JP3214955B2 - New polymerization initiator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel vinyl monomer polymerization initiator comprising a peracid ester, and more particularly to a vinyl chloride monomer or a monomer copolymerizable with a vinyl chloride monomer. (Hereinafter abbreviated as vinyl chloride monomer).

[0002]

2. Description of the Related Art When polymerizing vinyl chloride monomers, tert-butyl peroxypivale is used as a polymerization initiator.
G, tert-butyl peroxy neodecanoate,
It is already known that di-2-ethylhexyl peroxydica carbonate and the like are used. The 10-hour half-life temperature of these polymerization initiators (the temperature at which the concentration of a 0.1 molar solution in benzene becomes half in 10 hours) is 40 to 60 ° C.
It falls within the range. Recently, vinyl chloride resin
Car companies are actively reducing the polymerization time in order to streamline production. In order to satisfy these requirements, the amount of the polymerization initiator having a 10-hour half-life temperature of 40 to 60 ° C. must be considerably increased. However, when the amount used is increased, the thermal stability of the obtained polymer deteriorates.

As a polymerization initiator having a 10-hour half-life temperature of 40 ° C. or less, α-cumylperoxy neodecanoate (C
ND), acetylcyclohexylsulfonyl peroxide (abbreviated to ACSP) and the like are known. However, α-cumyl peroxy neodecanoate has a drawback that its low-temperature activity is not sufficient, and acetylcyclohexylsulfonyl peroxide has a poor thermal stability of the obtained polymer.

[0004]

The problem to be solved by the present invention is to start a new low-temperature active polymerization which can shorten the polymerization time of the vinyl chloride monomer and does not impair the thermal stability of the obtained polymer. Finding the drug.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, when a peracid ester having a specific structure is used as an active ingredient, the above problems have been solved. The inventors have found that the present invention has been completed. That is, a polymerization initiator of a vinyl chloride monomer containing a peracid ester represented by the general formula 1 as an active ingredient,

Embedded image The polymerization initiator for a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (2):

Embedded image 2. The polymerization initiator for a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (3).

Embedded image The polymerization initiator of a vinyl chloride-based monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (4).

Embedded image The polymerization initiator of a vinyl chloride-based monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (5).

Embedded image The polymerization initiator for a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (6).

Embedded image

The peracid ester of the present invention has the general formula 1
As shown in the above, a branched alkyl group having 7 to 9 carbon atoms and a branched or linear alkyl group having 1 to 3 carbon atoms including a tert-butyl group at a carbon atom (α-carbon) adjacent to the carbonyl group Is a peroxyester of neoacid having 13 carbon atoms in total including carbonyl carbon, and is a novel compound not described in any literature.

The present inventors have found that this peroxyester is much lower temperature active than the known tertiary peroxyester. That is, tert-hexylperoxy-2-isopropyl-2,3,5,5-
Tetramethylhexanoate (abbreviated as TH-IX)
Has a 10-hour half-life of 38 ° C., tert-octylperoxy-2,2,8,8-tetramethylnonanoate (abbreviated as TO-MN) has a 10-hour half-life of 37 ° C.
Tert-amylperoxy-2-isopropyl-
2,6,6-Trimethylheptanoate (abbreviated as TA-IP) has a 10-hour half-life of 38 ° C., tert-hexylperoxy-2-propyl-2,6,6-trimethylheptanoate. (TH-PP) has a 10-hour half-life of 38 ° C. and tert-octylperoxy-2-ethyl-2,7,7-trimethyloctanoate (TO-EO).
) Was 38 ° C. On the other hand, the already known tert-hexyl peroxyneodecanoate (TH-ND) has a 10-hour half-life of 42 hours.
° C, cumyl peroxy neodecanoate (CND) is 3
9 ° C. Therefore, the polymerization initiator of the present invention is a practical and very effective polymerization initiator which meets the above-mentioned object of streamlining the production of vinyl chloride resin.

[0008] The polymerization initiator of the present invention is a peracid ester represented by the general formula 1.

Embedded image The peracid ester represented by the general formula 1
As specific examples of the peracid ester represented by
Shari-amyl peroxy-2-isopropyl-2,
3,5,5-tetramethylhexanoate, tert-hexylperoxy-2-isopropyl-2,3,3
5,5-tetramethylhexanoate, tert-octylperoxy-2-isopropyl-2,3,5,5
-Tetramethylhexanoate, tert-dodecylperoxy-2-isopropyl-2,3,5,5-tetramethylhexanoate, cumylperoxy-2-isopropyl-2,3,5,5- Tetramethylhexanoe
Specific examples of peracid esters represented by the general formula 3 include tert-amylperoxy-2,2,8,8-tetramethylnonanoate and tert-amylperoxy-2,2,8,8-tetramethylnonanoate. -Hexylperoxy-2,2,8,8-tetramethylnonanoate, tert-octylperoxy-
2,2,8,8-tetramethylnonanoate, tert-dodecylperoxy-2,2,8,8-tetramethylnonanoate, cumylperoxy-2,2,8,8-
Specific examples of the peracid ester represented by the general formula 4 include tert-amylperoxy-2-isopropyl-2,2 and tetramethylnonanoate.
6-trimethylheptanoate, tert-hexylperoxy-2-isopropyl-2,2,6-trimethylheptanoate, tert-octylperoxy-
2-isopropyl-2,2,6-trimethylheptanoate, tert-dodecylperoxy-2-isopropyl-2,2,6-trimethylheptanoate, cumylperoxy-2-isopropyl-2,2 , 6-trimethylheptanoate and the like. Specific examples of the peracid ester represented by the general formula 5 include tertiary esters.
Amyl peroxy-2-propyl-2,2,6-trimethylheptanoate, tert-hexylperoxy-2-propyl-2,2,6-trimethylheptanoe-
G, tert-octylperoxy-2-propyl-
2,2,6-trimethylheptanoate, tertiary
Dodecyl peroxy-2-propyl-2,2,6-trimethylheptanoate, cumylperoxy-2-propyl-2,2,6-trimethylheptanoate, and the like, are represented by the general formula (6). Specific examples of peracid esters include tertiary-amylperoxy-2-ethyl-
2,7,7-trimethyloctanoate, tertiary
Hexylperoxy-2-ethyl-2,7,7-trimethyloctanoate, tert-octylperoxy-2-ethyl-2,7,7-trimethyloctanoe-
G, tert-dodecylperoxy-2-ethyl-
2,7,7-trimethyloctanoate and cumylperoxy-2-ethyl-2,7,7-trimethyloctanoate.

The peracid ester of the present invention is synthesized as follows. That is, 2-isopropyl-2,3,5,5-tetramethylhexanoic acid chloride, 2,2,8,8-tetramethylnonanoic acid chloride, 2-isopropyl-2,
2,6-trimethylheptanoic chloride, 2-propyl-2,2,6-trimethylheptanoic chloride, 2
-Ethyl-2,7,7-trimethyloctanoic acid chloride alone or in admixture with tert-hexyl hydroperoxide, tert-octyl hydroperoxide, tert-dodecyl hydroperoxide, cumyl hydroperoxide It can be obtained by reacting each alone or a mixture thereof with sodium hydroxide or potassium hydroxide as a catalyst under the same reaction conditions as ordinary peresters. In addition, the compound is synthesized using a diluent of an aromatic hydrocarbon (eg, toluene, ethylbenzene) or an aliphatic hydrocarbon (eg, hexane, octane, mineral spirit, isoparaffin, etc.), or is used after being diluted after the synthesis. Can be done.

The acid chloride used in the present invention is 2-isopropyl-2,3,5,5-tetramethylhexanoic acid, 2,2,8,8-tetramethylnonanoic acid, 2-isopropyl-2,2,2 6-trimethylheptanoic acid, 2-propyl-2,2,6-trimethylheptanoic acid, 2-ethyl-2,7,7-trimethyloctanoic acid alone or in a mixture of phosphorus trichloride, phosphorus oxychloride, thionyl chloride and phosgene After the addition of a chlorinating agent and the like, the reaction can be performed by isolating the acid chloride product from the reaction mixture. The structure of the acid used as a raw material of the acid chloride was confirmed by the following acid value, IR and NMR data.

The acid value of the acid used in the present invention is 2
It shows a value of 58-260 KOHmg / g, which is in good agreement with the theoretical acid value of an acid having 13 carbon atoms of 262 KOHmg / g. IR data
In each case, the strong absorption of the carbonyl group near 1600 cm @ -1 and the absorption of the hydroxyl group near 3000 cm @ -1 indicate that the acid is an acid having 13 total carbon atoms together with the acid value data. . NMR data supports its structure as shown in FIGS.

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

The polymerization initiator containing a peracid ester of the present invention is mainly used for the polymerization of a vinyl chloride monomer, and other vinyl monomers copolymerizable with the vinyl chloride monomer include:
Examples include ethylene, vinyl acetate, vinylidene chloride, styrene, acrylates, and methacrylates.

The polymerization initiator containing a perester of the present invention may be another organic peroxide-based polymerization initiator such as tert-butyl peroxy neodecanoate or tert-amyl peroxy pivalate. Tert-amyl peroxy neodecanoate, tert-hexyl peroxy neodecanoate, tert-hexyl peroxy neodecanoate, tert-octyl peroxy pivalate,
Peroxyesters such as tert-octyl peroxy neodecanoate, peroxy dicarbonates such as di-2-ethylhexyl peroxy dicarbonate and di-1-methyl heptyl peroxy dicarbonate. And diacyl peroxides such as dioctanoyl peroxide, diisononanoyl peroxide, dilauroyl peroxide and the like.

[0014]

By using the polymerization initiator containing a peracid ester of the present invention, the polymerization time is shortened, the productivity is improved, and the thermal stability of the resin obtained by the polymerization is also greatly improved.

[0015]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

[0016]

Example 1 (Synthesis of 2-isopropyl-2,3,5,5-tetramethylhexanoic acid chloride) 214 g of a mixture of 2-isopropyl-2,3,5,5-tetramethylhexanoic acid was placed in a 500 ml four-necked round-bottom flask equipped with a thermometer and a cooling tube with a drying tube, and 143 g of thionyl chloride was added at room temperature with stirring. . Under stirring, the liquid temperature was raised to 60 ° C., and the reaction was continued for 4 hours. Thereafter, unreacted thionyl chloride was distilled off under reduced pressure to obtain 231 g of acid chloride. This had a chlorine content of 15.2% and a calculated purity of 99.8%. This is used for the synthesis of the following peresters.

(Tert-hexylperoxy-2-)
Synthesis of isopropyl-2,3,5,5-tetramethylhexanoate) A 200 ml four-necked flask equipped with a stirrer was charged with 41.7 g of a 35% aqueous potassium hydroxide solution, and the mixture was stirred while maintaining the liquid temperature at 15 ° C. , 98% tert-hexyl hydroperoxide are added. Further, 46.7 g of 2-isopropyl-2,3,5,5-tetramethylhexanoic acid chloride obtained above is added dropwise while maintaining the liquid temperature at 20 ° C. After continuing the reaction at 20 ° C. for another 3 hours, 50 ml of cold water is added and the mixture is allowed to stand for liquid separation. The oil layer was washed with 70 g of a 5% aqueous sodium hydroxide solution, and then washed three times with water. Anhydrous magnesium sulfate was added to the obtained oil layer, and the mixture was stirred, dried, filtered, and filtered to obtain 49.6 g of a colorless and transparent liquid tert-hexylperoxy-2-isopropyl-2,3,5,5-tetramethylhexa. Noet (TH-IX) was obtained. Active oxygen content is 4.84%
Was 95% and the yield was 75%.

[0018]

EXAMPLE 2 The hydroperoxide of Example 1 was replaced with tert-octyl hydroperoxide (98% purity).
The reaction was carried out in the same manner as in Example 1 except that the acid chloride was replaced with 46.7 g of 2,2,8,8-tetramethylnonanoic acid chloride instead of 8 g.
2,2,8,8-tetramethylnonanoate (TO-M
N) 56.6 g were obtained. The active oxygen content was 4.30%, the purity was 92%, and the yield was 76%.

[0019]

EXAMPLE 3 The hydroperoxide of Example 1 was replaced with tert-amyl hydroperoxide (99% purity), 22.1.
g instead of 2-isopropyl-2,6,2
The reaction was carried out in the same manner as in Example 1 except that 46.7 g of 6-trimethylheptanoic acid chloride was used. 51.6 g of tert-amyl peroxy-2-isopropyl-2,6,6-trimethylheptanoate (TA-IP) were obtained.
The active oxygen content was 5.06%, the purity was 95%, and the yield was 85%.

[0020]

EXAMPLE 4 The hydroperoxide of Example 1 was replaced with tert-hexyl hydroperoxide (98% purity).
4 g, acid chloride was replaced with 2-propyl-2,6,6
The reaction was carried out in the same manner as in Example 1 except that 46.7 g of trimethylheptanoic acid chloride was used. 50.3 g of tert-hexylperoxy-2-propyl-2,6,6-trimethylheptanoate (TH-PP) was obtained. The amount of active oxygen was 4.73%, the purity was 93%, and the yield was 80%.

[0021]

Example 5 The hydroperoxide of Example 1 was replaced with tert-octyl hydroperoxide (98% purity).
8 g, and acid chloride was replaced with 2-ethyl-2,7,7-
The reaction was carried out in the same manner as in Example 1 except that 46.7 g of trimethyloctanoic acid chloride was used. There was obtained 53.4 g of tert-octylperoxy-2-ethyl-2,7,7-trimethyloctanoate (TO-EO). The active oxygen content was 4.20%, the purity was 90%, and the yield was 90%.
The 10-hour half-life temperatures of the peroxyesters of Examples 1 to 5 were as shown in Table 1 below.

[Table 1]

[Polymerization Example 1] 1 g of partially saponified polyvinyl alcohol and 3000 g of ion-exchanged water were charged into a 5 l stainless steel autoclave having a stirrer, and dissolved by stirring well. Tert-octylperoxy-2,
8,8,8-Tetramethylnonanoate (TO-MN)
0.95 g and tert-butyl neodecanoate 0.1 g
1500 g of a vinyl chloride monomer in which 10 g was dissolved were press-fitted. While stirring, the internal temperature was raised to 50 ° C. to carry out polymerization. In 4 hours, the internal pressure is 4.5 kg / cm ² above the equilibrium pressure.
Dropped. At this time, the polymerization slurry was taken out, and the obtained polymer was filtered and dried. The conversion was 90%.

[Polymerization Example 2] 1 g of partially saponified polyvinyl alcohol and 3000 g of ion-exchanged water were charged into a 5 l stainless steel autoclave having a stirrer, and dissolved by stirring well. Dissolve 1.0 g of tert-hexylperoxy-2-isopropyl-2,3,5,5-tetramethylhexanoate (TH-IX) and 0.10 g of tert-butyl neodecanoate 1500 g of the obtained vinyl chloride monomer was press-fitted. While stirring, the internal temperature is 50 ℃
And the polymerization was carried out. After 4 hours, the internal pressure was lower than the equilibrium pressure by 4.5 kg / cm ² . At this point, the polymerization slurry
Was taken out, and the obtained polymer was filtered and dried. The conversion was 90%.

Since the thermal stability of the vinyl chloride resin significantly appears in the initial coloring of the resin, an initial coloring test was performed. The results of the initial coloring test are shown in Table 2 together with polymerization examples and comparative examples.

[Initial coloring test] 100 g of vinyl chloride resin
Then, 50 g of dioctyl phthalate and 2.5 g of dibutyltin maleate were mixed and kneaded at 160 ° C. for 7 minutes, and the coloring of the sheet was visually observed.

[0026]

Comparative Example 1 Polymerization was carried out by changing the peroxide in the polymerization example to 0.94 g of α-cumylperoxy neodecanoate (CND) and 0.35 g of di-2-ethylhexyl peroxydica-bonate. After 7 hours, the internal pressure is 4.5 kg /
m ³ decreased. The conversion was 91%.

[0027]

COMPARATIVE EXAMPLE 2 0.68 g of acetylcyclohexylsulfonyl peroxide (ACSP) was added to the peroxide of the polymerization example.
Di-2-ethylhexyl peroxydica carbonate 0.3
The polymerization was carried out with the amount changed to 5 g. In 4 hours, the internal pressure dropped 4.5 kg / m ³ from the equilibrium pressure. The conversion was 90%.

Table 2 shows the results of the polymerization test and the initial coloring test.

[Table 2]

Continuation of the front page (56) References JP-A-5-105708 (JP, A) JP-A-4-198306 (JP, A) JP-A-3-45603 (JP, A) JP-A-3-35006 (JP) , A) JP-A-58-120614 (JP, A) JP-A-57-139104 (JP, A) JP-B-49-28908 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB Name) C08F 4/32-4/38 CA (STN) REGISTRY (STN)

Claims (6)

(57) [Claims] 1. A polymerization initiator for a vinyl chloride monomer, comprising a peracid ester represented by the general formula 1 as an active ingredient. Embedded image 2. The polymerization initiator for a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the general formula (2). Embedded image 3. The polymerization initiator of a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the following general formula (3). Embedded image 4. The polymerization initiator of a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the following general formula 4. Embedded image 5. The polymerization initiator of a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the following general formula (5). Embedded image 6. The polymerization initiator of a vinyl chloride monomer according to claim 1, wherein the structure of the peracid ester is represented by the following general formula (6). Embedded image