JP3158178B2 - Polymerization method of vinyl chloride monomer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention relates to the initiation of polymerization of a specific peroxyester alone or a specific peroxyester with a specific peroxide having a half-life temperature of 10 hours (hereinafter abbreviated as half-life temperature) of 43 to 65 ° C. When used as an agent, when polymerizing vinyl chloride monomers, the amount of vinyl chloride monomers used is small, the polymerization time can be shortened, the odor during processing is small, and the color of processed products is also improved. It relates to a polymerization method.

[0002]

2. Description of the Related Art In a manufacturer of vinyl chloride, an organic peroxide capable of shortening the polymerization time has been demanded in order to improve the productivity of a general-purpose resin. For example, dialkyl peroxy dicarbonates such as diisopropyl peroxy dicarbonate and di-2-ethylhexyl peroxy dicarbonate.
Bones (half-life temperature of 40 ° C. to 45 ° C.) are used as a polymerization initiator of vinyl chloride, but the color of processed products is inferior. Also, conventionally used peroxyesters such as tert-butyl peroxypivalate and tert-butyl peroxy neodecanoate have too high a half-life temperature and a high polymerization rate can be obtained in a short time. Absent.

On the other hand, cumyl peroxy neodecanoate has a half-life temperature of 38 ° C. and is used to shorten the polymerization time because of its low-temperature decomposability, but it is close to acetophenone or phenol during processing of the polymer. There is a disadvantage that the decomposition product has a strong odor.

Various attempts have been made for these improvements. For example, Japanese Patent Publication No. 58-120613 discloses tertiary octylpa-oxyneodecanoe.
It has been proposed that a polymer using a polymer can obtain an odorless vinyl chloride polymer during processing. However, there is a disadvantage that the polymerization is not completed unless a large amount of the polymerization initiator is used.

In order to improve the productivity, a method has been proposed in which an initiator having a low half-life temperature and an initiator having a high half-life temperature are combined to make the polymerization rate uniform and improve the productivity in order to keep the polymerization rate constant. ing.

For example, JP-B-46-14670 uses a combination of acetylcyclohexylsulfonyl peroxide and a dialkyl peroxydica-bonate having a high half-life temperature as an initiator having a low half-life temperature. However, when acetylcyclohexylsulfonyl peroxide is used in a large amount, there is a disadvantage in that the thermal stability of the vinyl chloride polymer deteriorates.

[0007] Japanese Patent Application Laid-Open No.
Japanese Patent No. 149407 uses a combination of cumyl peroxy neodecanoate and a dialkyl peroxy dicarbonate. However, in the case of this combination, when cumyl peroxy neodecanoate is used, a plasticizer or the like is added and kneaded to produce a processed product. There is.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to reduce the amount of a polymerization initiator used, shorten the polymerization time, improve productivity, and use a plasticizer or the like to obtain a resin obtained by polymerization. It is an object of the present invention to propose a polymerization method using a polymer initiator which can be added to produce a processed product, in which the odor due to the decomposition product of the organic peroxide is small and the color of the processed product is also improved.

[0009]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted intensive studies on a method for polymerizing vinyl chloride monomers using various organic peroxides. 1,2,2-trimethylpropylperoxyneodecanoate represented by the general formula (1) and (B) a half-life temperature of 43 ° C to a half-life temperature of tert-butylperoxyneodecanoate or less (48 ° C) )
Dialkyl peroxydicarbonate and peroxide
The present inventors have found a method for polymerizing a vinyl chloride-based monomer using a polymerization initiator mixed with at least one selected from xyesters, and have completed the present invention.

Embedded image (R1, R2, and R3 are each an alkyl group having 1 or more carbon atoms, and the total number of those carbon atoms is 8.)

According to the present invention, the component (A) has a low half-life temperature (41.5 ° C.) and uses a smaller amount of the polymerization initiator than the existing tertiary-alkyl peroxyester polymerization initiator. It is considered that the coloring and the odor of the polymer were improved, and the combination of the component (A) and the component (B) stabilized the polymerization rate and shortened the polymerization time.

The component (B) used in the present invention includes:
Dialkyl peroxy dicarbonates such as di-2-ethylhexyl peroxy dicarbonate, di-1-methylheptyl peroxy dicarbonate, dimyristyl peroxy dicarbonate, dioctyl peroxy dicarbonate, dilauryl peroxy dicarbonate, and tertiary butyl peroxy neodecanoate peroxy esters and the like are exemplified.

When the half-life temperature is higher than 65 ° C., it is difficult to shorten the polymerization time with a small amount of initiator. On the other hand, when the half-life temperature is lower than 43 ° C., it is difficult to make the polymerization rate uniform.

In the present invention, the amount of a general polymerization initiator used in the polymerization of a vinyl chloride monomer is 10
0.005 to 0.5 parts by weight per 0 parts by weight. 0.0
If the amount is less than 05 parts by weight, the polymerization rate becomes extremely slow. If the amount exceeds 0.5 parts by weight, the polymerization reaction occurs rapidly and it becomes difficult to control the temperature.

In the present invention, the mixture molar ratio of the component (A) and the component (B) is used in the range of 1.0: 0.1 to 1.0: 10.0. Outside this range, it is difficult to achieve the object of the present invention.

Examples of the vinyl chloride in the present invention include vinyl chloride and vinylidene chloride.

The polymerization of vinyl chloride monomer in the present invention includes copolymerization with other copolymerizable vinyl monomers such as ethylene, vinyl acetate, vinylidene chloride, styrene and acrylates.

The component (A) used in the present invention is produced by a general method for producing peroxyesters.
As an example, tert-hexyl hydroperoxide and neodecanoic acid chloride (neodecanoyl chloride manufactured by BASF) in the presence of 5 to 40% by weight of an alkali metal hydroxide is -10 to -10. It is produced by reacting at 30 ° C.

[0018]

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the embodiments.

The initiators used in the Examples and Comparative Examples all had a concentration of 70% by weight (diluent: isoparaffin).

Reference Example 1 In a 5-liter stainless steel autoclave having a stirrer, 1 g of partially saponified polyvinyl alcohol and 3000 g of ion-exchanged water were charged and dissolved well. 1500 g in which 0.657 g of 1,1,2-trimethylpropylperoxy neodecanoate was dissolved by sufficiently purging the system with nitrogen.
Of vinyl chloride monomer. The polymerization was carried out at an internal temperature of 57 ° C. while stirring. In 6 hours, the internal pressure exceeds the equilibrium pressure.
It decreased by 5 kg / cm ³ . The vinyl chloride produced at this point was filtered, washed and vacuum dried at 40-50 ° C.
The polymerization rate was 82.0%.

An initial coloring test was performed using the obtained vinyl chloride. At the same time, the odor was checked. Table 1 shows the results
Shown in

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

[Odor test] The odor of the sheet produced in the initial coloring test was examined.

Reference Example 2 The procedure of Reference Example 1 was repeated, except that the vinyl chloride monomer of Reference Example 1 (1200 g) and vinyl acetate (300 g) were used.

Example 1 0.374 g of 1,1,2-trimethylpropylperoxy neodecanoate was used as the polymerization initiator of Reference Example 1,
0.476 g of ethylhexyl peroxydicarbonate
Polymerization was carried out in the same manner as in Reference Example 1 except for changing the composition.

[0026] The polymerization initiator of Example 2 Reference Example 1 1,1,2-methylpropyl peroxyneodecanoate 0.374 g, except for changing the tertiary butyl peroxyneodecanoate 0.336g in Reference Example 1 Polymerization was carried out according to the procedure.

[0027] Except for changing the polymerization initiator in Comparative Example 1 Reference Example 1 to di-2-ethylhexyl peroxydicarbonate 0.830g was subjected to polymerization according to Reference Example 1.

[0028] except for changing the polymerization initiator of Comparative Example 2 Reference Example 1 to cumyl peroxyneodecanoate 1.049g was carried out polymerization according to Reference Example 1.

[0029] Except for changing the polymerization initiator in Comparative Example 3 Reference Example 1 1,1,3,3-tetramethylbutyl peroxyneodecanoate 0.824g was subjected to polymerization according to Reference Example 1.

[0030] except for changing the polymerization initiator in Comparative Example 4 Reference Example 1 di-2-ethylhexyl peroxydicarbonate 0.476 g, a cumyl peroxyneodecanoate 0.420g was subjected to polymerization according to Reference Example 1 .

[0031] The subjected to polymerization according to Reference Example 1 except changing the polymerization initiator in Comparative Example 5 Reference Example 1 di-2-ethylhexyl peroxydicarbonate 0.476 g, a tertiary butyl peroxyneodecanoate 0.411g Was.

COMPARATIVE EXAMPLE 6 0.476 g of di-2-ethylhexyl peroxydicarbonate and 0.37 g of 1,1,3,3-tetramethylbutylperoxy neodecanoate were used as the polymerization initiator of Reference Example 1.
Polymerization was carried out in the same manner as in Reference Example 1 except that the amount was changed to 4 g.

Table 1 shows the above results. From the table, it is necessary to increase the amount of the initiator in order to increase the productivity in the known combination of initiators in order to increase the productivity, and there was also a problem in the results and the odor in the initial coloring test. ,
It can be seen that both are improved when the initiator of the present invention is used alone or in a mixed system with a specific peroxide.

[0034]

The specific peroxyester of the present invention has a low half-life temperature (41.5 ° C), and the polymerization time is shorter if the amount used is the same as compared with the known tertiary alkyl peroxyester. In order to make the polymerization time approximately the same, the amount used is small. Furthermore, the odor during the processing of the polymer and the coloring of the processed product are improved. Further, by using the peroxyester in combination with a specific peroxide having a half-life temperature of 43 ° C. to 65 ° C., the polymerization rate is stabilized and the polymerization time is shortened.

[0035]

[Table 1]

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-57-139104 (JP, A) JP-A-4-198306 (JP, A) JP-A-3-20309 (JP, A) JP-A-1- 110511 (JP, A) JP-A-5-105709 (JP, A) JP-B-47-18852 (JP, B1) JP-B-51-38752 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 4/00-4/82 C08F 14/00-14/28 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (A) General formula (1) (R1, R2, and R3 are each an alkyl group having 1 or more carbon atoms, and the total number of the carbon atoms is 8.) 1,1,2-Trimethylpropylperoxy neodecanoate represented by ) 10 hour half-life temperature is 40 ° C
The dialkyl peroxydicarbonate and peroxye carbonate having a temperature within a range of not more than 10 hours and a half-life temperature (48 ° C.) of tertiary butyl peroxy neodecanoate,
A method for polymerizing a vinyl chloride-based monomer, comprising using a polymerization initiator mixed with at least one selected from the group consisting of stel .