersion (H-2).

Comparative Example 3
A comparative aqueous dispersion (H-3) was obtained in the same manner as in Example 4 except that (B-7) was used instead of (B-3).

Using the aqueous dispersions (S-1) to (S-14) of Examples and the aqueous dispersions (H-1) to (H-3) of Comparative Examples as sizing agents, pure components in these sizing agents Carbon fiber bundles obtained by diluting with water so that the ratio is 1.5%, dipping carbon fibers (fineness 800 tex, number of filaments 12,000), impregnating the sizing agent, and drying with hot air at 150 ° C. for 3 minutes Table 4 shows the results of evaluating the fluff and Charpy impact strength of (1).
In addition, the adhesion amounts of (A) and (B) in the carbon fiber bundle (1) were both 1.5% based on the weight of the fiber.

  The glass fiber bundle, the carbon fiber bundle or the aramid fiber bundle obtained by processing with the fiber sizing agent of the present invention, and the fiber product obtained by processing the same are suitable for a high-strength fiber reinforced resin with less fuzz. is there. This fiber reinforced resin can be suitably used as various civil engineering / architectural materials, transport aircraft materials, sports equipment materials, power generator materials, and the like.

Claims (10)

A sizing agent in the form of an aqueous dispersion used for fibers for fiber reinforced resin in which the following (A) and (B), which are incompatible with each other, are dispersed in an aqueous medium.
(A): an elastomer having a loss tangent at 25 ° C. of 0.01 to 2 and a glass transition temperature of −150 to 25 ° C.
(B): An organic compound having a surface tension less than the surface tension of (A) and a viscosity at 25 ° C. of 10 to 20,000 mPa · s. The sizing agent according to claim 1, wherein (A) is a urethane resin elastomer.   The sizing agent according to claim 1 or 2, wherein (B) is an organic compound having an epoxy group.   The sizing agent according to any one of claims 1 to 3, wherein a weight ratio [(A) / (B)] of (A) and (B) is 20/80 to 95/5.   The sizing agent according to any one of claims 1 to 4, wherein the fiber for fiber reinforced resin is at least one selected from the group consisting of glass fiber, carbon fiber and aramid fiber.   The fiber bundle obtained by processing 1 or more types of fibers chosen from the group which consists of glass fiber, carbon fiber, and an aramid fiber with the sizing agent in any one of Claims 1-5.   A fiber product comprising the fiber bundle according to claim 6.   A composite intermediate comprising the fiber bundle according to claim 6 or the fiber product according to claim 7 and a resin.   A molded body formed by molding and / or curing the fiber bundle according to claim 6 or the fiber product according to claim 7 and a resin.   The molded object formed by shape | molding and / or hardening | curing the composite intermediate body of Claim 8.