JPH0240362A - Diacyl type polymeric peroxide - Google Patents

Abstract

NEW MATERIAL:Diacyl type polymeric peroxides of the formula (X is -H, -Cl, -O-CH3, etc., in n=1; m=2-15). USE:Radical polymerization initiators for ethylenic unsaturated monomers (e.g., styrene, vinyl acetate). Useful as polymerization initiators for production of an expandable polystyrene, impact-resistant polystyrene or block copolymer. PREPARATION:A mixture of 7,12-dimethyloctadecane-7,11-diene-1,18-dicarboxylic acid chloride and a monobasic chloride corresponding to end groups of a compound of the formula is gradually added to an aqueous solution of a peroxidation agent such as a sodium peroxide or potassium peroxide with stirring and reacted to obtain the compound of the formula. The mole ratio of the monobasic acid based on the dicarboxylic chloride as the raw material is 1:(0.07-1).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a novel diacyl type polymeric peroxide. It is also a diacyl-type polymeric peroxide that is effective as a free radical polymerization initiator (hereinafter abbreviated as polymerization initiator) for ethylenically unsaturated monomers.

(Prior art) Conventionally, diacyl-type polymeric peroxides obtained by polycondensation reaction of tribasic acid chlorides and peroxides,
Gesellschaft, Volume 27, Page 1510 (1894
), and diacyl-type polymeric peroxides obtained from the reaction of linear saturated tribasic acid chlorides with sodium peroxide are published in Chemical Abstracts, Vol. 60, 52.
93d (1940).

These diacyl type polymeric peroxides have the drawback of being sensitive to impact and friction, and having little or no solubility in various organic solvents and ethylenically unsaturated monomers.

In order to solve these drawbacks, diacyl-type polymeric peroxides having a branched long-chain hydrocarbon group as a constituent unit in the molecule have been proposed in JP-A-59-8726, JP-A-59-176320, and JP-A-59-176320. This was proposed in Publication No. 59-38233.

However, these diacyl-type polymeric peroxides do not have sufficient initiator efficiency, and like conventional ones, they are obtained by the reaction of a tribasic acid chloride and a peroxidant, so their terminal groups are group or carboxylic acid group, and there remained a problem in stability over time.

In order to solve these drawbacks, a diacyl type polymeric peroxide having a specific terminal group represented by the following formula, namely (where X is -H, -CI when n is 1, -0-Cf1
3. -m-CH,.

CH2CH3, -C(CH3)3, when n is 2, C1 at the 2.4th position is shown, and m is 2 to 15) is disclosed in Japanese Patent Publication No. 63-15267, and
No. 15268 (in the formula, X represents an alkyl group having 1 to 19 carbon atoms, and n
is 2 to 15) is disclosed.

Problems to be Solved by the Invention The diacyl-type polymeric peroxides having the specific terminal groups described above have improved safety, solubility, initiator efficiency, and especially oral stability. However, these diacyl-type polymeric peroxides are still not sufficient in terms of initiator efficiency, and from the viewpoint of cycle-up during polymerization, even higher diacyl-type polymeric peroxides are desired. Ta.

As a result of various studies conducted by the inventors in order to solve this drawback, the inventors discovered that a new diacyl type polymeric peroxide, which has a hydrocarbon group branched at two locations within the molecule in the structural unit, and a specific terminal group. The present inventors have discovered that a novel diacyl-type polymeric peroxide having the following properties improves initiator efficiency without deteriorating oral stability, solubility, or even safety, leading to the completion of the present invention.

(Means for solving the problem) The present invention is based on the following general formula (wherein, when n is 1, X is -H, -CI, -CH3, -
CH2CH3°C(CH,)3, when n is 2,
-C1 at the 2.4-position, m is 2 to 15) This is a novel diacyl type polymeric peroxide.

The novel diacyl-type polymeric peroxide of the present invention is represented by the above-mentioned general formula, and the type and number of substituents represented by Xn on both terminal benzene rings in the formula may be the same or different. good.

The novel diacyl type polymeric peroxide of the present invention can be produced, for example, as follows.

That is, a mixture of 7,12-dimethyloctadecane-7,11-diene-1,18-dicarboxylic acid chloride and a monobasic acid chloride corresponding to the terminal group of formula (1) above is heated with sodium peroxide or peroxide. Add it little by little to an aqueous solution of a peroxidant such as potassium oxide while stirring and let it react, and after the reaction is complete,
It can be easily produced by separating it from the reaction waste liquid.

7.12-dimethyloctadecane-7,11-diene-
The molar ratio of monobasic acid to 1,18 dicarboxylic acid chloride is 0.07 to 1, assuming that the former is 1. 0.07
If m (average degree of condensation) is less than 15, m (average degree of condensation) will be greater than 15, but a peracid group or a carboxylic acid group will remain at the end group of the peroxide, which will have an adverse effect on stability over time. Moreover, when it exceeds 1, the specific effect as a hepolymeric peroxide cannot be exhibited due to the by-product of normal monofunctional diacyl peroxide.

The amount of peroxidant used is about 0.5 to 1.5 equivalents based on the amount of chlorine in the mixture of raw oxides.

The reaction conditions are ordinary diacyl peroxide and In, and the reaction temperature is about -10 to 40°C, preferably about -5 to -15°C.
℃, and the reaction time is about 0.1 to 5 hours, preferably about 0.
．． 25 to 2 hours.

The novel diacyl-type polymeric peroxide of the present invention produced as described above is a colorless and transparent liquid.

In this diacyl type polymeric peroxide, the C=OM combination of diacyl and the 0-0 bond of the peroxide were confirmed by infrared absorption spectrum, and the -CH,, -CH2, -CH, -COCH2- configuration was confirmed by nuclear magnetic resonance spectrum. ), the average molecular weight is determined, and the average degree of condensation m is determined from that value.

Furthermore, the amount of active oxygen is determined by iodometric titration.

This diacyl type polymeric peroxide is useful as a polymerization initiator for ethylenically unsaturated monomers. Examples of the ethylenically unsaturated monomer include styrene, vinyl acetate, acrylic ester, methacrylic ester, acrylonitrile, methacrylic acid, vinylidene chloride, and vinylidene chloride. It is also useful as a polymerization initiator for the production of expanded polystyrene, high impact polystyrene or block copolymers.

(Effects of the Invention) The novel diacyl-type polymeric peroxide of the present invention has a branched hydrocarbon group in the molecule, and has an equally excellent aging property compared to the conventional diacyl-type polymeric peroxide that has a specific terminal group. It has stability, and further increases initiator efficiency, making it possible to cycle up during polymerization.

In addition, like conventional diacyl-type polymeric peroxides having a branched hydrocarbon group in the molecule, they have excellent solubility in organic solvents and ethylenically unsaturated monomers. When used as a polymerization initiator, its workability can be greatly improved. In addition, it is 1 to 3 times more resistant to impact and friction than conventional diacyl-type polymeric peroxide, and has very high stability during handling. Furthermore, when used as a polymerization initiator for ethylenically unsaturated monomers, the molecular weight is approximately twice as high as that of conventional diacyl type polymeric peroxides compared to when ordinary monofunctional diacyl peroxides are used. A polymer having the following properties is obtained.

(Example) Next, the diacyl type polymeric peroxide of the present invention will be described in more detail with reference to Examples.

Example 1 166 g (0.29 mol) 50% 7% aqueous sodium hydroxide solution in a four-bottle flask equipped with a stirrer and a thermometer
9.9 g (0,145 mol) of hydrogen peroxide solution was mixed to prepare m aqueous sodium peroxide solution. Then 7,12-
Dimethyloctadecane-7,11-diene 1,18-dicarboxylic acid chloride (99% purity) 40.8g (0,1
A mixture of 5.6 g (0.04 mol) of benzoic acid chloride and 50 g of toluene was added in portions under stirring at a temperature of 0 to 5°C.

After stirring at this temperature for 30 minutes, the mixture was neutralized to pH 7 with dilute hydrochloric acid. The organic layer was then taken out, washed twice with water, and then dried over anhydrous magnesium sulfate. Solid matter was removed by filtration, and toluene was distilled off under reduced pressure to obtain 35 g of a colorless and transparent liquid.

The active oxygen content of this tone liquid was determined to be 4.19% by the usual iodometric titration method.

The characteristic absorption wavelengths in the infrared absorption spectrum of this tone liquid are 1780 cm-', 1810 cm-' (C=O bond of diacyl group) and 890 am-' ([1-[1
bond), and based on the carboxylic acid group, absorption at 1710 cm-' due to C=0 bond and absorption at 2600 cm-' due to DH bond.
Absorption at ~3200 cm', absorption at 1750 cm-' due to <C·0 bond based on peracid groups, and absorption at 3300 cm-' due to DH bond were not observed. The δ value and intensity of the nuclear magnetic resonance absorption spectrum are (a) 1.20
ppm (60H) (b) 1.511) pm (20H) (c) 1.65 ppm (30) 1) (d) 2.0
1 ppm (408) (e) 2.18 ppm (2ON) (f) 5.10 ppm (10ft) (g) 7.3
6 flpm (6H) (h) 7.90 ppm (4H), and the average molecular weight measured by the vPO method is 2064
Therefore, it was confirmed that it was a diacyl type polymeric peroxide represented by the following formula.

■■ Examples 2-9 Monobasic acid chloride and 7% sodium hydroxide and 50%
Diacyl type polymeric peroxide was produced in the same manner as in Example 1, except that the amount of hydrogen peroxide solution was changed to the amount shown in Table 1 below, and its structure was confirmed in the same manner as in Example 1. did. The results are shown in Table 2.

Comparative Example 1 7.12-dimethyloctadecane-7,11-diene-
A known diacyl type polymeric peroxide was produced by reacting 1°18-dicarboxylic acid chloride with sodium peroxide. This peroxide was confirmed to be a peroxide consisting of the structural unit of the following formula from the characteristic absorption wavelength of the infrared absorption spectrum and the δ value and intensity of the nuclear magnetic resonance spectrum. The average molecular weight is 7600 from the measurement results by vPO method.
(average degree of condensation 20.8).

Comparative Example 2 A known diacyl-type polymeric peroxide was produced by reacting a mixture of 7-ethylhexadecane-1,16-dicarboxylic acid chloride and benzoic acid chloride (molar ratio 5:2) with sodium peroxide. This peroxide was confirmed to be a peroxide consisting of the structural unit of the following formula from the characteristic absorption wavelength of the infrared absorption spectrum and the δ value and intensity of the nuclear magnetic resonance spectrum. The average molecular weight is 1990 from the measurement results by the VPO method.
(average degree of condensation 5.1).

Reference Example 1 [Polymerization of styrene (bulk polymerization) and measurement of polymerization initiator efficiency] 0.02 mol of the diacyl type polymeric peroxide produced in Examples 1 to 9 and Comparative Example 1.2 was added to each 11 styrene as a polymerization initiator. 5 m of sample prepared by dissolving each
1l! was sealed in a glass ampoule with an inner diameter of 12 mm, and 6
Polymerization was performed at 0°C, and the initiator efficiency was determined for each polymerization initiator.

The initiator efficiency was measured based on the method described in "Vinyl Polymerization Experimental Method" (Kyoritsu Shuppan), page 256.

- The measurement results obtained for each are shown in Table 3 below.

Table 3 above clearly shows that the diacyl type polymeric peroxide of the present invention has superior initiator efficiency compared to the conventional diacyl type polymeric peroxide.

Reference Example 2 [Polymerization of styrene (bulk polymerization) and measurement of average molecular weight] 5 ml of a sample prepared by dissolving 0.09 mole of the diacyl type polymeric peroxide produced in Example 1 as a polymerization initiator in styrene 1β was mixed with an inner diameter of 12 + nm. The mixture was sealed in a glass ampoule, and polymerization was carried out at 70°C for 7 hours. After that, the reaction solution was taken out and dissolved in 50-benzene,
The polymerization conversion rate was determined by quantifying unreacted styrene monomer by gas chromatography using an internal standard method.

Then, the mixture was poured into 500 ml of methyl alcohol to precipitate a white polystyrene precipitate. After drying this white precipitate, the average molecular weight of the polystyrene was determined by GPC (high performance liquid chromatograph model HLC-802UR manufactured by Toyo Soda Kogyo ■).

For comparison, ordinary lauroyl peroxide was used in place of the diacyl type polymeric peroxide, and the same operation was performed to determine the polymerization conversion rate and the average molecular weight of polystyrene. These results are shown in Table 4 below.

As is clear from Table 4 above, the diacyl-type polymeric peroxide of the present invention can approximately double the average molecular weight of styrene compared to conventionally used lauroyl peroxide, making it an excellent polymerization initiator. It shows that

Reference Example 3 [Stability over time, safety, solubility] Regarding the diacyl-type polymeric peroxides produced in Example 1 and Comparative Examples 1 and 2, the stability over time, safety, and solubility in various solvents were evaluated using the following method. It was measured. The obtained results are shown in Tables 5, 6 and 7 below, respectively.

=Daily stability= It was determined as the decomposition rate after 25 days, 50 days, and 100 days at 5°C. Similarly, after 10 days at 5℃, 2
The decomposition rate was determined after 0 days and 30 days.

-Safety test = Drop sensitivity, friction sensitivity, ballistic mortar, and pressure vessel tests were conducted using the methods described in "Safety Engineering", Vol. 4, No. 2, p. 181 (1965).

1 Solubility test = The number of grams dissolved in 100 grams each of benzene, toluene, styrene, chloroform, and ethyl acetate at 25° C. was measured.

As is clear from the above-mentioned Tables 5, 6, and 7, the diacyl-type polymeric peroxide of the present invention has no difference in oral stability and solubility compared to conventional diacyl-type polymeric peroxides, Furthermore, it can be seen that there is a slight improvement in safety.

Claims (1)

[Claims] 1. The following general formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, when n is 1, X is -H, -Cl, -o-CH_3
, -m-CH_3, -CH_2CH_3, -C(CH_
3) A novel diacyl-type polymeric peroxide represented by _3, when n is 2, it represents -Cl at the 2 and 4 positions, and m is 2 to 15).