JPS5915908B2 - Method for producing a novel peracid ester suitable for initiating radical reactions - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for the preparation of novel peracid esters suitable for carrying out chemical reactions initiated by free radicals.

Ethylenically unsaturated polymerizable monomers such as ethylene, styrene, methyl methacrylate, vinyl chloride, vinyl acetate and other vinyl esters, 0 or ethylene and vinyl acetate, styrene and acrylics, nitriles, vinyl chloride and vinyl acetate It is known that these polymerizable monomer mixtures, such as, can be polymerized or copolymerized by adding free radical-generating compounds.

-5 It is also known to add free radical-generating compounds to induce copolymerization of unsaturated polyester resins. Dutch Patent Publication No. 71-149
No. 92 is a general initiator for radical polymerization and copolymerization.
It is proposed to use compounds of the formula S-O-O-C-CH3, where n is 1 or 2.

It has now been found that peracid esters having the general formula (wherein n is 1 or 2) are extremely suitable for chemical reactions, more specifically for radical polymerization and copolymerization.

Examples of the new peracid ester obtained by the present invention are 2.4
・4-trimethyl-pentyl-2-peroxo cyclohexane carboxylate, 1,4-bis-(2
・4・4-Trimethylpentyl-2-peroxycarbonyl)cyclohexane, 1,3-bis-(
2, 4, 4-trimethyl pentyl-2-
peroxycarbonyl)cyclohexane and 1,2-bis-(2.4.4-trimethyl-pentyl-2-peroxycarbonyl)cyclohexane.

The new peresters obtained according to the invention exhibit much higher reactivity than the tert-butyl peresters of NL 71-14992.

An indication of the reactivity of a peroxide at a given temperature is the polymerization rate constant (Kp) of the formula: where Rp = polymerization rate, K = polymerization rate constant P ) can be derived from

The new peracid ester obtained by the present invention is vinyl chloride,
Radical polymerization and copolymerization of polymerizable monomers containing vinyl or vinylidene groups such as methyl methacrylate, acrylonitrile and acrylic esters.
It can be used to carry out the copolymerization of unsaturated polyesters at temperatures ranging from 0° to 100°C and at temperatures ranging from 60°C to 180°C.

Moreover, the peracid esters of the present invention can be used as initiators for the high-pressure polymerization of ethylene at temperatures above 130°C.
According to U.S. Pat. No. 3,367,994, unsaturated polyester resins include unsaturated polyesters and monomers containing vinyl or vinylidene groups such as styrene, vinyltoluene, methyl methacrylate, diallyl phthalate, and divinyl benzene. species or a mixture of more than one species.

Generally, the mixture contains 30-50% by weight monomer and 70-50% polyester. The unsaturated polyester may contain a polyhydric alcohol such as ethylene glycol, propylene glycol, diethylene glycol, and approximately equivalent amounts of anhydrides of maleic, fumaric, itaconic, or equivalent acids, if desired, and phthalate. Obtained by reaction in the presence of acids, isophthalic acid, tetrachlorophthalic acid, malonic acid, adipic acid, succinic acid, sebacic acid and similar saturated acids. The peresters of the present invention have been found to be very suitable for use in high temperature molding of unsaturated polyester resin mixtures. The mixtures applied here are usually fillers such as calcium carbonate, kaolin or talc, reinforcing materials such as glass fibres, lubricants such as stearic acid, zinc stearate and phosphoric esters. It also contains pigments. In this use, the novel peracid esters of the present invention are also described in Dutch Patent Publication No. 71-1.
It was found to be more effective than the corresponding peracid tert-butyl ester of No. 4992. The peresters of the present invention result in products with less residual styrene in the final product over a wide temperature range. Moreover, the gloss of the final product is lower than that of the corresponding peracid T, especially when the molding time is short.
It has been found that the gloss of the final product obtained using ert-butyl ester is much better. When the 2,4,4-trimethylpentyl-2-peroxy cyclohexane carboxylate of the present invention is used for high-temperature molding of the above-mentioned unsaturated polyester resin,
Even better effects can be obtained by adding metal compounds such as iron compounds, cobalt compounds or manganese compounds. Gel time and minimum curing time increase while "peak"
The level of "exotherm" (maximum heat generation) is maintained.
"Peak exotherm" is the highest temperature reached during copolymerization when a mixture of 25y is placed in a constant temperature bath. This slowing of polymerization during processing allows for better flow of the molding stock and therefore better filling of the mold. For the monomers to be copolymerized or the polyester/still resin to be cured, the peracid ester of the present invention may be added as is, or a plasticizer such as dimethyl phthalate, dibutyl phthalate, or dioctyl phthalate, an adipate ester, or an epoxidized oil. , monofunctional or difunctional alcohols, aliphatic hydrocarbons such as hexane or white spirit, aromatic hydrocarbons such as benzene or toluene, esters such as methyl acetate, ethyl acetate or butyl acetate or ketones such as acetone. 0.01 to 5% by weight of the monomer to be copolymerized or the polyester resin to be cured, dissolved in or diluted in an inert mineral material such as silicates or silicates. Add the amount of

If desired, they can also be mixed with other additives into the material to be (co)polymerized by methods known per se. The peracid esters of the present invention include known peroxides such as acetyl cyclohexane sulfonyl peroxide, dicarbonates such as diisopropyl peroxy dicarbonate and bis(4-Tert-butyl cyclohexyl) peroxy carbonate,
Tert-butylperoxy pivalate, Tert-
Peracid esters such as butyl peroxyneodecanoate, tert-butyl peroxy acetate, tert-butyl peroxy benzoate or tert-butyl peroxy isobutyrate, di-Ter
Dialkyl peroxides such as tert-butyl peroxide, digmyl peroxide and 1,3-bis(tert-butyl peroxy isopropyl)benben
1-bis(tert-butyl peroxy)-3.3.
5-trimethyl cyclohexane, 4,4-di-Ter
tert-butyl peroxyvaleric n-butyl ester, 2,2-bis(tert-butyl peroxy)
Perketal (Pe) such as butane or 2,2-bis(tert-butylperoxy)-4-methyl
In combination with hydroperoxides such as cumyl hydroperoxide or diisopropyl benzene hydroperoxide and ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide or cyclohexane peroxide. It can also be used as The novel peracid esters of the present invention can be prepared, for example, by reacting the corresponding acid chloride with 2,4,4-trimethylpentyl-2-hydroperoxide in the presence of a base such as pyridine, preferably in an organic solvent such as pentane. It can be obtained by

The invention will be illustrated by the following examples.

The term polyester as used in these examples is obtained by reacting 1 mole of phthalic anhydride and 1 mole of maleic anhydride with 2.1 moles of propylene glycol to the specified acid number by known methods. unsaturated polyester 6
Add 6 parts by weight of hydroquinone 0.01% and p-tert-butyl catechol 0.
．． A resin made with the addition of 33 parts of styrene containing 0.005% and is meant to be a "standard" resin intended for general purposes. Example 12,4,4-trimethylpentyl-
2-hydroperoxide (98.6%) 29.6t (0
．． After mixing 17.47 (0.22 mol) of pyridine and 100 ml of pentane, the mixture was cooled to 0°C.

21.27 (0.1 mol) of cyclohexane dicarboxylic acid dichloride was added to this mixture with stirring over a period of 1 hour at a temperature ranging from 0°C to 5°C, and then stirred for an additional 2 hours at the same temperature. . After washing the organic layer with water 507711 at about 3°C, the resulting aqueous layer was extracted with ethyl ether 20d. The organic layers were combined and then treated with water followed by 4N potassium carbonate solution (PO
tashlys) and then water.

In order to reduce the remaining hydroperoxides,
The organic solution was heated at room temperature for 1 hour in 30 ml of water with 3 f of sodium sulfite, 3 y of sodium acetate and 1.57 g of acetic acid.
Stir while mixing with the solution. After drying over MgSO42H2O crystals, remove the organic solvent under reduced pressure from 00 to 5 °C.
It was distilled off at

1,4-bis(2,4,4-trimethyl pentyl-2
-peroxycarbonyl)cyclohexane in an amount of 31.
It was collected as a semi-solid white material at 7t.

It contained 6.20% active oxygen. The yield calculated for active oxygen was 62%. 1. R. The carbonyl frequency of the (infrared) absorption spectrum is 1770C
T! It was L-1.

Similarly, by reacting 2,4,4-trimethylpentyl-2-hydroperoxide and 1,3-cyclohexane dicarboxylic acid dichloride,
4-Trimethylpentyl-2-peroxycarbonyl)cyclohexane was collected as a viscous clear liquid in 77% yield.

It contained 6.32% active oxygen. 1. R.
The carbonyl frequency of the absorption spectrum is 1771? It was -1.

2,4,4-trimethylpentyl-
2-hydroperoxide and 1,2-cyclohexane
Dicarboxylic acid dichloride is reacted to form 1,2-bis(2
- 4,4-Trimethylpentyl-2-peroxycarbonyl) cyclohexane was collected as a viscous transparent liquid with a yield of 73%.

1. R. The carbonyl frequency of the absorption spectrum is 1771
C7rL-1 Finally, 2,4,4-trimethylpentyl-2hydroperoxide and cyclohexane carboxylic acid chloride were reacted to produce 2,4,4-trimethyl-2-peroxy cyclohexane carboxylate in a yield of 83 % as a clear liquid.

It contained 5.66% active oxygen. 1. R.
The carbonyl frequency of the absorption spectrum is 1770 cwL-
It was 1.

Example 2 2,4,4-trimethylpentyl in 50y of pure styrene
After a 0.1y solution of 2-perhydrocyclohexane was introduced into the dilatometer, it was subsequently evacuated.

The dilatometer was placed in a constant temperature bath set at the polymerization temperature (80°C). Thereafter, the volume shrinkage during a period of time was observed and measured, and then the conversion and K, values were calculated sequentially. In the same manner, the K value p of other peracid esters of the present invention was measured.

The results are shown in the following table, where the K value of the corresponding tert-butyl perester is also shown for comparison.

Example 3 Polyvinyl alcohol [Elva
nOl) 50-42] 340 ml of 0.1% solution was charged.

After closing the autoclave, a vacuum was created inside it. Thereafter, 127 m9 of 2,4,4-trimethylpentyl-2-paoxycyclohexane carboxylate was dissolved in the contents of the autoclave.
711 was added.

The autoclave was kept at a temperature of 65°C for 11 hours. After the contents of the autoclave were cooled to room temperature, unconverted vinyl chloride was removed under reduced pressure. A white polymer 1747 was thus obtained, corresponding to a yield of 87%. Example 4 *(Unsaturated polyester resin prepared by adding a normal amount of styrene to an unsaturated polyester having an acid value of 20.

) Put the mixture into a mold with a diameter of 10.5 CI! L, height 3.2? and a round container with a wall thickness of 0.4 CTL was produced.

The polyester resin mixture was then applied to a pressure of 100 kg/
Ci! i and hot molding at temperatures in the range of 120 to 150°C.

The final product was measured for gloss and residual styrene. Gloss measurement is DIN (German Industrial Standard) 67
530. Residual styrene is B. A. S. F. B.A.S.F.
)'s Technical Billetant T. I. UP(Techn.
icalBulletinT. I. UP) 13d/82
859-1971.

Results for peracid esters of the present invention and corresponding Tert. −
The results for butyl perester are compared in the table below.

The amount of perester mixed into the polyester resin mixture was such that the percent active oxygen shown in the table was obtained. The peresters used are designated by the numbers used in the table of Example 2. Example 5 Polyester resin (acid value 3
The unsaturated polyester of No. 5 with the addition of a conventional amount of styrene) was thoroughly mixed with 2.4.4-1.dimethyl pentyl-2-peroxy cyclohexane carboxylate 1r.

To this mixture was added a metal compound in an amount of 1% by weight, calculated on the total amount of the mixture. The metal compound used was Fe2O3 (
Eisenoxidosh Waltz U4l3 [EisenO
xid-SchwarzU4l3]) and cobalt-2-ethylhexanoate solution in dioctyl phthalate (
CO1% content).

The polyester resin mixture was subsequently cured at 60°C and gel time, minimum cure time and peak exotherm were measured. The gelation time is determined when the temperature of the polyester resin mixture 25V in a test tube placed in a constant temperature bath at 60°C is 25°C.
(i.e. from 45°C to 70°C).

The minimum curing time is the maximum temperature that the same amount of polyester resin mixture can reach from 45°C, the so-called maximum exotherm,
It should be understood that it is the time until The results are shown in the table below.

Claims (1)

[Claims] 1. In a method for producing a new peracid ester suitable for initiating a radical reaction, the following formula ▲ includes mathematical formulas, chemical formulas, tables, etc. ▼ (in the formula, n is 1 or 2) The above-mentioned method is characterized in that it is produced by reacting a peracid ester having the following formula with a hydroperoxide having the following formula: