JPH06843B2 - Unsaturated polyester resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an unsaturated polyester resin obtained by blending a polymerizable monomer with a special unsaturated polyester, which reduces the volatilization amount of the polymerizable monomer and has a good stacking workability. Is good
It is intended to provide an unsaturated polyester resin for lamination, which imparts water resistance and gel coat blister resistance to a molded article.

A reinforced plastic having an unsaturated polyester resin as a matrix and a glass fiber as a reinforcing material has many applications for products around water such as ships, bathtubs, pools, water tanks, and septic tanks. In many cases, these products use Handley up method or spray up method for molding.
The unsaturated polyester resin used for laminating these molded products has 1) less volatilization of the polymerizable monomer from the viewpoint of improving the working environment, and 2) shortening the laminating time.
Good impregnation and compatibility with the glass mat and unsaturated polyester resin, 3) good water resistance of the resulting laminate and good blister resistance of the gel coat layer, 4) cheap resin, etc. Characteristics are required.

In an ordinary unsaturated polyester resin obtained by dissolving an unsaturated polyester obtained by reacting a polyhydric alcohol, an α, β-unsaturated dibasic acid and a saturated dibasic acid in a polymerizable monomer, these requirements are required. It is extremely difficult to satisfy all the characteristics.

For example, when isophthalic acid or terephthalic acid, which is an aromatic dibasic acid, is used as the saturated dibasic acid component, the water resistance of the laminated product or the blister resistance of the gel coat layer is improved, and the glass mat and the unsaturated polyester resin are combined. Although the impregnating property and the compatibility can be improved, since the content of the polymerizable monomer increases, the volatilization amount also increases and the working environment deteriorates, and at the same time, the price also increases.

Further, if the content of the polymerizable monomer is reduced to improve the volatilization amount thereof, the viscosity of the unsaturated polyester resin is increased and impregnation into the glass mat is deteriorated, resulting in poor conformability.

In order to reduce the viscosity of the unsaturated polyester resin, if the unsaturated polyester is made to have a low molecular weight and the amount of the polymerizable monomer is reduced, the volatilization amount of the polymerizable monomer and the impregnation property into the glass mat are improved. Reduce the water resistance of the laminated product and the blister resistance of the gel coat layer.

In view of such circumstances, the present inventor has conducted diligent studies using a relatively inexpensive dicyclopentadiene as a raw material as a component of an unsaturated polyester, and as a result, compares favorably with an ordinary unsaturated polyester resin. To find an unsaturated polyester resin composition having impregnability into a glass mat and compatibility with it, water resistance of a laminated product and blistering of a gel coat layer are comparable, and less volatilization of a polymerizable monomer It has come.

That is, the present invention comprises: (a) reacting a saturated dibasic acid containing at least 50 mol% of an aromatic dibasic acid with a polyhydric alcohol or an alkylene oxide until the reaction rate of all carboxyl groups is 75% or more. The resulting ester compound having a hydroxyl group at the terminal, maleic anhydride, and dicyclopentadiene are mixed in a ratio such that the hydroxyl group becomes an excess equivalent to the carboxyl group, and the mixture is reacted at 145 ° C. or lower, followed by heating. And an unsaturated polyester resin composition obtained by carrying out a polycondensation reaction, which comprises 55 to 80% by weight of an unsaturated polyester having an acid value of 40 or less and (b) 45 to 20% by weight of a polymerizable monomer. .

Examples of the aromatic dibasic acid constituting the saturated dibasic acid used in the present invention include terephthalic acid, isophthalic acid,
Examples thereof include phthalic acid and phthalic anhydride. Other dibasic acids include aliphatic dibasic acids represented by succinic acid, adipic acid, and sebacic acid; tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride. Examples thereof include alicyclic dibasic acids represented by acids, and examples of polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, and 1,4-butane. Diol, 1,6-hexanediol, 2,2,4-
Examples include trimethyl-1,3-pentanediol, neopentyl glycol, alkylene oxide adducts of bisphenol A, and the like, and examples of alkylene oxides include ethylene oxide and pyropyrene oxide.

The ester compound used in the present invention is a saturated dibasic acid containing the aromatic dibasic acid in a proportion of at least 50 mol%, and the polyhydric alcohol and / or the alkylene oxide at the terminal of the ester compound. It is synthesized by adding a proportion having a hydroxyl group and / or polycondensing it.

Furthermore, this alkylene oxide may be used in a mode in which it is reacted with a monoester produced by the reaction of a saturated dibasic acid and a polyhydric alcohol.

The polycondensation reaction of a saturated dibasic acid and a polyhydric alcohol, the conditions of the reaction of the first step in the production of unsaturated polyester by a normal two-step reaction can be applied as it is, specifically, the raw material mixture in the presence of a catalyst or In the absence, 150-22
This is achieved by heating at 0 ° C and polycondensation.

In addition, the reaction of a monoester obtained by the reaction of a saturated dibasic acid with an alkylene oxide or the reaction of a saturated dibasic acid with a polyhydric alcohol and an alkylene oxide is carried out in the presence or absence of a catalyst at 150 to It is carried out at a temperature of 250 ° C., for example, one example of this method is disclosed in JP-A-55-155022.

The ester compound thus obtained contains a monomeric compound in which a polyhydric alcohol or an alkylene oxide is added to both carboxyl groups of a saturated dibasic acid, and an oligomer having a repeating ester bond as a structural unit in the polymer chain is formed. Comprehensive. This ester compound does not matter even if it contains unreacted polyhydric alcohol.

The saturated dibasic acid component constituting the present ester compound must contain at least 50 mol% of an aromatic dibasic acid, and when an ester compound consisting of less than that component is used, the object of the present invention is Which deteriorates the water resistance of the laminate and the blister resistance of the gel coat layer, and also increases the price. Both ends of this ester compound do not necessarily have to be 100% hydroxyl groups, but at least 75% of all carboxyl groups of the saturated dibasic acid must be an ester compound obtained by reacting with a polyhydric alcohol and / or alkylene oxide. I won't.

An unsaturated polyester resin obtained by using an ester compound having a carboxyl group reaction rate of less than 75% cannot satisfy the water resistance of a laminate and the blister resistance of a gel coat layer.

In order to produce the unsaturated polyester used in the present invention, the above ester compound, maleic anhydride and dicyclopentadiene are first reacted together at a reaction temperature of 145 ° C. or lower until there is no unreacted dicyclopentadiene. The maleic anhydride is used in such a ratio that the hydroxyl group becomes an excess equivalent to the carboxyl group in the product.

When reacted at a temperature higher than 145 ° C, dicyclopentadiene preferentially decomposes to form cyclopentadiene, which cyclopentadiene reacts with maleic acid and Diels-Ald.
er reaction to eliminate the double bond of maleic acid, and as a result, the resulting reaction product cannot volatilize its original performance as an unsaturated polyester.

Then, the temperature of the product obtained in the above reaction is raised, and the polycondensation reaction is performed by directly applying the well-known ordinary unsaturated polyester production conditions. For example, the acid of the reaction product is heated at a temperature of 180 to 230 ° C. The desired unsaturated polyester is obtained by performing an esterification reaction until the value becomes 40 or less.

If it is difficult to reduce the acid value of the unsaturated polyester to 40 or less, even if a polyhydric alcohol is added to the ester compound or a polyhydric alcohol or an alkylene oxide is added at the stage of the esterification reaction. If the acid value of the unsaturated polyester is higher than 40, it is not preferable because the water resistance of the laminate and the blister resistance of the gel coat layer are adversely affected.

By dissolving the unsaturated polyester produced in this manner in a polymerizable monomer containing an inhibitor, the unsaturated polyester resin composition of the present invention is obtained, the unsaturated polyester resin composition Include unsaturated polyester 55 to 50% by weight and polymerizable monomer 20 to 45
Wt% is contained.

Examples of the polymerizable monomer used here include styrene and α
-Vinyl aromatic compounds exemplified by methylstyrene, chlorostyrene, pt-butylstyrene, vinyltoluene, p-methylstyrene and divinylbenzene; allyl compounds exemplified by diallyl phthalate and triallyl cyanurate; methyl acrylate , Methyl methacrylate, ethylene glycol, 1,3-butadiol, 1,
Use of an acrylic compound exemplified by di (meth) acrylate or tri (meth) acrylate of a polyhydric alcohol exemplified by 4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, etc. You can

These polymerizable monomers can be used alone or in admixture of two or more.

When the content of the polymerizable monomer in the unsaturated polyester resin composition of the present invention is less than 20% by weight or exceeds 45% by weight, the double bond contained in the unsaturated polyester and the polymerizable monomer may be contained in the unsaturated polyester resin composition. It is not preferable because the chemical equivalent balance with the double bond contained is significantly lost, and the mechanical properties of the laminate, the water resistance and the blister resistance of the gel coat layer are significantly reduced.

As the inhibitor used when dissolving the unsaturated polyester in a predetermined polymerizable monomer, hydroquinone, pt
Known compounds such as -butylcatechol, mono-t-butylhydroquinone, tolhydroquinone, and hydroquinone monomethyl ether can be used.

In curing the unsaturated polyester resin composition of the present invention, benzoyl peroxide, methyl ethyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, t-butyl perbenzoate, cumene hydroperoxide, di-t-butyl peroxide are exemplified. The polymerization initiator used in the usual unsaturated polyester resin is used, and the accelerator is also generally used in the unsaturated polyester resin. Cobalt naphthenate, cobalt octenoate, aliphatic amine, aromatic amine , Acetylacetone, ethyl acetoacetate, etc. may be used alone or in the form of a mixture of two or more.

The unsaturated polyester resin composition of the present invention is usually used as a laminate in combination with a glass fiber reinforcing material such as a glass mat, but may be used alone, of course, and various additives or fillers may be added as desired. You may add and use a material.
It may be used in a desired shape depending on the application. Next, the present invention will be described in detail with reference to Examples and Comparative Examples.

Example 1 Isophthalic acid 996. was added to 6 reactors equipped with a stirrer, a thermometer, a nitrogen gas inlet tube and a partial condenser.
Charge 8 g and propylene glycol 1613.1 g,
Condensation reaction at 190 ° C. for 9.5 hours under nitrogen gas flow,
An ester compound having an acid value of 10.0 was obtained (isophthalic acid conversion rate of about 96%). Maleic anhydride 1372.8
g and 105.7 g of dicyclopentadiene were added, and the mixture was reacted at 140 ° C. for 9 hours under a nitrogen gas stream, then heated to 220 ° C. and reacted for 5 hours to obtain an unsaturated polyester having an acid value of 26. Hereinafter, it is abbreviated as "UP-1A".

Example 2 1680.0 g of the ester compound obtained by the reaction of isophthalic acid and propylene oxide was placed in the same reactor as in Example 1.
(Number average molecular weight 348, hydroxyl value 321, acid value 1), propylene glycol 182.6 g, maleic anhydride 13
72.80 g, and dicyclopentadiene 1057.
After charging 7 g and reacting at 140 ° C. for 5 hours under a nitrogen gas flow, 608.7 g of propylene glycol was added and the temperature was raised to 210 ° C. under a nitrogen gas flow for 4.5 hours to carry out reaction. A saturated polyester was obtained. "U
It is abbreviated as "P-2A".

Example 3 A reactor similar to that of Example 1 was charged with terephthalic acid 1063.2.
g (80 mol%), adipic acid 233.8 g (20 mol%), propylene glycol 1164.2 g and neopentyl glycol 677.0 g were charged, and the mixture was placed under a nitrogen gas stream in the presence of stannous oxalate at 195 ° C. A condensation reaction was carried out for 13 hours to obtain an ester compound having an acid value of 15.8 (reaction rate of dibasic acid: about 95%). Maleic anhydride 11
After adding 76.7 g and dicyclopentadiene 793.3a and reacting at 135 ° C. for 6 hours in a nitrogen gas stream,
The temperature was raised to 210 ° C. and the reaction was carried out for 8 hours to obtain an unsaturated polyester (“UP-3A”) having an acid value of 35.

Example 4 888.7 g of phthalic anhydride was placed in the same reactor as in Example 1.
And 1613.1 g of propylene glycol,
A condensation reaction was carried out at 185 ° C. for 10 hours in a nitrogen gas stream to obtain an ester compound having an acid value of 14.3 (reaction rate of orthophthalic acid: about 95%). Maleic anhydride 1372.8
g and dicyclopentadiene (1057.7 g) were added, and the mixture was reacted at 140 ° C. for 8 hours under a nitrogen gas stream, then heated to 210 ° C. and reacted for 4.5 hours to obtain an unsaturated polyester having an acid value of 30 (“UP- 4A ") was obtained.

Example 5 In the same reactor as in Example 1, the ester compound 1686.0 obtained by the reaction of orthophthalic acid and propylene oxide was used.
g (number average molecular weight 337, hydroxyl value 332, acid value 1),
Propylene glycol 182.6g, maleic anhydride 1
372.8 g and dicyclopentadiene 1057.7
g, and reacted at 140 ° C. for 5 hours in a nitriding gas stream, 721.0 g of 1,3-butanediol was added, and the temperature was continuously raised to 210 ° C. under a nitrogen gas stream for 4.3 hours to react with acid. Unsaturated polyester with a valency of 21 (“UP-5
A ") was obtained.

Comparative Example 1 In a reactor similar to that of Example 1, 996.8 g of isophthalic acid was added.
And propylene glycol 1613.1 g were charged, and the condensation reaction was carried out at 180 ° C. for 4 hours under a nitrogen gas stream to obtain an acid value of 10
9 ester compounds were obtained (the reaction rate of isophthalic acid was about 6
0%).

To this, 1372.8 g of maleic anhydride and 1057.7 g of dicyclopentadiene were added, and after reacting for 9 hours at 140 ° C. in a nitrogen gas stream, the temperature was raised to 220 ° C. and reacted for 5 hours to obtain an unsaturated polyester having an acid value of 27. Got "UP
-1B ".

Comparative Example 2 While maintaining 158 g of water and 784.5 g of maleic anhydride at 140 ° C. under a nitrogen gas stream in the same reactor as in Example 1, 1057.7 g of dicyclopentadiene was added portionwise over 1.5 hours, Further, the reaction was carried out at that temperature for 30 minutes to synthesize dicyclopentadiene monomaleate. 1392 g (number average molecular weight 34) of the ester compound obtained by the reaction of isophthalic acid and propylene oxide was added to this reaction product.
No. 8, hydroxyl value 321, acid value 1) was added, the temperature was raised to 210 ° C. and the esterification reaction was carried out by a conventional method to obtain an unsaturated polyester having an acid value of 21 (“UP-2B”).

Comparative Example 3 531.1 g of terephthalic acid was placed in the same reactor as in Example 1.
(40 mol%), adipic acid 701.5 g (60 mol%), propylene glycol 1164.2 g and neopentyl glycol 677.0 g were charged, and the mixture was made into a nitrogen gas stream in the presence of stannous oxalate at 190 ° C. for 10 hours. A condensation reaction was performed to obtain an ester compound having an acid value of 14.7 (reaction rate of dibasic acid: about 95%). Maleic anhydride 11
76.7 g and dicyclopentadiene 793.3 g were added, and the mixture was reacted under a nitrogen gas stream at 135 ° C. for 6 hours, and then 2
The temperature was raised to 10 ° C. and the reaction was performed for 8 hours to obtain an unsaturated polyester (“UP-3B”) having an acid value of 34.

Comparative Example 4 Isophthalic acid 2375.7 was placed in the same reactor as in Example 1.
g and propylene glycol 2138.1 g were charged, and a condensation reaction was performed at 195 ° C. for 11 hours under a nitrogen gas stream to obtain an ester compound having an acid value of 26. Maleic anhydride 1
147.3 g was added, and the mixture was reacted at 220 ° C. for 10 hours under a nitrogen gas stream to obtain an unsaturated polyester having an acid value of 12 (“UP-
4B ") was obtained.

Comparative Example 5 Phthalic anhydride 1925.4 was placed in the same reactor as in Example 1.
g, 2176.2 g of propylene glycol and 1274.8 g of maleic anhydride were charged, and 2 under a nitrogen gas stream.
The reaction was carried out at 10 ° C. for 8 hours to obtain an unsaturated polyester (“UP-5B”) having an acid value of 36.

Example 6 and Comparative Example 6 The unsaturated polyester “UP-1A” obtained in Examples 1 to 5
To "UP-5A" are dissolved in a styrene monomer and adjusted to have a viscosity of about 200 centipoise (25 ° C). 0.01 wt% of hydroquino is dissolved in each of these mixtures to prepare an unsaturated polyester resin. Obtained. Hereinafter, each unsaturated polyester resin is abbreviated as "UPR-1A" to "UPR-5A".

Similarly, the unsaturated polyester “UP” obtained in Comparative Examples 1 to 5 was used.
-1B "to" UP-5B "are dissolved in a styrene monomer and adjusted to have a viscosity of about 200 centipoise (25 ° C), and 0.01% by weight of hydroquinone is dissolved in each of these mixtures. Saturated polyester resins “UPR-1B” to “UPR-5B” were adjusted.

Table 1 shows the characteristics of the unsaturated polyester resin thus prepared and the laminated product using the same. Each property was measured by the following method.

"Styrene monomer volatilization amount" is 23 ° C, wind speed is 0.05
In a thermostatic chamber maintained at m / sec, the unsaturated polyester resin is placed with a resin thickness of 3 mm and a surface area of 200 cm ² .
Determine the weight after 90 minutes of standing and reduce the weight per unit area (g /
m ² ). The compatibility of the unsaturated polyester resin with the glass mat can be judged by the solubility of the secondary binder of the glass mat with the unsaturated polyester resin. That is, the faster the dissolution rate of the secondary binder, the better the compatibility with the glass mat, so the dissolution rate was investigated.

10 cm (horizontal) x 30 cm (vertical) in an atmosphere of 20 ° C
Glass mat cut into a rectangular shape [Asahi Fiber Glass Co., Ltd., trade name "CM455FAG", 450 g / m
² ] is placed in 3 plies, and the central part is 10 cm (width) x 1
An unsaturated polyester resin is supplied to an area of 5 cm (vertical length) so that the glass content is 33% by weight, and 3
It was impregnated and defoamed in a minute.

Clip the top of the glass mat with a clip and attach it to the bottom with 50
A weight of 0 g was hung, and the measurement start time was set at this time, and the resin-impregnated laminated portion (the center portion of the glass mat 10 cm ×
The time (minutes) until the secondary binder of the glass mat (15 cm) was dissolved by the resin and the glass mat was cut was determined. This "time until the glass mat is cut" corresponds to the dissolution rate of the secondary binder of the glass mat in the resin.

The laminated product was made of an unsaturated polyester resin containing 6% cobalt naphthenate (0.5% by weight) and methyl ethyl ketone peroxide (1.0% by weight), and the glass mat "CM45" described above.
5FAG ”3 plies were impregnated with a glass content of 33% by weight, defoamed, covered on both sides with a polyester film, allowed to stand at 20 ° C. for 16 hours, and then post-cured at 100 ° C. for 2 hours to prepare. This laminated product is 100 ℃
Was immersed in hot water for 100 hours, the bending strength before and after the immersion was measured, and the "boiling strength retention rate of the laminated product" (%) was obtained.

The blister resistance of the gel coat layer is evaluated by preparing a laminate having the gel coat layer, contacting the gel coat surface with hot water (one-side immersion) to generate blisters, and counting the "number of blisters". be able to. On the surface of the mold, 6% cobalt naphthenate 0.
A gel coat resin (manufactured by Nippon Upica Co., Ltd., trade name: Upica 6510 White) containing 5% by weight and 1.0% by weight of methyl ethyl ketone peroxide has a thickness of 0.5 after curing.
It was applied so as to have a thickness of mm and left at 20 ° C. for 24 hours.

On top of that, 3 plies of the glass mat "CM455FAG" was placed, and an unsaturated polyester resin containing 6% cobalt naphthenate 0.5% by weight and methyl ethyl ketone peroxide 1.0% by weight was supplied, and the glass content was 33% by weight. %, The mixture was left to stand at 20 ° C. for 2 hours, and then post-cured at 40 ° C. for 16 hours to obtain a gel-coated laminated product. The gel-coated surface (area: 100 cm ² ) of this laminate was immersed in hot water at 80 ° C. for 125 hours on one side and then taken out, and the “number of blisters” on that surface.
I asked.

As is clear from the results shown in Table 1, "U of Example 6"
All of PR-1A "to" UPR-5A "have excellent balanced properties, while Comparative Example 6
It can be seen that all of "UPR-1B" to "UPR-5B" have defects in some of the characteristics.

 ─────────────────────────────────────────────────── --Continued front page (56) References JP-A-56-133316 (JP, A)

Claims (1)

[Claims] (A) A saturated dibasic acid containing at least 50 mol% of an aromatic dibasic acid and a polyhydric alcohol or an alkylene oxide having a reaction rate of 7 of all carboxyl groups.
The ester compound having a hydroxyl group at the terminal obtained by reacting until 5% or more, maleic anhydride and dicyclopentadiene are mixed in a ratio such that the hydroxyl group becomes an excess equivalent to the carboxyl group, and the mixture is heated at 145 ° C or lower. 55-80% by weight of unsaturated polyester having an acid value of 40 or less, which is obtained by reacting and then raising the temperature to carry out a polycondensation reaction.
And (b) a polymerizable monomer of 45 to 20% by weight, an unsaturated polyester resin composition.