JP2001114757A - Alkylperoxymethyl-substituted benzoate, resin composition and molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a peroxide having a proper plate gel time, capable of shortening a rise time in curing a thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin. SOLUTION: This alkylperoxymethyl-substituted benzoate is represented by the formula (R is a 1-5 alkyl group; n is an integer of 1 or 2) and is suitable for a curing agent for a thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin, etc. This polymerization initiator, crosslinking agent or curing agent comprises the compound as an active ingredient. The thermosetting resin composition (molding material) comprises the compound. This thermosetting resin molded product is cured by using the compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an alkylperoxymethyl-substituted benzoate useful as a curing agent for a thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin, and a resin composition containing the same as a curing agent, especially a sheet. Molding compound (hereinafter abbreviated as SMC)
And molding materials such as bulk molding compounds (hereinafter abbreviated as BMC).

[0002]

2. Description of the Related Art MMD (Matched Metal)
Die), molding materials typified by artificial marble include a curing agent added to a thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin, and, if necessary, a thickener, a filler, a low-shrinking agent, After mixing a mold agent, an inhibitor, and a vinyl monomer, the mixture is processed into a sheet, pellet, bulk, or the like.

[0003] These molding materials are widely used in industrial applications such as molding into automobile parts, electric parts, housing equipment, housing materials, septic tanks, etc. by various press molding methods such as compression molding, transfer molding and injection molding. It has come to be.
Since the curing agent used in such a molding material has a great effect on the quality and productivity of the molding material at the time of press molding, sufficient care must be taken in its selection.

The molding material is generally 100 ° C. to 160 ° C. in consideration of productivity in molding and curing into a molded article.
Various peroxides and azo compounds that decompose at such a temperature are used as curing agents because they are molded and cured at a temperature of ° C. Among them, tertiary butyl peroxybenzoate (hereinafter abbreviated as TBPB) is widely used because of its good total balance.

[0005] A method of manufacturing a molded body using a molding material is not limited to the initial investment cost and the design is free. It has been reviewed as a medium-sized production tool, and its demand has recently increased. Along with this, the development of high-speed presses aimed at improving productivity by shortening the molding cycle, and the mechanization and automation of processes before and after press molding, such as automatic SMC charging machines, have further advanced.

[0006]

With the above-mentioned changes in the production process, the curing agent has been required to have a performance capable of shortening the production cycle. The ability to shorten the cycle means that the time required for the molding material to flow in the press machine mold (plate gel time) is shortened within an appropriate range, and after the molding material flows into the press machine mold. This is a performance that makes it possible to shorten the time until the curing (rise time). TBPB mentioned above
Although the plate gel time is short within an appropriate range, there is a disadvantage that the rise time is long. Therefore, there is a demand for development of a curing agent having a property that the plate gel time is short within an appropriate range and the rise time is short.

[0007]

Means for Solving the Problems As a result of intensive studies to satisfy the above-mentioned demands, the present inventors have found that plate gel time can be shortened within an appropriate range by using an alkylperoxymethyl-substituted benzoate as a curing agent. In addition, they have found that the rise time can be shortened, and have achieved the present invention.

That is, the present invention provides (1) an alkylperoxymethyl-substituted benzoate represented by the following formula (1).

[0009]

Embedded image

Wherein R is an alkyl group having 1 to 5 carbon atoms, n
Represents an integer of 1 or 2. (2) A polymerization initiator, a cross-linking agent or a curing agent containing an alkylperoxymethyl-substituted benzoate represented by the formula (1) as an active ingredient. (3) The curing agent according to (2), which is a curing agent for a thermosetting resin. (4) A resin composition containing an alkylperoxymethyl-substituted benzoate represented by the formula (1) and a thermosetting resin. (5) The resin composition according to (4), wherein the thermosetting resin is an unsaturated polyester resin or a vinyl ester resin. (6) The resin composition according to (4) or (5), which is a molding material. (7) A thermosetting resin molded article cured using the alkyl peroxymethyl-substituted benzoate represented by the formula (1). (8) The thermosetting resin molded article according to (7), wherein the resin is an unsaturated polyester resin or a vinyl ester resin. About.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail. In the above general formula, the alkyl group having 1 to 5 carbon atoms may be branched or unbranched, for example, a methyl group, an ethyl group,
Examples include a normal or isopropyl group, a normal or isobutyl group, an amyl group, and the like. Further, the methyl group on the benzene nucleus may be either one or two, and the substitution position is not particularly limited. For example, when there is one methyl group, it may be any of the 2-, 3- or 4-position, and the 2- or 3-position is preferred. When there are two methyl groups, any of 2-position, 3-position, 2-position and 4-position, 2-position and 5-position, 3-position and 4-position, 3-position and 5-position may be used, but 2-position and 4-position are preferred.

Illustrative peroxides that can be used in the present invention are tertiary butylperoxy-2-methylbenzoate, tertiary butylperoxy-3-methylbenzoate, tertiary butylperoxy-4-methylbenzoate and tertiary amyl peroxide. Oxy-2
-Methyl benzoate, tertiary amyl peroxy-3-methyl benzoate, tertiary amyl peroxy-4-methyl benzoate, tertiary hexyl peroxy-2-methyl benzoate, tertiary hexyl peroxy-3-methyl benzoate, tertiary Hexyl peroxy-4-methylbenzoate, tertiary octyl peroxy-2-methyl benzoate, tertiary octyl peroxy-3-methyl benzoate, tertiary octyl peroxy-4-methyl benzoate, tertiary butyl peroxy-2,
4-dimethylbenzoate, tertiary amyl peroxy-2,4-dimethylbenzoate, tertiary hexyl peroxy-2,4-dimethylbenzoate, tertiary octyl peroxy-2,4-dimethylbenzoate and the like.

The synthesis of the alkyl peroxymethyl-substituted benzoate of the present invention represented by the above formula (1) can be carried out according to a usual peroxide production method. That is, a hydroperoxide RC (CH ₃ ) ₂ —O—O—H (2) represented by the following formula (2) (wherein R has the same meaning as described above) and the following formula (3) methyl-substituted benzoyl chloride _Cl-Phe shown (CH 3) n (3) ( wherein Phe denotes phenyl group, a _(CH 3) n are as defined above it is .n showing a methyl substituent on a phenyl group Can be obtained by carrying out a condensation reaction under ordinary reaction conditions, that is, in the presence of an alkali agent such as potassium hydroxide at a reaction temperature of 20 ° C. or lower for 1 to 2 hours. For example, when tertiary butyl peroxy-2-methylbenzoate (hereinafter abbreviated as TB2MB) is described, tertiary butyl hydroperoxide and 2-
Methylbenzoyl chloride is reacted under normal reaction conditions,
The reaction temperature is 2 in the presence of an alkaline agent such as potassium hydroxide.
It can be obtained by conducting a condensation reaction at 0 ° C. or lower for 1 to 2 hours.

The alkyl peroxymethyl-substituted benzoate represented by the above formula (1) can be used for various uses such as a polymerization initiator for a vinyl monomer, a crosslinking agent for a resin and a curing agent, like other peroxides. Are particularly preferred as curing agents for thermosetting resins such as unsaturated polyester resins and vinyl ester resins. The thermosetting resin in the present invention has a polymerizable vinyl group in the structure of the resin,
Any resin can be used as long as it can be three-dimensionally cured by heating, but preferred are unsaturated polyester resins and vinyl ester resins.

Here, the unsaturated polyester resin includes:
An unsaturated dibasic acid is always used as one component, and if necessary, a reaction product obtained by heating and dehydrating and condensing with glycols using a saturated dibasic acid is diluted with a vinyl monomer such as styrene. One. Examples of unsaturated dibasic acids that can be used include maleic anhydride, fumaric acid, citraconic acid, chloromaleic acid and the like. Examples of the saturated dibasic acid that can be used include phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid and the like. Examples of glycols that can be used include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, hexanediol, bisphenol A, and propylene oxide adducts. Such an unsaturated polyester resin can be easily obtained from the market.

Next, examples of the vinyl ester resin include those obtained by diluting an equivalent reaction product of a polyepoxide and an α, β-unsaturated monobasic acid with a vinyl monomer. Examples of polyepoxides that can be used include epibis glycidyl ethers such as bisphenol A and bisphenol F, novolak glycidyl ether, brominated glycidyl ether,
Examples include nitrogen-containing polyepoxides such as triglycidyl isocyanurate, glycidyl esters such as phthalic acid and hexahydrophthalic acid, and glycol-type glycidyl ethers. Examples of α, β-unsaturated monobasic acids that can be used include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid,
And sorbic acid. In the present invention, the resin to be cured may be a mixture of an unsaturated polyester resin and a vinyl ester resin.

The amount of the thermosetting resin and the curing agent of the present invention in the resin composition of the present invention is usually about 0.1 to 3 parts by weight of the curing agent of the present invention per 100 parts by weight of the thermosetting resin. And preferably about 0.5 to 2 parts by weight.
If the amount is less than 0.1 part by weight, the effect as a curing agent often becomes insufficient. Also, even if 3 parts by weight or more is used, the effect as a curing agent is not so different from that of 3 parts by weight, which is disadvantageous in terms of economy.

The thermosetting resin composition of the present invention can be used in addition to the alkylperoxymethyl-substituted benzoate represented by the formula (1) and the thermosetting resin, and if necessary, a thickening agent for a molding material (for example, an oxidizing agent). Magnesium, finely divided silica, calcium hydroxide, etc .; usually about 0.2 to 5 parts by weight, preferably about 0.5 to 3 parts by weight, based on 100 parts by weight of the thermosetting resin, a filler (for example, calcium carbonate, Aluminum hydroxide, clay, talc and the like; usually about 50 to 500 parts by weight, preferably about 100 to 300 parts by weight, based on 100 parts by weight of the thermosetting resin, a low shrinkage agent (for example, polystyrene, polyethylene, polypropylene and the like); Usually about 5 to 100 parts by weight, preferably about 10 to 50 parts by weight, based on 100 parts by weight of the thermosetting resin. ), Release agents (eg, zinc stearate, calcium stearate, wax, etc .; usually about 1 to 20 parts by weight, preferably about 2 to 10 parts by weight, based on 100 parts by weight of the thermosetting resin), and inhibitors (eg, Parabenzoquinone, hydroquinone, etc .; usually 0 to 0.1 based on 100 parts by weight of the thermosetting resin.
Parts by weight) or glass fiber (for example, chopped strand, continuous mat, etc .; thermosetting resin 1)
Usually about 0 to 500 parts by weight with respect to 00 parts by weight)
Can be used as a molding material.
Optional ingredients, thickener, filler, low shrinkage agent, release agent,
The polymerization inhibitor, glass fiber, and the like can be arbitrarily changed within a range usually used depending on the type of the additive, the purpose of use of the molding material, and the like. The total amount of the optional components is, for example, 0 to 500 parts by weight, preferably about 1 to 400 parts by weight, more preferably about 10 to 300 parts by weight, based on 100 parts by weight of the thermosetting resin composition. It is. In addition, vinyl monomers (such as styrene, methyl methacrylate, diallyl phthalate, and vinyl toluene) are usually included as a component of the thermosetting resin, but may be added as a component of the thermosetting resin as necessary. May be used.

When the above composition of the present invention is used as a molding material, it is adjusted, for example, for 1-2 days,
It is desirable to carry out a thickening treatment under conditions such as applying a temperature of 5 ° C to 50 ° C.

When the alkylperoxymethyl-substituted benzoate of the present invention represented by the formula (1) is used as a curing agent for a thermosetting resin, it is mixed with the thermosetting resin and other components in advance as described above. Therefore, it may be a thermosetting resin composition that can be used as a molding material,
Also, it may be added directly when the thermosetting resin is cured. In this case, the addition amount of the curing agent is 0.1 to 3 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the thermosetting resin, as in the case where the curing agent is added in advance. Parts. The curing agent of the present invention may be used in combination with a known curing agent such as TBPB, if necessary.

The molding temperature at the time of obtaining a molded article using the resin composition of the present invention is usually 100 ° C. or higher, preferably 120 ° C.
As described above, the temperature is preferably 160 ° C. or less. Below 100 ° C,
When the curing agent of the present invention does not sufficiently act as a curing agent, or when the temperature exceeds 160 ° C., a problem may occur in fluidity in a mold. As a molding method, various press molding methods such as compression molding, transfer molding, and injection molding can be adopted. The molded article molded by the above molding method is suitably used as an automobile part, an electric part, a housing equipment, a housing material, a septic tank, or the like.

[0023]

The present invention will be described below with reference to examples and comparative examples, but these are only for illustration and do not limit the present invention. In Examples and Comparative Examples, "parts" represents parts by weight.

Example 1 In a 1000 cc beaker, 150 parts of water and 136 parts of tertiary butyl hydroperoxide were added to 48%
Add 134 parts of an aqueous potassium hydroxide solution and stir well.
Next, 155 parts of 2-methylbenzoyl chloride are added dropwise over 40 minutes while cooling to 20 ° C. The reaction is continued at the same temperature for 60 minutes after the completion of the dropwise addition. Next, the reaction solution was separated using a separating funnel, and the organic layer was washed and dehydrated.
89 parts were obtained. The yield was 96.4%, the active oxygen content by iodometric titration was 7.6%, and the purity was 99.0%.
Met. Here, the amount of active oxygen means a value defined by the following equation. Active oxygen content (%) = ((number of peroxide bonds × 16) ÷ molecular weight) × purity (%) In this example, 155 parts of 3-methylbenzoyl chloride were used instead of 155 parts of 2-methylbenzoyl chloride. And tertiary butyl peroxy-3-methylbenzoate (TB3MB)
189 parts were obtained. The yield was 96.1%, the active oxygen content by iodometry was 7.6%, and the purity was 98.5.
%Met.

Example 2 The procedure of Example 1 was repeated, except that 150 parts of tertiary amyl hydroperoxide was used in place of tertiary butyl hydroperoxide. Amyl peroxy-2-methylbenzoate (TA2MB) 275
Got a part. The yield was 94.1%, the active oxygen content by iodometric titration was 6.6%, and the purity was 84.5%.

Example 3 In Example 1, 150 parts of tertiary amyl hydroperoxide was used instead of tertiary butyl hydroperoxide, and 200 parts of 2,4-dimethylbenzoyl chloride was used instead of 2-methylbenzoyl chloride. The others were synthesized according to Example 1 to obtain tertiary amyl peroxy-2,4
-250 parts of methyl benzoate (TA2.4MB) were obtained. The yield was 97.0%, the active oxygen content by iodometric titration was 6.2%, and the purity was 85.5%.

Example 4 80 parts of a commercially available unsaturated polyester resin for SMC (Polylite PS-281 manufactured by Dainippon Ink and Chemicals, Inc.) and a polystyrene-based low shrinkage agent (Dainippon Ink and Chemicals, Inc.) Polylite PS-954) 2
0 parts, calcium carbonate (NS # 1 manufactured by Nitto Powder Chemical Co., Ltd.)
00) 150 parts, zinc stearate 5 parts and magnesium oxide 1 part were added, and TB2MB of the present invention was added to 1.0 phr.
(Phr: parts by weight per 100 parts by weight of resin, pe
r hundred resin; the same applies hereinafter), and in order to further adjust the plate gel time (T0), add P-benzoquinone (C6H4O2) in the amount shown in Table 1 (0.05 p
hr), and the mixture was mixed for a certain period of time so as to be sufficiently uniform with a glass rod to obtain a thermosetting resin composition (molding material) of the present invention. This was then sealed with a polyethylene terephthalate film for use in the curing test and thickened at 40 ° C. for 24 hours.

This thickened molding material (compound)
About Orientec JSR Curast Meter 3S. D type (die resin type, amplitude angle ± 1/4)
The torque value during the curing process of the compound was measured. The time (T0) from the start of the measurement to the development of the torque was measured and defined as the plate gel time. The torque value corresponding to 90% of the torque value at which the torque is maximized is set to 90% maxF.
And the time (T90) until reaching 90% maxF was measured. Next, the time until reaching 90% maxF (T9
The rise time was calculated by subtracting the time (T0) until the torque appeared from (0) (T90-T0). Table 1 shows the results. T0 represents a plate gel time, and is preferably about 40 to 45 seconds in terms of work. Also T90,
It is preferable that T90-T0 be both small.

Example 5 The procedure of Example 4 was repeated, except that tert-butylperoxy-3-methylbenzoate (hereinafter abbreviated as TB3MB) was used instead of TB2MB. After obtaining a curable resin composition and thickening it in the same manner as in Example 4, T0 and T90 were measured, and T0-T90 was calculated. The results are shown in Table 1.

Example 6 The procedure of Example 4 was repeated, except that tertiary amyl peroxy-2-methylbenzoate (hereinafter abbreviated as TA2MB) was used instead of TB2MB. After obtaining a curable resin composition and thickening it in the same manner as in Example 4, T0 and T90 were measured, and T0-T90 was calculated. The results are shown in Table 1.

Example 7 The procedure of Example 4 was repeated, except that tertiary amyl peroxy-2,4-dimethylbenzoate (hereinafter abbreviated as TA2.4MB) was used instead of TB2MB. Obtain the thermosetting resin composition of the present invention,
After thickening in the same manner as in Example 4, T0 and T9
0 was measured, and T0-T90 was calculated. Table 1 shows the results.
It was shown to.

Comparative Example 1 Examples 4 to 7 were the same as those in Example 4 except that TBPB was used in the amount shown in Table 1 in place of TB2MB.
In the same manner as in Examples 4 to 7, a thermosetting resin composition (molding material) for comparison was prepared and cured in the same manner as in Examples 4 to 7, and the curast properties (T0, T90, T0) were obtained.
-T90) was measured and calculated. Table 1 also shows the results
It was shown to.

Table 1 Composition Table and Result of Curing Test Addition amount P-benzocurast characteristics Quinone (measured at 140 ° C.) Addition amount T0 T90 T90 Example Curing agent-T0 number (phr) (phr) sec. Sec. TB2MB 1.0 0.05 42 157 115 115 TB3MB 1.00 42 142 100 100 TA2MB 1.0 0.04 42 133 91 7. TA2.4MB 1.0 0.05 42 126 84 Comparative Example 1. TBPB 1.00 42 183 141

TB2MB, TB3MB, TA2 of the present invention
When using MB, TA2.4MB, TB of comparative example
T90-T0 (rise time) is considerably shorter than that of PB, indicating that the alkyl peroxymethyl-substituted benzoate represented by the formula (1) of the present invention is suitable as a curing agent for a thermosetting resin. .

[0035]

When the alkylperoxymethyl-substituted benzoate represented by the formula (1) of the present invention is used as a curing agent for a thermosetting resin, the flow time (plate gel time) in the mold during press molding is appropriate. In addition, it is possible to shorten the time (rise time) until hardening after flowing in the mold, thereby shortening the production cycle.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (reference) C08L 101/16 C08L 101/00 F term (reference) 4H006 AA01 AB40 AB49 4J002 CD201 CF201 EA046 EH076 EH146 EK047 FA040 FD010 FD147 FD160 FD200 FD330 GL00 GN00 GQ00 HA04 4J015 BA07 4J027 AB02 AB06 AB07 AB08 AB15 AB16 AB17 AB18 AB23 AB24 AB25 AE02 AE03 AE04 AE05 AE06 BA05 BA07 BA22 CA02 CA04 CA14 CA18 CA19 CA32 CA36 CA38 CB03 CC02 CD01

Claims (8)

[Claims] An alkyl peroxymethyl-substituted benzoate represented by the following formula (1): Embedded image Wherein R is an alkyl group having 1 to 5 carbon atoms, and n is 1 or 2
Indicates an integer. ) 2. A polymerization initiator, a crosslinking agent or a curing agent comprising an alkylperoxymethyl-substituted benzoate represented by the formula (1) as an active ingredient. 3. The curing agent according to claim 2, which is a curing agent for a thermosetting resin. 4. A resin composition comprising an alkylperoxymethyl-substituted benzoate represented by the formula (1) and a thermosetting resin. 5. The resin composition according to claim 4, wherein the thermosetting resin is an unsaturated polyester resin or a vinyl ester resin. 6. The resin composition according to claim 4, which is a molding material. 7. A thermosetting resin molded article cured by using an alkylperoxymethyl-substituted benzoate represented by the formula (1). 8. The thermosetting resin molded article according to claim 7, wherein the resin is an unsaturated polyester resin or a vinyl ester resin.