JP3279964B2 - Method for producing unsaturated polyester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an unsaturated polyester and an unsaturated polyester resin composition, and more particularly, to a paint, an adhesive, a casting, a lining, a resin concrete, an artificial marble, and a fiber-reinforced plastic molding. The present invention relates to a method for producing an unsaturated polyester modified with dicyclopentadiene and an unsaturated polyester resin composition containing the above unsaturated polyester, which can be used for products and the like.

[0002]

2. Description of the Related Art Conventionally, molded articles made of unsaturated polyester have excellent moldability, strength characteristics, heat resistance, water resistance, etc., and are therefore suitably used for paints, adhesives, castings, linings and the like. ing. Further, the unsaturated polyester resin composition is impregnated with a reinforcing material such as glass fiber and carbon fiber to obtain a fiber reinforced plastic, a bathtub, a septic tank, a ship, a vehicle,
It is frequently used for materials such as tanks and housings.

[0003] The unsaturated polyester is generally a polyester obtained by a condensation reaction between a polybasic acid containing at least a part of an unsaturated acid and a polyhydric alcohol. And is called an unsaturated polyester.

[0004] A resin composition is obtained by mixing a radical polymerizable monomer (reactive diluent) such as a vinyl monomer with the unsaturated polyester, and the resin composition is cured in a mold, for example. Thereby, a molded product is obtained.

However, a molded article using the above unsaturated polyester undergoes about 8% curing shrinkage upon curing, so that the surface of the molded article may be sinker or the molded article may be warped. However, the dimensional accuracy is poor.

As a method of improving these disadvantages, it is known to use dicyclopentadiene as a raw material for unsaturated polyester. A resin composition using a so-called dicyclopentadiene-modified unsaturated polyester, which uses dicyclopentadiene as a part of the raw material, has low viscosity and excellent workability, and is a molded article using the unsaturated polyester. It is known that the surface of the steel has little sink mark and is excellent in hot water resistance.

A resin composition using a dicyclopentadiene-modified unsaturated polyester includes dicyclopentadiene,
By reacting maleic anhydride, water and a polyhydric alcohol, a dicyclopentadiene-modified unsaturated polyester is obtained, which is obtained by mixing a radical polymerizable monomer such as styrene.

As such a resin composition of an unsaturated polyester, for example, those disclosed in the following publications are known. First, JP-A-54-90285 discloses that dicyclopentadiene, maleic anhydride, and water
Polyester obtained by addition condensation reaction of partially esterified dicyclopentadiene carboxylic acid and polyhydric alcohol obtained by reacting at 0 ° C. or less, comprising styrene and polystyrene, low viscosity and electric properties, particularly A low shrinkage resin composition having excellent high-temperature insulation resistance is disclosed.

Japanese Patent Application Laid-Open No. 4-132714 discloses a dicyclopentadiene oligomer obtained by reacting dicyclopentadiene and maleic anhydride dropwise with water, a dicyclopentadiene oligomer obtained by further reacting with glycol, and a vinyl compound. A thermosetting resin composition comprising a polymerizable monomer and having significantly improved surface smoothness, dimensional stability (low warpage), and hot water resistance when formed into a molded product is disclosed.

Further, Japanese Patent Publication No. 6-74301 discloses an unsaturated polyester resin containing neopentyl glycol as a component, an unsaturated polyester resin containing dicyclopentadiene as a component, a thixotropic agent, and a polymerizable monomer. ,
An unsaturated polyester resin composition capable of providing a product having good surface smoothness is disclosed.

The above publication describes, as an example of the production of an unsaturated polyester resin containing dicyclopentadiene as a component, when a reaction mixture is obtained by adding maleic anhydride to a mixture of dicyclopentadiene and water. A method is disclosed in which the rate of addition of the maleic anhydride is set small so that the temperature of the reaction mixture becomes 130 ° C. or lower by utilizing the heat generated by the reaction. According to the above publication, after the addition of maleic anhydride is completed, heating is further continued at 130 ° C. for 3 hours, and then glycol is added to gradually raise the temperature to 210 ° C.
When the acid value becomes 25 or less, it is judged that the reaction is completed, and the mixture is cooled. Subsequently, hydroquinone and a styrene monomer are added to obtain the unsaturated polyester resin composition.

JP-T-62-500034 discloses a softened composition comprising a dicyclopentadiene-modified unsaturated polyester alkyd, a urethane oligomer and a non-resinous vinyl monomer. As a production example of the dicyclopentadiene-modified unsaturated polyester alkyd, there is disclosed a method of adding water exceeding a theoretical equivalent to maleic anhydride, subsequently adding dicyclopentadiene, reacting, and then reacting with polyol. I have.

[0013] Generally, the dicyclopentadiene-modified unsaturated polyester is formed by a dicyclopentadiene, maleic anhydride and water addition reaction step to form a dicyclopentenyl monoester of maleic acid, which is subsequently reacted with the addition reaction mixture; It is obtained by an esterification reaction step with a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid.

In the above-mentioned addition reaction step, first, maleic anhydride reacts with water to form maleic acid. Due to the strong dissociation of the primary carboxylic acid, dicyclopentadiene and the primary carboxylic acid of maleic acid are used without a catalyst. And as a result, an addition reaction product, dicyclopentenyl monoester of maleic acid, is produced. Since such a reaction generates a large amount of heat generated by the reaction, it is necessary to perform the reaction operation with great care so as to prevent runaway of the heat generated by the reaction.

[0015]

However, in the above-mentioned conventional method, for example, when maleic anhydride, water and dicyclopentadiene are preliminarily mixed with each other and heated in a reaction vessel of a reactor, a rapid reaction occurs. The reaction proceeds, and a sudden rise in temperature due to runaway of the reaction exotherm causes a rise in the pressure in the reaction vessel, which may cause a risk such as breakage of the reactor. Therefore, in the above case, it is conceivable to equip the reactor with a cooling device having a sufficient cooling capacity in order to avoid the above-mentioned danger, but there is a problem that the reactor becomes large and the cost is increased. Have.

In the above-mentioned conventional method, when the addition reaction step is carried out by adding water or maleic anhydride dropwise to a mixture of maleic anhydride and dicyclopentadiene or a mixture of water and dicyclopentadiene, And dicyclopentadiene, and water and dicyclopentadiene do not dissolve in each other, resulting in an inhomogeneous state. For this reason, in such a non-uniform reaction system, since the partial concentration of each raw material becomes non-uniform, it is difficult to control the heat generation, and there is a risk that the reaction heat will run away. Therefore, in the above case, there is a problem that the safety in the production of the unsaturated polyester is reduced, and if the cooling capacity is increased to avoid the runaway, the above-mentioned cost increase is caused.

Further, in the above-mentioned conventional method, in order to avoid the above-mentioned decrease in safety, water or maleic anhydride may be added dropwise while stirring the above mixture continuously and sufficiently. There is a need to constantly perform sufficient stirring, which causes a problem that it takes time to manufacture.

Furthermore, in the above-mentioned conventional method, a method of gradually adding dicyclopentadiene to maleic acid can be considered, but in order to make the reaction in a uniform liquid state,
Maleic acid is heated above its melting point (138-139 ° C) 14
It is necessary to heat to a temperature exceeding 0 ° C. to melt. However, when dicyclopentadiene is added at a temperature exceeding 140 ° C., dicyclopentadiene is decomposed to form cyclopentadiene. Since the above cyclopentadiene reacts with maleic acid to be a by-product of 5-norbornene-2,3-dicarboxylic acid, the dicyclopentenyl monoester of maleic acid is efficiently used at a temperature higher than 140 ° C. There is a problem in that the yield of the desired dicyclopentadiene-modified unsaturated polyester is reduced.

Furthermore, since the unsaturated polyester obtained by each of the conventional methods is produced in a heterogeneous system, the heat generated in the reaction in the reaction system is also non-uniform, and even if the stirring is sufficiently performed, Partially exceeding 140 ° C. is likely to occur. From this, as described above, the by-products that are likely to occur in the portion exceeding 140 ° C. are incorporated into the skeleton of the unsaturated polyester. Therefore, in the unsaturated polyester of the above-mentioned conventional method, for a molded product obtained by curing a resin composition containing the same, physical properties that a dicyclopentadiene-modified unsaturated polyester can be imparted to the molded product,
For example, there is a problem of deterioration of hot water.

An object of the present invention is to provide high safety and economy,
And good handling properties at low viscosity and, moreover, in the resulting molded article is to provide a manufacturing how the dicyclopentadiene-modified unsaturated polyester which is excellent in hot water resistance.

[0021]

Means for Solving the Problems In the process of obtaining dicyclopentenyl monoester of maleic acid, the present inventors have found that the addition of water at a stoichiometric equivalent or less to maleic anhydride reduces the precipitation of solids. Almost no liquid state can be maintained by maintaining a substantially uniform liquid state.Subsequently, the above reaction can be performed while avoiding runaway of reaction heat generation by gradually adding dicyclopentadiene. By controlling, a reaction mixture containing dicyclopentenyl monoester of maleic acid can be obtained, and then the reaction mixture is reacted with a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid, to obtain a heat-resistant mixture. We found that it is possible to produce low-viscosity, dicyclopentadiene-modified unsaturated polyester, which gives molded products with excellent aqueous properties. Thus, the present invention has been completed.

In order to solve the above problems, the method for producing an unsaturated polyester of the present invention comprises mixing maleic anhydride (A) and water (B) to form a mixture of 120 ° C. or more and 130 ° C. or less.
After reacting under the following conditions, the obtained reaction mixture is reacted with dicyclopentadiene (C), a first step represented by the following general formula (1), a reaction mixture of the first step, Reacting an alcohol or a polyhydric alcohol with a polybasic acid to obtain an unsaturated polyester modified with dicyclopentadiene (C). And the molar ratio (B / A) between the acid and maleic anhydride (A) is less than 1.

[0023]

Embedded image

In the above production method, the dicyclopentadiene (C) may be used in an amount of at least 20% by weight of the dicyclopentadiene (C) derived from the unsaturated polyester. It is desirable to add in one step.

According to the above production method, the molar ratio of water (B) to maleic anhydride (A) (B /
By setting A) to 1 or less, maleic anhydride can be effectively left in the reaction system of the first step. By adjusting or controlling the content of such residual maleic anhydride, the precipitation of solids in the reaction system of the first step can be suppressed, and the reaction system of the first step is maintained in a substantially liquid state. It is possible to proceed with. Further, in the above method, the first step
The molar ratio of water (B) to maleic anhydride (A) (B /
By setting A) to less than 1, the residual anhydrous maleic
The content of the acid can be further easily controlled. this thing
From, the reaction system of the first step is further advanced in a homogeneous system
Molding using unsaturated polyester
Product while avoiding deterioration of hot water resistance of the product.
, Maintaining its excellent physical properties, more efficiently,
And it can be manufactured safely.

Thus, in the above method, runaway of reaction heat generated easily when the reaction system in the first step becomes a heterogeneous system due to precipitation of solid matter, and generation of by-products due to local temperature rise Can be reduced. Therefore, in the above method, in the first step, the dicyclopentenyl monoester of maleic acid in which dicyclopentadiene (C) is added to maleic acid which is a water adduct of maleic anhydride (A) is safely and efficiently used. Can get well.

Subsequently, in the second step, the reaction mixture containing the dicyclopentenyl monoester of maleic acid is reacted with a polyhydric alcohol or a polyhydric alcohol with a polybasic acid to obtain dicyclopentadiene (C ), The unsaturated polyester modified by the method can be obtained safely and efficiently.

Therefore, in the above method, since the reaction system in the first step can be made a homogeneous system, runaway of reaction heat generated due to non-uniformity of the reaction system can be suppressed, so that a large cooling capacity for the runaway can be obtained. It is not necessary, and the generation of by-products due to the reaction of the heterogeneous system can also be reduced, and the by-products are incorporated into the skeleton of the unsaturated polyester. While maintaining excellent physical properties of the unsaturated polyester while avoiding deterioration of the polyester.

[0029]

In addition, for the above unsaturated polyester,
By setting the content of the dicyclopentenyl group derived from dicyclopentadiene (C) to 20% by weight or more, the obtained unsaturated polyester can have a low viscosity.

[0031]

[0032]

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below. The method for producing an unsaturated polyester of the present invention comprises a first step of obtaining a reaction mixture containing dicyclopentenyl monoester of maleic acid, and adding a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid to the reaction mixture. And reacting the dicyclopentenyl monoester of maleic acid with a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid to obtain a dicyclopentadiene-modified unsaturated polyester. the first step is to maleic anhydride (a), was added the theoretical equivalent of less than water (B), and the reaction of maleic anhydride (a) and water (B)
This is a method performed at a temperature of 120 ° C or more and 130 ° C or less . The reaction mixture of water (B) and maleic anhydride (A) in the first step contains unreacted water (B), maleic anhydride (A), and maleic acid after the reaction. .

According to the above method, in the first step, maleic anhydride can be effectively left in the reaction mixture by adding less than the stoichiometric amount of water (B). A substantially uniform liquid state in which almost no substance is deposited can be maintained by the residual maleic anhydride. Therefore, in the first step, the components to be reacted are prevented from being localized. Subsequently, by gradually adding dicyclopentadiene (C), the reaction system is maintained while maintaining a substantially uniform liquid state, thereby avoiding runaway of reaction heat generation and by-products which are likely to be caused by the heterogeneous system. By controlling, a reaction mixture containing dicyclopentenyl monoester of maleic acid can be obtained safely and efficiently.

In the above method, the added dicyclopentadiene (C) reacts rapidly with maleic acid to form dicyclopentenyl monoester of maleic acid because the reaction system is uniform. The residual amount of free dicyclopentadiene (C) can be suppressed,
Side reactions due to residual dicyclopentadiene (C) can also be prevented.

Next, in the second step, a polyhydric alcohol or a polyhydric alcohol and a polybasic acid are reacted with the reaction mixture to obtain a molded article having a low viscosity and excellent hot water resistance. A cyclopentadiene-modified unsaturated polyester can be obtained safely and efficiently.

That is, the ratio of maleic anhydride (A) to water (B) used in the first step is as follows: maleic anhydride (A) is A mole and water (B) is B mole. 0 ≧
B / A ≧ 0.2. When the above molar ratio (B / A) is 1.0
When the ratio exceeds the above range, the viscosity of the obtained dicyclopentadiene-modified unsaturated polyester becomes high, the handleability decreases, and the hot water resistance of a molded article using the unsaturated polyester deteriorates. This is because when water (B) exceeding the theoretical equivalent to maleic anhydride (A) is used, a side reaction occurs in the first step, and this side reaction component is a factor that lowers hot water resistance. That is the reason.

When the amount of water (B) added exceeds the theoretical equivalent to maleic anhydride (A), the reaction mixture of maleic anhydride (A) and water (B) is In a non-uniform suspension. The solid portion thus generated may cause a problem that the reactant outlet provided in the reaction container is clogged or adheres to a thermometer of the reaction container to cause a state in which an accurate temperature is not displayed. . Furthermore, when the amount of water (B) used increases, the amount of the solid portion deposited increases, so that stirring cannot be performed sufficiently, and the operation of the production apparatus that advances the reaction system cannot be performed safely. The problem arises.

On the other hand, when the molar ratio (B / A) is less than 0.2, the content of dicyclopentenyl groups, which are dicyclopentadiene residues, in the dicyclopentadiene-modified unsaturated polyester decreases, and The viscosity of the obtained dicyclopentadiene-modified unsaturated polyester increases, and the handleability deteriorates.

Therefore, in order to exhibit excellent hot water resistance ,
In addition, in consideration of safety in production, in order to suppress precipitation of solids in the reaction system as much as possible, the molar ratio (B / A) of water (B) and maleic anhydride (A) is 1.0> B
/ A is preferred, and more preferably 0.9 ≧ B / A. Further, in order to maintain the low viscosity, which is a feature of the unsaturated polyester modified with dicyclopentadiene, it is necessary to ensure the amount of maleic acid that reacts with dicyclopentadiene, so that 0.2 ≦ B / A. . From the above, the molar ratio (B / A) is most preferably 0.2 ≦ B / A ≦ 0.9 in order to achieve the above effects together.

The reaction between maleic anhydride (A) and water (B) is carried out at a temperature of 100 ° C. or more and 140 ° C. or less, preferably 120 ° C. or more and 130 ° C. or less, in order to suppress precipitation of a solid portion. desirable. If the temperature is lower than 100 ° C., the amount of the solid portion deposited is unfavorably increased, and if the temperature exceeds 140 ° C., maleic acid is rearranged and fumaric acid having poor solubility is easily produced. It is not preferable because the amount of the precipitated solid (converted) portion increases.

Since the reaction between maleic anhydride (A) and water (B) is fast, if the total amount of maleic anhydride (A) and water (B) is mixed and the temperature falls within the above temperature range, Dicyclopentadiene can be introduced.

The method of reacting maleic anhydride (A) with water (B) includes: 1) charging maleic anhydride (A) and water (B) and heating; 2) heating water (B); To this, maleic anhydride (A) is added. 3) Heating maleic anhydride (A) and adding water (B) to it, any method is possible, but it is easy to control exothermic reaction, And, in order to suppress solid matter precipitation, maleic anhydride (A) is heated from 120 ° C to 130 ° C,
It is desirable to use a method in which water (B) is dropped.

Further, a part of the maleic anhydride (A) is
Can be replaced by maleic acid. In this case, the maleic acid to be replaced is preferably equal to or less than the mole of the maleic anhydride (A). If the amount of maleic acid to be replaced exceeds the same mole, the reaction mixture of maleic anhydride (A), maleic acid and water (B) is not preferable because it becomes a heterogeneous state containing solids.

The reaction between the reaction mixture of maleic anhydride (A) and water (B) with dicyclopentadiene (C) is carried out at a temperature of 100 ° C. or more and 140 ° C.
Below, it is desirable to carry out at preferably 120 ° C. or more and 130 ° C. or less. If the temperature is lower than 100 ° C., the amount of the solid portion deposited becomes large, and the reaction in a uniform reaction system cannot be performed. Therefore, if the temperature exceeds 140 ° C., maleic acid is rearranged and fumaric acid having poor solubility is obtained. It is not preferable because the solids likely to precipitate are likely to precipitate, so that the amount of the solids to be deposited is also increased, and dicyclopentadiene (C) is easily decomposed into cyclopentadiene, which lowers the production efficiency of the target substance. .

The amount of dicyclopentadiene (C) used is
When only maleic anhydride (A) is used as a raw material of maleic acid, molar amount of dicyclopentadiene (C) ≤ molar amount of water (B) When a part of maleic anhydride (A) is replaced with maleic acid And the molar amount of dicyclopentadiene (C) ≦ (the molar amount of water (B) + the molar amount of maleic acid).

Further, the content of the dicyclopentadiene group represented by the following general formula (2), which is a dicyclopentadiene residue in the obtained dicyclopentadiene-modified unsaturated polyester, is at least 20% by weight: It is preferable to use dicyclopentadiene (C) in an amount of 51% by weight or less.

[0048]

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(Calculation method of dicyclopentenyl group content)
The reaction between maleic anhydride (A) and water (B) having a theoretical equivalent or less than the above maleic anhydride (A) produces maleic acid equivalent to water (B) and dicyclopentadiene (C). And maleic acid [maleic anhydride (A) and water (B)
And the equivalent of carboxyl groups derived from maleic acid and dicyclopentadiene (C) is added to dicyclopentadiene (C) to form an ester bond. The remaining amount of carboxyl groups after completion is calculated.

The amount of carboxyl groups remaining after the first step calculated by this calculation and the amount of maleic anhydride (A) remaining in the first step (the molar amount of maleic anhydride (A) used in the first step) Amount minus the amount of water (B)));
100% of polybasic acid and polyhydric alcohol to be added in the second step
%, The weight of the condensed water produced in the second step is calculated.

The weight obtained by subtracting the weight of the condensed water obtained by the above calculation from the weight of the raw materials used in the first step and the second step is defined as the theoretical yield of the dicyclopentadiene-modified unsaturated polyester.

The theoretical yield of dicyclopentadiene-modified unsaturated polyester shown above was obtained by multiplying the number of moles of dicyclopentadiene (C) used by 133, which is the molecular weight of dicyclopentenyl group, to obtain the weight of dicyclopentenyl group. Is used to calculate the content of the dicyclopentenyl group.

When the molar amount of dicyclopentadiene (C) used is larger than the molar amount of water (B) (when maleic acid is used in combination, the total molar amount of water (B) and maleic acid)
The hot water resistance of the molded article obtained by using the obtained dicyclopentadiene-modified unsaturated polyester is inferior. When the content of dicyclopentenyl group contained in the obtained dicyclopentadiene-modified unsaturated polyester is less than 20% by weight, dicyclopentadiene (C) is used. The viscosity increases and the handleability decreases.

The end of the first step is determined by measuring the acid value of the reaction mixture and determining the amount of the remaining carboxyl groups.
That is, the completion of the first step is determined based on the fact that the carboxyl groups corresponding to the molar amount of dicyclopentadiene (C) used participate in the addition reaction, and the addition reaction rate can be set to 90 mol% or more. desirable.

The second step is a step of adding a polyhydric alcohol, or a polyhydric alcohol and a polybasic acid to the reaction mixture of the first step to esterify the mixture. The esterification is carried out until the acid value becomes 50 or less while taking out the condensed water generated within the range, thereby obtaining a dicyclopentadiene-modified unsaturated polyester.

The amount of the polyhydric alcohol used in the second step, or the amount of the polyhydric alcohol and the polybasic acid, can be any amount depending on the desired viscosity of the resulting dicyclopentadiene-modified unsaturated polyester. For example, the amount of the carboxyl group (including unreacted maleic anhydride (A)) contained in the reaction mixture in the first step and the amount of the carboxyl group of the polybasic acid charged in the second step are equivalent to the amount of the hydroxyl group. Polyhydric alcohols can be used. In particular, in order to obtain a dicyclopentadiene-modified unsaturated polyester having a low viscosity and excellent hot water resistance, it is advantageous to increase the content of the dicyclopentenyl group. It is preferable to reduce the amount so that the dicyclopentenyl group content is at least 20% by weight.

The polyhydric alcohol used in the second step includes ethylene glycol, diethylene glycol,
1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, dipropylene glycol, 1,5-pentanediol, 1,6-hexanediol, 2,2-dimethyl-1,3-
Propanediol, 2-ethyl-1,4-butanediol, 1,
7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,4-cyclohexanediol, 1,4-dimethylolcyclohexane, 2,2-diethyl-1,3 -Propanediol, 3-methyl-1,4-pentanediol, 2,2-diethyl-1,3-butanediol, 4,5-
Nonanediol, triethylene glycol, tetraethylene glycol, glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol,
Hydrogenated bisphenol A, an alkylene oxide adduct of hydrogenated bisphenol A, an alkylene oxide adduct of bisphenol A, and the like, and an epoxy compound which is a precursor of a polyhydric alcohol may be used as the polyhydric alcohol, for example, ethylene oxide. , Propylene oxide, styrene oxide, glycidyl (meth) acrylate, allyl glycidyl ether, and the like,
These can be used alone or in combination of two or more.

Examples of the above polybasic acids include unsaturated polybasic acids such as maleic acid, fumaric acid, aconitic acid, and itaconic acid, malonic acid, succinic acid, methylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3 -Dimethylsuccinic acid, hexylsuccinic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 3,3-diethylglutaric acid, adipic acid , Pimelic acid, speric acid, azelaic acid, sebacic acid and other aliphatic saturated polybasic acids, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, aromatic saturation such as 2,6-naphthalenedicarboxylic acid Polybasic acid, nadic acid,
1,2-hexahydrophthalic acid, tetrahydrophthalic acid, 1,
Examples thereof include alicyclic saturated polybasic acids such as 4-cyclohexanedicarboxylic acid and anhydrides of these acids, and these can be used alone or in combination of two or more.

In both the first step and the second step, it is desirable to carry out the reaction in the presence of an inert gas such as nitrogen gas in order to suppress coloring of the reactant.
Alternatively, it can be carried out under a pressure that exceeds 1 atm.

The dicyclopentadiene-modified unsaturated polyester produced through the first step and the second step of the present invention is cured by mixing a curing agent and an accelerator described below to obtain a molded article or a coating film. It is possible to mix the radical polymerizable monomer and the polymerization inhibitor to adjust the viscosity and the curing time suitable for the molding operation, usually to obtain a dicyclopentadiene-modified unsaturated polyester resin composition. Used.

As the radical polymerizable monomer, those known for unsaturated polyesters and epoxy (meth) acrylates can be used. For example, styrene, vinyltoluene, pt-butylstyrene, α-methylstyrene, p-methylstyrene, Styrene monomers such as chlorostyrene, p-methylstyrene, p-chloromethylstyrene, divinylbenzene, (meth) acrylic acid, methyl (meth) acrylate, (meth)
Ethyl acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth)
2-hydroxyethyl acrylate, 2- (meth) acrylate
Hydroxypropyl, glycidyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, esterified product of alkylene oxide adduct of bisphenol A with (meth) acrylic acid, trimethylolpropane tri (meth) acrylate (Meth) acrylic acid-based monomers such as trimethylolethanetri (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, diallyl phthalate, diallyl Allyl ester monomers such as isophthalate can be mentioned, and these can be used alone or in combination of two or more.

The radical polymerizable monomer is used in an amount of 2 to 3 parts by weight based on 100 parts by weight of the dicyclopentadiene-modified unsaturated polyester.
It is used in the range of 00 parts by weight.

As the polymerization inhibitor, those known for unsaturated polyesters and epoxy (meth) acrylates can be used. Examples thereof include phenothiazines such as phenothiazine and methoxyphenothiazine, hydroquinone, methylhydroquinone, trimethylhydroquinone, and mono-t-hydroquinone. Hydroquinones such as -butylhydroquinone and pt-butylcatechol; phenols such as methoxyphenol, butylated hydroxytoluene and phenol; quinones such as benzoquinone and naphthoquinone; nitro compounds such as nitrophenol; benzyltriethylammonium chloride; Organic onium halides such as phenylphosphonium chloride and trimethylsulfonium iodide, triphenylphosphite, monophenylphosphite Organic phosphite esters may be mentioned the like, they may be used in combination either alone, or two or more.

As the curing agent, accelerator, and accelerator, there may be used those known for unsaturated polyester resins and epoxy (meth) acrylate resins (also called vinyl ester resins).

Examples of the curing agent include ketone peroxides such as methyl ethyl ketone peroxide and acetylacetone peroxide, hydroperoxides such as cumene hydroperoxide, diacyl peroxides such as benzoyl peroxide, dicumyl peroxide, and t-butyl. Dialkyl peroxides such as cumyl peroxide; alkyl peresters such as t-butylperoxy-2-ethylhexanoate and t-butylperoxybenzoate; and peralkyls such as bis (4-t-butylcyclohexyl) peroxydicarbonate. Azo compounds such as carbonate, 2,2′-azobisisobutyronitrile, and 2,2′-azobis-2-methylbutyronitrile, and these may be used alone or in combination of two or more. Can be.

Examples of the accelerator include metal soaps such as cobalt octylate and manganese octylate, metal chelate compounds such as cobalt acetylacetonate and vanadium acetylacetonate, and amine compounds such as dimethylaniline. Or a combination of two or more.

The promoting aid enhances the efficacy of the promoting agent, for example, acetylacetone, ethyl acetoacetate,
Examples include acetoacetic anilide, and these can be used alone or in combination of two or more.

According to the present invention, the dicyclopentadiene-modified unsaturated polyester produced and the resin composition using the above unsaturated polyester can be used as a fiber reinforced plastic, paint, casting, resin concrete, lining, sheet molding molding material ( It can be used for various applications such as SMC), bulk molding molding material (BMC), etc., and may be mixed with thixotropic agents, fillers, drying improvers, thickeners, low shrinkage agents, etc. as necessary. Can be.
Further, another type of thermosetting resin may be mixed.

Examples of the thixotropic agent include anhydrous fine powder silica, asbestos, clay and the like, and examples of the filler include aluminum hydroxide, talc, silica sand, crushed stone, calcium carbonate, antimony oxide and the like. Examples of the drying improver include paraffin and drying oil.

Examples of the thickener include metal oxides such as magnesium oxide, calcium oxide and zinc oxide, and polyisocyanate compounds such as tolylene diisocyanate, meta-xylylene diisocyanate and diphenylmethane diisocyanate. Examples thereof include thermoplastic polymers such as polyvinyl acetate, polystyrene, polyester, and polymethyl methacrylate.

Examples of other types of thermosetting resins include, for example, other unsaturated polyesters different from dicyclopentadiene-modified unsaturated polyesters, epoxy (meth) acrylates, urethane (meth) acrylates, polyester (meth) acrylates, polyols (Meth) acrylate and the like. When used for a fiber-reinforced plastic material, inorganic fibers such as glass fibers and carbon fibers, polyester fibers, and organic fibers such as polyamide fibers made of linear aliphatic polyamide or wholly aromatic polyamide can be used.

[0072]

EXAMPLES Examples of the present invention and comparative examples for supporting the present invention will be described below. [Example 1] First, a method for measuring an acid value for judging the end of the reaction in the method for producing an unsaturated polyester of the present invention will be described. The acid value is determined by the water required to neutralize 1 g of a sample. The titration solution was expressed in mg of potassium oxide, and a 0.1 N aqueous potassium hydroxide solution was used.

Next, a method for measuring boiling resistance indicating hot water resistance for each molded article formed using the unsaturated polyester obtained in the present example and the comparative example will be described. The boiling resistance was evaluated by immersing a test piece prepared by the following method in boiling water, observing the appearance of the test piece with time, and evaluating the time until cracks occurred in the test piece. Things.

The method of manufacturing the test piece is as follows. First, 0.6 g of cobalt octylate of 8% by weight of metal and 3.0 g of a 55% pure methyl ethyl ketone peroxide solution were added to 300 g of each of the resins obtained in this example and this comparative example, and the mixture was cast in glass. Pour into the mold,
Left overnight. The next day, after heating at 110 ° C. for 2 hours, it was removed from the mold to obtain a cured product having a size of 3 mm × 300 mm × 270 mm. This cured product was cut into a piece of 3 mm × 75 mm × 25 mm to obtain a test piece.

Next, the method for producing the unsaturated polyester of Example 1 will be described. First, maleic anhydride is placed in a reaction vessel equipped with a reflux condenser, a nitrogen inlet, a stirrer, a thermometer, and a dropping device. (A) 490 g (5 mol) and 580 g (5 mol) of maleic acid were charged and heated to 120 ° C., and 72 g (4 mol) of water (B) was dropped from the dropping device over 10 minutes. The temperature of the contents during the dropping is increased from 120 ° C. to 13
When the temperature was kept within the range of 0 ° C., the content was a homogeneous liquid without any solid matter.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 1251 g (9 mol) of 95% pure dicyclopentadiene (C) was added from the dropping device to
It was dropped over time. After completion of the dropwise addition, the temperature is further increased to 30
Heating was continued for 1 minute to obtain a reaction mixture having an acid value of 264 (addition reaction rate: 97 mol%) (first step).

To this reaction mixture, 372 g (6 mol) of ethylene glycol was added, and esterification was carried out while heating at 200 ° C. to remove water distilled off. When the acid value reached 25, the mixture was cooled to 120 ° C and 2570 g
The dicyclopentadiene-modified unsaturated polyester (dicyclopentenyl group content: 46% by weight) was obtained (second step).

860 g of styrene and 0.7 g of hydroquinone were mixed with this unsaturated polyester to obtain a dicyclopentadiene-modified unsaturated polyester resin composition having a styrene content of 25% by weight and a viscosity of 2.5 Stokes.

Example 2 980 g (10 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1 above, heated to 120 ° C., and 162 g (9 mol) of water (B).
Was dropped from the dropping device in 10 minutes. When the temperature of the contents during the dripping was kept in the range of 120 ° C to 130 ° C,
The contents were a homogeneous liquid with no solids.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 1251 g (9 mol) of 95% pure dicyclopentadiene (C) was added from the dropping device to
It was dropped over time. After completion of the dropwise addition, the temperature is further increased to 30 at 125 ° C.
Heating was continued for a minute to obtain a reaction mixture having an acid value of 266 (addition reaction rate: 96 mol%).

The reaction mixture was treated in the same manner as in Example 1 to obtain a styrene content of 25% by weight and a viscosity of 2.5.
A Stokes dicyclopentadiene-modified unsaturated polyester resin composition was obtained.

Comparative Example 1 The same operation as in Example 2 was conducted except that 180 g (10 mol) of water (B) was used instead of 162 g (9 mol) of water (B) in Example 2 above. Thus, a dicyclopentadiene-modified unsaturated polyester resin composition having a styrene content of 25% by weight and a viscosity of 2.5 Stokes was obtained.

Comparative Example 2 980 g (10 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1, heated to 120 ° C., and 198 g (11 mol) of water (B) was added dropwise. 10 from the device
In minutes. When the temperature of the content during dropping was kept in the range of 120 ° C to 130 ° C, the content was a heterogeneous suspension containing solids.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 1251 g (9 mol) of 95% pure dicyclopentadiene (C) was added from the dropping device to
It was dropped over time. After completion of the dropwise addition, the temperature is further increased to 30 at 125 ° C.
Heating was continued for a minute to reach an acid value of 280 (addition reaction rate: 88 mol%). Further, heating was continued for 1 hour to obtain an acid value of 27.
A reaction mixture of 5 (addition reaction rate 90 mol%) was obtained.

The reaction mixture was operated in the same manner as in Example 1 to obtain a styrene content of 25% by weight and a viscosity of 2.8.
A Stokes dicyclopentadiene-modified unsaturated polyester resin composition was obtained.

Comparative Example 3 980 g (10 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1, heated to 120 ° C., and 252 g (14 mol) of water (B) was added dropwise. 10 from the device
In minutes. When the temperature of the content during dropping was kept in the range of 120 ° C to 130 ° C, the content was a heterogeneous suspension containing solids.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 1251 g (9 mol) of 95% pure dicyclopentadiene (C) was added from the dropping device to
It was dropped over time. After completion of the dropwise addition, the temperature is further increased to 30 at 125 ° C.
The heating was continued for a minute, and the acid value reached 303 (addition reaction rate: 73 mol%). Further, heating was continued for 1 hour to obtain an acid value of 26.
7 (75 mol% of ester by addition reaction) was obtained.

The reaction mixture was treated in the same manner as in Example 1 to obtain a styrene content of 25% by weight and a viscosity of 5.0.
A Stokes dicyclopentadiene-modified unsaturated polyester resin composition was obtained.

Each of Examples 1 and 2 and Comparative Examples 1 and 2
The appearance of the resin composition produced in each of Examples 2 and 3 was visually evaluated at the time of production, and the physical properties (hot water resistance) of each molded article produced by curing each of the resin compositions were evaluated. The results are shown in Table 1. Table 1 also shows the ratio of maleic anhydride (A) to water (B) used in the production, the state of the reaction mixture before dicyclopentadiene (C) was charged, and the boiling resistance of the obtained resin. 1 is shown.

As is clear from the results in Table 1, the water (B) used was based on the molar amount of maleic anhydride (A) used.
By setting the molar ratio (B / A) to 1 or less, precipitation of solids in the reaction mixture before the introduction of dicyclopentadiene is suppressed, and the resulting unsaturated polyester has a low viscosity. Further, it can be seen that the molded article obtained from the resin composition using the unsaturated polyester has excellent boiling water resistance, which is hot water resistance.

[0091]

[Table 1]

Example 3 588 g (6 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1, heated to 120 ° C., and 72 g (4 mol) of water (B) was added dropwise. It was dropped from the device in 10 minutes. The temperature of the contents during the dropping is increased from 120 ° C. to 13
When the temperature was kept within the range of 0 ° C., the content was a homogeneous liquid without any solid matter.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 556 g (4 mol) of 95% pure dicyclopentadiene (C) was dropped from the dropping device over 2 hours. After completion of the dropwise addition, heating was further continued at 125 ° C. for 30 minutes to obtain an acid value of 378 (addition reaction rate: 95 mol%).
Was obtained.

The reaction mixture was mixed with isophthalic acid 16
6 g (1 mol) and 380 g (5 mol) of propylene glycol were added, and esterification was performed while heating to 200 ° C. to remove water distilled off. When the acid value reached 20, the mixture was cooled to 120 ° C. to obtain 1600 g of a dicyclopentadiene-modified unsaturated polyester (dicyclopentenyl group content: 33% by weight).

860 g of styrene and 0.5 g of hydroquinone were mixed with this unsaturated polyester to obtain a dicyclopentadiene-modified unsaturated polyester resin composition having a styrene content of 35% by weight and a viscosity of 3.0 Stokes.

Example 4 588 g (6 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1, heated to 120 ° C., and 36 g (2 mol) of water (B) was added dropwise. It was dropped from the device in 10 minutes. The temperature of the contents during the dropping is increased from 120 ° C. to 13
When the temperature was kept within the range of 0 ° C., the content was a homogeneous liquid without any solid matter.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 278 g (2 mol) of 95% pure dicyclopentadiene (C) was dropped from the dropping apparatus over 1 hour. After completion of the dropwise addition, heating was further continued at 125 ° C. for 30 minutes to obtain an acid value of 625 (addition reaction rate: 98 mol%).
Was obtained.

The reaction mixture was treated with isophthalic acid 24
9 g (1.5 mol), 509 g of propylene glycol
(6.7 mol), and the mixture was heated to 200 ° C. to remove water distilled off, and esterification was performed. When the acid value reached 20, the mixture was cooled to 120 ° C. to obtain 1460 g of a dicyclopentadiene-modified unsaturated polyester (dicyclopentenyl group content: 18% by weight).

To this unsaturated polyester, 790 g of styrene and 0.5 g of hydroquinone were mixed to obtain a dicyclopentadiene-modified unsaturated polyester resin composition having a styrene content of 35% by weight and a viscosity of 6.0 Stokes.

Comparative Example 4 588 g (6 mol) of maleic anhydride (A) was charged into the reaction vessel described in Example 1, heated to 120 ° C., and 126 g (7 mol) of water (B) was added dropwise. It was dropped from the device in 10 minutes. The temperature of the contents during dripping is increased from 120 ° C to 1
When kept in the range of 30 ° C., the contents were a heterogeneous suspension containing solids.

Subsequently, the temperature of the contents was raised from 120 ° C. to 13
While maintaining the temperature within the range of 0 ° C., 556 g (4 mol) of 95% pure dicyclopentadiene (C) was dropped from the dropping apparatus over 1 hour. After completion of the dropwise addition, heating was further continued at 125 ° C. for 30 minutes to obtain an acid value of 362 (addition reaction rate: 95 mol%).
Was obtained.

To the reaction mixture, isophthalic acid 16
6 g (1 mol) and 380 g (5 mol) of propylene glycol were added, and esterification was performed while heating to 200 ° C. to remove water distilled off. When the acid value reached 20, the mixture was cooled to 120 ° C. to obtain 1600 g of a dicyclopentadiene-modified unsaturated polyester (dicyclopentenyl group content: 33% by weight).

860 g of styrene and 0.5 g of hydroquinone were mixed with the unsaturated polyester to obtain a dicyclopentadiene-modified unsaturated polyester resin composition having a styrene content of 35% and a viscosity of 3.2 Stokes.

The resin compositions produced in Examples 3 and 4 and Comparative Example 4 were visually observed during the production, and the physical properties (heat-resistant water resistance) of each molded article produced by curing each of the resin compositions. ) Were evaluated. Table 2 shows the results. Table 1 shows the ratio of maleic anhydride (A) and water (B) used in the production, and dicyclopentadiene (C).
The state of the reaction mixture before charging and the boiling resistance of the obtained resin are also shown in Table 2.

As is evident from the results in Table 2, the water (B) used was based on the molar amount of maleic anhydride (A) used.
By setting the molar ratio (B / A) to 1 or less and 0.2 or more, the precipitation of solids in the reaction mixture before the introduction of dicyclopentadiene is suppressed, and the above Example 4 is used. It can be seen that the molded article produced from the resin composition using the unsaturated polyester obtained in and 5 has excellent hot water resistance and boiling resistance.

[0106]

[Table 2]

[0107]

As described above, the method for producing an unsaturated polyester according to the present invention comprises the steps of preparing maleic anhydride (A) and water (B).
And reacted at 120 ° C or higher and 130 ° C or lower,
A first step of reacting the obtained reaction mixture with dicyclopentadiene (C); and reacting the reaction mixture of the first step with a polyhydric alcohol or a polyhydric alcohol and a polybasic acid to obtain dicyclopentadiene. A second step of obtaining an unsaturated polyester modified by (C), wherein the molar ratio (B / A) of water (B) and maleic anhydride (A) used in the first step is 1 It is a method of setting to less than .

[0108] Therefore, the above-mentioned method is characterized in that the molar ratio (B / A) of water (B) and maleic anhydride (A) is set to less than 1 so that the reaction mixtures obtained in the first step can be mixed with each other. It can be a dissolved homogeneous system.

From the above, the runaway reaction exotherm in the first step of adding dicyclopentadiene (C) to the reaction mixture and the formation of by-products which are liable to occur due to the reaction in the heterogeneous system are suppressed by the above-mentioned method. Since it can be suppressed by the homogeneous system and the control of the reaction exotherm can be easily controlled, it is possible to avoid an increase in cost due to an increase in size of the cooling device for reducing the risk due to the reaction exotherm, and furthermore, the generation of the byproduct As a result, deterioration of hot water resistance due to the by-products can be reduced in a molded article using the unsaturated polyester.

As a result, the above method has an effect that the production of unsaturated polyester can be performed more safely while avoiding an increase in cost.

[0111]

[0112]

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 63/00-63/91

Claims (2)

(57) [Claims] 1. A method in which maleic anhydride (A) and water (B) are mixed and reacted at 120 ° C. or more and 130 ° C. or less, and then the resulting reaction mixture is reacted with dicyclopentadiene (C). One step and a second step of reacting the reaction mixture of the first step with a polyhydric alcohol or a polyhydric alcohol and a polybasic acid to obtain an unsaturated polyester modified with dicyclopentadiene (C). A method for producing an unsaturated polyester, wherein the molar ratio (B / A) of water (B) and maleic anhydride (A) used in the first step is less than 1. 2. The unsaturated polyester has a dicyclopentenyl group derived from dicyclopentadiene (C) in an amount of 20%.
The method for producing an unsaturated polyester according to claim 1, wherein the content of the unsaturated polyester is at least 10% by weight.