JPS5947714B2 - Polyester resin composition for plastic solder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel polyester resin composition that can be effectively used as a plastic solder without volatile monomers or organic solvents.

Traditionally, lead solder has often been used as a sealant for the joints between metal plates in automobile bodies. pollute the environment.

The weight increase due to O-sealing material is noticeable.

Because of these problems, the development of a sealant to replace lead solder has been awaited.

The inventors of the present invention have conducted extensive research in order to develop a plastic solder that can be effectively used as a sealing material, particularly as a sealing material for automobile bodies, taking into consideration the following performance requirements, and have effectively achieved this objective.

Contains no volatile monomers or organic solvents that cause environmental pollution.

0. It has fluidity to the extent that it can be sealed at room temperature and viscosity to the extent that it does not cause sag.

Under baking conditions of O coating, for example, at 170° C. for 20 minutes or less, it is hardened to the extent that it can be polished and has sufficient strength.

○ No bubbles are generated during baking.

That is, (1) terephthalic acid component 25~ as the acid component
45 mol%, P-oxybenzoic acid component 15-35 mol%
and 20 to 60 mol% of aliphatic dicarboxylic acid components, and 25 to 95 mol% of ethylene glycol as alcohol components, 0 to 70 mol% of dialcohols other than ethylene glycol, and 5 to 70 mol% of trihydric or higher polyhydric alcohols. (1) Structural formula (Formula Inside, X is 0.0
L.《?卜《》Indicates a monovalent organic residue represented by a monoconvex structural formula.

) and (2) a monoglycidyl compound represented by the structural formula (wherein, Y represents a divalent organic residue represented by the structural formula of
Indicates an integer between ~5.

) and a diglycidyl compound represented by the formula (wherein, E
is the number of equivalents of glycidyl groups possessed by the mono- and diglycidyl compounds, C is the equivalent number of carboxyl groups possessed by the polyester resin, M is the number of equivalents of glycidyl groups possessed by the monoglycidyl compound, and D is the number of equivalents of glycidyl groups possessed by the diglycidyl compound.

The polyester resin composition obtained by simultaneously mixing the following components in a satisfying ratio satisfied the above-mentioned required performance. Polyesters that can be used in the present invention include dimethyl terephthalate and P-oxyethoxymethylbenzoate, which are transesterified using a dialcohol such as ethylene glycol and/or neopentyl glycol in the presence of a catalyst such as zinc acetate, to obtain a theoretical amount of polyester. After removing methanol, an aliphatic dicarboxylic acid is added to perform an esterification reaction, and then trimethyl phosphate and antimony trioxide are added as a catalyst, and a polycondensation reaction is performed at a temperature of 200 to 280°C under reduced pressure to achieve high polymerization. The average degree of polymerization is controlled to any value within the range of 1 to 10 by preparing a degree polyester, then adding an alcohol component mainly consisting of a polyhydric alcohol of trihydric or higher valence and carrying out a depolymerization reaction at 200 to 280 degrees Celsius. However, other methods are preferred, such as using dimethyl terephthalate, P-oxyethoxymethyl benzoate with a dialcohol such as ethylene glycol, neopentyl glycol, and a trihydric or higher polyhydric alcohol such as trimethylolpropane. Similarly, a polyester having an average degree of polymerization of 1 to 10 synthesized by carrying out a transesterification reaction in the presence of a compound, followed by an esterification reaction by adding an aliphatic dicarboxylic acid, or by subsequently carrying out a polycondensation reaction may also be used. I can do it.

Succinic anhydride is used as the acid anhydride to be added to such polyester, but if necessary, phthalic anhydride,
Acid anhydrides such as trimellitic anhydride and pyromellitic anhydride can also be used in combination.

These acid anhydrides have a temperature of 100 to 180°C, preferably 13
A polyester resin is prepared by adding it to the terminal hydroxyl group of polyester at 0 to 150°C. Subsequently, a monoglycidyl compound and a diglycidyl compound are added to the polyester resin at a temperature of 100° C. or lower, preferably 30 to 80° C., along with a filler such as titanium oxide, silica, talc, or carbon, if necessary. Inventive polyester resin compositions can be prepared. Further, a compound such as N-pencel-2-methylimidazole may be added to the polyester resin composition of the present invention as a curing catalyst depending on the case. The aliphatic dicarboxylic acids used in producing the polyester used in the present invention include saturated aliphatic dicarboxylic acids having 4 to 14 carbon atoms such as succinic acid, adipic acid, azelaic acid, hivacic acid, and dodecanedicarboxylic acid; Other dialcohols include neopentyl glycol, 1
, 2-propanediol, 1,3-propanediol,
1,3-butanediol, 1,4-butanediol, 1
, 6-hexanediol, cyclohexanedimethanol, diethylene glycol, etc. Trivalent or higher polyhydric alcohols include glycerin, trimethylolethane,
These include trimethylolpropane, pentalythritol, dipentaerythritol, and mannitol.

Next, the present invention will be specifically explained by showing examples and reference examples.

Examples 1 to 5 Dimethyl terephthalate (hereinafter DM
Abbreviated as T.

), P-oxyethoxymethylbenzoate (hereinafter 0E
Abbreviated as BM. ), ethylene glycol (hereinafter abbreviated as EG), neopentyl glycol (hereinafter abbreviated as NPG)
, diethylene glycol (hereinafter abbreviated as DEG) and 1 x 10-3 mol of zinc acetate as a catalyst were placed in a stainless steel autoclave, and a transesterification reaction was carried out at 150 to 250°C to remove the theoretical amount of methanol. (hereinafter abbreviated as ADA), azelaic acid (hereinafter referred to as AZA)
It is abbreviated as ), an aliphatic dicarboxylic acid selected from hyvacic acid (hereinafter abbreviated as SEA) was added to perform an esterification reaction, and then 2 x 10-3 mol of trimethyl phosphate and 2 x 10-3 mol of antimony trioxide were added. In addition, 270℃
A polyester with a high degree of polymerization having an intrinsic viscosity (measured at 20° C. in a mixed solvent of equal weights of phenol and tetrachloroethane) of 0.64 to 0.66 was prepared by carrying out a polycondensation reaction at a reduced pressure of 0.5 rpm LHV. Next, trimethylolpropane (hereinafter abbreviated as TP) was added to the high polymerization degree polyester prepared as described above in the amount shown in Table 1.

), pentaerythritol (hereinafter abbreviated as PE), NP
Add a polyhydric or dihydric alcohol selected from G to 2
Polyesters shown in Table 2 were prepared by carrying out a depolymerization reaction under a nitrogen pressure of 80" C.2/1.
Succinic anhydride (hereinafter SUA) in the amount shown in Table 3 at 50°C
Abbreviated as D.

), trimellitic anhydride (hereinafter referred to as TMAD) if necessary
It is abbreviated as ) was added to prepare the polyester resin shown in Table 3. phenyl glycidyl ether (hereinafter referred to as PG)
It is abbreviated as E.

), epi-bis type epoxy resin with epoxy equivalent of 180 (
YD-128X diglycidyl phthalate manufactured by Tobu Kasei Co., Ltd. (hereinafter abbreviated as DGP) was blended at 60°C to prepare the polyester resin composition shown in Table 4. In addition, Table 4
The polyester resin compositions of Examples 1 to 5 were all in the form of a sol at room temperature.

After adding and kneading 1 part by weight of N-benzyl-2-methyl-imidazole as a catalyst per 100 parts by weight of each polyester resin composition shown in Table 4, 50 x 150 x 1 (m
The following test was carried out by applying a polyester resin composition to a film thickness of 1500 μm on a steel plate of 300 μm/m) and baking it at 170° C. for 20 minutes, and the results shown in Table 5 were obtained. (
4) Eriksen test: Based on JIS Z2247.

(2) Pencil hardness: According to JISK54OO.

Subsequently, each polyester resin composition (containing catalyst) was
25 x 12.5 (m/m) on a steel plate of x 100 x l (m/m)
/m) area to a thickness of 20μ, overlapped 25 x 12.5 (m/m) areas of the same steel plate, held with clips, baked at 170℃ for 20 minutes, and then tested using an Instron tensile tester. The shear strength was measured based on JIS K685O, and the results shown in Table 6 were obtained. Example 6~
9 Add cyclohexyl glycidyl ether (hereinafter referred to as C
Abbreviated as GE.

) Cyclohexane monocarboxylic acid glycidyl ester (
Hereinafter abbreviated as CMDG. ) or benzoic acid glycidyl ester (hereinafter abbreviated as BGE), hydrogenated phthalate diglycidyl ester (hereinafter abbreviated as DGHP) or hydrogenated bisphenol A diglycidyl ether (hereinafter abbreviated as DGHP) in the amount shown in Table 7 as a diglycidyl compound. It is abbreviated as HBAG.
) were blended at 60°C to prepare the polyester resin compositions shown in Table 7. The polyester resin compositions of Examples 6 to 9 shown in Table 7 were all in sol form at room temperature, and were baked in the same manner as Examples 1 to 5 and measured for Erichsen test and pencil hardness. Table 8 The results shown are obtained.

Reference Examples 1 to 4 PGE and YD in the amounts shown in Table 9 were added to the same polyester resin as the polyester resin shown in Example 1 in Table 3.
-128 was blended at 60°C to prepare the polyester resin composition shown in Table 9.

The polyester resin compositions of Reference Examples 2 and 3 had no fluidity at room temperature and could not form a sol.

That is, as seen in Reference Example 2, even if the same polyester resin as that shown in Example 1 is used and the E/C is set to 2.06, which is the same as in Example 1, PGE cannot be blended. If the M/D was less than 0.2, the plastic solder would not exhibit adequate fluidity at room temperature, which is required for plastic solder, and was not preferred. Further, as seen in Reference Example 3, even if M/D was set to 0.54, which is the same as in the example, it was similarly not preferable when E/C was less than 1.5.

After adding and kneading N-benzyl-2-methyl-imidazole as a catalyst per 100 parts by weight of the polyester resin compositions of Reference Examples 1 and 4, tests were conducted in the same manner as in the examples.
The results shown in Table 10 were obtained.

Reference Example 5 Same as Experimental Feed 1, but with TPO. A depolymerization reaction was carried out using 5 mol of polyester having an average degree of polymerization of 20.

This was followed by the same procedure as in Example 1, except that 1.5 mol of SU
After adding AD, PGEl. O8 mol, YD-1,2
Blending 81.00 moles E/C=205M/D=
A 0.54 polyester resin composition was prepared. Such a polyester resin composition using a polyester having an average degree of polymerization of 20 had no fluidity in the room and could not form a sol.

The present invention relates to a sol-like polyester resin composition that has fluidity at room temperature and can be cured by baking at a relatively low temperature of about 170C for a relatively short time of about 20 minutes. This polyester resin composition is a new material that can be effectively used as a sealant for joints in automobile bodies as a plastic solder.

As is clear from the comparison between Examples and Reference Examples, the average degree of polymerization of polyester, the balance between carboxyl groups and glycidyl groups contained in the polyester resin composition, and the balance between monoglycidyl compounds and diglycidyl compounds can be controlled at room temperature. It is extremely important to maintain fluidity and performance after baking.

Claims (1)

[Scope of Claims] 1 (I) 25 to 45 mol% of a terephthalic acid component, 15 to 35 mol% of a P-oxybenzoic acid component, and 20 to 60 mol% of a fatty acid dicarboxylic acid component as acid components, and 25 to 25 mol% of ethylene glycol as an alcohol component. 95 mol%, 0 to 70 mol% of dialcohols other than ethylene glycol, and 5 to 70 mol% of trihydric or higher polyhydric alcohols, with an average degree of polymerization of 1 to 10. At least 80% of the hydroxyl groups possessed by succinic anhydride Polyester resin obtained by adding acid or acid anhydride whose main component is succinic anhydride, and (II) (1) Structural formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, X is ▲ mathematical formula, There are chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ A monovalent organic compound represented by the structural formula ) and (2) Structural formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, Y is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼▲ Numerical formulas, chemical formulas, tables, etc.) ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Indicates a divalent organic residue represented by the structural formula, where n is an integer from 0 to 5.) A diglycidyl compound represented by the formula 1.5≦E
/C≦2.5, 0.2≦M/D≦0.8 (wherein, E is the number of equivalents of the glycidyl group possessed by the mono- and diglycidyl compounds, C is the number of equivalents of the carboxyl group possessed by the polyester resin, and M is the number of equivalents of the carboxyl group possessed by the polyester resin. The equivalent number D of glycidyl groups in a monoglycidyl compound indicates the number of equivalents of glycidyl groups in a diglycidyl compound.