JPS601884B2 - Unsaturated polyester resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an unsaturated polyester resin composition having low shrinkage and excellent impact resistance.

Conventionally, sheet molding compound (hereinafter referred to as SM
Methods for reducing shrinkage have been carried out, such as the method (abbreviated as C), and a common method is to add a thermofusible resin such as polystyrene, polyvinyl acetate, or polymethyl methacrylate.

However, although this method achieves low shrinkage, the impact resistance is significantly reduced. In addition, as a method to improve impact resistance, there is a method of using adipic acid, diethylene glycol, dipropylene glycol, etc. as the acid or glycol component of unsaturated polyester resin, but this method has the disadvantage of decreasing strength. .

A method of adding polybutadiene has also been carried out, but polybutadiene has disadvantages such as poor compatibility with unsaturated polyester resins and reduced strength. Although low shrinkage and impact resistance tend to contradict each other, SMC used for automobile parts, office equipment covers, etc.
is in a situation where it cannot be put to practical use unless it satisfies both characteristics.

Conventionally, a method has been used in which two or more types of unsaturated polyester resins are mixed to reduce shrinkage.

For example, in the method disclosed in Tokukan Sho 49-11618, resins of different polymerizability and reactivity are mixed, but there are significant restrictions on composition, molecular weight, and reactivity. Furthermore, although the method disclosed in JP-A-50-51188 achieves low shrinkage, the impact resistance is significantly reduced. Even with these known methods, low shrinkage and impact resistance cannot be achieved. As a result of intensive studies to improve these drawbacks, the present inventors have developed a highly reactive unsaturated polyester with a molecular weight per double bond of 140 to 300 and a highly reactive unsaturated polyester with a molecular weight per double bond of 400 to 30,000. The present inventors have discovered that an unsaturated polyester resin composition with low shrinkage and excellent strength and impact resistance can be obtained by combining it with a low-reactivity unsaturated polyester modified with dicyclobentadiene, leading to the completion of the present invention. Ta.

That is, in the present invention, the molecular weight per double bond is 140 to 3
10 to 95 parts by weight of an unsaturated polyester having a molecular weight of 400 to 30,000 per double bond, 5 to 9 parts by weight of an unsaturated polyester modified with dicyclobentadiene, and 10 to 95 parts by weight of a copolymerizable monomer. This invention relates to an unsaturated polyester resin composition containing 200 parts by weight, and will be described in detail below.

The materials used for the unsaturated polyester include acids and alcohols that are commonly used for unsaturated polyesters.

As the acid, unsaturated dibasic acids such as maleic anhydride and fumaric acid are used, and if necessary, saturated dibasic acids such as isophthalic acid, terephthalic acid, orthophthalic acid, and tetrachlorophthalic anhydride are used. Alcohol components include ethylene glycol, propylene glycol, neobentyl glycol, dipromoneobentyl glycol, dipropylene glycol, 2,2bis[para(hydroxy-n-propoxy)phenyl]propane, tricyclodecanediol, trimethylolpropane. /gun, polyhydric alcohol such as polyptadiene glycol is used.

If necessary, linseed oil, soybean oil, transesterified oils thereof, fatty acids, etc. are used. The highly reactive unsaturated polyester having a molecular weight per double bond of 140 to 300 used in the present invention can be easily produced by adjusting the proportion of unsaturated dibasic acid used in producing the unsaturated polyester. This highly reactive unsaturated polyester produced may be modified with dicyclobentadiene.

In the present invention, the molecular weight per double bond is 140 to 300.
The unsaturated polyesters also include unsaturated polyesters modified with dicyclobentadiene. Methods for modifying unsaturated polyester with dicyclobentadiene include [1] a one-step synthesis method in which acid, alcohol, and dicyclobentadiene are simultaneously charged and integrated, and modified at the same time, and {2] a method in which acid and alcohol are condensed. There is a two-step synthesis method in which dicyclobentadiene is added and modified during the process.
Either method is possible.

The molecular weight per double bond in the present invention is 400 to 300
00, and unsaturated polyesters modified with dicyclobentadiene are not limited to those in which dicyclobentadiene is contained in the skeleton of the unsaturated polyester; It may be contained in the skeleton of saturated polyester.

In the present invention, it is also possible to use dicyclobentadiene or a material obtained by reacting dicyclobentadiene in advance, such as the following, as a part of the alcohol component.

The reaction temperature when modifying the unsaturated polyester resin with dicyclobentadiene is preferably in the range of 150 to 2300°. The molecular weight per double bond of the present invention is 400 to 300
00 and the amount of dicyclobentadiene used in the unsaturated polyester modified with dicyclobentadiene is not particularly limited. It is preferable to use the range. The amount of dicyclobentadiene added is 0.
If the amount is less than 0.1 mole, the low shrinkage, strength, and impact resistance effects of the present invention will be slightly inferior, and if it exceeds 0.40 mole, the strength will tend to decrease slightly. When this unsaturated polyester modified with dicyclobentadiene is used, the compatibility with the highly reactive unsaturated polyester is improved, and this is thought to be related to the improvement in properties. Furthermore, it is preferable to modify the polyester of the present invention having a molecular weight of 140 to 300 per double bond with dicyclobentadiene, since this improves strength and impact resistance. The molecular weight per double bond is calculated, for example, as follows. In the case of unsaturated polyester consisting of maleic anhydride and propylene glycol,
The molecular weight of maleic anhydride is 98, the molecular weight of propylene glycol is 76, and the total molecular weight of both is 174.
becomes. Molecular weight of water that will be destroyed by condensation 1
Subtracting 8 gives 156, which is the molecular weight per double bond. 0.8 mol of maleic anhydride, 0.8 mol of phthalic anhydride.
In the case of an unsaturated polyester consisting of 2 moles of propylene glycol and 1.0 moles of propylene glycol, similarly (98×0.
8148×0.276×1.018)÷0.8=
208 That is, 208 is calculated as the molecular weight per double bond. The molecular weight per double bond is a calculated molecular weight and differs from the actual molecular weight. Furthermore, in calculations, the excess ratio of glycol is not taken into account, and calculations are made assuming that acid and glycol are equimolar. When modifying an unsaturated polyester with dicyclobentadiene, for example, in the case of the above-mentioned one-step synthesis method, part of the dicyclobentadiene is added to the double bond of the unsaturated polyester. is blended. Depending on the modification method, the proportion of dicyclobentadiene added to the double bonds of the unsaturated polyester and the molecular weight per double bond of the unsaturated polyester modified with dicyclobentadiene vary, but the unsaturated polyester after modification Determined by analysis of the NMR (nuclear magnetic resonance) spectrum. The molecular weight per double bond of unsaturated polyester needs to be in the range of 140 to 300, and the molecular weight per double bond of unsaturated polyester modified with dicyclobentadiene is 400 to 3.
Must be 0000.

If it deviates from this range, a particularly sufficient shrinkage reduction effect will not be exhibited, and impact resistance will also decrease. Highly reactive unsaturated polyesters with excellent unsaturated polyesters with a good balance of low shrinkage and impact resistance have molecular weights per double bond ranging from 140 to 230, modified with dicyclobentadiene. 900 for unsaturated polyester
~5000. Styrene, dipinylbenzene, vinyltoluene, vinyl acetate, methyl methacrylate, ethyl acrylate, ethylene glycol dimethacrylate, etc. are used as the polymerizable monomer, but styrene is mainly used.

The proportions of the two types of unsaturated polyesters and polymerizable monomers are such that the molecular weight per double bond is 140 to 30.
10 to 95 parts by weight of an unsaturated polyester having a molecular weight of 0 to 1, and 5 to 95 parts by weight of an unsaturated polyester having a molecular weight per double bond of 400 to 30,000 and modified with dicyclobentadiene.
It is necessary that the amount of the polymerizable monomer is 10 to 20 parts by weight.

If the amount of unsaturated polyester having a molecular weight of 140 to 300 per double bond is less than 1 part by weight, low shrinkage properties will be reduced, and if it exceeds 95 parts by weight, impact resistance will be reduced. If the molecular weight per double bond is 400 to 30,000 and the unsaturated polyester modified with dicyclobentadiene exceeds 9 parts by weight, the strength will decrease, and if it is less than 5 parts by weight, the low shrinkage will decrease. If the amount of the polymerizable monomer is less than 1 part by weight, low shrinkage properties will decrease, and if it exceeds 20 parts by weight, impact resistance will decrease. The number average molecular weight of the two types of unsaturated polyesters used in the present invention is not particularly limited, but is usually 400 to 60.
Used in the range 00.

In particular, the molecular weight per double bond is 400 to 30,000, and the number average molecular weight of unsaturated polyester modified with dicyclobentadiene is in the relatively low molecular weight range of 400 to 4,000, and it has particularly low shrinkage properties. and impact resistance. The unsaturated polyester resin composition of the present invention may contain a curing organic peroxide, a polymerization inhibitor, a filler, a reinforcing agent, a mold release agent, a coloring agent, a thickener, etc., as necessary.

Examples of curing organic peroxides include t-butyl peroxybenzoate, benzoyl peroxide, dicumyl/gu oxide, cumene hydro/gu oxide, cyclohexanone/f-oxide, and methyl ethyl ketone peroxide.

Examples of polymerization inhibitors include hydroquinone, parabenzoquinone, catechol, and 2,5-diphenyl/grabenzoquinone.

Examples of fillers include calcium carbonate, clay/barium sulfate, and aluminum hydroxide.

Reinforcing agents include roving-like fibers such as glass fibers, vinylon fibers, and carbon fibers, short fibers,
Various processed materials such as woven fabrics, knitted fabrics, threads, and braided fabrics may be used. Examples of mold release agents include zinc stearate and calcium stearate.

As the colorant, all of the inorganic and organic colorants currently used for coloring unsaturated polyester resins can be used. As the thickener, metal oxides such as magnesium oxide and calcium oxide, metal hydroxides such as magnesium hydroxide, organic thickeners using diisocyanates such as diphenylmethane diisocyanate, and combinations thereof can be used. In addition, if necessary, thermoplastic polymers such as polystyrene, polyvinyl acetate, polymethyl methacrylate, and saturated polyester, and thermosetting polymers such as phenol, epoxy, and melamine may be used in combination, and antimony trioxide , hexabromobenzene, chlorinated paraffin, and the like may also be used. The unsaturated polyester resin composition of the present invention is particularly useful in the SMC method, but is equally useful in the bulk molding compound (BMC) method, preform matched metal die molding method, hand molding method, etc. It is also possible to apply to lay-up molding, spray-up molding, resin injection molding, etc.

The unsaturated polyester resin composition of the present invention is useful not only in heat and pressure molding methods, but also in room temperature and normal pressure molding methods without reducing the effects of low shrinkage and impact resistance, and is useful for resin injection molding. It is possible to solve defects such as cracks and warpage of molded products, which frequently occur in molding methods. Examples of the present invention will be described below.

Parts are parts by weight, and percentages (%) are percentages by weight. Example 1 980 molar (10.0 mol) of maleic anhydride and 1064 molar (14.0 mol) of propylene glycol were mixed at room temperature under a nitrogen stream, and after raising the temperature to 150°C, it took 5 hours to reach i50
The temperature was raised from qo to 210 ko0, and dehydration condensation was further carried out for 7 hours to obtain a highly reactive unsaturated polyester with an acid value of 35.

This unsaturated polyester 65 and hydroquinone 0.0
The unsaturated polyester resin UP-1 was obtained by dissolving 35 styrene containing 100 ml of styrene. As a result of analysis, the number average molecular weight of this unsaturated polyester was 3,700, and the molecular weight per double bond was 156. The number average molecular weight was determined by the GPC method using a polystyrene calibration curve. The same applies to the following. Maleic anhydride 196 mm (2.0 mol), phthalic anhydride 1184 mm (80 mol), propylene glycol 836 mm (11.0 mol), dicyclobentadiene 1
32 (1.0 mol) was mixed at room temperature under a nitrogen stream, and 1.
It takes 6 hours after raising the temperature to 50qo from 150oC to 210
The temperature was raised to 0.00, and dehydration condensation was further carried out for 6 hours to obtain a low-reactivity unsaturated polyester modified with dicyclobentadiene having an acid value of 30.

This unsaturated polyester 65 and hydroquinone 0.0
The unsaturated polyester resin UP-2 was obtained by dissolving 35% of styrene containing 100 ml of styrene. As a result of analysis, the number average molecular weight of this unsaturated polyester was 3000, and as a result of NMR (nuclear magnetic resonance spectrum) analysis, it was found that the maleic acid used in the preparation was 2.
It was found that 35% of the double bonds of maleic acid out of 0 mol reacted with dicyclobentadiene to form an adduct, and 1.3 mol of maleic anhydride had a double bond. Therefore, the molecular weight per double bond is 159
It was 9. [(98 x 0.2 x 148 x 0.8 x 76
×1.0132×0.1×0.9-18.02)÷0
．． 13=1599 In this formula, 0.9 is a coefficient assuming that 10% of dicyclobentadiene is removed from the system without participating in the reaction. ] Using UP-1 and UP-2, SMC with a 1-inch chopped strand content of 27% was produced using glass fiber (glass roving manufactured by Fuji Fiberglass Co., Ltd., FER-0730) with the formulation shown in Table 1,
4000, aged for 4 hours.

When this SMC was molded using a compression molding machine (molding temperature: 140°C, molding pressure: 80k9/base, molding time: 4 minutes), it showed excellent appearance and low shrinkage, and when its mechanical strength was measured, it showed particularly good impact resistance. was excellent.

This is shown in Table 1. Comparative Example 1 Using the unsaturated polyester resin UP-1 produced in Example 1, S with a glass fiber content of 27% was prepared with the formulation shown in Table 1.
MC was prepared and aged at 40:00 for 4 hours.

When this SMC was molded in the same manner as in Example 1,
Compared to Example 1, the shrinkage rate was significantly inferior.

In addition, when mechanical strength was measured, it was found that the impact resistance was poor. Comparative Example 2 Maleic anhydride 118 (1.2 mol), phthalic anhydride 1302 (8.8 mol), propylene glycol 83
6 mols (11.0 mol) were mixed at room temperature under a nitrogen stream, and 15
After raising the temperature to 0°C, the temperature was raised to 15M) to 210°C over 5 hours, followed by dehydration condensation for another 6 hours to obtain a low-reactivity unsaturated polyester with an acid value of 35.

This unsaturated polyester 65 and hydroquinone 0.0
The unsaturated polyester resin UP-3 was obtained by dissolving 35 styrene containing 100 ml of styrene. As a result of analysis, the number average molecular weight of this unsaturated polyester was 2,800, and the molecular weight per double bond was 1,667. UP-3 and Example 1
Using the UP-1 produced in Table 1, SMC with a glass fiber content of 27% was produced according to the formulation shown in Table 1, and aged at 40°C for 4 cycles.

When this SMC was molded in the same manner as in Example 1,
Compared to Example 1, the shrinkage rate was significantly inferior. Furthermore, when mechanical strength was measured, impact resistance was poor. Table 1 Formulation and Properties (Example IP Comparative Examples 1 and 2) * FER-0730 manufactured by Fuji Fiberglass Co., Ltd. (Note) The unit of the formulation number is parts by weight.

The same applies to the table below. Example 2 Maleic anhydride 8
82 moles (9.0 mol), isophthalic acid 166 moles (1.0 mol)
mol) and propylene glycol 912 mol (12.0 mol) were mixed at room temperature under a nitrogen stream, heated to 150°C, heated from 150°C to 210°C over 5 hours, and dehydrated for further 7 hours. Condensation was performed to obtain a highly reactive unsaturated polyester with an acid value of 35.

This unsaturated polyester 65 and hydroquinone 0.0
The unsaturated polyester resin UP-4 was obtained by dissolving the resin in 35 parts of styrene containing 1 part of the resin. As a result of analysis, the number average molecular weight of this unsaturated polyester was 4,000, and the molecular weight per double bond was 179. Maleic anhydride 294 m (3.0 mol), adipic acid 1022 m (7.0 mol)
, dicyclobentadiene 132 mol (1.0 mol), and propylene glycol 836 mol (11.0 mol) were mixed at room temperature under a nitrogen stream, and after raising the temperature to 150 qo, it took 6 hours to raise the temperature from 150 qo to 210 qo. The temperature was raised and dehydration condensation was further carried out for 8 hours to obtain a low-reactivity unsaturated polyester modified with dicyclobentadiene having an acid value of 25.

This unsaturated polyester 65% hydroquinone/0.0
Styrene 35 containing the mixture was dissolved for one night to obtain unsaturated polyester resin UP-5. As a result of analysis, the number average molecular weight of this unsaturated polyester was 3,200, and the molecular weight per double bond was 821. UP-4 and UP-5
Using this, SMC with a glass fiber content of 27% was prepared according to the formulation shown in Table 2, and aged at 40° C. for 4 hours. This SM
When C was molded using a compression molding machine, it showed excellent appearance and low shrinkage, and when its mechanical strength was measured, it was found to have excellent impact resistance.

This is shown in Table 2. Example 3 Maleic anhydride 882 (9.0 mol), isophthalic acid 166 (1.0 mol), propylene glycol 760
dicyclobentadiene (10.0 mol), dicyclobentadiene 198 mol (
1.5 mol) were mixed at room temperature under a nitrogen stream, heated to 150°C, and then heated from 150°C to 21,000°C over 6 hours, followed by dehydration and condensation for another 6 hours to obtain dihydric acid with an acid value of 35.

A highly reactive unsaturated polyester modified with pentadiene was obtained. This unsaturated polyester resin (65%) was dissolved in styrene (35%) containing 0.01% of hydroquinone to obtain unsaturated polyester resin UP-6. As a result of analysis, the number average molecular weight of this unsaturated polyester was 3,500, and the molecular weight per double bond was 226. Using UP-6 and UP-5 produced in Example 2, SMC with a glass fiber content of 27% was produced with the formulation shown in Table 2, and 40q048
Aged for time. When this SMC was molded using a compression molding machine, it showed excellent appearance and low shrinkage, and when its mechanical strength was measured, it was found to have excellent impact resistance.This is shown in Table 2.Table 2 Formulation and Properties (Examples 2 and 3) * FER-0730 manufactured by Fuji Fi' Kuichi Class Co., Ltd. Example 4 UP-1 and UP-2 produced in Example 1 were used, and the glass fiber content was 60 with the formulation shown in Table 3. % SM
C was prepared and aged for 40,004 hours.

When this SMC was molded using a compression molding machine (molding temperature: 140°C, molding pressure: 80k9', molding time: 4 minutes), the molded product had an excellent appearance with no cracks occurring at the corners. Furthermore, when mechanical strength was measured, it was found to have excellent impact resistance. This is shown in Table 3. Comparative Example 3 Using UP-1 produced in Example 1 and UP-3 produced in Comparative Example 2, SMC with a glass fiber content of 60% was produced with the formulation shown in Table 3, and aged for 4 and 4 hours. I let it happen.

When this SMC was molded using a compression molding machine, cracks were found in some corners of the molded product. Furthermore, when mechanical strength was measured, it was found to have excellent impact resistance. Table 3
It was shown to. Table 3 Formulation and characteristics (Example 4, Comparative example 3
) * FER-0730 manufactured by Fuji Fiberglass Co., Ltd. Example 5 Using UP-1 and UP-2 produced in Example 1, resin injection molding was performed with the formulation shown in Table 4 (molding temperature 2500, Injection pressure: 5k9K, molding time: 30 minutes, glass fiber, glass mat FEM-45 manufactured by Fuji Fiberglass Co., Ltd. content: 30%).

The molded product had a good appearance with no cracks occurring at the corners.

Furthermore, when mechanical strength was measured, it was found to have excellent impact resistance. This is shown in Table 4. Comparative Example 4 Using UP-1 produced in Example 1 and UP-3 produced in Comparative Example 2, resin injection molding was performed in the same manner as in Example 5 with the formulations shown in Table 4.

The molded product had cracks at the corners and had poor impact resistance.

Claims (1)

[Scope of Claims] 1. 10 to 95 parts by weight of an unsaturated polyester having a molecular weight per double bond of 140 to 300, an unsaturated polyester having a molecular weight per double bond of 400 to 30,000 and modified with dicyclopentadiene. An unsaturated polyester resin composition containing 5 to 90 parts by weight and 10 to 200 parts by weight of a polymerizable monomer. 2 Unsaturated polyester with a molecular weight per double bond of 140 to 300 has a molecular weight per double bond of 140 to 23
Claim 1, which is an unsaturated polyester having a
The unsaturated polyester resin composition described in . 3. The unsaturated polyester having a molecular weight per double bond of 400 to 30,000 and modified with dicyclopentadiene is an unsaturated polyester having a molecular weight per double bond of 900 to 5,000. Unsaturated polyester resin composition. 4 The molecular weight per double bond is 400 to 30,000, and the unsaturated polyester modified with dicyclopentadiene has a molecular weight of 0.00% of dicyclopentadiene per 1.0 mole of the acid component.
The unsaturated polyester resin composition according to claim 1, 2 or 3, which is an unsaturated polyester obtained by using 0.01 to 0.40 mol. 5. Claim 1, which is an unsaturated polyester obtained by modifying an unsaturated polyester having a molecular weight per double bond of 140 to 300 with dicyclopentadiene,
The unsaturated polyester resin composition according to item 2, 3, or 4. 6. Claims 1, 2, and 2, wherein the molecular weight per double bond is 400 to 30,000, and the unsaturated polyester modified with dicyclopentadiene has a number average molecular weight of 400 to 4,000. Section 3, Section 4
The unsaturated polyester resin composition according to item 1 or item 5.