JPS6248965B2 - - Google Patents

Description

[Detailed description of the invention]

Since the curing of unsaturated polyester resins is inhibited by oxygen, air-drying unsaturated polyester resins using drying oil fatty acids, dicyclopentadiene, βγ-unsaturated ether alcohols, etc. have been developed. Moreover, these air-drying unsaturated polyester resins are used in wood paints and vehicle refinish paints as representative solvent-free liquid resins because the styrene monomer used as a solvent reacts nearly 100% as a crosslinking agent during curing. . However, although styrene monomer reacts nearly 100% during curing, it has a relatively high vapor pressure, so it usually evaporates a small amount during painting or after painting until it hardens. Ta. As a result, the styrene monomer volatilized into the atmosphere causes deterioration of the working environment and air pollution. In general, in order to reduce the concentration of volatile styrene in air-drying unsaturated polyester resins, there are two methods: 1. Using monomers with low vapor pressure other than styrene monomers, 2. Making air-drying unsaturated polyester resins have lower molecular weight and making them air-dryable. Possible methods include reducing the molar fraction of styrene monomer in the unsaturated polyester resin, and adding a substance that suppresses volatilization of the styrene monomer to the air-drying unsaturated polyester resin. However, method 1) has problems such as low vapor pressure monomers themselves generally have high viscosity, so they have little dilution effect, and copolymerizability with air-drying unsaturated polyester resins is generally inferior to styrene. There is. In method 2), it is conceivable that various physical properties of the air-drying unsaturated polyester resin deteriorate. Furthermore, the method 3) is not preferable because there is no suitable detergent other than wax, and there is a limit to the amount of detergent that can be added, which adversely affects the coating film. The present invention provides an air-drying resin and a method for producing an air-drying resin composition that has properties similar to that of an air-drying unsaturated polyester resin even if it has a low molecular weight and has reduced volatilization of styrene. . The present invention relates to the reaction of αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, water and dicyclopentadiene, or αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, and hydroxylated dicyclopentadiene. The resulting compound () is reacted with 0.3 to 1.3 equivalents of a monoepoxy compound having a βγ-unsaturated ether residue relative to the carboxyl group of the compound () to form a compound (), and then to the compound (),
A method for producing an air-drying resin by reacting an approximately equivalent amount of polyfunctional isocyanate to compound (), and αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, water and dicyclopentadiene or αβ-unsaturated dicarboxylic acid. A monoepoxy compound having a βγ-unsaturated ether residue relative to the carboxyl group of compound (I) is added to the compound () obtained by reacting an acid or αβ-unsaturated dicarboxylic acid anhydride with hydroxylated dicyclopentadiene. 60 to 95 parts by weight of an air-drying resin obtained by reacting 0.9 to 1.3 equivalents to form a compound (), and then reacting the compound () with a polyfunctional isocyanate in an approximately equivalent amount to the compound () and an ethylene polymerizable resin. The present invention relates to a method for producing an air-drying resin composition in which 5 to 40 parts by weight of monomers are mixed. In the present invention, maleic acid, fumaric acid, citraconic acid, etc. are used as the αβ-unsaturated dicarboxylic acid, and maleic anhydride, citraconic anhydride, etc. are used as the αβ-unsaturated dicarboxylic acid anhydride. αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, water, and dicyclopentadiene are mixed and reacted in approximately equal moles. -Unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic anhydride is 0.9
The range is approximately 1.1 mol. When αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride and hydroxylated dicyclopentadiene are used, the moles thereof are approximately equal, and αβ- The amount of unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride is approximately 0.9 to 1.1 mol. reaction temperature,
There is no particular restriction on the reaction time, etc., and preferably 110
React at 130°C for 2-7 hours. Hydroxylated dicyclopentadiene is a compound obtained by reacting water and dicyclopentadiene under an acidic catalyst, and its production method is known. Allyl glycidyl ether is mainly used as the monoepoxy compound having a βγ-unsaturated ether residue to be reacted with this compound (), but ethylene glycol monoallyl monoglycidyl ether, glycerin diallyl monoglycidyl ether, etc. can also be used. You can also do it. Compound () and a monoepoxy compound having a βγ-unsaturated ether residue are treated under an inert gas flow such as nitrogen gas, using a quaternary ammonium salt such as trimethylbenzylammonium chloride as a polymerization catalyst, and as necessary. Depending on the situation, a polymerization inhibitor such as hydroquinone, p-benzoquinone, or p-tert-butylcatechol is used, preferably 80 to
It is reacted at 150℃ to form the compound (). Initially, the reaction generates heat, and the progress of the reaction can be determined by the decrease in the acid value. To measure the acid value, take out the reactants during the reaction and use JIS K 6901.
The reaction is usually completed when the acid value reaches 40 or less. The monoepoxy compound having a βγ-unsaturated ether residue is reacted in an amount of 0.9 to 1.3 equivalents based on the carboxyl group of the compound (). Outside this range, many terminal reactants remain and drying of the coating film is delayed. Examples of polyfunctional isocyanates include 2,4- or 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, hexamethylene diisocyanate, triphenylmethane triisocyanate, and 3,3',4,4'-diphenyl. Compounds having an isocyanate group obtained by reacting methane tetraisocyanate, diisocyanates with polyhydric alcohols such as propanediol, trimethylolpropane, and pentaerythritol, diisocyanate trimers having an isocyanurate ring, and the like are used. This polyfunctional isocyanate is used in an approximately equivalent amount to the compound (). If the polyfunctional isocyanate is less than approximately equivalent to the compound (), unreacted substances will remain, delaying the drying of the coating film, reducing properties such as hardness, and causing the polyfunctional isocyanate to react with the compound (). If the amount is more than approximately equivalent, the amount of residual isocyanate groups becomes large and the viscosity of the varnish increases over time, which is not preferable. Approximately equivalent means a range of 0.9 to 1.3 equivalents. Examples of the ethylene polymerizable monomer which is the other component of the resin composition in the present invention include styrene, divinylbenzene, vinyltoluene, methyl acrylate, methyl methacrylate, diallyl phthalate, triallyl cyanurate, ethylene glycol, , 3- or 1,6-hexanediol, diacrylate or dimethacrylate, tri- or tetraacrylate such as trimethylolpropane, pentaerythritol, and the like. These ethylene-based polymerizable monomers may be mixed with one or two types depending on workability etc.
More than one species is used depending on the desired characteristics. Furthermore, the amounts of the air-drying resin and the ethylene polymerizable monomer in the air-drying resin composition obtained by the present invention will be explained. If the amount of air-drying resin is less than 60 parts by weight and the amount of ethylene-based polymerizable monomer exceeds 40 parts by weight, a high solid content air-drying resin composition will not be obtained, and the amount of air-drying resin will be too low. If the amount of the ethylene polymerizable monomer exceeds 95 parts by weight and is less than 5 parts by weight, the resin composition will have a high viscosity, poor workability, and poor physical properties. The air-drying resin composition obtained by the present invention can be cured with peroxide or redox cured with a combination of peroxide and a curing accelerator. Examples of peroxides include benzoyl peroxide,
Methyl ethyl ketone peroxide, kyumene hydroperoxide, etc. can be used, and as curing accelerators, for example, metal soaps such as cobalt, copper, and manganese, tertiary amines, β-diketones, etc. can be used, but the amount and method used are limited. There are no particular restrictions on this. It should be noted that there is no problem in adding desired amounts of pigments, dyes, etc. to the air-drying resin composition of the present invention, if necessary. Examples of the present invention will be described. Example 1 1 mole of dicyclopentadiene, 1 mole of maleic anhydride, and 1 mole of water were charged into a four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen gas blowing tube, and a stirring rod, and heated to 130°C. After 4 hours of reaction, the acid value reached 220. Then, 1 mol of allyl glycidyl ether (per equivalent of carboxyl group)
1.1 equivalent) and 0.001 mol of trimethylbenzylammonium chloride were charged and reacted at the same temperature. When the acid value reached 10, the temperature was lowered to 60°C, and 0.5 mol of tolylene diisocyanate (approximately 1.1 equivalents relative to the reaction product) was added dropwise. Heat to 60℃ for 2 hours,
An air-drying resin () was obtained. Example 2 Using the same apparatus as in Example 1, 1 mole of hydroxylated dicyclopentadiene and 1 mole of maleic anhydride were charged and reacted at 130°C for 3 hours to give an acid value of 216.
It became. Then, the temperature was lowered to 110°C, 1 mol of allyl glycidyl ether (1.1 equivalent to carboxyl group) and 0.001 mol of trimethylbenzylammonium chloride were added, and when the acid value reached 20,
The temperature was lowered to 60℃, and 0.5 mol of diphenylmethane-4,4'-diisocyanate (approximately 1.2
(equivalent amount) was added dropwise and reacted for 3 hours to obtain an air-drying resin (). Example 3 Using the same apparatus as in Example 1, 1 mole of maleic anhydride, 1 mole of water, and 1 mole of dicyclopentadiene were charged, heated to 140°C, and reacted for 4 hours.
Next, 0.9 mol of glycerin diallyl monoglycidyl ether and 0.001 mol of trimethylbenzylammonium chloride were charged and reacted for 5 hours. When the acid value reached 14, the temperature was lowered to 60°C and 0.45 mol of hexamethylene diisocyanate (reaction product (approximately 1.1 equivalents) was added dropwise. The reaction was carried out for 3 hours to obtain an air-drying resin (2). Comparative Example 1 In the same apparatus as Example 1, 1 mol of maleic anhydride,
0.5 mol of propylene glycol, 0.5 mol of diethylene glycol, and 3.0 mol of trimethylolpropane diallyl ether were charged and reacted at 180°C.
After 10 hours, an air-drying unsaturated polyester resin () with an acid value of 30 was obtained. Comparative Example 2 An air-drying unsaturated polyester resin () having an acid value of 27 was obtained in the same manner as in Comparative Example 1 except that the propylene glycol used in Comparative Example 1 was changed to 0.4 mol. Resins () to () were mixed with polymerizable monomers in the proportions (parts by weight) shown in the column of resin composition in Table 1. At this time, 0.02 parts by weight of hydroquinone was added to 100 parts by weight of the resin composition. Evaluation of resin composition characteristics was performed in accordance with JIS K 6901. The amount of volatilized styrene was measured by the following method. 50g of resin composition on a 300 x 300 (mm) glass plate
Apply it evenly and cover with a 340 x 340 x 300 (mm) box. The styrene concentration was measured at box 100 (mm) 5 minutes after application using a Kitagawa detector tube. To 100 parts by weight of the air-drying resin composition diluted with styrene listed in Table 1, 0.5 parts by weight of cobalt naphthenate and 0.5 parts by weight of methyl ethyl ketone peroxide with a metal content of 6% (wt%) were added to polish mild steel. After applying 8 g onto a plate (150 x 150 mm, thickness 0.3 mm), it was left in an air bath at 25°C for a day and night, and the properties of the resulting coating film were evaluated by the following method. (i) Drying time: Even if you press your finger in the air bath,
It is expressed as the time until no fingerprints remain on the coating film. (ii) Pencil hardness: Performed according to the method of JIS K 5652 and showed the minimum hardness that would cause scratches. (iii) Adhesion: Tape peeling of the goblin test,
This was done in accordance with JIS K 5400. (iv) Surface smoothness: Visually judged good as 〇 and poor as bad.

【table】

[Table] The air-drying resin obtained by the present invention has a low molecular weight and a high solids content, making it possible to significantly reduce the amount of volatilized styrene in conventional air-drying unsaturated polyester resins. be. Furthermore, the air-drying resin composition obtained by the present invention is particularly superior in 1) smoothness of the coating film, 2) adhesion, etc., as compared to conventional air-drying unsaturated polyester resins.

Claims (1)

[Scope of Claims] 1 αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, water and dicyclopentadiene or αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride and hydroxylated dicyclo The compound () obtained by reacting pentadiene is reacted with 0.9 to 1.3 equivalents of a monoepoxy compound having a βγ-unsaturated ether residue relative to the carboxyl group of the compound () to form the compound (), and then to the compound (). , a method for producing an air-drying resin, which comprises reacting a polyfunctional isocyanate in an approximately equivalent amount to the compound (). 2. Obtained by reacting αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, water and dicyclopentadiene, or αβ-unsaturated dicarboxylic acid or αβ-unsaturated dicarboxylic acid anhydride, and hydroxylated dicyclopentadiene. The compound () is reacted with 0.9 to 1.3 equivalents of a monoepoxy compound having a βγ-unsaturated ether residue relative to the carboxyl group of the compound () to form a compound (), and then the compound () is reacted with An air-drying resin composition characterized by mixing 60 to 95 parts by weight of an air-drying resin obtained by reacting an approximately equivalent amount of a polyfunctional isocyanate with 5 to 40 parts by weight of an ethylene polymerizable monomer. Manufacturing method.