JPS5939387B2 - Adhesive for glass fiber bundling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a glass fiber binding adhesive that is a main ingredient of a glass fiber binding agent used to bundle glass filaments when producing glass fiber strands, and more specifically, The present invention relates to an adhesive for binding glass fibers that exhibits excellent performance in both the binding properties of glass filaments and the impregnating properties of the molding plastic impregnated therein.

Molded products made from glass fiber and unsaturated polyester, i.e. reinforced thermosetting plastics (FRP), have excellent properties such as strength and chemical stability, so they are used in bathtubs,
It is used in large quantities in a wide range of applications, including septic tanks, boats, automobile parts, containers, pipes, and hard hats.

Glass fibers are bundled by a binding agent during the manufacturing process when hundreds of filaments are brought together to form a strand. This sizing agent interferes with the impregnation of matrix resin such as unsaturated polyester resin between filaments and adhesion with glass when manufacturing reinforced plastics, and adversely affects the strength and transparency of reinforced plastics. In order to improve these properties, it is desirable to remove the sizing agent, but if the sizing agent is not sifted, the strands become untied during glass fiber production and reinforced plastic molding, reducing workability, which poses a problem. For these reasons, a sizing agent for glass fibers is required to have the ability to bond filaments together well and to be well impregnated with and compatible with a matrix resin such as an unsaturated polyester resin.

Conventionally, polyvinyl acetate resin emulsion has been mainly used as this type of focusing adhesive.

However, polyvinyl acetate resin emulsions have had the contradictory problem of poor impregnation and affinity for the unsaturated polyester resin when improving the focusing power, and poor focusing power when improving the impregnating power. In other words, when a polyvinyl acetate emulsion obtained by emulsion polymerization using a polymeric protective colloid such as polyvinyl alcohol or hydroxyethyl cellulose is used as the main ingredient, the glass filament has excellent focusing properties, but the matrix resin does not adhere to the focused glass fibers. The impregnating properties of FRP are significantly inferior, and the resulting FRP has poor strength and transparency.

In addition, when polyvinyl acetate emulsion emulsion polymerized using a surfactant is used as the main ingredient, the impregnating property of the matrix resin is excellent, but the focusing property is significantly inferior.
The strands become fluffy, which reduces workability and gives a good F.
I can't get RP. The present inventors have conducted intensive research focusing on the point that in order to solve this preliminary problem, it is only necessary to increase the focusing power without impairing the excellent impregnating properties of surfactant-based emulsions. However,
The present invention was completed based on the knowledge that the above problem can be solved by introducing a specific functional group into a vinyl ester monomer such as vinyl acetate. That is, the present invention provides (
a) vinyl ester monomer and (b) one or more selected from dialkylaminoalkyl unsaturated acids, vinylpyridine, and vinylcarbazole are emulsion polymerized in the presence of a nonionic surfactant. This is an adhesive for FRP glass fiber binding made of a copolymer emulsion.

The sizing agent based on the adhesive of the present invention has excellent focusing power because the copolymer emulsion, which is the adhesive of the present invention, contains one selected from dialkylaminoalkyl unsaturated acids and vinyl carbazole. Or it is because it contains two or more types of monomers. This means that monomers other than dialkylaminoalkyl unsaturated acids, vinylpyridine, and vinylcarbazole, such as carboxyl group-containing monomers, hydroxyl group-containing monomers, and glycidyl group-containing monomers, are excellent. This is clear from the fact that no focusing power can be obtained.

Any surfactant may be used to emulsion copolymerize one or more monomers selected from dialkylaminoalkyl unsaturated acids, vinylpyridine, and vinylcarbazole with vinyl ester monomers. This does not mean that only nonionic surfactants are effective.

Those using an anionic surfactant or a cationic surfactant have the disadvantage of poor focusing and impregnating properties. The sizing property of a glass fiber sizing agent is primarily related to the adhesion between the sizing adhesive, which is its main component, and glass, and the impregnation property is primarily related to the compatibility between the sizing adhesive and the styrene monomer. correlated with each other.

There is no need to explain the focusing property, but to explain the impregnating property, the unsaturated polyester commonly used as a matrix resin contains a large amount of styrene monomer as a crosslinking agent and a solvent.

Therefore, if the binding adhesive is insoluble in the styrene monomer, the resin will not be able to penetrate into the fine details of the glass fibers, and the FRP will become opaque. If the binding adhesive is soluble in the styrene monomer, it not only penetrates into the fine details of the glass fibers, but also cures in the polyester together with the styrene monomer, creating a transparent and strong FRP.
It will grow. Therefore, in order to evaluate the sizing properties and impregnation properties of a glass fiber sizing agent, it is sufficient to examine the adhesion of the main sizing adhesive to glass and the compatibility with styrene.

Another important thing is that glass fiber sizing agents mainly consist of a sizing adhesive, a surface treatment agent (coupling agent) that serves as a bridge between the glass and matrix resin, and a lubricant. They must be compatible with each other.

The copolymer emulsion which is the focusing adhesive of the present invention is
It also has excellent cationic miscibility stability, so it can be safely mixed with surface treatment agents and lubricants even if they are cationic.

Vinyl ester monomers used in the present invention include vinyl acetate, vinyl butyrate, vinyl propionate,
Fatty acid vinyl esters such as vinyl versatate (vinyl ester of a carboxylic acid having 10 carbon atoms and branched at the α-1 position; trade name manufactured by Ciel Corporation) are used.

Particularly preferred is vinyl acetate. It can also be used in combination with vinyl ester monomers and monomers such as ethylene and styrene copolymerized therewith. One type selected from dialkylaminoalkyl unsaturated acids, vinyl pyridine, and vinyl carbazole used in the present invention. or 2
Examples of the monomers include unsaturated dialkylaminoalkyl such as dimethylaminoethyl acrylate and dimethylaminoethyl methacrylate; vinylpyridine; vinylpyrrolidone, vinylcarbazole, and derivatives thereof.

The amount of one or more monomers selected from dialkylaminoalkyl unsaturated acids, vinylpyridine, and vinylcarbazole is 0.5 to 20% by weight based on the total monomers.
, preferably 0.5 to 10% by weight.

The nonionic surfactant used in the present invention is not particularly limited, but includes, for example, polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan alkyl ester, polyoxyethylene alkylamine, polyoxyethylene Examples include alkyl amide, polyoxyethylene polyoxypropylene, and the like.

The nonionic surfactant to be used preferably has an HLB value of 14 or more in view of its performance as an emulsifier in emulsion polymerization and its plastic impregnation properties as an adhesive for binding glass fibers.

The copolymer emulsion, which is the glass fiber binding adhesive of the present invention, contains one or more monomers selected from the vinyl ester monomer, the dialkylaminoalkyl unsaturated acid, vinylpyridine, and vinylcarbazole. It can be obtained by emulsion polymerization of the above-mentioned nonionic surfactant.

As the emulsion polymerization method, conventional methods can be used.

For example, either boiling point polymerization or low-temperature polymerization may be used, and monomer dropwise polymerization is particularly preferred. The polymerization initiator used for emulsion polymerization is not particularly limited, but peroxides conventionally used in emulsion polymerization such as hydrogen peroxide, potassium persulfate, ammonium persulfate, and t-butyl hydroperoxide; , 2-azobis(2-amidinopropane) and the like can be used.

Further, a peroxide and a reducing agent may be used together. The molecular weight of the copolymer in the copolymer emulsion affects the impregnability of the sizing agent. In other words, the lower the molecular weight, the better the solubility of the styrene monomer, and the better the impregnating properties. Therefore, if it is necessary to further improve the impregnating property, an effective means is to lower the molecular weight of the copolymer. As a method to lower the molecular weight,
During emulsion polymerization, a chain transfer agent such as aldehyde, mercaptan, or carbon tetrachloride may be used to adjust the degree of polymerization and lower the molecular weight. When the molecular weight is 100,000, it has a better effect on the impregnating properties of the glass fiber sizing agent. To prepare glass fiber sizing agents using the adhesives of the present invention, for example, methacrylate chromichloride,
vinyltriethoxysilane, vinyltrichlorosilane,
Vinyltri(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, r-aminopropyltriethoxysilane, γ-chloropropylmethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β
- A surface treatment agent such as -(3,4-epoxycyclohexino(c)ethyltrimethoxysilane), a lubricant such as a fatty acid amide compound, and the adhesive of the present invention may be uniformly mixed.

Furthermore, if necessary, plasticizers, antifreeze agents, preservatives, etc. conventionally used in general polymer emulsions may be added as appropriate.

Next, the adhesive of the present invention will be explained with reference to Examples and Comparative Examples.

Example 1 An aqueous solution prepared by dissolving 5 parts by weight of polyoxyethylene polyoxypropylene with an HLB of 15 in 93 parts by weight of ion-exchanged water was charged into a polymerization container equipped with a stirrer, a reflux condenser, and a charging port, and the air in the polymerization container was The internal temperature was raised to 68 to 70°C while replacing with nitrogen gas.

Separately, prepare 100 parts by weight of a mixed monomer consisting of 95 parts by weight of vinyl acetate and 5 parts by weight of dimethylaminoethyl metatarylate, put 10 parts by weight of it into a polymerization container, and add 2.2 L of azobis (2-amidino propane) 0.3
An aqueous catalyst solution was prepared by dissolving parts by weight in 12 parts by weight of ion-exchanged water, and 3 parts by weight of the aqueous catalyst solution was added to initiate polymerization.

30 minutes after the start of polymerization, the remainder of the mixed monomers and the remainder of the aqueous catalyst solution were added dropwise over 4 hours to carry out polymerization, and after the addition was completed, the mixture was further aged at 80°C for 1 hour to form a glass made of copolymer emulsion. I got an adhesive for fiber bundling. The obtained adhesive for binding glass fibers had a solid content concentration of 50% by weight, a viscosity of 400 cP, and a molecular weight of 100,000. Example
2 Example 2 An aqueous solution prepared by dissolving 5 parts by weight of polyoxyethylene alkyl ether with an HLB of 15 in 93 parts by weight of ion-exchanged water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, and a charging port, and 0.5 parts by weight of acetaldehyde was added. 6 parts by weight, and while replacing the air in the polymerization container with nitrogen gas,
The temperature was raised to 8-70°C.

Separately, prepare 100 parts by weight of a mixed monomer consisting of 97 parts by weight of vinyl acetate and 3 parts by weight of dimethylaminoethyl methacrylate, put 10 parts by weight of it into a polymerization container, and add 2,2-diazobis(2-amidinopropane). An aqueous catalyst solution in which 0.3 parts by weight was dissolved in 12 parts by weight of ion-exchanged water was prepared, and 3 parts by weight of the aqueous catalyst solution was added to initiate polymerization.

30 minutes after the start of polymerization, the remainder of the mixed monomers and the remainder of the aqueous catalyst solution were added dropwise over 4 hours to carry out polymerization, and after the addition was completed, the mixture was further aged at 80°C for 1 hour to form a glass made of copolymer emulsion. I got an adhesive for fiber bundling. The obtained adhesive for binding glass fibers had a solid content concentration of 50% by weight, a viscosity of 200 CP, and a molecular weight of 30,000.

Example 3 An autoclave equipped with a stirrer was charged with an aqueous solution in which 5 parts by weight of polyoxyethylene alkyl ether having an HLB of 15 and 0.3 parts by weight of acetaldehyde were dissolved in 120 parts by weight of ion-exchanged water.

After replacing the air outside the autoclave with ethylene, 100 parts by weight of vinyl acetate and 3.7 parts by weight of dimethylaminoethyl metatarylate were added, and 3 parts by weight of ethylene was added while stirring.
Polymerization was carried out by press-fitting until the pressure reached 0 Kf/C7l. 0.3 parts by weight of potassium persulfate was used as a polymerization catalyst, and the polymerization temperature was about 70°C. The polymerization reaction was carried out for about 7 hours, and after the reaction was completed, the mixture was cooled to release excess ethylene, thereby obtaining a glass fiber binding adhesive consisting of a copolymer emulsion. The resulting copolymer had an ethylene content of 15% by weight, a vinyl acetate content of 82% by weight, and a dimethylaminoethyl methacrylate content of 3% by weight.

The obtained adhesive for binding glass fibers had a solid content concentration of 50% by weight, a viscosity of 1,000 cP, and a molecular weight of 30,000. Example 4 An aqueous solution prepared by dissolving 5 parts by weight of polyoxyethylene nonyl phenyl ether with an HLB of 18 in 93 parts by weight of ion-exchanged water was charged into a polymerization container equipped with a stirrer, a reflux condenser, and a charging port, and the air in the polymerization container was The temperature of the inner abyss was raised to 70 to 72° C. while replacing the gas with nitrogen gas.

Separately, prepare 100 parts by weight of a mixed monomer consisting of 95 parts by weight of vinyl acetate and 5 parts by weight of vinylpyridine, put 10 parts by weight of it into a polymerization container, and further add 0.3 parts by weight of potassium persulfate through ion exchange. An aqueous catalyst solution dissolved in 12 parts by weight of water was prepared, and 3 parts by weight of the aqueous catalyst solution was added to initiate polymerization.

30 minutes after the start of polymerization, the remainder of the mixed monomers and the remainder of the aqueous catalyst solution were added dropwise over 4 hours to carry out polymerization, and after the dropwise polymerization was completed, the mixture was further aged at 80°C for 1 hour to form a copolymer emulsion. I got an adhesive for glass fiber bundling. The obtained glass fiber binding adhesive had a solid content concentration of 50% by weight,
The viscosity was 400 cP and the molecular weight was 100,000. Example 5 A polymerization vessel equipped with a stirrer, a reflux condenser, and a charging port was
Polyoxyethylene lauryl ether 5 with HLB of 18
An aqueous solution in which parts by weight were dissolved in 93 parts by weight of ion-exchanged water was charged, and the internal temperature was raised to 70 to 72° C. while replacing the air in the polymerization container with nitrogen gas.

Separately, prepare 100 parts by weight of a mixed monomer consisting of 98 parts by weight of vinyl acetate and 2 parts by weight of vinyl carbazole, put 10 parts by weight of that into a polymerization container, and add 0.2 parts by weight of ammonium persulfate to ion-exchanged water. An aqueous solution of catalyst dissolved in 12 parts by weight was prepared, and 3 parts by weight of the aqueous catalyst solution was added to initiate polymerization.

30 minutes after the start of polymerization, the remainder of the mixed monomers and the remainder of the aqueous catalyst solution were added dropwise over 5 hours to carry out polymerization, and after the dropwise polymerization was completed, it was further aged at 80°C for 1 hour to form a copolymer emulsion. A glass fiber concentrated adhesive consisting of

The obtained adhesive for binding glass fibers had a solid content concentration of 50% by weight, a viscosity of 1000 cP, and a molecular weight of 80,000.

Comparative Example 1 A polymer emulsion was obtained in the same manner as in Example 1, except that only 100 parts by weight of vinyl acetate was used instead of 100 parts by weight of the mixed monomer.

The obtained polymer emulsion has a solid content concentration of 50% by weight.
, a viscosity of 1,500 CP1 and a molecular weight of 100,000.

Comparative Example 2 A polymer emulsion was obtained in the same manner as Example 1 except that sodium dodecylbenzenesulfonate was used in place of polyoxyethylene polyoxypropylene.

The obtained polymer emulsion has a solid content concentration of 50% by weight.
, viscosity 5,000 CP1 molecular weight 140,000.

Comparative Example 3 A polymer emulsion was obtained in the same manner as in Example 1 except that methacrylic acid was used in place of dimethylaminoethyl methacrylate.

The obtained polymer emulsion has a solid content concentration of 50% by weight.
, a viscosity of 3,500 cP and a molecular weight of 150,000.

Comparative Example 4 A polymer emulsion was obtained in the same manner as in Example 1, except that only vinyl acetate was used instead of the mixed monomer and polyvinyl alcohol was used instead of polyoxyethylene polyoxypropylene.

The obtained polymer emulsion has a solid content concentration of 50% by weight.
, a viscosity of 15,000 cP and a molecular weight of 120,000. Test Examples The adhesives for binding glass fibers obtained in Examples 1 to 5 and the polymer emulsions obtained in Comparative Examples 1 to 4 were used as samples to conduct tests for binding power, impregnability, and transparency according to the following methods.

The test results were as shown in Table 1. 1 Focusing power test 1 test Sample 3009/M2 was applied to a well-washed and dried glass plate, a 25 mm wide cotton cloth was pasted on it, and after drying, a cut was made in a width of 25 Tnm, and it was peeled off at 180° using a tensile test machine. The focusing force was measured from the adhesion force of the sample to the glass surface.

2. Impregnation and transparency A sample is attached to a glass fiber cloth to a solid content of 1% by weight, and the treated glass fiber cloth is impregnated with an unsaturated polyester resin liquid. The impregnation properties of the samples were thus measured.

After the unsaturated polyester resin liquid was cured, its transparency was observed.

Claims (1)

[Scope of Claims] 1. (a) A vinyl ester monomer and (b) one or more selected from dialkylaminoalkyl unsaturated acids, vinylpyridine, and vinylcarbazole as a nonionic surfactant. An adhesive for binding glass fibers for FRP, which is made of a copolymer emulsion obtained by emulsion polymerization in the presence of a copolymer. 2. The adhesive for binding glass fibers for FRP according to claim 1, wherein the vinyl ester monomer is vinyl acetate. 3. The adhesive for FRP glass fiber bundling according to claim 1 or 2, wherein the copolymer has a molecular weight of 100,000 or less.