KR800000387B1 - Polymerization of vinyl chloride - Google Patents

Abstract

A preventing method of adhesion of scale in the process of suspension polymn. of vinyl chloride is described. Inner side of polymn. appts. was coated with (a) polaric organic compd. or organic dyestuff (b) water-sol. organic compd. or organic dyestuff, and (c) its surface was treated with aq. metal salts. Thus, Inner side of polymn. appts. was coated with 0.5 wt. % methanol soln. contg. Sudan B(organic dyestuff) and nigrosine (water-sol. dyestuff). vinyl chloride was polymerized using the appts.

Description

Polymerization of Vinyl Chloride

The present invention relates to a method of polymerizing vinyl chloride or vinyl chloride and mixtures of monomers copolymerizable with them, the method of preventing adhesion of polymer scales on the inner wall of the polymerizer and other monomer contacting parts. .

Conventionally, suspension polymerization method, emulsion polymerization method, solution polymerization method, gas phase polymerization method and bulk polymerization method and the like are known as the production method of vinyl chloride resin. There was a problem.

Therefore, in addition to the decrease in the yield of the polymer, the cooling capacity of the polymerizer, etc., the scales are separated and incorporated in the product, which has disadvantages such as degrading the quality of the product. Not only does it require excessive effort and time, but the unreacted monomers are adsorbed on this scale, causing the risk of human injury caused by vinyl chloride monomer, which has become a very serious problem in recent years.

Thus, for the purpose of preventing adhesion to the polymer wall or the like of the polymer scale, for example, the surface of the polymer is coated with a polar organic compound such as an amine compound, a quinone compound and an aldehyde compound, a dye and a pigment to the inner wall and the stirrer. Method is already known (see Japanese Patent Publication Nos. 45-30343, and 45-30835).

It has been found that this method is not effective in the polymerization process in which vinyl chloride is polymerized in the presence of an emulsifier or combined with a comonomer to polymerize, and the polymer mixture is also an acylper such as benzoyl peroxide, lauroyl peroxide and the like. It has been found that it contains higher carboxylic acids such as oxides or lauric acid and stearic acid or salts thereof. Moreover, according to these methods, the effect of anti-scale on the repeated polymerization process could hardly be maintained.

The first object of the present invention is to substantially improve the polymer scale in the polymerizer inner wall or the polymerizer inner wall and other monomer contact portions in all kinds of polymerization reactions when polymerizing a monomer mixture composed of vinyl chloride or vinyl chloride as a main component. It is to provide a polymerization method that can be prevented by.

A second object of the present invention is to provide a polymerization method of a vinyl chloride or a mixture of monomers in which vinyl chloride is a main component, by which the productivity of the vinyl polymer can be greatly increased.

It is a third object of the present invention to provide a method in which a high quality vinyl polymer can be easily produced in a polymerization method of a monomer mixture composed of vinyl chloride or vinyl chloride.

Prior to the start of the polymerization reaction, in the presence of a polymerization initiator, prior to the start of the polymerization reaction, the vinyl chloride monomer or the monomer mixture consisting of vinyl chloride as a main component is polymerized in accordance with the method of the present invention.

(a) at least one organic compound selected from the group consisting of polar organic compounds and organic dyes,

(b) Carboxylates of hydroxides, oxides, halides and metal elements and from the group consisting of oxo acids and salts of these oxo acids of the elements belonging to the second to sixth cycles of the periodic table II B and III-VII Treatment with at least one compound selected.

Examples of the polar organic compound mentioned above as compound (a) are as follows.

(1) nitrogen-containing organic compounds selected from amino, imino, azo, nitro, nitroso or azo methane groups or azine rings with amines, imines and quaternary ammonium salt compounds, for example azomethane, azobenzene, nitrobenzene, nitro Sobenzene, monoaminomononitroazobenzene, pyrazine, pyridine, thiazine, aniline, oxazine (such as morpholine), benzylaniline, EDTA, α- and β-naphthylamine, ethanolamine, diethanolamine, toluidine , Methylene blue, nigrosine black, oil black, spirit black, diaminonaphthalene, diphenyl amine, hydrazine, N, N-dimethylaniline, urea, laurylamine, cetyltrimethyl ammonium chloride, polyamide and polyethyleneamine.

(2) thiocarbonyl, thioether or thioalcohol groups (e.g. thioglycolic acid), thiourea, thiocarbanilic acid, thiocaramic acid, thiobenzoic acid, general formula RSR 'where R and R' Thioethers (e.g., dimethylsulfide and ethyl methylsulfide) and mercaptans (e.g., propylmercaptan and butylmercaptans), polysulfides, polysulfoxides and sulfonic acids (Eg, p-toluenesulfonic acid, cyclohexylsulfonic acid, α-naphthalenesulfonic acid, anthraquinone sulfonic acid, methacrylic acid, dodecylbenzenesulfonic acid) and sulfur-containing organics selected from compounds consisting of salts with alkali metals such as sodium and potassium compound.

(3) oxygen-containing organic compounds selected from the group of quinones, ketones, aldehydes, ethers, alcohols and alkali salts thereof, esters, carboxylic acids and salts thereof, sulfoxides and oximes such as p-benzoquinone, Anthraquinone, benzophenone, acetphenone, diisopropyl ketone, formaldehyde, acetaldehyde, benzoaldehyde, octyl alcohol, cetyl alcohol, benzyl alcohol, phenol, cresol, hematein, propargyl alcohol, hydroquinone, fluoro Lecein, ethylene glycol, pentaerythritol, glucose, sucrose, polyvinyl alcohol, diisopropyl ether, diphenyl ether, cellulose ether, amyl acetate, ethylbenzoate, stearic acid, benzoic acid, salicylic acid, maleic acid, oxalic acid, Tartaric acid, rochel salt, succinic acid, dried acid, isnicotinic acid, phenylglycine, 3-oxy-2-naphthoic acid, gallinic acid, polyacetal and polyacrylic acid.

(4) phosphorus-containing organic compounds selected from phosphoric acid and polyphosphate esters and their alkali metal or ammonium salts, such as monolauryl phosphate, sorbitan hexametaphosphate, polyoxyethylene sorbitan triphosphate and pyriic acid.

(5) Tares, pitches, rosins and waxes with little chemical formula.

Moreover, the organic dye mentioned as compound (a) can be illustrated as follows.

Azo dyes such as monoazo dyes, polyazo salts, metal-containing azo dyes, naphthol dyes (azo dyes and inert dyes) and dispersed azo dyes; Anthraquinone dyes such as anthraquinone salts, anthraquinone bat dyes, anthrone bat dyes, alizarin salts and dispersed anthraquinone dyes; Indigo dyes such as Brilliant Indigo B, Threne Red Violet RH and Threne Printing Black B; Sulfide dyes such as sulfablue FBB and sulfablack B and SudanB; Phthalocyanine dyes such as copper or metal-free phthalocyanine compounds, diphenylmethane, or triphenyl methane dyes, nitro dyes, nitroso dyes, thiazole dyes, xanthene dyes, acridine dyes, azine dyes, oxazine dyes , Thiazine dyes, benzoquinone and naphthoquinone dyes and cyanine dyes and water-soluble organic dyes, such as Direct Brilliant Yellow G (direct dyes), Acid Light Yellow 2G (acid dyes), Levafix Yellow 4G (reactive dyes), Procion Brilliant Orange G (reactive dye), Direct Fast Scarlet GS (direct dye), Direct Bordeaux NS (direct dye), Brilliant Scarlet 3H (acid dye), Acid Alizarin Red B (acid dye), Direct Turkish Blue GL (direct dye) ), Cibacron Blue 3G (reactive dye), Blankophor B (acid dye), Nigrosine (acid dye), Sirius G (direct dye), Chrysamine G (direct dye), Direct Fast Yellow GG (direct dye), Chrome Yellow G ( Acid dyes), Chrome Yellow ME (acid dyes) , Eosine G (acid dye), Basic Flavin 8G (basic dye), Astrazon Yellow 3G (basic dye), Rhodamine 6GCP (basic dye), Safranine T (basic dye), Rhodamine B (basic dye), Daitophor AN (basic dye) ), Auramine Conc (basic dyes), Chrysoidine (basic dyes), and Bismarck Brown BG (basic dyes).

The polar organic compound wave organic dyes may be used alone or in combination.

On the other hand, the compounds mentioned as compounds (b) useful in the process of the present invention are selected from halides, oxides, hydroxides and lower carboxylates of metal elements, the metal elements being alkali metals such as sodium and potassium, magnesium, Alkaline earth metals such as calcium and barium, zinc group metals such as zinc, aluminum group metals such as aluminum, tin group metals such as titanium and tin, iron group metals such as iron and nickel, chromium group metals such as chromium and molybdenum, manganese and Copper group metals, such as manganese metal, copper, and silver, and platinum group metals, such as platinum, can be illustrated. Examples of these compounds are sodium fluoride, sodium acetate, ferrous chloride, calcium chloride, potassium chloride, sodium stannate, sodium chloride, calcium acetate, titanium dioxide, sodium hydroxide, aluminum chloride, cupric chloride, manganese dioxide, ferric octanoate, and tin tin Etc. 、

On the other hand, the compound of (b) is selected from oxo acid and an inorganic salt of the oxo acid of the element belonging to the second to sixth cycles of the periodic table IIB and III-VII group.

Examples of elements are zinc, boron, aluminum, carbon, silicon, tin, titanium, nitrogen, phosphorus, sulfur, chromium, molybdenum, tungsten, chlorine and manganese.

Examples of oxo acids and their salts include zinc acid, boric acid, aluminum acid, carboxylic acid, silicic acid, tartaric acid, titanic acid, phosphoric acid (dehydrated and concentrated phosphoric acid such as metaphosphoric acid, pyrophosphoric acid and tripolyphosphoric acid), nitric acid, sulfuric acid, chromic acid, molybdic acid Tungstic acid, manganese acid, chloric acid and permanganic acid and bischromic acid in a higher oxidation state, nitrous acid, hyponitrous acid, phosphoric acid, hypophosphoric acid in a lower oxidation state and salts of these acids with ammonium, alkali metals or alkaline earth metals.

In order to carry out the process of the present invention, prior to using the compounds of (a) and (b), it is advantageous to dissolve or disperse them in a solvent, which is generally water, alcoholic solvents, ester solvents, ketone solvents, Hydrocarbon solvents and chlorinated hydrocarbon solvents are used.

Next, three preferred specific implementations according to the method of the present invention are shown.

First, compound (a) is dissolved or dispersed in one of the solvents, and the resulting solution or dispersion is applied to the portion where the inner wall of the polymerizer and other monomers come into contact, and then the aqueous of component (b) This coated surface is treated using a liquid. This treatment is performed, for example, by the method of putting the aqueous liquid of (b) component into the polymerizer after application, and heating an inside at 50-100 degreeC preferably 10 minutes or more preferably. After the treatment, the liquid may be removed and a normal polymerization operation may be performed thereafter.However, in the polymerization operation in an aqueous medium such as suspension polymerization and emulsion polymerization, the liquid after the treatment is not taken out, and there are monomers and other components necessary for polymerization (dispersant). , A polymerization initiator, etc.) may be added to carry out the polymerization operation.

Secondly, compound (a) is dissolved or dispersed in a suitable solvent, while compound (b) is dissolved or dispersed in the same or different solvent. It is suitable to add the solution or dispersion of compound (a) dropwise to that of compound (b) and then heat at 50 to 100 ° C. The resultant mixture may be applied to a portion where the inner wall of the polymerizer and other monomers contact each other, washed with water if necessary, and then subjected to a normal polymerization operation.

Third, separate solutions or suspensions of compounds (a) and (b) are prepared in the same or different solvents.

The solution or dispersion of (a) and the solution or dispersion of (b) are used alternately on the surface that will come into contact with the monomer once or more. Thus, the coated surface is heat-treated by passing hot water through the jacket or blower warmer in the reactor. Suitably, the application solution or dispersion is used while passing the hot water through the jacket to maintain the temperature of the inner wall between 50 and 100 ° C. More suitably, the application of the solution or dispersion is completed by blowing hot air into the reactor while simultaneously passing hot water through the jacket at every use or application.

In the above method, it is suitable that the compounds (a) and (b) are brought into contact with each other at a high temperature of 50 ° C or higher. If it is below this temperature, a satisfactory result is not obtained, and the processing requires more than 10 hours.

The ratio of compound (b) to compound (a) used in the process of the present invention may vary depending on the type of compound used and the type of polymerization involved. In particular, in the above-mentioned first method example in which compound (b) has a low concentration in an aqueous solution state and in the third method example in which compounds (a) and (b) do not mix well with each other, compound (b) vs. compound (a) It is suitable that the ratio is relatively large, and in general, a weight ratio of 0.1: 1 to 500: 1 is suitable. In the second method example using the heat treatment mixture of compounds (a) and (b), the ratio of compound (b) to compound (a) may be relatively small, with a weight ratio of 0.01: 1 to 50: 1 being suitable.

The amount of the compound (a) or (b) or the mixture thereof used in the inner wall and other parts of the polymerizer by the present invention may be somewhat the same as in the case of using a conventional coating material by the prior art.

For example, it is possible to sufficiently prevent deposition of the polymer scale in an amount of at least 0.001 g / m ² .

In connection with the three method examples described above, any one of these method examples may be used alone or in combination, as a matter of course. For example, the surface is first applied with a mixed solution of the compounds (a) and (b), and then heat-treated as in the second method example to apply the applied surfaces of the solution of the compound (a) and the compound (b). The coating treatment was continued with a solution, followed by heat treatment as in the third method example.

Moreover, when using two types of compound (a) in mixture, a good result can be obtained by selecting one of these compounds from a water-soluble compound, and the other from an organic soluble compound in some cases.

Further, a better anti-scaling effect can be obtained by adding a solution or dispersion of compound (a) or (b) or a mixed heat treatment solution or dispersion of compounds (a) and (b) to the relevant polymerization mixture. In this case, the addition amount should be limited to the range of several ppm to 100 ppm with respect to the amount of the monomer, since the excess addition amount adversely affects the resulting polymer product.

By the present invention and in order to increase the effect of preventing scale deposition, the polymer mixtures, although not in accordance with the definition of compound (b), are oxides, hydroxides, carbonates of alkaline substances, for example alkali metals, alkaline earth metals and ammonium A method of adding phosphates, bicarbonates, fungi and acetates has been proposed. However, the alkaline material must be added in an amount that does not degrade the resulting polymer. Suitable amounts are, for example, up to 1% by weight relative to the monomer or monomer mixture.

The process of the present invention can be used in all types of polymerization methods, for example suspension polymerization, emulsion polymerization, solution polymerization and bulk polymerization of vinyl chloride monomer or monomer mixtures composed mainly of vinyl chloride. In addition, the method of the present invention is not limited to various additives such as suspending agents, emulsifiers, chain transfer agents, polymerization initiators, polymerization temperatures and stirring speeds.

The method of the present invention can be effectively used not only for homopolymerization of vinyl chloride but also for copolymerization of vinyl chloride and copolymerizable monomers. As the polymerizable monomer, vinyl ester, vinyl ether, acrylic acid and methacrylic acid and esters thereof, maleic acid and fumaric acid and esters thereof, maleic anhydride, aromatic vinyl monomer, vinyl halides other than vinyl chloride, vinylidene halides, olefins, Acrylonitrile and methacrylonitrile are mentioned.

The invention will be explained in more detail by the following examples.

Example 1

The inner wall and the stirrer of a 1000 L stainless steel polymerizer having a paddle-type stirrer containing 0.5 wt% methanol solution of Sudan B (organic dye) and nigrosine (aqueous dye) at a ratio shown in Table 1; It is applied to the surface of the stirrer shaft (4m ² ) to 0.05g / m ² (solid content). Next, 500 kg of water in which the metal salt was dissolved was added to the polymerization reactor as in Table 1, and the mixture was heated for 30 minutes under stirring at 110 rpm. Thereafter, the contents were cooled, and 3 kg of sodium lauryl sulfonate, 3 kg of cetyl alcohol, 200 g of dimethylvaleronitrile and 200 kg of vinyl chloride were charged, and suspension polymerization was carried out according to a conventional method at 50 ° C for 7 hours. After the reaction type, the coated surface was washed with water and dried, and then the scale adhesion was measured as described in Table 1.

When the means or Nigrsine were used alone for comparison purposes, the case where no metal salt was used was described together.

TABLE 1

Note: * Control

** No heat treatment

Example 2

In a similar manner, the same polymerizer as used in Example 1, either alone or mixed with a polar organic compound or organic dye as shown in Table 2, and 1% dissolved or dispersed in a metal salt as shown in Table 1 at 90 ° C. for 30 minutes. It applied by heat-processing previously. After washing the coated surface with water, 100 kg of vinyl chloride, 200 kg of water, 0.05 kg of diisopropylperoxadicarbonate, 1 kg of sodium dodecyl benzenesulfonate and 1.5 kg of cetyl alcohol were charged to each polymerizer, followed by 8 hours. The emulsion polymerization was carried out at a high temperature, i.e., 45 DEG C, under a stirring speed of 110 rpm. After completion | finish of reaction, the scale adhesion amount was tested and measured. The results are shown in Table 2.

TABLE 2

Note: * Control

Toluene and Methanol

*** ethanol and methylene chloride

Example 3

The same polymerizer as used in Example 1 was applied in the same amount as used in Test No. 32 of Example 2 in an amount of 0.1 g / m ² (solid). Each coated polymerizer was charged with 100 kg of vinyl chloride, 200 kg of water and a variable amount of polymerization initiator, suspending agent and / or other additives or comonomers as shown in Table 3, followed by stirring at 100 rpm for 10 hours. Suspension polymerization was performed at high temperature, that is, 57 ° C. After completion of the reaction, the scale adhesion amount was examined. The results are shown in Table 3.

For control, similar polymerization was carried out in the polymerization reactor using the same additives or comonomers as described above, which had been previously applied with a single dye, ie, nigrosine base, or not at all.

The scale adhesion amount produced is shown in Table 3.

In Table 3, PVA is polyvinylacetate, HPMC is hydroxypropyl methylcellulose, IPP is diisopropylperoxydicarbonate, LPO is lauroyl peroxide, and BPO is benzoyl peroxide.

TABLE 3

Note: * Control, no coating

Example 4

The same coating material as used in Test No. 33 of Example 2 was applied to the inner wall surface of the bulk polymerization and the parts of the combined container, the first vessel being a vertical type, 2 liter stainless steel forcing, and the second vessel It is a horizontal type forced stainless steel for 4L. Then, all the coated surfaces were washed with water. The first vessel was filled with 800 g of vinyl chloride and 0.4 g of dimethylvaleronitrile, and then subjected to bulk polymerization at 60 ° C. under a stirring speed of 900 rpm for 2 hours. The reaction mixture was transferred to a second vessel filled with 800 g of vinyl chloride and 0.4 g of dimethylvaleronitrile and then polymerized at 57 ° C. under a stirring speed of 100 rpm for 10 hours. After the completion of the polymerization, the polymer scale deposition amount was inspected for each polymerizer.

For comparison, a similar test was conducted without applying the coating or by applying only nigrosine base.

The test results are shown in Table 4.

TABLE 4

Note: * Contrast

Example 5

Suspension polymerization was carried out for 10 hours using the same method and additives as in Example 3 with the same polymerizer used in Test No. 31 of Example 2 and applied, except for the case of some tests, Test No. 31 Was applied to the polymerization mixture in varying amounts as shown in Table 5, and for other tests, an alkaline substance, ie sodium hydroxide, calcium hydroxide or sodium acetate, was added as described in Table 5. This polymerization test was repeated, and the deposition amount of the scale was observed visually or by the same method as in Example 1. The results are shown in Table 5.

Note: Amounts in ppm or% are for weight of vinyl chloride monomer.

* The number of hours is the number of hours that have elapsed since the start of the start test of each polymerization test.

Claims (1)

When polymerizing a vinyl chloride or vinyl chloride-based monomer mixture, the polymer inner wall or the inner wall of the polymerizer and other monomers contact with each other in advance. (a) a polar organic compound and / or an organic dye (b) after applying the water-soluble organic compound and / or the water-soluble organic dye, and then applying the coated surface thereof (c) treating with an aqueous solution of a metal salt or A method of polymerizing vinyl chloride, characterized by applying a liquid prepared by treating the component (a) and the component (b) with the component (c).