JPS5951579B2 - Pretreatment agent for bonding glass fiber reinforced unsaturated polyester resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pretreatment agent for bonding glass fiber-reinforced unsaturated polyester resins. The present invention relates to a bonding pretreatment agent that streamlines work and makes work that requires a lot of manpower extremely simple.

Conventionally, when bonding or repairing glass fiber-reinforced unsaturated polyester resins, in order to improve adhesive strength, the surface is usually roughened with sandpaper or the like, that is, sanding treatment is performed prior to applying adhesive.

This is because if secondary bonding is performed without sanding, the adhesive strength will be significantly lower than that with sanding, making it practically unusable. However, this sanding work must be carried out manually, especially in the case of repairs, since the shape of the object to be repaired is not constant.

Furthermore, if the object has small parts or gaps due to its shape, it may not be possible to sand those parts. Further, the dust generated by the sanding process also causes problems in terms of environmental hygiene. The present inventor has made extensive efforts to research and solve various inconveniences in this pretreatment process, and has developed a method for unsaturated polyester resin reinforced with glass fibers by applying a composition made of a specific compound instead of sanding. The inventors have discovered that these disadvantages can be overcome, and have completed the present invention.

In other words, simply using a solution of unsaturated polyester, curing accelerator, and ethylenically unsaturated monomer with a polyisocyanate compound added as a primer significantly improves the secondary bonding strength, which is greater than when sanding is performed. It was discovered that an adhesive strength of θ The pretreatment agent for bonding according to the present invention mainly consists of (a) unsaturated polyester, (
b) ethylenically unsaturated monomer, (c) curing accelerator, (d
) A resin solution containing polyisocyanate is dissolved in an organic solvent to make it easier to apply.

'5 The unsaturated polyester used in the present invention is normally used in the production of fiber-reinforced molded products, and is esterified using polyhydric alcohol, unsaturated polybasic acid, and optionally an appropriate amount of saturated polybasic acid as main raw materials. Manufactured by reaction.

An unsaturated polybasic acid is a compound having 1 or more double bonds and 2 or more carboxyl groups in one molecule. For example, maleic acid, maleic anhydride, fumaric acid, itaconic acid, etc. are unsaturated polybasic acids according to the present invention. Used in the production of polyester resin.

The unsaturated polyester according to the present invention can also be produced by using this unsaturated polybasic acid in combination with a saturated polybasic acid. mosquito·
Examples of saturated polybasic acids include isophthalic acid, phthalic anhydride, orthophthalic acid, and the like. In addition, examples of saturated polybasic acids which may be used as necessary to change the physical properties of the unsaturated polyester as a polymer include adipic acid, sebacic acid, tetrahydrophthalic acid, and chlordic acid.

Examples of polyhydric alcohols used in the production of the unsaturated polyester of the present invention include ethylene glycol, diethylene glycol, propylene glycol, neopentyl glycol, hydrogenated bisphenol A, 2,2'-
Di(4-hydroxypropoxyphenyl)propane, 2
, 2'-di(4-hydroxyethoxyphenyl)propane, and the like. Examples of ethylenically unsaturated monomers include styrene, vinyltoluene, chlorostyrene, vinyl acetate, acrylic esters, and methacrylic esters.

Typical polyisocyanates used in the present invention include 2,4-toluene diisocyanate, hexamethylene diisocyanate, 4,4'-1 methylene diphenyl diisocyanate, 1,5-naphthalene diisocyanate, and polymethylene polyphenylisocyanate. Can be mentioned.

Further, examples of the curing accelerator used in the present invention include catalysts used in urethanization reactions. Examples include metal soaps, lead naphthenate, potassium octoate.
, dibutyltin dilaurate, and tertiary amines such as triethylene diamine, N,N,N',N'-tetramethylhexamethylene diamine, and N-ethylmorpholine. There are a large number and variety of organic solvents that can be used to create suitable dilution solutions, including esters and ketones, and a variety of aromatic compounds.

Examples of such organic solvents include toluene, benzene, xylene, acetone, methyl ethyl ketone, tetrahydrofuran, ethyl acetate, carbon tetrachloride, methylene chloride, and chloroform. The pretreatment agent of the present invention has two components: a solution consisting of an unsaturated polyester, a curing accelerator, and a part of an ethylenically unsaturated monomer, and a solution consisting of a polyisocyanate and the remaining ethylenically unsaturated monomer. The bonding pretreatment agent of the present invention is provided by combining in the primer composition the following components used in the primer composition, but in total amounts within approximately the following weight percentage composition J: Unsaturated polyester 5 to 50% by weight Ethylenically unsaturated monomer 5 to 50% by weight Curing accelerator 0.1 to 5.0% by weight Polyisocyanate compound 5
~50% by weight Example 15 g of unsaturated polyester consisting of 1 mol of fumaric acid, polyoxypropylene (number of added moles: 2.0), 1 mol of bisphenol A, 1 mol of fumaric acid, polyoxypropylene (number of added moles: 16.0) ) Unsaturated polyester consisting of bisphenol Al mol 7
g, 14 parts of styrene monomer and 1 g of tin catalyst dibutyltin dilaurate as a curing accelerator are dissolved in 63 g of methylene dichloride.

On the other hand, a solution is prepared by dissolving 15 g of crude 4,4'-methylene diphenyl diisocyanate (trade name: Millionate MR, manufactured by Usumoto Polyurethane Co., Ltd.) and 5 g of methacrylic acid methyl ester in 80 g of methylene dichloride.

The obtained two types of solutions were mixed in equal amounts and applied uniformly to the bonding surface 2 of the base material 1 as shown in Fig. 1. After leaving it for 4 hours, the part to be bonded (25 mm width x 20 mm length) Chopped strand mat 3 impregnated with an unsaturated polyester styrene solution containing a curing accelerator was adhered using the single-lap method and sufficiently cured.
When the tensile shear strength was measured by a method similar to the method for measuring the tensile shear adhesive strength of IS-K685O adhesive, the tensile strength was 81 kg/Cm2, and the base material was destroyed.

The base materials used were one surf mat, two chopped strand mats, one roping mat, and two chopped strand mats, which were laminated and cured with the unsaturated polyester composition shown below. . Polyoxypropylene (2.0) Bisphenol A fumarate 50 parts Styrene monomer 50 parts Dimethylaniline (20%) 1.0 parts Cobalt naphthenate (6%) 0.5 parts Methyl ethyl ketone peroxide (55%) 1.0 parts Comparative Example 1 A base material of exactly the same quality as the base material used in Example 1 was used, and the bonding surface was not subjected to any treatment, but was bonded with a chopped strand mat impregnated with an unsaturated polyester styrene solution containing a hardening agent. After sufficiently curing, the tensile shear strength was measured in the same manner as in Example 1 and was found to be 28.5 kg/C.
There was only m2, and interfacial peeling occurred.

Comparative Example 2 Chopped using a base material of exactly the same quality as the base material used in Example 1, thoroughly sanding the adhesive surface with sandpaper and then impregnating it with an unsaturated polyester styrene solution to which a hardening agent was added. After adhering with a strand mat and sufficiently curing, the tensile shear strength was measured in the same manner as in Example 1 and found to be 75 kg/CTn2.

Example 2 15 g of an unsaturated polyester consisting of 0.8 mol of maleic acid, 0.2 mol of isophthalic acid and 1.0 mol of propylene glycol, 15 g of styrene monomer and 1 g of dibutyltin dilaurate are dissolved in 69 g of acetone.

On the other hand, 10 g of 2,4-toluene diisocyanate (product name: Sumidyur T-80: Sumitomo Bayer Urethane)
A solution is prepared by dissolving 5 g of butyl acrylate in 85 g of acetone. The resulting two types of solutions were mixed in equal amounts and applied to the adhesive surface of the base material, left for 4 hours, and then 65 parts of the above unsaturated polyester resin and 35 parts of styrene were applied to this joint (joint area 25 mm width x 20 mm length). BPO (
A chopped strand mat impregnated with a solution containing 1 part (benzoyl peroxide) was adhered using the same single wrap method as in Example 1, and after being sufficiently cured, the tensile shear strength was measured to be 80 kg/Cnl.
・It was hot. The fractured part was base metal fracture. The base materials are 1 surface mat, 2 chopped strand mats,
1 roping mat, 2 chopped strand mats
It is a sheet of FRP composite and is laminated with a solution of 65 parts of unsaturated polyester resin having the same composition as that used to create the pretreatment agent, 35 parts of styrene monomer, and 35 parts of BPOl.

Comparative Example 3 Using the same base material as in Example 2, the adhesive surface was thoroughly sanded with sandpaper and then bonded with a chopped strand mat impregnated with an unsaturated polyester styrene solution containing a hardening agent. After sufficient curing, the tensile shear strength was measured in the same manner as in Example 1 and found to be 74 kg/Cm2.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram for explaining a method for measuring tensile shear strength. 1... Base material, 2... Adhesive surface, 3...
...Chopped strand mat.

Claims (1)

[Claims] 1 (a) 5 to 50% by weight of unsaturated polyester, (b)
A composition containing as resin components 5 to 50% by weight of an ethylenically unsaturated monomer, (c) 0.1 to 5.0% by weight of a curing accelerator, and (d) 5 to 50% by weight of a polyisocyanate compound (the above-mentioned A pretreatment agent for bonding glass fiber-reinforced unsaturated polyester resin consisting of (% by weight is based on the entire resin component). 2. The pretreatment agent for bonding according to claim 1, wherein the ethylenically unsaturated monomer is styrene or methyl methacrylate. 3. The pretreatment agent for bonding according to claim 1, wherein the polyisocyanate compound is tolylene diisocyanate or 4,4'-methylene diphenyl diisocyanate.