JP2602841B2 - Resin composition for adhesives - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a resin composition for an adhesive having excellent corrosion resistance and impact resistance at low temperatures.

(Prior art) FR combining unsaturated polyester resin and glass fiber
Septic tanks, which are P products, are widely used in areas without sewage facilities, but adhesives using unsaturated polyester resin are used to mount the partition plates in the septic tanks. FRP for septic tanks is used for night soil treatment, so it needs to have considerable corrosion resistance, but the adhesive also needs to have corrosion resistance. This is because, when the partition plate is attached with an adhesive having poor corrosion resistance, the adhesive is eroded by human excreta and penetrates, so that the urine leaks into the next tank, thereby lowering the purification ability.

On the other hand, when the septic tank is transported or implemented in trucks in winter, the partition plate may peel off due to vibration or impact. For this reason, even after the partition plate is fixed with an adhesive, it is further screwed to prevent peeling of the partition plate due to vibration or impact, and the adhesive is merely used as a filler.

It is well known that the corrosion resistance and the impact resistance at low temperature are satisfied independently. In order to improve the corrosion resistance, it is preferable to lower the ester group concentration or terminal group concentration in the unsaturated polyester resin or to raise the heat distortion temperature of the cured product. As a method of lowering the terminal group concentration, a method of increasing the degree of polymerization of the unsaturated polyester has been adopted. As a method for increasing the heat distortion temperature of the cured product, a method of using a rigid material having a benzene skeleton or the like in a molecule or a method of increasing the degree of unsaturation of unsaturated polyester is adopted. Next, as a method of lowering the ester group concentration, a method of increasing the use ratio of a polymerizable monomer such as styrene that does not contain an ester group is employed. This method tends to increase the heat distortion temperature of the cured product. However, the use of a high molecular weight material, which is another method of lowering the ester group concentration, is not used because the effect is not remarkable because the heat distortion temperature of the cured product is lowered, and the decrease in the heat distortion temperature of the cured product is small. Although the resin containing 1,2-bis [palla (2-hydroxy-n-propoxy) -phenyl] propane as an alcohol component has excellent corrosion resistance, the cured product is hard and no improvement in impact resistance can be expected.

On the other hand, in order to improve the impact resistance at low temperatures, a long-chain material may be used, or the unsaturated polyester of the unsaturated polyester may be reduced to a soft unsaturated polyester resin. In other words, in order to increase the impact resistance at low temperatures, it is necessary to use a resin having a low heat distortion temperature of the cured product, which is the opposite of the method for improving the corrosion resistance.

(Problems to be Solved by the Invention) As described above, methods for satisfying the corrosion resistance of the unsaturated polyester resin composition and impact resistance at low temperature are well known, but methods for satisfying both at the same time are known. Absent.
For this reason, in order to maintain the corrosion resistance, which is an essential property of the product, it is necessary to fix the septic tank partition with screws, or cracks and peeling occur during truck transport and enforcement in winter.

The present invention provides a resin composition for an adhesive which simultaneously satisfies both corrosion resistance and low-temperature impact resistance.

(Means for Solving the Problems) The present invention relates to a thermal polymer of unsaturated fatty acid and / or 5 to 30% by weight of an α, β-unsaturated dibasic acid based on the total amount of an acid component and an alcohol component. A number average molecular weight of 2,000 to 4,000 obtained by reacting an acid component and an alcohol component containing a polyalkylene glycol adduct of bisphenol A having a molecular weight of 450 to 1,000 in an amount of 15 to 50% by weight based on the total amount of the acid component and the alcohol component. The unsaturated polyester is in the range of 40 to 80 parts by weight, the polymerizable monomer is in the range of 20 to 60 parts by weight, and the total amount of the unsaturated polyester and the polymerizable monomer is 10 to 10 parts by weight.
The present invention relates to a resin composition for an adhesive containing 0 parts by weight of an unsaturated polyester resin.

The α, β-unsaturated dibasic acid used in the present invention includes maleic acid, fumaric acid, itaconic acid, citraconic acid and the like, and also includes these acid anhydrides. The amount used is 5 to 30 with respect to the total amount of the acid component and the alcohol component.
% By weight. If the amount is less than 5% by weight, the corrosion resistance deteriorates. If the amount is more than 30% by weight, the cured product becomes high, and the impact resistance at low temperatures becomes almost equal to that of the conventional adhesive.

As the unsaturated fatty acid thermal polymer, two unsaturated fatty acids are used.
A dimer acid polymerized by molecular thermal polymerization, a trimer acid obtained by thermally polymerizing the dimer acid, a mixture of dimer acid and trimer acid, and the like are used. These are already known compounds. The adduct of a polyalkylene glycol of bisphenol A having a molecular weight of 450 to 1000 is obtained by adding a polyalkylene glycol having a repeating number of 2 to 11 of an alkylene glycol having 3 to 4 carbon atoms to bisphenol A. It is a known compound. The thermopolymer of unsaturated fatty acid and / or the polyalkylene glycol adduct of bisphenol A having a molecular weight of 450 to 1000 is used in an amount of 15 to 50% by weight based on the total amount of the acid component and the alcohol. If the amount is less than 15% by weight, the corrosion resistance may be inferior and the impact resistance at low temperatures may be inferior. If the amount is more than 50% by weight, the corrosion resistance may be deteriorated.

Acid components other than those described above include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, succinic acid, adipic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, endmethylenetetrahydrophthalic acid, hettoic acid, tetrahedral acid Chlorophthalic acid, tetrabromophthalic acid and their acid anhydrides,
These may be used in combination of two or more.

On the other hand, the alcohol components include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
There are neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol and the like, and two or more of these may be used in combination.

To obtain an unsaturated polyester with a number average molecular weight of 2,000 to 4,000, which can be obtained by reacting an acid component and an alcohol component,
The molar ratio of the alcohol component to the acid component may be 1.0 to 1.1, and the degree of polymerization may be 90 to 97%. If the number average molecular weight of the unsaturated polyester is less than 2,000, not only mechanical strength such as adhesive strength is lowered, but also terminal group concentration is increased and corrosion resistance is poor. When the number average molecular weight is more than 4000, the viscosity of the unsaturated polyester becomes high, and the workability as an adhesive becomes poor. The reaction between the acid component and the alcohol component is carried out by a commonly used method.

Unsaturated polyester is unsaturated polyester resin 100
It is in the range of 40 to 80 parts by weight with respect to parts by weight. The polymerizable monomer is based on 100 parts by weight of the unsaturated polyester.
It is in the range of 20 to 60 parts by weight which is the balance of the unsaturated polyester. If the amount of the unsaturated polyester is less than 40 parts by weight, the viscosity of the adhesive becomes low and sagging occurs, making it difficult to seal. If the amount is more than 80 parts by weight, the viscosity of the adhesive becomes high and the workability is deteriorated, and nests are formed and the adhesive strength is reduced.

Polymerizable monomers include styrene, α-methylstyrene,
Vinyltoluene, chlorostyrene, divinylbenzene,
There are acrylic acid, methacrylic acid and its alkyl ester, vinyl acetate, acrylonitrile, trimethylolpropane diallyl ether, diallyl phthalate and the like, and two or more of these may be used in combination.

As a curing accelerator, diacyl peroxide-based curing agents such as benzoyl peroxide and lauroyl peroxide; ketone peroxides such as dialkyl alanines, methyl ethyl ketone peroxide, and acetylacetone peroxide; and cumene hydroperoxide. For a hydroperoxide-based curing agent such as t-butyl hydroperoxide, an organic acid salt of cobalt or vanadium can be used. The amount of these used is optional depending on the curing time and the amount of the curing agent, but usually 0.05 to 0.5% by weight of the dialkylaniline relative to the unsaturated polyester resin, and 0.005 to 0.1% of the organic acid salt of cobalt or vanadium as the metal amount. Used in the range of weight percent. The amount of the curing agent used may be in the range of 0.3 to 4% by weight based on the unsaturated polyester resin.

Although the types and amounts of the compounds essential to the present invention have been described above, the resin composition for an adhesive of the present invention contains fillers such as calcium carbonate, clay, gypsum, and aluminum hydroxide, inorganic or organic pigments, Polymerization inhibitors such as hydroquinone and t-butylcatechol can be added.

 Next, the present invention will be described with reference to examples.

The corrosion resistance test of the resin composition for adhesives was conducted according to JIS A410.
The test was performed according to JIS K 5400, the impact resistance method B, and the test piece was prepared in the same manner as the tensile shear stress test piece shown in ASTM D2733. Tensile shear stress tests were performed using specimens of the shape shown in SATM D 2733, except that the joint length was 20 mm.
The test was performed at 23 ° C. with a pulling speed of 0.5 cm / min. For the FRP of these test pieces, a 3 mm thick plate was prepared by using three layers of Polyset 595APT (unsaturated polyester resin manufactured by Hitachi Chemical Co., Ltd.) and FEM450 (glass mat made by Fuji Fiberglass), and cut into a predetermined shape for use. . In addition, in order to form a test piece using the resin composition for an adhesive, the curing agent described in the example was mixed with the resin composition for an adhesive in an amount described in the example, and then the FR was mixed.
It adhered to the P plate, and the FRP plate was further laminated and cured at 25 ° C. After the curing, the protruding adhesive resin composition was scraped off.

(Example) An example of the present invention will be described. Parts are parts by weight.

Example 1 In a flask having a stirrer, a thermometer, an inert gas inlet, a decompressor and a total condenser, 297 g of isophthalic acid and 2
09g, Versadim 216 (Dimer acid manufactured by Henkel Japan) 6
00g and 676g of 1,3-butanediol were charged, and the temperature was raised in an inert gas atmosphere to proceed the reaction. Two hours later, the temperature was raised to 200 ° C, and the temperature was kept at 200 ° C until the acid value reached 20. The reaction solution was rapidly cooled to 80 ° C., charged with 280 g of maleic anhydride, and heated again to 200 ° C. in an inert gas atmosphere to proceed with the reaction to obtain 1860 g of unsaturated polyester A having an acid value of 15 and a number average molecular weight of 2870. 67 parts of the unsaturated polyester A was dissolved in 33 parts of styrene containing 0.06% by weight of hydroquinone at 100 ° C. to obtain an unsaturated polyester resin A. This unsaturated polyester resin
To 100 parts of A, 1 part of cobalt octenoate (cobalt content: 6%, the same applies hereinafter) and 60 parts of calcium carbonate were mixed to obtain a resin composition A for an adhesive. 1% by weight of methyl ethyl ketone peroxide was added to and mixed with the resin composition A for an adhesive, and a test piece was prepared by the method described above, and subjected to corrosion resistance, impact resistance and tensile shear stress tests. Table 1 shows the results.

Example 2 The same flask as in Example 1 was charged with 356 g of isophthalic acid, 209 g of adipic acid, 750 g of a polypropylene glycol adduct of bisphenol A having a molecular weight of 700, 321 g of 1,3-butanediol, and 218 g of propylene glycol. The reaction was repeated until the acid value reached 20, and then 350 g of maleic anhydride was charged. The reaction was performed again in the same manner as in Example 1 to obtain 2012 g of an unsaturated polyester B having an acid value of 16 and a number average molecular weight of 3040. 67 parts of the unsaturated polyester B was dissolved at 100 ° C. in 33 parts of styrene containing 0.06% by weight of hydroquinone to obtain an unsaturated polyester resin B. This unsaturated polyester resin
To 100 parts of B, 1 part of cobalt octenoate and 60 parts of calcium carbonate were mixed to obtain a resin composition B for an adhesive. This adhesive resin composition B was treated in the same manner as in Example 1, and the same test as in Example 1 was performed. Table 1 shows the results.

Comparative Example 1 Commercial adhesive polyset (trade name: putt, manufactured by Hitachi Chemical Co., Ltd.)
y) To 100 parts, 1 part of methyl ethyl ketone peroxide was added and mixed, and the same treatment as in Example 1 was performed, and the same test as in Example 1 was performed. Table 1 shows the results.

Comparative Example 2 The same flask as in Example 1 was charged with 297 g of isophthalic acid, 365 g of adipic acid, 600 g of soybean oil fatty acid and 676 g of 1,3-butanediol, and reacted as in Example 1 until the acid value reached 20. Thereafter, 175 g of maleic anhydride was charged and reacted again in the same manner as in Example 1 to obtain an acid value of 35 and a number average molecular weight of 82.
Thus, 1890 g of unsaturated polyester C having a yield of 0 was obtained. 67 parts of the unsaturated polyester C was dissolved at 100 ° C. in 33 parts of styrene containing 0.06% by weight of hydroquinone to obtain an unsaturated polyester resin C. To 100 parts of the unsaturated polyester C, 1 part of cobalt octenoate and 60 parts of calcium carbonate were mixed to obtain a resin composition C for an adhesive. This adhesive resin composition C was prepared in Example 1.
The same test as in Example 1 was performed by performing the same processing as in Example 1.
Table 1 shows the results.

(Effects of the Invention) As is clear from the examples, the resin composition for adhesives of the present invention has the same corrosion resistance and adhesive strength as conventional commercial adhesives, and particularly has excellent impact resistance at low temperatures. I have. As shown in Comparative Example 2, dimer acid and / or a polyalkylene glycol adduct of bisphenol A having a molecular weight of 450 to 1000 was not used, and the number average molecular weight of the unsaturated polyester was also 2,000 to 40.
When it is smaller than 00, the impact resistance is superior to the commercially available adhesive, but the corrosion resistance and the adhesive strength are remarkably inferior.

Claims (1)

(57) [Claims] 1. An α, β-unsaturated dibasic acid comprising 5 to 30% by weight, based on the total amount of an acid component and an alcohol component, of a thermopolymer of unsaturated fatty acid and / or bisphenol A having a molecular weight of 450 to 1,000. An unsaturated polyester having a number average molecular weight of 2,000 to 4,000 obtained by reacting an acid component and an alcohol component containing a polyalkylene glycol adduct in an amount of 15 to 50% by weight based on the total amount of the acid component and the alcohol component is 40 to 80 weight%. Parts for the polymerizable monomer, 20 to 60 parts by weight of the polymerizable monomer, and 100 parts by weight of the unsaturated polyester and the polymerizable monomer. Composition.