JP2550644B2 - Cyclic monoperoxyketal - Google Patents

Description

TECHNICAL FIELD The present invention relates to a cyclic monoperoxyketal useful as a radical reaction initiator, more specifically, a polymerization initiator of an unsaturated monomer and an unsaturated polyester resin composition. The present invention relates to a cyclic monoperoxyketal useful as a curing agent for products.

(Prior art) There are various types of organic peroxides, such as diacyl peroxide, peroxyester, diperoxyketal, dialkyl peroxide, and the like.
As a polymerization initiator for unsaturated monomers and a curing agent for unsaturated polyester resin compositions, 150 to 200
Widely used as a crosslinking agent for polyolefins at ℃. The polymerization initiator and the curing agent start the radical addition reaction of the unsaturated monomer, and by the subsequent chain reaction,
The former gives an ordinary polymer and the latter gives a polymer having a knit structure, and is therefore considered to be one type of radical initiator. On the other hand, the cross-linking agent usually gives a cross-linked polymer by a hydrogen abstraction reaction from a polyolefin, and it is functionally completely different from the former two, and the radical chain length is generally very short. is there. Recently, the differentiation of high-molecular organic materials based on their high performance and high functionality, and the development of high value-added products have been actively pursued, and accordingly, requests for radical reaction initiators have been diversified and advanced. In general, such products are differentiated and have high added value by using various polymer additives and modifiers composed of various inorganic compounds and organic compounds having a complicated structure. Therefore, there is a demand for a radical reaction initiator that is stable in the presence of these additives / modifiers and can exhibit good activity during the reaction. In the field of coating plants such as paints and adhesives, monomers having various reactive functional groups are also copolymerized, and a polymerization initiator that does not react with these functional groups is desired. Thus, the use of radical reaction initiators in complex systems is increasing.

Among the organic peroxides, diacyl peroxides and peroxyesters having a carbonyl group are reacted with, for example, an inorganic compound showing an acidic or basic property and an organic compound having a functional group such as a hydroxyl group, an amino group or a sulfide group. It is not preferable for use in a composite system because of its rich nature. Therefore, for use in a complex system, diperoxyketals or dialkyl peroxides containing no carbonyl group are preferred. Examples of such an example include a report that di (t-alkylperoxy) ketal having a neopentyl skeleton is excellent as a radical reaction initiator (Japanese Patent Publication No. 56-29681), and that monoperoxyketal is composed of ethylene and α. -It is reported that it is useful for crosslinking a copolymer with an olefin (JP-B-43-1086).

(Problems to be Solved by the Invention) Diperoxyketals and dialkyl peroxides are chemically stable, but have the drawback of high decomposition temperature. In particular, dialkyl peroxides are usually 12
It is used at a high temperature of 0 ° C or higher, and one having a decomposition activity at a temperature as low as that of a peroxyester is desired. In general, diperoxy ketals and dialkyl peroxides are liable to cause a hydrogen abstraction reaction and are useful as crosslinking agents. The radical reaction initiator used as a polymerization initiator and a curing agent is originally intended to initiate a radical addition reaction, and it is not preferable that the above-mentioned hydrogen abstraction reaction occurs frequently. For example, in the field of coating industry, there is a demand for a polymerization initiator that is stable in a composite system, has few side reactions such as branching and crosslinking, and can effectively introduce a functional group into a polymer. Diperoxy ketal is a kind of bifunctional peroxide and has a factor of broadening the molecular weight distribution. Further, the two t-alkylperoxyl groups on the same carbon atom in the diperoxyketal significantly reduce the compatibility with the unsaturated polyester resin due to the increase in the number of carbon atoms and often lead to incomplete curing. . Furthermore, even monoperoxyketals are not preferable in the case of 1,1-cymethylethylperoxyketal, because they have much higher hydrogen abstraction performance than other ones. From the above, it can be said that the cyclic monoperoxyketal of the present invention relates to improvement of diperoxyketal and dialkyl peroxide.

(Means for Solving the Problems) As a result of intensive studies conducted by the present inventors in search of a radical reaction initiator that has solved the above-mentioned drawbacks, the cyclic monoperoxyketal having the following specific structure is stable. Further, they have found that they have excellent properties in terms of decomposition characteristics, and have completed the present invention. That is, the present invention is a general formula, (Wherein R ¹ , R ² and R ³ are hydrogen or C 1 -C 3
R ⁴ represents an alkyl group having 1 to 5 carbon atoms, and R ⁵ represents an alkyl group having 1 to 3 carbon atoms. Further, when R ⁶ and R ⁷ are separated, R ⁶
Is an alkyl group having 1 to 3 carbon atoms, R ⁷ is an alkyl group having 2 to 10 carbon atoms, a cycloalkyl group or an aryl group, and when they are bonded, a cycloalkane structure is shown. ) Relates to a cyclic monoperoxyketal. The radical reaction initiator referred to in the present invention can be used as a polymerization initiator of an unsaturated monomer mainly composed of a radical addition reaction and a curing agent of an unsaturated polyester resin composition, and cross-linking of a polyolefin mainly composed of hydrogen abstraction reaction. Different from the agent.

The cyclic monoperoxyketal of the present invention is a known method for producing a general peroxyketal (see, for example, US Pat.
3576826 or U.S. Pat. No. 3,468,962). That is, in the presence of an acidic catalyst, the general formula (In the formula, R ¹ , R ² , R ³ and R ⁴ are the same as described above.), Or a general formula (In the formula, R ¹ , R ² , R ³ and R ⁴ are the same as the above.) And the vinyl ether represented by the general formula (In the formula, R ⁵ , R ⁶ and R ⁷ are the same as described above.), Or the reaction with a tertiary alkyl hydroperoxide (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are the same as those described above.) And the general formula R ⁴ —OH (VI). (In the formula, R ⁴ is the same as the above.) And is obtained by a reaction with an alcohol. The acetal of a ketone used in the present invention can be obtained by a known method, that is, a reaction between a ketone and an alcohol in the presence of an acidic catalyst. Specific examples include cyclohexanone or 3,3,5-trimethylcyclohexanone dimethyl, diethyl, diprohill, dibutyl or dipentyl acetal. The vinyl ether used in the present invention is obtained by dealcoholization reaction of the acetal.

Specific examples of the tertiary alkyl hydroperoxide used in the present invention include, for example, 1,1-dimethylethylhydroperoxide, 1,1-dimethylpropylpydroperoxide, 1,1-dimethylbutylhydroperoxide,
1,1,2-trimethylpropyl hydroperoxide, 1,1,
There are 3,3-tetramethylbutyl hydroperoxide, 1-methyl-1-phenylethyl hydroperoxide, pinane hydroperoxide, p-menthane hydroperoxide and 1-methyl (p-isopropylphenyl) ethyl hydroperoxide. The diperoxyketal used in the present invention can be obtained by a known method, that is, by a reaction of an alkyl hydroperoxide, which is relatively stable to an acid, with a ketone in the presence of an acidic catalyst, and specific examples include: , 1,1-dimethylethyl hydroperoxide, 1,1-dimethylpropyl hydroperoxide, diperoxyketal of 1,1-dimethylbutyl hydroperoxide with cyclohexanone or 3,3,5-trimethylcyclohexanone. Further examples of alcohols include methanol, ethanol, propanol and pentanol.

Specific examples of the cyclic monoperoxyketal of the present invention obtained as described above include, for example, 1-methoxy-1- (1,1-dimethylpropylperoxy) cyclohexane and 1-methoxy-1- (1 , 1-Dimethylbutylperoxy) cyclohexane, 1-methoxy-1- (1,
1,2-Trimethylpropylperoxy) cyclohexane, 1-methoxy-1- (1,1,3,3-tetramethylbutylperoxy) cyclohexane, 1-methoxy-1-
(1-Methyl-1-phenylethylberoxy) cyclohexane, 1-butoxy-1- (1,1,3,3-tetramethylbutylperoxy) cyclohexane, 1-methoxy-
1-p-menthane peroxycyclohexane, 1-methoxy-1-pinanperoxycyclohexane, 1-methoxy-1- (1,1,3,3-tetramethylbutylperoxy) -3,3,5-trimethylcyclohexane, 1- Butoxy-1-p-menthane peroxy-3,3,5-trimethylcyclohexane, 1-butoxy-1-pinanperoxy-3,3,5-trimethylcyclohexane, 1-butoxy-
1- (1-methyl-1-phenylethylperoxy)-
Examples include 3,3,5-trimethylcyclohexane.

The chemical structure of the cyclic monoperoxyketal of the present invention was determined by the infrared absorption spectrum, nuclear magnetic resonance spectrum, active oxygen content and refractive index, and its purity was determined by gas chromatography and active oxygen content. The thermal decomposition behavior was determined from the decomposition rate constant in cumene and the half-life. As a result, the half-life at 100 ° C is in the range of 0.5 to 3.0 hours, which is shorter than that of the corresponding di (t-alkylperoxy) ketal which is a conventional radical initiator and decomposes at a lower temperature. It turned out to be a thing.

Examples of the acidic catalyst used for producing the cyclic monoperoxyketal of the present invention include inorganic acids such as sulfuric acid, hydrochloric acid and phosphoric acid, and organic acids such as trifluoroacetic acid and p-toluenesulfonic acid, and silica, alumina and acidic acids. Inorganic solid acids such as clay can also be used. Further, a polymer having an acidic group such as a sulfonic acid group or a carboxyl group such as a cation exchange resin can also be used as a catalyst. The amount of these acidic catalysts used is in the range of 0.01 to 10% by weight based on the dialkyl ketal, vinyl ether or diperoxy ketal used as the raw material.

A solvent may not be used in the production of the cyclic monoperoxyketal of the present invention, but it is desirable to use an inert catalyst in order to promote the reaction smoothly. Specifically, for example, aliphatic and aromatic hydrocarbons having 3 to 12 carbon atoms,
A carboxylic acid ester containing an organic group having 1 to 12 carbon atoms,
What is usually used as a solvent such as carboxylic acid amide, sulfoxide and ether can be used. Reaction is -30
The reaction can be carried out at a temperature of from 70 to 70 ° C. When a dialkyl ketal or diperoxy ketal is used as a raw material, the alcohol or hydroperoxide produced by performing the reaction under reduced pressure may be removed to the outside of the reaction system.

The cyclic monoperoxyketal of the present invention can be used as a polymerization initiator for unsaturated monomers. The unsaturated monomers in that case include olefins such as ethylene, propylene, styrene, vinyltoluene, vinylpyridine, vinylphenol, divinylbenzene and α-methylstyrene; 1,3-butadiene, isoprene and chloroprene. Vinyl esters such as conjugated olefins, vinyl acetate, vinyl bronate, vinyl laurate, vinyl benzoate and divinyl carbonate; allyl esters such as allyl acetate, diallyl carbonate, allyl benzoate and diallyl phthalate; acrylonitrile and methacryl Unsaturated conjugated nitriles such as ronitrile; acrylic acid and methacrylic acid and their esters and amides, for example methyl of acrylic acid and methacrylic acid,
Ethyl, n-butyl, 2-ethylhexyl, glycidyl and hydroxyethyl esters; acrylamide and methacrylamide; maleic anhydride, maleic acid and fumaric acid and their esters; vinyl chloride, vinyl bromide, vinyl fluoride, vinylidene chloride and fluorine. Vinyl halides and vinylidene halides such as vinylidene fluoride; perhaloolefins such as trifluoroethylene, tetrafluoroethylene, hexafluoropropylene and chlor trifluoroethylene;
Included are vinyl ethers and allyl ethers such as methyl vinyl ether, n-butyl vinyl ether, allyl glycidyl ether; acrolein and mixtures thereof.

The polymerization when used as a polymerization initiator is 30 to 150.
By using 0.005 to 10% by weight of the polymerization initiator with respect to the unsaturated monomer at a temperature of ° C., batch polymerization, by well-known general polymerization techniques including bulk polymerization, solution polymerization, emulsion or suspension polymerization techniques. It can be carried out by a method of adding a formula, a continuous type or an unsaturated monomer and / or a polymerization initiator. Furthermore, in the present invention, known polymer additives, modifiers such as polymerization regulators, flame retardants, various fillers, impact resistance enhancers, reinforcing agents, colorants, electrical properties and heat of polymers It can be carried out by using an imparting agent for physical properties, optical properties, magnetic properties, adhesive properties, sliding properties and the like.

When the present invention is used as a polymerization initiator, it can be used in combination with a cyclic monoperoxyketal and in combination with another known polymerization initiator. These are as they are,
Alternatively, it can be used as a solution diluted with an ordinary solvent or as an emulsion or suspension emulsified or dispersed with water.

The cyclic monoperoxyketal of the present invention can also be used as a curing agent for unsaturated polyester resin compositions. This resin composition may contain polymer additives / modifiers such as calcium carbonate, silica, clay, alumina, titanium oxide, zinc white, asbestos, carbon black, glass fiber, carbon fiber, and colorant. it can.

Preferred resin compositions include an ester of propylene glycol and maleic anhydride and phthalic anhydride as the polyester component, and styrene as the unsaturated monomer component.

When used as a curing agent, the unsaturated polyester resin composition is cured at a temperature of 20 to 250 ° C. in an amount of 0.05 to 5.0% by weight of the unsaturated polyester, which is usually used. An azo compound can be used in combination, and can also be used in combination with an accelerator such as an amine or a metal salt.

(Operation) The fact that the cyclic monoperoxyketal of the present invention is superior to known peroxyketals can be explained based on the following mechanism of action from the decomposition rate and estimation from the product: When a cyclic monoperoxyketal is pyrolyzed in a cumene solvent, as shown in the formula (1), first, reversible bond cleavage of an O—O bond occurs in a solvent cage, and subsequently, an alkyl radical is generated.
3 consisting of XIII and IX and alkoxy radical VII
It produces a radically active species and a ketone.

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are the same as described above, but when R ⁷ is phenyl, R ^{6 in} VII and IX.
And R ⁷ alternate).

The three active species act as in the following equations (2), (3), (4) and (5).

(However, m is 0 or 2.) That is, VII undergoes β-cleavage as in formula (2) to yield IX
And ketones, and VII, VIII and IX are
Hydrogen atoms are extracted from cumene as in formulas (3), (4) and (5) to generate corresponding alcohols, esters, alkanes and cumyl radicals.

When an unsaturated monomer is present when the cyclic monoperoxyketal is decomposed, radical active species of VII, VIII and IX are preferentially added to the double bond as shown in the following formula (6). Then, the polymerization is started. However, in the case of an unsaturated monomer such as methyl methacrylate, the alkoxy radical VII undergoes a hydrogen abstraction reaction as shown in the formula (7), which causes a side reaction unfavorable to the physical properties of the polymer. Furthermore, IX is also derived from the polymer produced, for example,
A reaction as shown in formula (8) is caused to generate a branched polymer and a crosslinked polymer.

It is generally considered that such a hydrogen abstraction reaction with an aloxy radical is not preferable for the polymerization of unsaturated monomers [eg, The Journal of Macromolecular Science A. Chemistry (Jour.
nal of Macromolecular Science.Chemitry), Volume 17,
Page 337, described in the 1982 literature. ].

Since the cyclic monoperoxyketal of the present invention has a cyclic structure, ring decomposition occurs at the same time in the decomposition of the formula (1), and therefore the amount of alkoxy radicals produced is small. In addition, except for 1,1-dimethylethylperoxyketal (R ⁵ = R ⁶ = R ⁷ = CH ₃ ),
β-cleavage of the t-alkoxy radical (formula (1) and (2)) occurs relatively easily, and an alkyl radical is likely to occur, which is particularly preferable. In addition, the fact that the O—O bond cleavage in the solvent cage has a reversible equilibrium relationship means that the medium viscosity increases, for example, even in the latter stage of polymerization,
Since the original peroxyketal is regenerated without inactivating the radical pair generated in the solvent basket, high initiator efficiency can be maintained.

On the other hand, when the diperoxyketal (V) is decomposed, the radical active species (X) of the peroxyester is generated as an intermediate according to the formula (9), which is complicated.

X is a chemically unstable peroxyester, which easily decomposes ionicly and often produces an inactive substance which is unfavorable to the physical properties of the polymer, and further decomposes as shown in the formula (10) to form a biradical. It is also a cause of widening the molecular weight distribution.

(Effects of the Invention) Since the cyclic monoperoxyketal of the present invention is constituted based on the above-mentioned mechanism of action, it has several advantages described below.

First is a novel cyclic monoperoxyketal.
This peroxyketal is chemically stable,
It can be used efficiently even in the presence of polymer additives and modifiers. Secondly, the decomposition temperature is lower than that of the corresponding bisperoxyketal, so that it can be used at a low temperature and can generate a large amount of radical active species in a short time, which can be useful for cycle up of the polymerization process. . Figure 3 shows
It is possible to exhibit high initiator efficiency even in a high viscosity medium, for example, in the latter stage of polymerization. Fourth, the ratio of alkyl radicals to the generated radical active species is high, and few things such as hydrogen abstraction adversely affect the polymerization. Compared with diperoxyketal, no peroxyester is formed in the middle, so that a polymer having a small molecular weight and a narrow molecular weight distribution can be obtained. This is preferable when a functional group is introduced into a polymer by copolymerization. Fifth, when the unsaturated polyester resin composition is cured, it is possible to provide a curing agent that has a long pot lie and has good compatibility with the resin.

Next, examples and comparative examples of the present invention will be shown, but the present invention is not limited thereto.

Reference Example 1 [Production of 1-methoxy-1- (1,1-dimethylpropylperoxy) cyclohexane] Maintaining a mixing station of 15.9 g of dimethyl sulfoxide and 1.2 g of p-toluenesulfonic acid at 2 ° C. and 29.1 g of cyclohexanone dimethyl acetal. A mixed solution of 21.1 g of 1,1-dimethylpropyl hydroperoxide was added dropwise. The acid concentration at this time was 0.1 mol / kg reaction mixture. 3 at 20 ° C with stirring
The reaction was completed over time. 20 ml of petroleum ether was added to the reaction mixture, which was washed with 10 ml of water, then with 50 ml of 5% aqueous NaOH solution, three times with 20 ml of water and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure.
% Of 1-methoxy-1- (1,1-dimethylpropylperoxy) cyclohexane was obtained (33.8 g, yield 67%). This was distilled at 43-45 ° C in 0.1 mmHg to obtain the above-mentioned peroxyketal having a purity of 98%.

The peroxyketal of the present invention was confirmed by the amount of active oxygen, elemental analysis, refractive index, IR and NMR spectra, and its structure was confirmed based on the following data.

Active oxygen amount 7.22% (theoretical active oxygen amount 7.40%), elemental analysis C: 65.35%, H: 11.20% (calculated value C: 66.63%, H: 11.18
%), The refractive index n _D ^20: 1.4477, IR spectrum: 1100 cm ^-1 (-
O-Me), NMR speckle: δ3.3 (S, -O-CH 3, 3H), δ
_{1.20 (S, -C (CH 3} ) 2, 6H), δ0.90 (t, CH 2 -CH 3, 3
H).

Example 2 [Production of 1-methoxy-1- (1.1-dimethylbutylperoxy) cyclohexane] A mixed solution of 16.0 g of dimethyl sulfoxide and 1.3 g of p-toluenesulfonic acid was kept at 20 ° C, and 28.8 g of cyclohexanone dimethyl acetal and 1,2. A mixture of 23.8 g of 1-dimethylbutyl hydroperoxide was added dropwise. The acid concentration at this time is
The reaction mixture was 0.1 mol / kg. Thereafter, the same procedure as in Reference Example 1 was carried out. As a result, 1-methoxy-1- (1,1-
39.0 g (yield 69%) of dimethylbutylperoxy) cyclohexane was obtained. This one at 0.1mmHg 47-50 ℃
The peroxyketal having a purity of 97% was obtained by distilling with.

The peroxyketal of the present invention was confirmed by the amount of active oxygen, elemental analysis, refractive index, IR and NMR spectra, and its structure was confirmed based on the following data.

Active oxygen amount 6.74% (theoretical active oxygen amount 6.95%), elemental analysis C: 66.52%, H: 11,25% (calculated value C: 67.79%, H% 11.38
%), Refractive index n _D ²⁰ : 1.4486, IR spectrum: 1100 cm ⁻¹ (−
O-Me), NMR spectrum: δ 3.3 (S, —O—CH ₃ , 3H),
_{δ1.25 (S, -C (CH 3} ) 2-, 6H), δ0.95 (t, CH 2 -CH 3, 3
H).

Example 3 [Production of 1-methoxy-1- (1,1,3,3-tetramethylbutylperoxy) cyclohexane] A mixed solution of 16.1 g of dimethyl sulfoxide and 1.4 g of p-toluenesulfonic acid was kept at 20 ° C to prepare cyclohexane. A mixed solution of 28.9 g of dimethyl acetal and 30,2 g of 1,1,3,3-tetra-methylbutyl hydroperoxide was added dropwise. The acid concentration at this time was 0.1 mol / kg reaction mixture. Thereafter, the same procedure as in Example 1 was carried out, and as a result, 1-methoxy-1- having a purity of 79% was obtained.
40.0 g (yield 69%) of (1,1,3,3-tetramethylbutylperoxy) cyclohexane was obtained. This was purified by distilling off unreacted substances at 33-35 ° C at 0.1 mmHg.
90% of the peroxyketal was obtained. Further, this was purified by silica gel column chromatography using hexane as a mobile phase to obtain the peroxyketal having a purity of 92%.

The peroxyketal of the present invention was confirmed by the amount of active oxygen, elemental analysis, refractive index, IR and NMR spectra, and its structure was confirmed based on the following data.

Active oxygen content 5.71% (theoretical active oxygen content 6.19%), elemental analysis C: 68.69%, H: 11.81% (calculated value C: 69.70%, H: 11.70)
%), Refractive index nd ²⁰ : 1.4567, IR spectrum: 1100 cm ^-1 (-
O-Me), NMR Spectrum: δ3.3 (S, -O-CH 3 3H),
_{δ1.30 (S, -C (CH 3} ) 2-, 6H), δ1.00 (S, -C (C
H _{3) 3,} 9H).

Example 4 [Production of 1-methoxy-1- (1-methyl-1-phenylcetylperoxy) cyclohexane] A mixed solution of 16.2 g of dimethyl sulfoxide and 1.4 g of p-toluene sulfone was kept at 20 ° C, and cyclohexanone dimethyl acetal 29.0 was added. A mixed solution of g and 1-methyl-1-phenylethyl hydroperoxide 27,2 g was added dropwise. The soup concentration at this time was 0.1 mol / kg reaction mixture. Thereafter, the same procedure as in Reference Example 1 was carried out. As a result, 1-methoxy- with a purity of 74% was obtained.
39.5 g (yield 55%) of 1- (1-methyl-1-phenylethylperoxy) cyclohexane was obtained. This was purified by silica gel column chromatography using hexane as a mobile phase to obtain the peroxyketal with a purity of 97%.

The peroxyketal of the present invention was confirmed by the amount of active oxygen, elemental analysis, refractive index, IR and NMR spectra, and its structure was confirmed based on the following data.

Active oxygen amount 8.87% (theoretical active oxygen amount 6.05%), elemental analysis C: 72.25%, H: 9.32% (calculated value C: 72.69%, H: 9.15), refractive index n _D ²⁰ : 1.5087, IR spectrum: 1100 cm ^-1 (-OM
e), NMR Spectrum: δ3.2 (S, -O-CH 3, 3H), δ7.3
-7.6 (Ph-, 5H).

Example 5 [Production of 1-methoxy-1- (1,1-cymethylbutylperoxy) -3,3,5-trimethylcyclohexane] A mixed solution of 20.7 g of dimethyl sulfoxide and 1.6 g of p-toluenesulfonic acid was added at 20 ° C. Then, a mixed solution of 37.3 g of 3,3,5-trimethylcyclohexanone dimethyl acetal and 23.8 g of 1,1-dimethylbutyl hydroperoxide was added dropwise.
The acid concentration at this time was 0.1 mol / kg reaction mixture. Thereafter, the same procedure as in Example 1 was carried out. As a result, 1-methoxy-1- (1,1-dimethylbutylperoxy) -3,3,5 having a purity of 75% was obtained.
50.3 g (yield 68%) of trimethylcyclohexane was obtained. This was distilled at 68-72 ° C. at 0.005 mmHg to obtain the above-mentioned peroxyketal having a purity of 98%.

The peroxyketal of the present invention was confirmed by the amount of active oxygen, elemental analysis, refractive index, IR and NMR spectra, and its structure was confirmed based on the following data.

Active oxygen amount 5.64% (theoretical active oxygen amount 5.87%), elemental analysis C: 69.87%, H: 12.11% (calculated value C: 70.54:, H: 11.84
%), Refractive index n _D ²⁰ : 1.4490, IR spectrum: 1100 cm ^-1 (-
O-Me), NMR spectrum: δ 3.3 (S, —O—CH ₃ , 3H),
_{δ1.27 (S, -C (CH 3} ) 2, 6H), δ1.2-0.90 (> C (CH
_{3) 2,> CH-CH} 3, CH 2 -CH 2 -CH 3, 16H).

Examples 6 to 10 and Comparative Examples 1 to 5 and Reference Example 1 and Comparative Reference Example 1 [Pyrolysis in Cumene] The cyclic monoperoxyketals of the present invention obtained in Examples 1 to 5 and Examples 1 to A 0.05M cumene solution of cyclic bisperoxytakel obtained according to 5 was prepared. A fixed amount was taken from each sample solution into a glass ampule, degassed by a freezing method, and sealed under vacuum. Then, several ampoules were put into a thermostat at 100 ° C. and taken out at regular intervals, and the concentration of peroxyketal was measured by gas chromatography or liquid chromatography. The rate constant and half-life were calculated from the disappearance rate of each peroxyketal. The obtained results are shown in Table 1 as Examples 6 to 10 and Comparative Examples 1 to 5.
In addition, a 1,1-dimethylethylperoxy derivative was produced according to Example 1, and similarly pyrolyzed. The results are shown in Table 1 as Reference Example 1 and Comparative Reference Example 1.

Comparison of the examples with the comparative examples reveals that the cyclic monoperoxyketals of the invention decompose considerably faster than the corresponding cyclic bisperoxytakels and are peroxides active at even lower temperatures. It was

Examples 2 to 4 [Solvent effect] In place of cumene, n-hexane, n-dodecane and n-hexadecane were used as the solvent, and 1-methoxy-1- (1,1- Thermal decomposition of dimethylethylperoxy) cyclohexane was carried out at 100 ℃ and the thermal decomposition rate constant and half-life were determined. The results are shown in Table 2 as Reference Examples 2 to 3.

From Reference Examples 2 to 4, since the decomposition rate is delayed with the increase of the solvent viscosity, the thermal decomposition of the cyclic monoperoxyketal of the present invention is carried out in the solvent cage as shown by the reaction formula (1). It can be seen that the reversible bond cleavage of the O-O bond is caused. That is, the increase in solvent viscosity regenerates the original peroxyketal without producing an inert substance. This indicates that high initiator efficiency can be maintained even in high viscosity media.

Reference Example 5 and Comparative Reference Example 2 [Pyrolysis Products in Cumene] Various pyrolysis products were measured by gas chromatography for the pyrolysis solutions obtained in Reference Example 1 and Comparative Reference Example 1. 1 mol of each decomposed peroxyketal
Mol product per hit was determined. The results obtained respectively,
The results are shown in Table 3 as Example 5 and Comparative Example Reference Example 2.

The results of Reference Example 5 and Comparative Reference Example 2 show that the cyclic monoperoxyketal of the present invention and the cyclic bisperoxytakel listed as a comparative example are represented by formulas (1) to (5) and (5) to (5), respectively. It shows that decomposition is performed according to Eq. (10).

Examples 11 to 15 and Comparative Examples 6 to 11 [Amount of Ketone and Alcohol Produced by Pyrolysis in Cumene] Gas of the pyrolysis solution obtained in Examples 6 to 10 and Comparative Examples 1 to 5 and Reference Example 1 The ketone and alcohol produced by chromatography were measured. The number of mol of product per mol of each decomposed belloxy ketal was determined. The obtained results are shown in Table 4 as Examples 11 to 15 and Comparative Examples 6 to 11.

From the equations (2) and (3), the production ratio of ketone with respect to the production amount of alcohol is a measure of the production amount of alkoxy radical. When the examples and the comparative examples in Table 4 are compared, the cyclic monoperoxyketal of the present invention is 1-
Methoxy-1- (1,1-dimethyl ester belloxy)
It produces less alkoxy radicals than cyclohexane and cyclic bisperoxytakel, and peroxyketals having a 1,1-dimethylethylperoxyl group have more alkoxy radicals than those having other t-alkylperoxyl groups. It can be seen that a large amount is generated.

Examples 16 to 22 and Comparative Examples 12 to 18 [Polymerization of unsaturated monomer] The cyclic monoperoxyketal of the present invention obtained by Examples 1 to 5 and 1 obtained according to Example 1
-Methoxy-1- (1,1-dimethylethylperoxy)
Cyclohexane and cyclic bisperoxyketals of 0.
A 01 mol / L styrene solution and 2.0 g / L styrene were prepared. A fixed amount was taken from each sample solution into a glass ampule, deaerated by a freeze-thaw method, and sealed under vacuum. Then, several ampoules were placed in a constant temperature bath of 80 ° C. and taken out at predetermined intervals and cooled to −20 ° C. or lower. Then, the ampoule was opened, the polymer was precipitated from the benzene solution with methanol, filtered, and then vacuum dried for 24 hours. The polymerization rate was determined by the gravimetric method. The molecular weight of the obtained polymer was measured by GPC. The results at a polymerization conversion of 10% are shown in Examples 16 to 20 and Comparative Examples 12 to 18.
5 shows.

By comparison between the examples of Table 5 and the comparative examples, the cyclic monoperoxyketals of the present invention have 1-methoxy-1- (1,
It can be seen that, compared with 1-dimethylethylperoxy) cyclohexane and cyclic bisperoxyketal, a polymer having a higher polymerization rate and a low molecular weight can be obtained.

Examples 21 and 22 and Comparative Examples 19 and 20 (Production of cyclyl resin) Stirrer, a glass reactor equipped with a thermometer and a reflux condenser, 30 g of isooctyl acetate as a solvent, 30 g of butyl acrylate, 20 g 2-vidroxyethyl acrylate, 20 g butyl methacrylate, 30 g
Of styrene and 0.030 molar equivalent of peroxyketal in terms of the amount of active oxygen and a mixture of the initiators were added dropwise at a temperature of 125 ° C. in a nitrogen atmosphere over 5 hours, and then stirring was continued for another 2 hours to carry out polymerization. It was completed. As the initiator, the cyclic monoperoxyketal produced in Example 2 and 1-methoxy-1- (1,1-dimeraethylperoxy) cyclohexane and cyclic bisperoxyketal synthesized in accordance with the cyclic monoperoxyketal were used. The results are shown in Example 21 and Comparative Examples 19 and 20.
6 is shown. The molecular weight is determined by GPC using polystyrene as a standard.

The comparison between the examples and comparative examples in Table 6 shows that the molecular weight of the acrylic resin obtained by using the cyclic monoperoxyketal of the present invention is 1,1-dimethylethylperoxyl derivative and the corresponding cyclic bisperoxy. It shows that the average molecular weight is smaller and the molecular weight distribution is narrower than when ketal is used.

Examples 22 to 26 and Comparative Examples 21 to 28 [Curing of unsaturated polyester resin] The unsaturated polyester resin used was Epolak G110.
It is AL (manufactured by Nippon Shokubai Chemical Factory) and the curing method is JIS K6901.
According to the liquid unsaturated polyester resin test method.

Cyclic monoperoxyketal was added to unsaturated polyester resin and a curing test was conducted in a thermostat at 80 ° C to measure gelation time (GT), curing time (CT) and maximum exothermic temperature (PET). The catalyst conversion amount at this time was converted into the amount of active oxygen with respect to the unsaturated polyester resin, and made equal to 1% by weight of t-butylperoxybenzoate.

Further, the pot life of the unsaturated polyester resin containing the catalyst at 40 ° C. was visually measured. The obtained results are shown in Examples 22 to 26 and Comparative Examples 21 to 28.
7 shows.

From the results of Table-7, peroxyketals having no carbonyl group were compared with t-butyl peroxybenzeate having a carbonyl group, although the gelation and curing time were shorter. You can see that it is long. In addition, the cyclic monoperoxyketal of the present invention has a shorter degemination and curing time than the 1,1-dimethylethylperoxy derivative and the corresponding cyclic bisperoxyketal, and is more soluble in the resin than the latter. It can be seen that it exhibits excellent curing characteristics.

Claims (3)

(57) [Claims] 1. A general formula (Wherein R ¹ , R ² and R ³ are hydrogen or C 1 -C 3
R ⁴ represents an alkyl group having 1 to 5 carbon atoms, and R ⁵ represents an alkyl group having 1 to 3 carbon atoms. Further, when R ⁶ and R ⁷ are separated, R ⁶
Is an alkyl group having 1 to 3 carbon atoms, R ⁷ is an alkyl group having 2 to 10 carbon atoms, a cycloalkyl group or an aryl group, and when they are bonded, a cycloalkane structure is shown. ) A cyclic monoperoxyketal represented by: 2. The ring according to claim 1, wherein R ⁶ and R ⁷ are separated, R ⁶ is an alkyl group having 1 to 3 carbon atoms, and R ⁷ is an alkyl group having 2 to 10 carbon atoms. Formula monoperoxyketal. 3. The cyclic monoperoxyketal according to claim 1, wherein R ⁶ and R ⁷ are separated, and R ⁶ is an alkyl group having 1 to 3 carbon atoms and R ⁷ phenyl group.