JP3149882B2 - Modified epoxy resin emulsion and fiber sizing agent using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel emulsion of a polysulfide-modified epoxy resin. The present invention also relates to a fiber sizing agent comprising an emulsion of a polysulfide-modified epoxy resin.

[0002]

2. Description of the Related Art Epoxy resins have excellent physical properties.
It is used in a wide range of fields, such as the electrical and electronic industries, the civil and building industries, the aerospace and space industries, and the general industry. Above all, in the field of civil engineering and construction, attention is paid to adhesion and chemical resistance to base materials, which are characteristics of epoxy resins, and they are used for applications such as heavy corrosion-resistant paints and linings, fiber sizing agents and adhesives.
However, the epoxy resin has a disadvantage that, although the cured product is excellent in strength, it is poor in flexibility. for that reason,
For example, when it is used as a corrosion-resistant paint for concrete, it has a disadvantage that it cannot sufficiently follow cracks and cracks caused by expansion and contraction of the concrete due to temperature changes.

[0003] As a means for solving such a drawback,
It is known to use a method in which a flexible resin is blended with an epoxy resin, and to use a modified epoxy resin in which a flexible structural unit is introduced into the molecule of the epoxy resin. Examples of the latter include urethane-modified epoxy resins, polyethylene oxide-modified epoxy resins, and polysulfide-modified epoxy resins. For example, the polysulfide-modified epoxy resin "FLEP" developed by Toray Thiokol Co., Ltd. can provide flexibility without impairing the advantages of conventional epoxy resins, and also blocks water vapor and carbon dioxide gas. It has excellent properties and can further improve adhesion and chemical resistance.

[0004] By the way, epoxy resins have been used together with organic solvents and diluents in the same manner as other general resins. Recently, however, epoxy resins have been used, for example, in the form of emulsions from the viewpoints of workability, safety and environmental protection. There is a demand for an aqueous composition such as In fact, some epoxy resins are used in the form of emulsions, and their use is expanding to new applications such as binders for processing paper and cloth and sizing agents for glass fibers, in addition to conventional coatings and adhesives. Tied.

[0005]

However, as described above, the polysulfide-modified epoxy resin having excellent physical properties as described above has not been emulsified at present.

Accordingly, an object of the present invention is to provide an emulsion of a polysulfide-modified epoxy resin which has flexibility, and is excellent in safety at the time of on-site construction and environmental protection.

Another object of the present invention is to provide a fiber sizing agent comprising an emulsion of the above-mentioned polysulfide-modified epoxy resin.

[0008]

Means for Solving the Problems As a result of intensive studies in view of the above-mentioned object, the present inventors have found that a polysulfide-modified epoxy resin having a specific structure can be emulsified using an emulsifier containing a nonionic surfactant. Can be easily emulsified. The present inventors have also found that this emulsion of polysulfide-modified epoxy resin is suitable as a fiber sizing agent.
Based on the above, the present invention has been made.

That is, the modified epoxy resin emulsion of the present invention is a W / O (oil-in-water) type or O / W (water-in-oil) type modified epoxy resin emulsion, wherein (a) the following general formula:

Embedded image (Wherein R ₁ and R ₃ are organic groups, and R ₂ is an organic group containing a sulfur atom), and (b) an emulsifier containing a nonionic surfactant. It is characterized by containing.

[0010] The fiber sizing agent of the present invention is characterized by comprising the above modified epoxy resin emulsion.

Hereinafter, the present invention will be described in detail. In the present invention, the polysulfide-modified epoxy resin is obtained by an addition reaction of a suitable sulfur-containing polymer or oligomer with a general epoxy prepolymer. The sulfur-containing polymer or sulfur-containing oligomer used herein is a compound having an —S— bond, —SS—
It has various sulfur bonds such as a bond and a -SSS-bond, and has two or more functional groups in a molecule capable of reacting with an epoxy group such as an OH group, an NH ₂ group, an NRH group, and an SH group. . The epoxy prepolymer is synthesized by a condensation reaction between an aliphatic polyol or an aromatic polyol and epichlorohydrin and has two or more epoxy groups in a molecule. Preferably of the bisphenol type,
For example, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, halogenated bisphenol A-type epoxy resin, halogenated bisphenol F-type epoxy resin, and the like, or those having a molecular structure similar to these can be used.

The polysulfide-modified epoxy resin used in the present invention is an epoxy resin obtained by adding the above-mentioned epoxy prepolymer to a sulfur-containing polymer (or oligomer) in an amount of 2 equivalents or more, and reacting the same. It has a structure represented by the general formula. To describe the general formula in more detail, R ₂ is a residue derived from a sulfur-containing polymer (or oligomer), and examples thereof include the following.

-S (R ₄ S _m ) _n R ₅ S-, -O
_{(R 4 S m) n R} 5 O -, - S (R 4 S m) n R 5 N
_{(R 6) -, -S (} R 4 S m) n R 5 O -, - N
_{(R 6) (R 4 S} p) n R 5 N (R 6) -, - O (R 4
_{S p) n R 5 N (} R 6) -

Here, R ₄ and R ₅ are organic groups such as an alkylene group and an alkylene group containing an ether bond, and may have a substituent such as an OH group, an ether group, an ester group or a halogen group. They may be the same or different. R ₆ is hydrogen or an alkyl group having 1 to 5 carbon atoms. m is an integer from 0 to 5; n is an integer from 1 to 50;
It is an integer up to 5.

Specific examples of R ₄ and R ₅ are as follows (where a is 1 or more, preferably an integer of 1 to 50). _{- (CH 2) a -,} - (CH 2 OCH 2) a -, -
(CH ₂ CH (OH) CH ₂ ) _a −, − (CH ₂ C
H (CH ₃ )) _a -,-(CH ₂ CH ₂ OCH ₂ OCH
₂ CH ₂ ) _a −

Specific examples of R ₂ include those described above, and among these, those having —SS— (disulfide bond) are preferred, and particularly, —CH ₂ CH ₂ OCH ₂ OCH ₂ CH ₂ SS— What has as a structural unit is preferable.

Next, R ₁ and R ₃ are an epoxy prepolymer residue derived from an epoxy prepolymer, examples of which are as follows (where b is 1 or more, preferably an integer of 1 to 20): in and, R ₇ is -H or -CH _{3). - (OCH 2 CH 2) b} OCH 2 CH (OH) CH
_{2 -, - (OCH 2 CH} (CH 3)) b OCH 2 CH
(CH ₃₎ CH ₂ -,

Embedded image

Commercial names of such a polysulfide-modified epoxy resin include FL.RTM.
EP-10, FLEP-50, FLEP-60, FLE
P-80 and the like.

Nonionic surfactants used in the present invention include, for example, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, There are sorbitan monolaurate, sorbitan monostearate and the like, and those having an HLB value in the range of 8 to 18 are preferable. These nonionic surfactants are
They may be used alone or, in some cases, in combination of two or more.

In the present invention, a commonly used emulsification method for obtaining an emulsion can be used, but it is preferable to use a phase inversion emulsification method. That is,
First, a W / O emulsion is obtained by adding a small amount of water to the oil containing the surfactant and mixing. Next, the phase is inverted while gradually adding water to finally obtain an O / W emulsion. In this case, the oil component may be the polysulfide-modified epoxy resin alone or a mixture with another epoxy resin. In the case of a mixture with another epoxy resin, it is preferable that the above-mentioned polysulfide-modified epoxy resin is 10% by weight or more and the other epoxy resin is less than 90% by weight. Preferably, the resin is less than 70% by weight. Further, it may be used by dissolving it in an organic solvent in which the polysulfide-modified epoxy resin is soluble. Examples of the organic solvent that can be used include toluene, xylene, ethyl acetate, butyl acetate, methylene chloride, and chloroform. Apparatus used for mixing is suitably a shaft type stirrer having a rotating blade, a homogenizer, a homomixer, a colloid mill and the like. The emulsification temperature is 10 to 80
C. is desirable. It is more preferably in the range of 30 to 50 ° C.

The amount of the surfactant to be added is preferably 100 parts by weight or less, more preferably 100 parts by weight, based on 100 parts by weight of the polysulfide-modified epoxy resin (in the case of the polysulfide-modified epoxy resin and other epoxy resins, the total of both). Is about 10 to 20 parts by weight.

In order to obtain an emulsion having excellent stability, it is effective to add a water-miscible organic solvent which can dissolve the surfactant used. When such a water-miscible organic solvent is added, the surfactant can be efficiently dispersed in the oil, so that it is easy to form a W / O (oil-in-water) emulsion that is generated at the initial stage of phase inversion emulsification. . This W / O
The water dispersed in the emulsion has the effect of pulverizing the oil from the inside during the phase inversion achieved by adding more water, so that the particles of the O / W emulsion obtained are very poor. It becomes fine. As a result, it is considered that an emulsion having excellent stability is obtained.

Examples of the water-miscible organic solvent include monoalcohols such as methanol, ethanol and butanol.
Polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, and glycerin, acetone, dimethyl sulfoxide, N, N-dimethylformamide, tetrahydrofuran, dioxane, etc. It is. In the emulsification, these water-miscible organic solvents may be used alone, or in some cases, two or more thereof may be used in combination. When a water-miscible organic solvent is added, the amount added is one
The amount is preferably 100 parts by weight or less, more preferably 10 to 50 parts by weight, per 100 parts by weight.

[0024]

The present invention will be described in more detail with reference to the following examples. Example 1 100 parts by weight of a polysulfide-modified epoxy resin (FLEP-10 manufactured by Toraythiol Co., Ltd.) and a nonionic surfactant (Neugen EA-15 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
7: polyoxyethylene alkyl aryl ether) 5
20 parts by weight of water was added to the mixture, and the mixture was stirred and mixed at 5,000 rpm for about 3 minutes with a homogenizer to obtain a W / O emulsion. Subsequently, the addition and stirring of water were repeated until the total amount of the added water became 100 parts by weight. As a result, phase inversion occurred, and an O / W type polysulfide-modified epoxy resin emulsion was obtained. The appearance of the O / W emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 μm. After standing at room temperature for one week, it was recognized that a concentration difference occurred in the emulsion, but the emulsion could be returned to the initial state by stirring again.

Example 2 100 parts by weight of a polysulfide-modified epoxy resin (FLEP-10 manufactured by Toray Thiokol Co., Ltd.) and a nonionic surfactant (Neugen EA-15 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
7) 5 parts by weight and 40 parts by weight of xylene were mixed to obtain an O / W type polysulfide-modified epoxy resin emulsion in the same manner as in Example 1. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 µm. After standing at room temperature for one week, it was recognized that a concentration difference occurred in the emulsion, but the emulsion could be returned to the initial state by stirring again.

Example 3 100 parts by weight of a polysulfide-modified epoxy resin (FLEP-10 manufactured by Toraythiol Co., Ltd.) and a nonionic surfactant (Neugen EA-8 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
7, polyoxyethylene alkyl aryl ether) 5
The O / W-type polysulfide-modified epoxy resin emulsion was obtained in the same manner as in Example 1 by mixing parts by weight with 40 parts by weight of xylene. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 µm. After standing at room temperature for one week, it was recognized that a concentration difference occurred in the emulsion, but the emulsion could be returned to the initial state by stirring again.

Example 4 100 parts by weight of a polysulfide-modified epoxy resin (FLEP-10 manufactured by Toraythiol Co., Ltd.) and a nonionic surfactant (Neugen EA-15 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
7) 20 parts by weight and 10 parts by weight of ethylene glycol were mixed to obtain an O / W type polysulfide-modified epoxy resin emulsion in the same manner as in Example 1. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 0.3 to 0.8 µm. After standing at room temperature for one month, both the appearance and the average particle size remained in the initial state.

Example 5 100 parts by weight of a polysulfide-modified epoxy resin (FLEP-60 manufactured by Toray Thiokol Co., Ltd.) and a nonionic surfactant (Neugen EA-15 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
7) 20 parts by weight and 10 parts by weight of ethylene glycol were mixed to obtain an O / W type polysulfide-modified epoxy resin emulsion in the same manner as in Example 1. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 0.3 to 0.8 µm. After standing at room temperature for one month, both the appearance and the average particle size remained in the initial state.

Example 6 The polysulfide of Example 5 was used for the purpose of increasing the bonding property during spinning by bonding between glass fiber filaments and using as a protective film for preventing mechanical damage such as bending and bending after the spinning step. The modified epoxy resin emulsion was applied to the glass fiber surface and dried. Dozens of glass fibers coated with the polysulfide-modified epoxy resin emulsion were collectively formed into a cylindrical shape to obtain roving. The adhesion between the obtained glass fiber and the polysulfide-modified epoxy resin was good.

[0030]

By using a nonionic surfactant as an emulsifier for a polysulfide-modified epoxy resin emulsion, novel W / O and O / W emulsions of a polysulfide-modified epoxy resin can be easily obtained. In particular, by using a water-miscible organic solvent such as ethylene glycol together with a nonionic surfactant, a fine emulsion having excellent storage stability can be obtained.

The emulsion of such a flexible epoxy resin can be used not only as an anticorrosive paint and a coating agent, but also as a binder for processing paper, cloth and the like, and as a fiber sizing agent such as glass fiber. it can.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-186723 (JP, A) JP-A-3-157445 (JP, A) JP-A-50-19856 (JP, A) JP-A 54-1985 15956 (JP, A) JP-A-58-111831 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 63/00-63/10 C08G 59/30 C09J 163/00- 163/10 D06M 13/248

Claims (2)

(57) [Claims] (1) (a) The following general formula: (Wherein R ₁ and R ₃ are organic groups, and R ₂ is an organic group containing a sulfur atom), and (b) an emulsifier containing a nonionic surfactant. W / characterized by containing
O (oil-in-water) type or O / W (water-in-oil) type modified epoxy resin emulsion. 2. A fiber sizing agent comprising the modified epoxy resin emulsion according to claim 1.