JP2007262352A - Method for producing vinyl chloride-based copolymer resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for production by which the time to recover the residual vinyl chloride monomer of a vinyl chloride-based copolymer resin prepared by copolymerizing a vinyl chloride-based monomer with a macromonomer is shortened and the outflow of a slurry to the outside of a polymerizer is reduced. <P>SOLUTION: The method for producing the vinyl chloride-based copolymer resin is carried out as follows. An aqueous dispersion in which the ratio of the vinyl chloride-based monomer to the total amount of constituent monomer components is ≥50 to <100 wt.% is prepared so that the total weight (M) of the macromonomer and the vinyl chloride-based monomer and the initial amount (H) of water are within the range of formula (1) 0<H/M≤3.0 (1) and the amount of an added dispersing agent in the initial water is >0 to ≤0.1 pt.wt. based on 100 pts.wt. of the total amount of the charged monomers. A water-soluble polymerization inhibitor in an amount to be ≥0.0001 to ≤0.001 pt.wt. is then charged. The macromonomer is subsequently dispersed in the initial water and the vinyl chloride-based monomer is charged. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

    The present invention relates to a method for producing a vinyl chloride copolymer resin, and more specifically, a macromonomer having a vinyl chloride monomer and a polymer comprising an ethylenically unsaturated monomer containing a double bond in the main chain. By adding a water-soluble inhibitor at the time of mixing and dissolving, there are few fine particles in the aqueous suspension, and when the vinyl chloride monomer is recovered after the polymerization is completed, the rise in the liquid level can be suppressed and the residual monomer recovery time can be shortened. The present invention relates to a method for producing a vinyl chloride copolymer resin.

  Advances in the synthesis technology of so-called macromonomers, which are oligomers and polymers having a polymerizable functional group at one end, have attracted interest in the development and application of comb-like copolymer resins using these. When such a copolymer resin is produced, solution polymerization is generally performed in which both are dissolved in a suitable solvent together with a polymerization initiator.

  However, since the solution polymerization method easily causes chain transfer to a solvent, it is difficult to produce a polymer comb-like copolymer resin, and the physical properties of the obtained copolymer resin are difficult to adopt for molding materials. There is a problem, and the present inventors have repeatedly studied an aqueous suspension polymerization method (Patent Document 1).

  Usually, in order to reduce the fine particles generated during the polymerization by suspension polymerization, the vinyl chloride resin changes the number of stirring at the initial stage of polymerization or uses PVA having a high degree of saponification as a dispersant. A method of adding a water-soluble inhibitor during polymerization and polymerization is known (Patent Document 2). Although the mechanism of the generation of fine particles and the effect of adding a water-soluble polymerization inhibitor is not clear, when such fine particles float at the liquid interface during self-pressure recovery, bubbles called dry foam are formed and the slurry is scattered. It is known to cause an increase in the liquid level. In order to prevent them, a method of suppressing the formation of fine particles by adding a small amount of a water-soluble inhibitor during polymerization is mentioned.

On the other hand, when the present inventors produce the vinyl chloride copolymer resin of the present invention, in order to prevent the rise of the liquid level during the self-pressure recovery, the prevention of fine particles and dry foam generated during the polymerization. We have been studying earnestly. However, in the case of the vinyl chloride copolymer resin of the present invention, unlike the conventional vinyl chloride resin, the interfacial tension of the aqueous phase is remarkably reduced due to the scattering of the slurry and the rise of the liquid level during the self-pressure recovery. The main factor is that the macromonomer fine dispersion added to the initial water is inhibited from polymerization in the aqueous phase, thereby suppressing the decrease in surface tension in the aqueous phase. Was completed.
JP 2005-179599 A Japanese Patent Laid-Open No. 08-217806

  The present invention recovers a residual vinyl chloride monomer of a vinyl chloride copolymer resin obtained by copolymerizing a vinyl chloride monomer and a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain. It is an object of the present invention to provide a production method that shortens the time and reduces the outflow of slurry to the outside of the polymerization machine.

  As a result of diligent research, the inventors of the present invention introduced a water phase polymerization inhibitor into water in advance, whereby a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain and chlorination. The present inventors have found that the above-mentioned problems can be solved by mixing and dissolving vinyl monomers and then starting a copolymerization reaction, thereby completing the present invention.

That is, the present invention
(1) Manufacture vinyl chloride copolymer resin by suspension polymerization by copolymerizing vinyl chloride monomer and macromonomer having polymer consisting of ethylenically unsaturated monomer containing double bond in the main chain. When doing
After adjusting the amount of the dispersant in the initial water to be more than 0 parts by weight and 0.1 parts by weight or less with respect to 100 parts by weight of the total amount of monomer components (hereinafter referred to as “total amount of charged monomers”), After the water-soluble polymerization inhibitor is added in an amount of 0.0001 part or more and 0.001 part or less with respect to 100 parts by weight of the total amount of charged monomers, a polymer composed of an ethylenically unsaturated monomer containing a double bond is mainly used. A method for producing a vinyl chloride copolymer resin, wherein a macromonomer having a chain is charged, dispersed in initial water, and then a vinyl chloride monomer is charged (claim 1),
(2) The ratio of vinyl chloride monomer to the total amount of charged monomers is 50% by weight or more and less than 100% by weight, and the macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain and chloride The total weight (M) and initial water weight (H) of the vinyl monomer are within the range of the following formula (1): 0 <H / M ≦ 3.0 (1)
The method for producing a vinyl chloride copolymer resin according to claim 1 (claim 2),
(3) The vinyl chloride copolymer according to claim 1 or 2, wherein the water-soluble polymerization inhibitor is at least one selected from thiocyanate, nitrite, and a water-soluble sulfur-containing organic compound. A method for producing a polymerized resin (claim 3),
About.

  According to the present invention, the time required for recovering the vinyl chloride monomer after completion of the polymerization can be shortened. Moreover, according to this invention, foaming of a slurry can be suppressed at the time of vinyl chloride monomer collection | recovery after completion | finish of superposition | polymerization.

    With respect to the method for producing the vinyl chloride copolymer resin of the present invention, the initial water is put in advance in a polymerization machine or a dispersion mixing tank, a water-soluble polymerization inhibitor is put in it, and then doubled in the initial water. Disperse after or after the introduction of a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a bond in the main chain, and then add a vinyl chloride monomer to the ethylenically unsaturated containing a double bond. It is preferable to start a copolymerization reaction by dispersing and mixing a macromonomer having a polymer composed of monomers in the main chain and a vinyl chloride monomer.

  The water-soluble polymerization inhibitor used in the production of the vinyl chloride copolymer resin of the present invention stops the radical reaction in the aqueous phase during the polymerization reaction, and the minute amount of the vinyl chloride copolymer resin in the aqueous phase. It is sufficient that the effect of suppressing the generation of particles is manifested, preferably at least one selected from thiocyanate, nitrite, and water-soluble sulfur-containing organic compound, particularly preferably nitrite, most preferably nitrous acid. Sodium.

  The water-soluble polymerization inhibitor used in the present invention is based on 100 parts by weight of the total amount of monomer components of a macromonomer having a polymer composed of a vinyl chloride monomer and an ethylenically unsaturated monomer containing a double bond in the main chain. 0.0001 part or more and 0.001 part or less is preferable because formation of fine particles having a high macromonomer content is suppressed. Moreover, if it is 0.0001 part or more and 0.0005 part or less, since the time at the time of monomer collection | recovery can be shortened, without significantly reducing a polymerization rate, it is still more preferable.

  The dispersion mixing tank used in the present invention is not particularly limited as long as it is an apparatus capable of performing dispersion mixing. For example, a polymerization reactor may be used, or a container other than the polymerization reactor equipped with a jacket and a stirrer may be used. In addition, “dispersion” means a stirrer while or after the introduction of a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the initial water charged into a dispersion mixing tank or the like. And so on, to form droplets in water. “Dispersed and mixed” means that both a vinyl chloride monomer and a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain are uniformly mixed without any boundary. It will be impossible to distinguish.

  Here, the monomer component constituting the present invention is a macromonomer having a polymer composed of a vinyl chloride monomer and an ethylenically unsaturated monomer containing a double bond in the main chain, and these monomer components are dispersed and mixed. This is referred to as “charged monomer”, and the total amount of monomer components constituting it is referred to as “total amount of charged monomer”.

  "Initial water" used in the method for producing a vinyl chloride copolymer resin of the present invention comprises a vinyl chloride monomer or an ethylenically unsaturated monomer containing a double bond to a polymerization machine or a dispersion mixing tank. This is a part or the whole amount of the polymerization charge water that is added before introducing the macromonomer having the polymer in the main chain. The initial water amount is not particularly limited and may be any amount in which the macromonomer having a polymer composed of a vinyl chloride monomer or an ethylenically unsaturated monomer containing a double bond in the main chain is dispersed and mixed in the initial water. It is preferable that 1% to 100% by weight of the total weight of water is the initial water, more preferably 1% to 50% by weight of the total weight of the feed water, and more preferably 1% by weight of the total weight of the feed water. To an amount in the range of 30 to 30% by weight is particularly preferable because the dispersion and mixing time is short.

  The total weight (M) and initial water weight (H) of the macromonomer and vinyl chloride monomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain are 0 <H / M. ≦ 3.0 is preferable because a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain and a vinyl chloride monomer are easily dispersed and mixed, and 0 <H / M ≦ When the macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond dispersed in the initial water in the main chain is added to the initial water, the vinyl chloride monomer is added. Phase transformation occurs in the dispersion, the vinyl chloride monomer becomes a continuous phase, and the macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain and the vinyl chloride monomer Further preferred the dispersion mixing time is shortened and over.

  Moreover, it is preferable to adjust so that the dispersing agent adjusted beforehand in initial water may be more than 0 weight part and 0.1% or less with respect to 100 weight part of preparation monomer total amount, and contains a double bond after that. When a macromonomer having a polymer composed of an ethylenically unsaturated monomer in the main chain is introduced and dispersed in initial water, a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain is obtained. Even when the viscosity is high, droplets can be formed in the initial water and polymerization can proceed stably, and adhesion to the can, stirring blade and stirring shaft can be reduced, and to the recess in the reactor. This is preferable because it can reduce the intrusion. In addition, a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain after adjusting so that the dispersant is more than 0 part by weight and not more than 0.08 part by weight in initial water. When injected and dispersed in initial water, macromonomer droplets having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain are injected into the dispersion when the vinyl chloride monomer is added. It is more preferable because it easily causes phase transition and macromonomer droplets hardly remain.

  The small particle weight in the aqueous suspension was obtained by sieving the inside of the aqueous vinyl chloride copolymer resin suspension obtained by polymerization with a 200 mesh sieve (JIS Z8801-1 opening of 350 μm), and the passing liquid was 100 It is a ratio obtained by dividing the weight of the resin obtained by sufficiently drying at 100 ° C. the aqueous vinyl chloride copolymer resin suspension obtained by sufficiently drying at ℃ and measuring the weight. It is preferably less than 2% by weight. If it is less than 2% by weight, COD in the drainage during dehydration is reduced, which is preferable. Further, it is preferably 1.5% by weight or less because in the vinyl chloride monomer recovery step at the end of the polymerization, the rise of the slurry liquid level due to bubbles is reduced. When the content is 1% by weight or less, the blocking property of the product after drying is improved, which is most preferable.

  The dispersion temperature (internal temperature) when dispersing and mixing a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in a vinyl chloride monomer in the main chain is 10 ° C. or higher and 60 ° C. or lower. It is preferably 20 ° C. or higher and 50 ° C. or lower. A polymer composed of an ethylenically unsaturated monomer containing a double bond in a vinyl chloride monomer is maintained in the main chain while maintaining the pressure of the dispersion mixing vessel at a temperature suitable for dispersion mixing as 10 ° C or more and 60 ° C or less. The macromonomer which has can be disperse-mixed uniformly.

  The rate at which the macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain is introduced into the initial water is not particularly limited as long as it is in a dispersed state after the addition, and is continuously added. Any of a method, a method of batch loading, and a method of batch loading may be used. For example, when introducing a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a high-viscosity double bond in the main chain, in order to disperse it in the initial water, it can be added in small portions continuously. In addition, undispersed deposits and undissolved residues in the slurry are less likely to remain on the inner wall of a polymerization machine or a dispersion mixing tank.

  In the method for producing a vinyl chloride copolymer of the present invention, the rotational speed and dispersion time when dispersing a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in initial water in the main chain are as follows: There are no particular restrictions because it varies depending on the shape of the stirrer and the gap from the stirrer to the inner wall of the polymerization apparatus or dispersion mixing tank, but for example, the ratio of the paddle type stirrer diameter (d) to the polymerization apparatus diameter (D) (d / When D) is 3.0, the number of rotations is preferably 50 rpm or more.

  Further, the time for dispersing and mixing the macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the vinyl chloride monomer in the main chain is not particularly limited as long as it can be sufficiently dispersed and mixed. Is preferably 1 minute or longer. When it is 1 minute or longer, a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the vinyl chloride monomer as a main chain can be uniformly dispersed and mixed.

By these methods, by uniformly dispersing and mixing a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain with a vinyl chloride monomer,
For example, problems such as “copolymerization becomes abnormal polymerization and normal particles cannot be obtained” and “a large amount of scale occurs even when normal particles are obtained” can be suppressed.

  The vinyl chloride monomer used in the present invention is not particularly limited. For example, vinyl chloride monomer, vinylidene chloride monomer, vinyl acetate monomer, or a mixture thereof, or other copolymerizable with these, preferably after polymerization. A monomer having no reactive functional group in the polymer main chain, for example, one or a mixture of two or more selected from α-olefins such as ethylene and propylene may be used. When using 2 or more types of mixtures, it is preferable that the content rate of the vinyl chloride monomer which occupies for the whole vinyl chloride monomer is 50 weight% or more, especially 70 weight% or more. Among these, from the physical properties of the copolymer resin obtained, it is preferable to use only one of vinyl chloride monomer or vinylidene chloride monomer, and it is more preferable to use vinyl chloride monomer.

In general, a macromonomer is an oligomer molecule having a reactive functional group at the end of a polymer. The macromonomer having, in the main chain, a polymer composed of an ethylenically unsaturated monomer containing a double bond used in the present invention is an allyl group, a vinylsilyl group, a vinyl ether group, dicyclopentadienyl as a reactive functional group. It is produced by radical polymerization having at least one group having a polymerizable carbon-carbon double bond selected from the following general formula (1) at the molecular end.
In particular, since the reactivity with the vinyl chloride monomer is good, the group having a polymerizable carbon-carbon double bond is represented by the following general formula:
—OC (O) C (R) ═CH ₂
The group represented by these is preferable.

In the formula, specific examples of R are not particularly limited. For example, —H, —CH ₃ , —CH ₂ CH ₃ , — (CH ₂ ) _n CH ₃ (n represents an integer of 2 to 19), — A group selected from C ₆ H ₅ , —CH ₂ OH and —CN is preferred, and —H and —CH ₃ are more preferred.

  A polymer composed of an ethylenically unsaturated monomer containing a double bond, which is the main chain of the macromonomer used in the present invention, is produced by radical polymerization. The radical polymerization method uses “a general radical polymerization method” in which a monomer having a specific functional group and a vinyl monomer are simply copolymerized using an azo compound or a peroxide as a polymerization initiator, It is possible to classify into a “controlled radical polymerization method” in which a specific functional group can be introduced at a controlled position.

  In the “general radical polymerization method”, a monomer having a specific functional group is introduced into the polymer only in a probabilistic manner. Must be used in large quantities. Moreover, since it is free radical polymerization, it is difficult to obtain a polymer having a wide molecular weight distribution and a low viscosity.

  “Controlled radical polymerization method” further includes a “chain transfer agent method” in which a vinyl polymer having a functional group at a terminal is obtained by polymerization using a chain transfer agent having a specific functional group, It can be classified as a “living radical polymerization method” in which a polymer having a molecular weight almost as designed can be obtained by growing a growth terminal without causing a termination reaction or the like.

  The “chain transfer agent method” can obtain a polymer having a high functionalization rate, but requires a chain transfer agent having a specific functional group with respect to the initiator. Further, like the above-mentioned “general radical polymerization method”, since it is free radical polymerization, it is difficult to obtain a polymer having a wide molecular weight distribution and a low viscosity.

  Unlike these polymerization methods, the “living radical polymerization method” has a high polymerization rate due to coupling between radicals and the like as described in International Publication WO99 / 65963 relating to the applicant's own invention. Although radical polymerization is considered to be difficult to control because it tends to cause a termination reaction, the termination reaction is difficult to occur and the molecular weight distribution is narrow. For example, the ratio of the weight average molecular weight Mw to the number average molecular weight Mn (Mw / Mn) is 1. While a polymer of about 1 to 1.5 is obtained, the molecular weight can be freely controlled by the charging ratio of the monomer and the initiator.

  Accordingly, the “living radical polymerization method” can obtain a polymer having a narrow molecular weight distribution and a low viscosity, and a monomer having a specific functional group can be introduced at almost any position of the polymer. In the present invention, the method for producing a vinyl polymer having a specific functional group as described above is a more preferable polymerization method.

  Among “Living Radical Polymerization Methods”, “Atom Transfer Radical Polymerization (ATRP)” is a method in which vinyl halide monomers are polymerized using an organic halide or a sulfonyl halide compound as an initiator and a transition metal complex as a catalyst. In addition to the above-mentioned characteristics of the “living radical polymerization method”, it has a halogen which is relatively advantageous for functional group conversion reaction at the terminal, and has a large degree of freedom in designing initiators and catalysts. It is further preferable as a method for producing a vinyl-based polymer having Examples of this atom transfer radical polymerization method include Matyjaszewski et al., Journal of American Chemical Society (J. Am. Chem. Soc.) 1995, 117, 5614.

  There is no particular limitation as to which of these methods is used as a method for producing a macromonomer in the present invention, but usually a controlled radical polymerization method is used, and a living radical polymerization method is preferably used because of ease of control. In particular, the atom transfer radical polymerization method is most preferable.

  In addition, there is no particular limitation on the polymer composed of an ethylenically unsaturated monomer containing a double bond, which the macromonomer main chain used in the present invention has, and ethylene containing a double bond constituting the polymer. Various kinds of unsaturated unsaturated monomers can be used. For example, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid-n-propyl, (meth) acrylic acid isopropyl, (meth) acrylic acid-n-butyl, (meth ) Isobutyl acrylate, (meth) acrylic acid-tert-butyl, (meth) acrylic acid-n-pentyl, (meth) acrylic acid-n-hexyl, (meth) acrylic acid cyclohexyl, (meth) acrylic acid-n- Heptyl, (n-octyl) (meth) acrylate, (2-ethylhexyl) (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, phenyl (meth) acrylate, Toluyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, (meth) 3-methoxybutyl crylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, stearyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid 2 -Aminoethyl, γ- (methacryloyloxypropyl) trimethoxysilane, ethylene oxide adduct of (meth) acrylic acid, trifluoromethylmethyl (meth) acrylate, 2-trifluoromethylethyl (meth) acrylate, (meth ) 2-perfluoroethylethyl acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth) acrylate, 2-perfluoroethyl (meth) acrylate, perfluoromethyl (meth) acrylate, (meta ) Diperfluoromethyl methyl acrylate, (meth) acrylic 2-perfluoromethyl-2-perfluoroethyl methyl phosphate, 2-perfluorohexylethyl (meth) acrylate, 2-perfluorodecylethyl (meth) acrylate, 2-perfluorohexadecyl (meth) acrylate (Meth) acrylic acid monomers such as ethyl; styrene monomers such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene, styrenesulfonic acid and salts thereof; fluorine such as perfluoroethylene, perfluoropropylene, vinylidene fluoride -Containing vinyl monomers; silicon-containing vinyl monomers such as vinyltrimethoxysilane and vinyltriethoxysilane; maleic anhydride, maleic acid, monoalkyl esters and dialkyl esters of maleic acid; fumaric acid, monoalkyl esters of fumaric acid and dia Kill esters; maleimide monomers such as maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, cyclohexylmaleimide; containing nitrile groups such as acrylonitrile and methacrylonitrile Vinyl monomers; amide group-containing vinyl monomers such as acrylamide and methacrylamide; vinyl esters such as vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate and vinyl cinnamate; alkenes such as ethylene and propylene; butadiene And conjugated dienes such as isoprene; allyl chloride, allyl alcohol and the like. These may be used alone or two or more of them may be copolymerized. Of these, a styrene monomer or a (meth) acrylic acid monomer is preferred from the viewpoint of physical properties of the product. An acrylate monomer or a methacrylic acid ester monomer is more preferable, an acrylate monomer is more preferable, and butyl acrylate is most preferable. In the present invention, these preferable monomers may be copolymerized with other monomers, and in this case, it is preferable that these preferable monomers are contained in an amount of 40% or more by weight. Here, for example, “(meth) acrylic acid” means acrylic acid or methacrylic acid.

  The macromonomer used in the present invention has a polymer composed of an ethylenically unsaturated monomer containing these double bonds in the main chain, and further has at least one reactive functional group per molecule at the molecular end. It is characterized by having.

  Furthermore, only one type of macromonomer copolymerizable with the vinyl chloride monomer of the present invention may be used, or two or more types of macromonomers having different ethylenically unsaturated monomers may be used in combination.

  Further, the molecular weight of the macromonomer copolymerizable with the vinyl chloride monomer of the present invention is preferably a number average molecular weight in terms of styrene by GPC, and is 1,000 to 100,000. Furthermore, if it is 1000-30000, since a viscosity is low, since the microparticles | fine-particles with a high macromonomer content in the early stage of polymerization decrease, it is preferable. Moreover, if it is 1000-15000, since dispersion | distribution mixing time with a vinyl chloride monomer can be shortened and the vinyl chloride monomer recovery time after completion | finish of superposition | polymerization can be shortened, it is the most preferable.

  The ratio of the vinyl chloride monomer to the total amount of the monomer components constituting the vinyl chloride copolymer resin of the present invention is not particularly limited as long as the effect of the present invention is exhibited, but is 50 wt% or more and less than 100 wt%. Preferably, it is 50 to 99.95% by weight, more preferably 50 to 97% by weight. If the ratio of the vinyl chloride monomer is in the range of 50% by weight or more and less than 100% by weight, the copolymerization reaction is stable and the resulting vinyl chloride copolymer resin becomes a granular material, so that the processing method is free. The effect of increasing the degree can be expected.

  The average degree of polymerization or the average molecular weight of the vinyl chloride copolymer resin of the present invention is not particularly limited, and the K value measured according to JIS K 7367-2 is 50 to 95 as in the case of a vinyl chloride resin usually produced and used. Range. Moreover, as an average particle diameter, it is the range of 10-500 micrometers normally.

  The method for producing the vinyl chloride copolymer resin of the present invention is not particularly limited, but copolymerization in an aqueous medium is preferable from the viewpoint of simplicity of polymerization control such as removal of polymerization reaction heat and suppression of runaway reaction, It is preferable to use a suspension polymerization method.

  In the present invention, a vinyl chloride monomer is dispersed and mixed in a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain, and if necessary, a dispersion used in a suspension polymerization method. Agent, polymerization initiator, surfactant, dispersion aid, antioxidant, polymerization degree regulator, chain transfer agent, particle size regulator, pH regulator, gelling agent, antistatic agent, stabilizer, scale An inhibitor or the like is charged all at once, divided or continuously as required, and a copolymerization reaction is performed at a predetermined polymerization temperature.

  The dispersant used in the suspension polymerization method is not particularly limited as long as it does not impair the object of the present invention. Examples of such a dispersant include partially saponified polyvinyl acetate; water-soluble cellulose ethers such as methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and carboxymethylcellulose; polyethylene oxide; polyvinylpyrrolidone; polyacrylic acid; -Maleic acid copolymer; Styrene-maleic acid copolymer; Gelatin; Starch and other organic polymer dispersants can be used, and these can be used alone or in combination of two or more.

  In addition, the polymerization initiator is not particularly limited, and an oil-soluble polymerization initiator within a range that does not impair the object of the present invention may be added. Among these initiators, the 10-hour half-life temperature is 30 to 65 ° C. It is preferable to use one or more of them. Examples of such polymerization initiators include acetylcyclohexylsulfonyl peroxide, 2,4,4 trimethylpentyl-2-peroxyneodecanoate, diisopropyl peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate. , T-butyl peroxypivalate, t-butyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, dilauroyl peroxide, 3,5,5-trimethylhexa Organic peroxide polymerization initiators such as noyl peroxide; 2,2′-azobisisobutyronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2 ′ -Azo polymerization initiators such as -azobis- (2,4-dimethylvaleronitrile) These may be used alone or in combination of two or more. These oil-soluble polymerization initiators can be added without any particular restrictions. For example, when used by dissolving in an organic solvent, examples of the organic solvent include aromatics such as toluene, xylene, and benzene. Hydrocarbons; Aliphatic hydrocarbons such as hexane and isoparaffin; Ketones such as acetone and methyl ethyl ketone; Esters such as ethyl acetate, butyl acetate and dioctyl phthalate are used, and these should be used alone or in combination of two or more. Can do.

  In addition, antioxidants, polymerization degree regulators, chain transfer agents, particle size regulators, pH regulators, gelling modifiers, antistatic agents, stabilizers, scale inhibitors, etc. are generally used in the production of vinyl chloride resins. What is used for can be used arbitrarily as needed, and the amount charged is not particularly limited.

  In general, vinyl chloride resins are used for various purposes, and a resin manufactured by a manufacturing method suitable for the application is used. For example, vinyl chloride resins produced mainly by suspension polymerization are used for hard applications such as pipes, joints, and plates, and soft applications such as sheets, films, and wire coatings. The vinyl chloride resin production method of the present invention can be suitably used for any of these production methods, and according to the present invention, vinyl chloride copolymer resins suitable for various applications can be obtained.

  EXAMPLES Although this invention is demonstrated in detail based on an Example, this invention is not limited to a following example. Here, unless otherwise specified, “parts” in the examples means “parts by weight” and “%” means “% by weight”.

<Evaluation of 200 mesh sieving (small particle amount)>
The obtained slurry was sieved with a 200-mesh sieve (JIS Z8801-1 opening 350 μm), the passing liquid was sufficiently dried at 100 ° C., and the weight was measured (weight of slurry 200-mesh sieve passed dry resin). On the other hand, the weight of the solid content obtained by sufficiently drying the obtained slurry at 100 ° C. was measured (total slurry dry resin weight), and the 200 mesh sieve passing resin ratio was calculated by the following calculation formula.

(Ratio of resin passing through 200 mesh sieve) = (weight of slurry passing through 200 mesh sieve) / (weight of all slurry dry resin)
A 200 mesh sieve passing resin ratio is preferably less than 2% because the COD in the drainage during dehydration is reduced.

<Quantification of macromonomer content in resin>
1 g of the whole slurry or a dried product obtained by drying a liquid passing through a 200 mesh sieve at 100 ° C. was dissolved in 30 g of a special grade THF (tetrahydrofuran) reagent, and the solution was applied to a KBr plate and dried, and then an IR measuring machine (Perkin Elmer). absorption was measured 400 cm ^-1 from 4000 cm ^-1 in manufacturing a Fourier transform infrared spectrophotometer SPECRUM1000). A signal derived from the carbonyl group (peak top in the vicinity of 1730 cm ^-1), carbon - draw a calibration curve ratio of the peak height relative to the macromonomer content relative baseline chlorine from the signal (peak top in the vicinity of 615 cm ^-1) By measuring the IR of the sample, the macromonomer content in the total resin and the small particle resin was calculated, respectively.
<Slurry pressure recovery time>
An ultrasonic liquid level detector was inserted in the polymerization machine in advance, and recovery was performed while checking the level of the gas-liquid interface (foam liquid level). In order not to exceed the space of the polymerization machine (so that bubbles do not flow in the collection line), the opening of the collection valve is adjusted, and when the polymerization machine internal pressure becomes 0.05 MPa or less, it is switched to a vacuum pump. When the pressure reaches 0.05 MPa, the pressure is returned to 0 MPa with nitrogen. The time from the start of recovery to the pressure return with nitrogen is defined as the recovery time. The liquid level (level) is L / (L100−L0) × 100, where L0 is the liquid level before recovery, L100 is the liquid volume obtained by dividing the space volume of the polymerization apparatus by the cross-sectional area, and L is the height of bubbles at the time of recovery. As [%], the highest liquid level during the collection period is defined as Lmax.
<Manufacture of a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain>
Production of a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain was carried out according to the procedure shown in the following production example.

(Production example)
CuBr (5.54 g) was charged into a 2 L separable flask equipped with a reflux tube and a stirrer, and the inside of the reaction vessel was purged with nitrogen. Acetonitrile (73.8 ml) was added, and the mixture was stirred in an oil bath at 70 ° C. for 30 minutes. To this, n-butyl acrylate (132 g), methyl 2-bromopropionate (7.2 ml) and pentamethyldiethylenetriamine (4.69 ml) were added to initiate the reaction. While heating and stirring at 70 ° C., acrylate-n-butyl (528 g) was continuously added dropwise over 90 minutes, and the mixture was further heated and stirred for 80 minutes.

  The reaction mixture was diluted with toluene, passed through an activated alumina column, and then the volatile component was distilled off under reduced pressure to obtain one-terminal Br group poly (acrylic acid-n-butyl).

The flask was charged with methanol (800 ml) and cooled to 0 ° C. Thereto, t-butoxypotassium (130 g) was added in several portions. The reaction solution was kept at 0 ° C., and a methanol solution of acrylic acid (100 g) was added dropwise. After completion of the dropwise addition, the temperature of the reaction solution was returned from 0 ° C. to room temperature, and then the volatile content of the reaction solution was distilled off under reduced pressure to obtain potassium acrylate (CH ₂ = CHCO ₂ K).

A 500 mL flask equipped with a reflux tube was charged with the obtained one-terminal Br group poly (acrylic acid-n-butyl) (150 g), potassium acrylate (7.45 g), dimethylacetamide (150 ml), and heated at 70 ° C. for 3 hours. Stir. Dimethylacetamide was distilled off from the reaction mixture, dissolved in toluene, passed through an activated alumina column, and then toluene was distilled off to obtain a one-terminal acryloyl group poly (acrylic acid-n-butyl) macromonomer.
The viscosity of the one-end acryloyl group poly (acrylic acid-n-butyl) macromonomer at 25 ° C. was about 40 Pa · s.

Example 1
A stainless steel polymerization reactor having a volume of 25 liters equipped with a jacket and a stirrer is charged with 40 parts of water as the initial water in advance, and partially saponified with a degree of saponification of about 80 mol% and an average degree of polymerization of about 2000. 0.02 part of polyvinyl acetate was added, the polymerization reactor internal temperature was controlled at 20 ° C., and the mixture was dissolved while stirring at a rotation speed of 900 revolutions per minute. After adding 0.00015 part of sodium nitrite and stirring, 40 parts of acryloyl group poly (n-butyl acrylate) macromonomer of Production Example was charged and degassed, and then 60 parts of vinyl chloride monomer was added. The macromonomer was dispersed and mixed in the vinyl chloride monomer by stirring for 10 minutes after charging and charging. After adding 0.03 part of t-butylperoxyneodecanoate and 0.01 part of 1,1,3,3-tetramethylbutylperoxyneodecanoate, the degree of saponification was about 80 mol% and the average degree of polymerization. 0.08 part of partially saponified polyvinyl acetate having a molecular weight of about 2000 and 0.005 part of polyethylene oxide having an average molecular weight of about 4.5 million were charged together with 110 parts of hot water at 60 ° C. and polymerized at a polymerization temperature of 57 ° C. for about 6 hours. Self-pressure recovery was started by controlling the jacket temperature at 57 ° C. The recovery time was 0.5 hours and Lmax was 90%. Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Example 2)
A stainless steel polymerization reactor having a volume of 25 liters equipped with a jacket and a stirrer is charged with 100 parts of water in advance as the initial water, and partially saponified with a degree of saponification of about 80 mol% and an average degree of polymerization of about 2000. 0.01 parts of polyvinyl acetate was dissolved while stirring at a rotational speed of 450 revolutions per minute while controlling the internal temperature of the polymerization reactor at 40 ° C. While stirring, 0.00015 part of sodium nitrite was added, 6 parts of acryloyl group poly (n-butyl acrylate) macromonomer of Production Example was charged, degassed, and 94 parts of vinyl chloride monomer was added. The macromonomer was dispersed and mixed in the vinyl chloride monomer by stirring for 15 minutes after charging and charging. After adding 0.03 part of t-butylperoxyneodecanoate and 0.01 part of 1,1,3,3-tetramethylbutylperoxyneodecanoate, the degree of saponification was about 80 mol% and the average degree of polymerization. 0.04 part of partially saponified polyvinyl acetate having a molecular weight of about 2000 and 0.005 part of polyethylene oxide having an average molecular weight of about 4.5 million were charged together with 50 parts of hot water at 60 ° C. and polymerized at a polymerization temperature of 57 ° C. for about 6 hours. Self-pressure recovery was started by controlling the jacket temperature to 65 ° C. The recovery time was 0.4 hours and Lmax was 70%. Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Example 3)
A stainless steel polymerization reactor with an internal capacity of 1500 liters equipped with a jacket and a stirrer is charged with 300 parts of water as initial water in advance, and partially saponified with a degree of saponification of about 80 mol% and an average degree of polymerization of about 2000. 0.01 part of polyvinyl acetate and 0.005 part of polyethylene oxide having an average molecular weight of about 4.5 million were dissolved while stirring at a rotational speed of 560 revolutions per minute while controlling the internal temperature of the polymerization reactor at 25 ° C. While stirring, 0.00015 part of sodium nitrite was added, and after 3 parts of acryloyl group poly (acrylic acid-n-butyl) macromonomer of Production Example was charged and degassed, 97 parts of vinyl chloride monomer were added. The macromonomer was dispersed and mixed in the vinyl chloride monomer by stirring for 20 minutes after charging and charging. After charging 0.0075 part of t-butylperoxyneodecanoate and 0.02 part of t-hexylperoxypivalate, then partially saponified polyvinyl acetate having a saponification degree of about 80 mol% and an average degree of polymerization of about 2000 0.05 part of polyethylene oxide (0.005 part) having an average molecular weight of about 4.5 million was charged together with 50 parts of hot water at 60 ° C. and polymerized at a polymerization temperature of 66.5 ° C. for about 5.5 hours. The jacket temperature was controlled at 66.5 ° C., and self-pressure recovery was started. The recovery time was 2 hours and Lmax was 85%. Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

Example 4
A stainless steel polymerization reactor having a capacity of 1500 liters equipped with a jacket and a stirrer is preliminarily charged with 20 parts of water as the initial water, and partially saponified with a degree of saponification of about 80 mol% and an average degree of polymerization of about 2000. 0.016 parts of polyvinyl acetate was dissolved while stirring at a rotational speed of 560 revolutions per minute while controlling the internal temperature of the polymerization reactor at 25 ° C. While stirring, 0.00030 part of sodium nitrite was added, 10 parts of acryloyl group poly (acrylic acid-n-butyl) macromonomer of Production Example was charged, degassed, and 90 parts of vinyl chloride monomer was added. The macromonomer was dispersed and mixed in the vinyl chloride monomer by stirring for 30 minutes after charging and charging. After charging 0.0075 part of t-butylperoxyneodecanoate and 0.02 part of t-hexylperoxypivalate, then partially saponified polyvinyl acetate having a saponification degree of about 80 mol% and an average degree of polymerization of about 2000 0.084 parts 60 parts of warm water of 130 ° C. was charged and polymerized at a polymerization temperature of 66.5 ° C. for about 5.5 hours. The jacket temperature was controlled at 75 ° C. and self-pressure recovery was started. The recovery time was 1.5 hours and Lmax was 80%. Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Comparative Example 1)
Preparation and polymerization were carried out in the same manner as in Example 1 except that the sodium nitrite of Example 1 was changed from 0.00015 part to 0 part. After 6 hours of polymerization, the jacket temperature was controlled at 57 ° C., and autogenous pressure recovery was started. Since the pressure was released slowly so that bubbles (slurry) did not scatter from the polymerization machine due to sudden pressure release, the recovery time took 1 hour and Lmax was 100% (a part of the bubbles flowed from the polymerization machine to the recovery line). ) Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Comparative Example 2)
The charging and polymerization were carried out in the same manner as in Example 1 except that the sodium nitrite of Example 1 was changed from 0.00015 part to 0.002 part. After 6 hours of polymerization, the pressure inside the can was still higher than in Example 1 (it was judged that more vinyl chloride monomer remained and no vinyl chloride monomer was consumed in the same polymerization time), but the jacket temperature was 57 ° C. The self-pressure recovery was started under the control. In the same polymerization time as in Example 1, no sufficient pressure drop was observed (polymerization delay), and the pressure was slowly released so that bubbles (slurry) did not scatter from the polymerization machine due to rapid pressure release. It took 2.5 hours and Lmax was 100% (a part of the bubbles flowed from the polymerization machine to the recovery line). Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Comparative Example 3)
Preparation and polymerization were carried out in the same manner as in Example 4 except that the sodium nitrite of Example 4 was changed from 0.00030 part to 0 part. After 5.5 hours of polymerization, the jacket temperature was controlled at 66.5 ° C., and auto-pressure recovery was started. Since the pressure was released slowly so that bubbles (slurry) did not scatter from the polymerizer due to sudden pressure release, the recovery time took 5 hours, and Lmax was 100% (a part of the bubbles flowed from the polymerizer to the recovery line). ) Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

(Comparative Example 4)
Preparation and polymerization were performed in the same manner as in Example 4 except that the sodium nitrite of Example 4 was changed from 0.00030 part to 0.0015 part. After 5.5 hours of polymerization, the pressure inside the can was still higher than in Example 1 (it was judged that more vinyl chloride monomer remained and no vinyl chloride monomer was consumed in the same polymerization time). The jacket temperature was controlled at 66.5 ° C., and self-pressure recovery was started. In the same polymerization time as in Example 4, no sufficient pressure drop was observed (polymerization delay), and the pressure was slowly released so that bubbles (slurry) did not scatter from the polymerization machine due to rapid pressure release, so the recovery time was It took 4 hours and Lmax was 100% (a part of the bubbles flowed from the polymerization machine to the recovery line). Table 1 shows the results of the self-pressure recovery / polymerization resin evaluation.

Claims (3)

When copolymerizing a vinyl chloride monomer and a macromonomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain to produce a vinyl chloride copolymer resin by suspension polymerization,
After adjusting the amount of the dispersant in the initial water to be more than 0 parts by weight and 0.1 parts by weight or less with respect to 100 parts by weight of the total amount of monomer components (hereinafter referred to as “total amount of charged monomers”), After the water-soluble polymerization inhibitor is added in an amount of 0.0001 part or more and 0.001 part or less with respect to 100 parts by weight of the total amount of charged monomers, a polymer composed of an ethylenically unsaturated monomer containing a double bond is mainly used. A method for producing a vinyl chloride copolymer resin, wherein a macromonomer having a chain is introduced, dispersed in initial water, and then a vinyl chloride monomer is added. The ratio of vinyl chloride monomer to the total amount of charged monomers is 50% by weight or more and less than 100% by weight, and the macromonomer and vinyl chloride monomer having a polymer composed of an ethylenically unsaturated monomer containing a double bond in the main chain The total weight (M) and the initial water weight (H) are in the range of the following formula (1): 0 <H / M ≦ 3.0 (1)
The method for producing a vinyl chloride copolymer resin according to claim 1, wherein:   3. The vinyl chloride copolymer resin according to claim 1, wherein the water-soluble polymerization inhibitor is at least one selected from thiocyanate, nitrite, and a water-soluble sulfur-containing organic compound. Production method.