JPS58134103A - Suspension polymerization of vinyl chloride or similar unsaturated monomer - Google Patents

Abstract

PURPOSE:A nonionic emulsifier containing no polyoxyethylene groups is added to a system consisting of an organic peroxide with a specific freezing point and a specific temperature of 10-hour half life, a water-soluble alcohol and water and polymerization is effected to give the titled polymer with high electric insulation. CONSTITUTION:An aqueous emulsion of monomers is prepared by adding an emulsifier with a HLB of 4-10 or an emulsifier mixture with the same HLB, which contains no polyoxyethylene groups, such as lauric acid saccharose ester to a system consisting of an organic peroxide with a melting point lower than 0 deg.C and lower than 75 deg.C at which its half life shows 10hr such as di(2-ethylhexyl) peroxy carbonate, a water-soluble alcohol of lower than 100mol.wt. such as methanol and water and the resultant emulsion is subjected to polymerization to give the objective polymer.

Description

[Detailed description of the invention] The present invention is a method for suspension polymerization of vinyl chloride-based unsaturated monomers.

More specifically, by using an aqueous emulsion of organic peroxide containing a specific emulsifier and having excellent stability over time and safety as a polymerization initiator, a vinyl chloride unsaturated monomer can be used to produce a polymer with excellent electrical insulation properties. The present invention relates to a suspension polymerization method.

Polyvinyl chloride polymers are widely used as insulating materials for electric wires and other electrical parts.

In order to be used as an electrically insulating material, it is extremely important to increase the electrical insulation properties and volume resistivity as much as possible. More recently, Bo IJ
In order to improve productivity in producing vinyl chloride polymers and to prevent environmental pollution due to the toxicity of residual and discarded vinyl chloride unsaturated monopolymers, we have enlarged the polymerization equipment and changed the production system. In addition to automatic continuous system, the entire polymerization reaction system is closed system.

Suspension polymerization of vinyl chloride-based unsaturated monocrystalline polymers is usually carried out by using protective colloids and/or emulsifiers to obtain polymers of desired particle size, and by using a polymerization initiator m+ to initiate the polymerization reaction. It is done. However, when these additives are used, it is known that the properties of the polymer product, such as volume resistivity, are adversely affected depending on the type of additive.

Currently, radical polymerization initiators active at low temperatures are mainly used as polymerization initiators for vinyl chloride-based unsaturated monomers in order to improve productivity through cycle-up. Such polymerization initiators are mainly organic peroxides such as peroxyredicarbonates, peroxyesters, diacyl peroxides, which are generally very reactive, unstable and highly dangerous substances. . These polymerization initiators are undesirable from the viewpoints of handling, safety, and toxicity.

Therefore, in recent years, water emulsions or suspensions of organic peroxides that can be used even in closed systems have been proposed.

For example, a solid organic oxide is used in the polymerization initiator suspension, and) a nonionic emulsifier that has an ILB value greater than 15 and contains a polyoxyethylene group and does not contain a cyclic internal ether bond is used. method (JP-A No. 56-110703), a nonionic emulsifier having an HL'B'bf value of greater than 15 and a polyoxyethylene group, and a nonionic emulsifier having an HLB (* of less than 9 and a polyoxyethylene group); An emulsifying system consisting of a nonionic emulsifier that does not have groups, and the HLB value of the mixed emulsifier is 11 to 17.
A method using a method that falls within the range of . (Unexamined Japanese Patent Publication No. 56-110
702) Organic peroxides, emulsifiers that still contain alkanols with 1-4 carbon atoms and/or alkanediols with 2 to 4 carbon atoms and are liquid at -5°C and/or a method using a water emulsion consisting of a protective colloid (JP-A-56-1895)
No. 09) is disclosed.

However, these methods have several drawbacks as described below.For example, the method using an aqueous suspension obtained from a solid organic peroxide mentioned at the beginning
If it adheres or remains inside the container or piping, the danger increases because highly pure organic peroxide is likely to precipitate due to water evaporation.
It is very difficult to remove nitrates, and the removal operation is quite dangerous, so it is not suitable for automatic feeding by pumping. The method of obtaining a liquid emulsion of organic peroxide in water using the emulsifier used in the water suspension of the oxide has the disadvantage that a sufficiently stable emulsion cannot be obtained. When the method using a water emulsion of an organic peroxide was repeated, the electrical properties of the cured polymer were significantly impaired, and it could not be used as an electrically insulating material.

The present inventors conducted research in search of a method for solving the above-mentioned drawbacks and providing a polymer with excellent safety and stability as well as excellent electrical properties. and an emulsifier with an HLB value of Φ~10, or when two or more emulsifiers are combined, the H of the resulting mixed emulsifier
A water emulsion of a specific organic peroxide obtained using a mixed emulsifier with an LB value of 4 to 10 has excellent stability, and this water emulsion can be used to suspension polymerize vinyl chloride-based unsaturated monomers. This led to the completion of the present invention based on the knowledge that the vinyl chloride polymer obtained by the above method has excellent electrical properties.

That is, in the method of the present invention, the freezing point is below 0°C and 10°C.
A system consisting of an organic peroxide whose warm half-life is 75°C or less, a water-soluble alcohol with a molecular weight of 100 or less as an anti-caking agent, and water containing a polyoxyethylene group. HLB for a single emulsifier, or for a mixed emulsifier in the case of two or more emulsifiers
Characterized by suspension polymerization of vinyl chloride-based unsaturated monomer m1 using an aqueous emulsion of an organic oxide obtained by adding at least one non-iodic emulsifier having a value of 4 to 10 as a polymerization initiation -j. That is.

The method of the present invention relates to the polymerization of an unsaturated monomer of vinyl chloride, and can be applied not only to homopolymerization of vinyl chloride but also to copolymerization mainly composed of vinyl chloride. In this case, the comonomers copolymerized with vinyl chloride include vinyl esters, vinyl ethers, esters of methacrylic acid, α-olefins, aromatic vinyls, vinyl halides other than vinyl chloride, vinylidene halides, and maleic acid. Examples include acids or hafmaric acid esters, which are generally used in an amount of 30% by weight or less when mixed with vinyl chloride. Preparation of water emulsion of organic peroxide used in suspension polymerization of the present invention is carried out by adding an aqueous solution obtained by dissolving an emulsifier and a water-soluble alcohol with a molecular weight of 100 or less in water to an organic peroxide while stirring, or by adding/adding an organic peroxide to the aqueous solution. I can do it. At this time, the emulsifier can also be used after being dissolved in an organic peroxide.

The water emulsion of organic peroxide thus obtained has water as a continuous phase, and therefore exhibits excellent properties in terms of safety and stability.

Further, such a water emulsion of a severely degraded organic product has excellent storage and transportability in low-grade products due to the anti-caking effect of the water-soluble alcohol.

The organic peroxide used in the present invention is one or more organic peroxides that exhibit a half-life of 10 hours at a temperature of 75°C or lower and have a freezing point of 0°C or lower. Further, the present invention also includes a mixed organic peroxide having a freezing point of 0°C or lower, which is a mixture of the organic peroxide and an organic peroxide having a freezing point of 0°C or higher. The term "preparation" having a half-life of 10 hours refers to solvents that are relatively inert to organic peroxides, such as pen. When zene or toluene is mainly used to make the peroxide concentration from about αl to 0.2 mol/l and kept at a certain wettability, the original organic peroxide decomposes and its active oxygen It means the flow rate such that the time required for the amount to reach % is 10 hours.

Specific examples of the organic peroxide include di(n-propyl)peroxydicarbonate, di(isopropyl)peroxydicarbonate, di(Sec-butyl)
Peroxydicarbonates such as peroxydicarbonate, di(caprylic)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, di(2-ethoxyethyl)peroxydicarbonate, di(methoxyisopropyl)peroxydicarbonate, t
-Butylperoxyneodecanoate, cumylperoxyneodecanoate, t-phthylberoxypivalate, t
-Butylperoxyin butyrate, t-butylperoxy-8,5,5-trimethylhexanoate, t-7
There are peroxy esters such as 'tylperoxy-2-ethylhexanoate, diacyl peroxides such as diacetyl peroxide, cyclobionyl peroxide, diimbutyryl peroxide, di(8,8,5-trimethylhexanoyl) peroxide, and mixed organic Examples of the peroxide include a mixture of di(2-ethylhexyl) peroxydicarbonate and acetylcyclohexylsulfonyl peroxide. In the present invention, a solvent may be added in order to make the organic peroxide more stable or to lower its freezing point.

The content of the organic peroxide in the organic peroxide water emulsion used in the present invention is usually 5 to 80% by weight.
If □・ is too small, the transportation cost will be high and it is economically undesirable; if it is too large, it will be difficult to obtain a product with excellent safety, so it is preferably 10 to 65% by weight. be.

The remainder is water, an emulsifier, and a water-soluble alcohol with a molecular weight of 100 or less.

The water-soluble alcohol with a molecular weight of 100 or less used in the present invention refers to a low-molecular-weight alcohol that dissolves in water in any proportion, such as methyl alcohol, chloroalcohol, n-flobil alcohol, and inpropyl alcohol. ) ethylene glycol) glycerin, phosphorus, etc.

Low-molecular-weight water-soluble alcohols have traditionally been considered undesirable solvents because they significantly reduce the storage stability of organic peroxides. The water emulsion of organic peroxide does not impair the stability of the organic peroxide.

If the amount of water-soluble alcohol used is too small, the degree of freezing point depression will be small, and if it is too large, the organic harsh substance will become unstable. It is desirable that the Two or more of the water-soluble alcohols may be used in combination.

The nonionic emulsifier used in the water emulsion of the harsh organic material used in the suspension polymerization of the present invention must not contain a polyoxyethylene group as a hydrophilic group in its molecule. In particular, sorbitan monoesters, sorbitan diesters and sorbitan triesters of lauric, palmitic, stearic or oleic acids and sucrose monoesters of lauric, palmitic, stearic or oleic acids,
Examples include saccharose diester and sucrose triester. Commercial products of the above-mentioned sorbitan mono-, di- and triester include, for example, the product names: /-:tyLP-2QR, tyLP-40'It (produced by Nippon Oil & Fats Co., Ltd.).
TifJ OP-80R% TifJ OP-80R% TifJ OP-83RAT, TifJ OP-85R, etc. In addition, the above-mentioned sucrose mono-, di- and triesters include:
For example, Ryoto Sugar Ester S- manufactured by Ryoto Co., Ltd.
879, S-770, S-1170, S-187
0s Same P-1670゜ Same LWA-15401 Same OWA
1570 etc.

Two or more emulsifiers can be used in combination so that the resulting mixed emulsifier has an HLB value of 4 to IO.0 If the HLB value is less than 4 or more than 10, water of a harsh organic compound with good storage stability may be used. It becomes difficult to obtain an emulsion.

Considering the economic efficiency and the influence on the quality of the obtained polymer, it is preferable to use the minimum amount of the nonionic emulsifier necessary to obtain a stable water emulsion.
Usually the amount used is 0.001 to 0 per 1 part by weight of water.
．． within the range of 15 parts by weight, preferably from 0.005 to O,
It is within the range of 1 part by weight.

The HLB value is a hydrophilic value as described in the "Surfactant Handbook" Kogaku Tosho Co., Ltd. edition (197?) co-edited by Takahashi, Namba, Koike, and Kobayashi of Nippon Oil & Fats Co., Ltd.
This should be understood as a lipophilic balance. As stated in the above publication, the HLB value mentioned above can be determined using a simple calculation formula for various non-ine emulsifiers, and when two or more emulsifiers are used in combination. It can be calculated from the weight ratio of each component.

The water emulsion used in the present invention has a relatively low viscosity, so that it is easy to handle and can be pumped. , generally less than 20 voids are preferred, and the water emulsions are very stable and do not exhibit any phase separation of the kind that cannot be used in polymerizations after relatively long storage periods.

In order to prevent that the organic peroxide in the water emulsion can no longer be homogeneously distributed in the continuous phase in the event of phase separation, it may act as a thickener and/or a protective colloid in the water emulsion. It is appropriate to incorporate substances that These substances are preferably used in such a way as to prevent phase separation to the maximum possible extent.

Examples of suitable substances for this purpose are synthetic and natural polymers, which may be partially hydrolyzed, such as polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, and combinations with acrylic amides or acrylic esters. Acrylic acid copolymers, water-soluble cellulose derivatives such as hydroxyethyl and hydroxyglobil cellulose, methylcellulose and carboxymethylcellulose, gelatin, starch, and the like. Protective colloid device
It is suitably selected depending on the desired viscosity of the water emulsion, emulsifier and organic peroxide.

The amount used is within the range of 0.5 parts by weight, preferably 0.005 to 0, per 1 part by weight of water.
It is within the range of 1 part by weight. Among these, polyvinyl alcohol or aqueous cellulose derivatives are preferably used.

A well-known apparatus can be used to produce the aqueous emulsion of 11:il of organic harsh material used in the suspension polymerization of the present invention. For example, a paddle-type, propeller-type, or turbine-type mechanical rotating stirrer can be used, and a colloid mill, homogenizer, high-speed shear emulsifier, ultrasonic homogenizer, etc. can also be used. of m a m
Except for using a water emulsion of the compound, the process can be carried out according to the conventional method of polymerizing vinyl chloride in an aqueous medium.
Therefore, for example, any conventionally known suspending agent may be used in an appropriate amount, and there are no particular limitations.

Since the method of the present invention is configured as described above, it has several advantages as shown below. First, because eight polyvinyl chloride polymers with excellent electrical properties can be obtained, products obtained from the same batch can be used for a variety of purposes, and the large-scale production of large-scale polymerization equipment has led to a wide variety of products. Production becomes possible.

Second, since the water emulsion can be stored cooled to below 0° C. without condensation, deterioration of the organic peroxide can be prevented, and it is possible to automatically feed the organic peroxide in its original form to polymerization equipment.

Thirdly, the water emulsion has excellent safety because the organic peroxide and water are emulsified in a preferable state. For example, there is no severe self-accelerating decomposition or violent combustion upon ignition, which is the case with conventional radical polymerization initiators, making storage, handling, and transportation extremely safe. Therefore, damage caused by backflow of vinyl chloride that sometimes occurs when a polymerization initiator is charged after vinyl chloride is charged into the polymerization equipment can be minimized.

Fourth, it is a low viscosity liquid and can be easily diluted with water, making it suitable for equipment, pumping and/or pressurized transportation in required quantities. Furthermore, if it adheres or remains inside the container or piping, it can be easily washed away with water.

Next, Examples, Reference Examples, Comparative Examples, and Comparative Polymerization Examples will be explained, but they are merely illustrative and the present invention is not limited to them.

Comparative Example] Reference Example 1 Di(2-ethylhexyl), which has a freezing point of -5o (() and a temperature of 43.5°C (which exhibits a half-life of 10 hours below Add 40 liters of peroxydicarbonate and set the bath temperature to 2.
The temperature was raised to 0°C. There were added 43 parts by weight of water, 12 parts by weight of methyl alcohol, 2 parts by weight of polyvinyl alcohol, and 15 parts by weight of sorbitan monolaurate (trade name Ninonion LP-2OR, HLB 8.6, NOF Corporation).
W ) and 1.5 parts by weight of sorbitan monooleate (trade name: /=: ton 0P-8OR, HLB43;
A mixed solution of a mixed milk agent (manufactured by NOF Corporation) having an HLB value of 65 was added dropwise with stirring. After dripping, 20
When stirring was continued for several minutes, the viscosity was 21°C/1.
A homogeneous and stable milky-white organic peroxide water emulsion with 8 voids was obtained. When this sample was placed in a container maintained at -15°C and a storage stability test was conducted for one month, it was found that the sample was stable, with no decrease in peroxide content or change in shape. . Furthermore, the water emulsion of the obtained organic peroxide was tested according to the safety test described below, and the results are shown in Table 1. Comparative Example 1 Instead of using sorbitan monolaurate and sorbitan monooleate as emulsifiers, HLB The value is 18.
An aqueous emulsion of organic peroxide was produced according to Reference Example 1, except that 8 parts by weight of polyoxyethylene monostearate (trade name: Nonion 5-40, manufactured by NOF Corporation) of No. 2 was used. The viscosity is 1.2 poise at 21°C. A homogeneous milky white organic peroxide water emulsion is
Hiro. However, when a storage stability test at -15°C was carried out, the product was separated by being left for day and night. As mentioned above, it has been found that when emulsifiers other than those defined by the present invention are used, a sufficiently stable water emulsion of organic peroxide cannot be obtained.

Comparative Example 2 Using sorbitan monolaurate and sorbitan monooleate as emulsifiers, 11 (LBi direct 18)
．． 2 polyoxyethylene monostearate (trade name;
2.6 parts by weight of Nonion 5-40 (manufactured by NOF Corporation) and sorbitan monostearate with an HLB value of 4.7 (trade name: Nonion 5P-6OR, manufactured by NOF Corporation)
A water emulsion of an organic peroxide was produced in accordance with Reference Example 1, except that a mixed solution having an HLB value of 16 was used as a mixed emulsifier consisting of 0.4 area parts.

As a result, a homogeneous milky white organic peroxide water emulsion with a viscosity of 1.3 poise at 21°C was obtained, but -15
When a storage stability test was conducted at ℃, the product was separated by being left for day and night. As described above, when a mixed emulsifier other than those limited by the present invention was used, a sufficiently stable water emulsion of organic peroxide could not be obtained.

Comparative Example 3 Instead of using sorbitan monolaurate and sorbitan monooleate as emulsifiers, sorbitan trioleate (trade name: Nonion 0F-8) having an HLB value of 1.8 was used as an emulsifier.
A water emulsion of organic peroxide was produced according to Reference Example 1 except that 8 parts by weight of 51, produced by Nippon Oil & Fats Co., Ltd. (Match) was used. A water emulsion of an organic peroxide was obtained. However, when a storage stability test at -15°C was carried out, the emulsion was separated by being left for day and night.

Thus, it was found that when emulsifying with an emulsifier having an I(LB value of less than 4), a stable organic peroxide water emulsion could not be obtained.

Reference Examples 2 to 3 Di(2-ethylhexyl) peroxydicarbonate was used in the same manner as in Reference Example 1, except that in Reference Example 2, 15 parts by weight were used, and in Reference Example 3, 90 parts by weight was used. When water emulsions of organic peroxide containing 60% and 60% by weight were produced, uniform milky white organic peroxide water emulsions were obtained in each example, and the viscosity at 20°C was as follows. What was obtained in Example 2 is 1. Opoise and reference example 3
Then, using the water emulsions of each organic peroxide obtained in Reference Examples 1 to 3, which had a void of 5.9,
The following safety tests were conducted. The results are shown in Table 1. [Safety Test] The organic peroxide water emulsions of Examples 1 to 8 were subjected to a combustion test and a rapid heating test in the following manner. The results are shown in Table 1.

Combustion Test A combustion test was conducted using the creepland open flash point pI#i shown in JIS-2274-62 to determine the ignition and extinction temperatures and to observe the combustion state.

The safety evaluation by combustion test is as follows: 0 0 mark: ignition and ignition temperature is 70°C or higher, combustion condition is stable.

△ mark: The ignition and ignition temperature is 66 to 70°C, and the combustion state is somewhat intense.

Rapid heating test A thermostability test is conducted in accordance with the rapid heating test method of O.B.P.N.D. (abbreviation for Organic Peroxide Producer Safety Division), and the temperature at which it begins to rise rapidly and the maximum humidity are determined. The stability evaluation by the zero rapid heating test was separated by the following symbols.

○ mark: Maximum reach wetness is 100°C or less △ mark: Maximum reach wetness is 100 to 180°C Table 1 From Table 1, the water emulsion of organic peroxide used in the method of the present invention has good flammability and thermal stability. It turned out to be very good. It was also observed that these safety levels decreased as the organic peroxide content increased.

Reference Example 4 A water emulsion of organic peroxide was produced according to Reference Example 1 except that the methyl alcohol in Reference Example 1 was replaced with ethylene glycol, and a homogeneous emulsion with a viscosity Tll of 1.2 voids at 20°C was obtained. A milky-white water emulsion of organic peroxide monide was obtained.

Reference Example 5 0.4 parts by weight of saccharose monostearate (trade name: Ryoto Sugar Ester S-1670, HLB14, Yumesei Co., Ltd.) was substituted for the sorbitan monolaurate and sorbitan monooleate of Reference Example 1. ) and 2
．． The procedure of Reference Example 1 was repeated except that a mixed solution of a mixed emulsifier consisting of 6 parts by weight of sorbitan monooleate (trade name: Nonion 0P-8OR, HLB41, manufactured by NOF Corporation) with an HLB value of 5.6 was used. When a water emulsion of organic peroxide was prepared in a similar manner, a uniform milky-white organic peroxide water emulsion with a viscosity of 1.4 voids at 20°C was obtained.

Reference Example 6 Instead of di(2-ethylhexyl)peroxydicarbonate in Reference Example 1, Lr, 4 hard to 10 at 30°C or less
Using t-butyl peroxyneodecanoate with a half-life of 48°C, using 6 parts by weight of methyl alcohol and 6 parts by weight of styrene glycol instead of methyl alcohol, and as an emulsifier. In place of sorbitan monolaurate and sorbitan monooleate, 8 parts by weight of sorbitan monopalmitate (trade name;
A water emulsion of a harsh organic compound was produced according to Reference Example 1 except that nonionic PP-40RXI (LB6.7, manufactured by NOF Corporation) was used, and the viscosity was 1 at 20°C.
．． A homogeneous milky white organic peroxide water emulsion with 8 voids was obtained.

Next, using the water emulsions of organic peroxides obtained in Reference Examples 4 to 6, the same storage stability test and safety test as in Reference Example 1 were conducted. The results of the storage stability and safety tests were almost the same as in Reference Example 1.

Examples 1 to 6, Comparative Examples 4 to 5, and Comparative Polymerization Examples 1 to 2 0.45 parts by weight of polyvinyl alcohol, 11 parts by weight, 300 parts by weight of water, 100 parts by weight of vinyl chloride, and the above-mentioned Reference Example 1 in the amounts shown in Table 2. The water emulsion of organic peroxide obtained in steps 6 to 6 was placed in an autoclave and heated to 58% while stirring.
The reaction was continued for 8 hours until the polymerization reaction was completed. Then, the obtained polymer was dried daily to obtain white powdery polyvinyl chloride at the yield shown in Table 2.

Each obtained polyvinyl chloride 100? And dioctyl phthalate 50? and trisalt striped lead sulfate 81, the resulting mixture was kneaded with a roller for 10 minutes, and then 16
It was pressed into a plate at 0°C. Next, the volume-specific paper resistance of each was measured based on JIS-6911 "General Test Methods for Thermosetting Plastics", and the results are shown in Table 2.

For comparison, 99% pure di(2) was used as a polymerization initiator.
-Ethylhexyl) peroxydicarbonate (Comparative Example 4) or 8 parts by weight of polyoxyethylene nonylphenol ether with an HLB of 95 as one of the conventional emulsifiers. Polyvinyl chloride was prepared according to Examples 1 to 7 using 0.075 parts by weight of the water emulsion of organic peroxide (Comparative Example 5) obtained in the same manner. Turbidity polymerization was carried out, and the convergence and volume resistivity values were determined, and the results are shown in Table 2 as Comparative Polymerization Examples 1 and 2, respectively.

Table 2 ×゛It corresponds to 0608 Kobe as a dry initiator castle.

As is clear from Examples 1 to 5 and Comparative Polymerization Example 1 in Table 2, additives such as emulsifiers and anti-caking agents used in the method of the present invention have a specific effect on the yield and volume of avian polyvinyl chloride. It was found that it had no effect on resistance. Moreover, as is clear from Examples 1 to 6 and Comparative Polymerization Example 2, it can be seen that the method of the present invention provides polyvinyl chloride with superior electrical properties as compared to the conventional method.

Example 7 A vinyl chloride unsaturated monomer was prepared according to Example 1, except that 90 parts by weight of vinyl chloride and 10 parts by weight of vinylidene chloride were used instead of vinyl chloride. Suspension polymerization of polymers was carried out. As a result, 81
A vinyl chloride-vinylidene chloride copolymer was obtained with a yield of 50% and a volume resistivity of 92.times.10" ohm.m.

Comparative Polymerization Example 8 1. As a vinyl chloride unsaturated monomer. Suspension polymerization of a vinyl chloride-based unsaturated monomer was carried out in accordance with Comparative Polymerization Example 3, except that 90 parts by weight of vinyl chloride and 10 parts by weight of vinylidene chloride were used instead of vinyl chloride. the result,
A vinyl chloride-vinylidene chloride copolymer was obtained with a yield of 80%, and its volume resistivity was 19×10” ohm·m.

As is clear from the comparison between Example 7 and Comparative Polymerization Example 8, the method of the present invention provides a vinyl chloride-vinylidene chloride copolymer with superior electrical properties compared to the conventional method. I understand.

Patent applicant: NOF Corporation Representative Patent Attorney Tsukasa Ibino

Claims (1)

[Claims]
The system consisting of a harsh organic compound with a temperature of 75°C or less, a water-soluble alcohol with a molecular weight of 100 or less, and water does not contain polyoxyethylene groups, and in the case of a single emulsifier, the emulsifier itself, or two or more emulsifiers. In the case of a vinyl chloride-based polymer, an organic peroxide water emulsion obtained by adding at least lli or more nonionic emulsifier having an HLB value of 4 to 10 for the mixed emulsifier is used as a polymerization initiator. A method for suspension polymerization of unsaturated monomers. (2) Nonionic emulsifiers containing no polyoxyethylene groups include sorbitan monoesters, sorbitan diesters, and sorbitan triesters of lauric acid, palmitic acid, stearic acid, or oleic acid; The unsaturated vinyl chloride monomer according to claim 1, which is one or more than 21 selected from the group consisting of saccharose monoester, saccharose diester, and saccharose triester of stearic acid or oleic acid. suspension polymerization method. f3) Water m +% Flucol is one or more selected from the group consisting of methyl alcohol, ethyl alcohol, n-7' alcohol, isopropyl alcohol, ethylene glycol, and glycerin, and is chlorinated [ The method for suspension polymerization of vinyl chloride-based unsaturated monomers according to claim 2, wherein the vinyl-based unsaturated monomers are vinyl chloride. (4) 10 to 65% by weight of organic harsh substances, the remainder being water;
It consists of a nonionic emulsifier that does not contain polyoxyethylene groups and a water-soluble alcohol, of which the emulsifier is 0.005 to 1 part by weight per 1 part of water, and the water-soluble alcohol is 0.005 to 1 part by weight per 1 part of water. A method for suspension polymerizing unsaturated monomers in vinyl chloride according to claims 1 to 3, wherein the amount is 0.02 to 7 parts by weight.