JP2019065152A - Method for producing chlorinated vinyl chloride-based resin - Google Patents

Abstract

To provide a method for producing a chlorinated vinyl chloride-based resin that can produce a chlorinated vinyl chloride-based resin having a small amount of residual impurities such as hydrogen chloride and the like and having high thermal stability.SOLUTION: The method for producing a chlorinated vinyl chloride-based resin has a step of adding at least one carbonic acid-based compound selected from the group consisting of carbonate and hydrogencarbonate, and a hydroxypolycarboxylic acid salt to a chlorinated vinyl chloride-based resin and when the chlorinated vinyl chloride-based resin is 100 pts.wt., the addition amount of the carbonic acid-based compound is 0.015 pt.wt. to 0.2 pt.wt.; the addition amount of the hydroxypolycarboxylic acid salt is 0.015 pt.wt. to 0.2 pt.wt.; and the total addition amount of the carbonic acid-based compound and the hydroxypolycarboxylic acid salt is 0.03 pt.wt. to 0.3 pt.wt..SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a chlorinated vinyl chloride resin. In detail, a chlorine compound having a small amount of residual hydrogen chloride and excellent in static thermal stability is obtained by adding a carbonic acid compound and a hydroxypolycarboxylate in a predetermined amount range to a powder of a chlorinated vinyl chloride resin. The present invention relates to a method for producing a chlorinated vinyl chloride resin from which a chlorinated vinyl chloride resin is obtained.

  The chlorinated vinyl chloride resin becomes higher in heat resistance temperature than the vinyl chloride resin by being chlorinated. Therefore, chlorinated vinyl chloride resins are used in various fields such as heat resistant pipes, heat resistant industrial boards, heat resistant films and heat resistant sheets.

  Chlorinated vinyl chloride resin is obtained by chlorinating vinyl chloride resin, but in the reaction to form chlorinated vinyl chloride resin using vinyl chloride resin and chlorine, it is chlorinated as shown in the following equation. Hydrogen is by-produced.

  Therefore, it is usually necessary to remove hydrogen chloride, which is an impurity when shipped in powder form, for chlorinated vinyl chloride resins.

  In particular, if the chlorinated vinyl chloride resin in a state in which a large amount of hydrogen chloride (for example, 300 ppm or more) remains, is stored for a long time in a metal silo to which no countermeasure such as Teflon (registered trademark) processing is applied. The inside may be corroded by the effect of hydrogen chloride exuding, or if the metal pipe or screw in the hopper is passed to process the resin, the pipe or screw may be corroded. If the rust produced by this corrosion is mixed in the chlorinated vinyl chloride resin powder, there is a possibility that the final product may be affected as foreign matter or impurities.

  Therefore, in Patent Document 1, as a means for removing hydrogen chloride, one or two or more kinds of inorganic alkali metal salts such as sodium hydroxide, calcium hydroxide, sodium carbonate, sodium hydrogencarbonate and calcium carbonate as alkalis are added. Although the method of neutralizing is performed, in order not to impair heat stability, it is proposed to make the metal total amount of inorganic salt 50 ppm or less.

  On the other hand, Patent Document 2 proposes that a hydroxypolycarboxylate is added as a means for improving the thermal stability of a chlorinated vinyl chloride resin.

JP 2000-239320 A Unexamined-Japanese-Patent No. 2000-143923

  However, in patent document 1, since the addition amount of an alkali is reduced so that a metal total amount may be 50 ppm or less, there exists a possibility that removal of hydrogen chloride of chlorinated vinyl chloride-type resin may be inadequate.

  In Patent Document 2, a hydroxypolycarboxylic acid salt is used to improve the thermal stability of the chlorinated vinyl chloride resin, but hydrogen chloride remains as an impurity and the quality of the chlorinated vinyl chloride resin is impaired. There is a risk of

  In order to solve the above-mentioned conventional problems, the present invention provides a method for producing a chlorinated vinyl chloride-based resin capable of obtaining a chlorinated vinyl chloride-based resin having a small amount of residual impurities such as hydrogen chloride and high thermal stability. .

  The present invention comprises the step of adding to a chlorinated vinyl chloride resin at least one carbonic acid compound selected from the group consisting of carbonates and hydrogencarbonates, and a hydroxypolycarboxylate, The amount of the carbonic acid compound added is 0.015 parts by weight or more and 0.2 parts by weight or less, and the amount of the hydroxypolycarboxylate added is 0.015 parts by weight or more when the amount of the resin is 100 parts by weight. And 2. 2 parts by weight or less, and the total addition amount of the carbonic acid compound and the hydroxypolycarboxylic acid salt is 0.03 parts by weight or more and 0.3 parts by weight or less. The present invention relates to a method of producing a resin.

  The carbonic acid compound is a hydrogen carbonate, and when the chlorinated vinyl chloride resin is 100 parts by weight, the amount of the hydrogen carbonate added is 0.015 parts by weight or more and 0.2 parts by weight or less preferable.

  The carbonate compound is a carbonate, and when the chlorinated vinyl chloride resin is 100 parts by weight, the addition amount of the carbonate is preferably 0.015 parts by weight or more and 0.1 parts by weight or less.

  The chlorinated vinyl chloride resin is preferably obtained by performing a chlorination reaction by bringing a powder of a vinyl chloride resin into contact with chlorine gas.

  The carbonate compound is preferably at least one selected from the group consisting of alkali metal carbonates, alkali metal bicarbonates, alkaline earth metal carbonates and alkaline earth metal bicarbonates.

  The hydroxypolycarboxylate is preferably sodium tartrate.

  It is preferable that the said carbonic acid type compound is sodium hydrogencarbonate.

  According to the production method of the present invention, it is possible to obtain a hydrogenated vinyl chloride resin having a high thermal stability, with little residual impurities such as hydrogen chloride.

FIG. 1 is a schematic side sectional view of an example of a reaction apparatus used for chlorination reaction at the time of production of chlorinated vinyl chloride resin. FIG. 2 is a schematic view of an example of a fluidized bed type reactor used for the chlorination reaction during the production of chlorinated vinyl chloride resin. FIG. 3 is a schematic view of an experimental apparatus used to measure the corrosion rate.

  The inventors of the present invention diligently studied to obtain a chlorinated vinyl chloride resin having a small amount of residual hydrogen chloride and good static thermal stability. As a result, by using a carbonic acid compound and a hydroxypolycarboxylic acid salt in combination and adding a predetermined amount of the carbonic acid compound and hydroxypolycarboxylic acid salt to the chlorinated vinyl chloride resin, the amount of residual hydrogen chloride is small and static It has been found that a chlorinated vinyl chloride resin having good heat stability can be obtained, and the present invention has been made.

  On the other hand, when inorganic alkali metal salts other than carbonic acid compounds, such as sodium hydroxide and hydroxypolycarboxylate, are used in combination, the effect of reducing hydrogen chloride and the effect of enhancing static thermal stability can not both be achieved. The The combination of the effect of reducing hydrogen chloride and the effect of enhancing static thermal stability was unique to the combined use of a carbonate compound and a hydroxypolycarboxylate.

  In the present invention, the carbonic acid compound refers to a carbonate which is a compound containing a carbonate ion and a hydrogen carbonate which is a compound containing a hydrogen carbonate ion. The said carbonic acid type compound may be used individually by 1 type, and may be used in combination of 2 or more types.

  In the present invention, the hydrogencarbonate is not particularly limited, and examples thereof include hydrogencarbonates of alkali metals, hydrogencarbonates of alkaline earth metals, cadmium hydrogencarbonate, ammonium hydrogencarbonate and the like. Examples of the alkali metal hydrogen carbonate include potassium hydrogen carbonate and sodium hydrogen carbonate. Examples of the alkaline earth metal hydrogen carbonate include calcium hydrogen carbonate and the like. When it is used by dissolving it in an aqueous solution, sodium hydrogen carbonate is preferably used in view of water solubility, safety, low price and easy availability. Sodium hydrogen carbonate is preferably used because it does not adversely affect the human body even if it remains when processing a chlorinated chlorinated vinyl resin into a final product.

  The hydrogen carbonate may be used alone or in combination of two or more.

  The amount of the hydrogen carbonate added is 0.015 parts by weight or more and 0.2 parts by weight or less based on 100 parts by weight of the chlorinated vinyl chloride resin from the viewpoint of further reducing the residual amount of hydrogen chloride. The amount is preferably 0.02 parts by weight or more and 0.2 parts by weight or less, and more preferably 0.05 parts by weight or more and 0.2 parts by weight or less.

  In the present invention, the carbonate is not particularly limited, and examples thereof include alkali metal carbonates, alkaline earth metal carbonates, copper carbonate, iron carbonate, ammonium carbonate and silver carbonate. Examples of carbonates of alkali metals include potassium carbonate, sodium carbonate and lithium carbonate. Examples of carbonates of alkaline earth metals include calcium carbonate, magnesium carbonate and barium carbonate. When it is used by dissolving it in an aqueous solution, sodium carbonate or potassium carbonate is preferably used because of its water solubility, safety, low price and easy availability. Sodium carbonate and potassium carbonate are preferably used because they do not adversely affect the human body, even if they remain when processing the chlorinated vinyl chloride resin into a final product.

  The said carbonate may be used individually by 1 type, and may be used in combination of 2 or more types.

  The amount of the carbonate added is preferably 0.015 parts by weight or more and 0.1 parts by weight or less from the viewpoint of further reducing the residual amount of hydrogen chloride when 100 parts by weight of the chlorinated vinyl chloride resin is used. The content is more preferably 0.02 parts by weight or more and 0.1 parts by weight or less, still more preferably 0.05 parts by weight or more and 0.1 parts by weight or less.

  In the present invention, the hydroxypolycarboxylic acid salt is not particularly limited. For example, tartrate salt, malate salt, tartronic acid salt, α-methyl malate salt, tetrahydroxysuccinic tartrate salt, citrate, 1,2- Dihydroxy-1,1,2-ethane tricarboxylate etc. can be used. When it is used by dissolving it in an aqueous solution, sodium tartrate and the like are preferably used in view of water solubility, safety, low price and easy availability. These are not particularly limited, and any of hydrates and anhydrides may be used.

  The hydroxypolycarboxylates may be used alone or in combination of two or more.

  The amount of the hydroxypolycarboxylate added is preferably 0.015 parts by weight or more and 0.2 parts by weight or less, based on 100 parts by weight of the chlorinated vinyl chloride resin, and is not particularly limited. The amount is preferably 0.02 parts by weight or more and 0.2 parts by weight or less, and more preferably 0.05 parts by weight or more and 0.2 parts by weight or less from the viewpoint of further enhancing the stability.

  In the present invention, the addition total amount of the carbonate compound and the hydroxypolycarboxylate is 0.03 parts by weight or more and 0.3 parts by weight or less based on 100 parts by weight of a chlorinated vinyl chloride resin. Although not particularly limited, for example, from the viewpoint of further reducing the residual amount of hydrogen chloride and further enhancing the thermal stability, it is preferably 0.04 parts by weight or more and 0.3 parts by weight or less.

  In the present invention, a chlorinated vinyl chloride resin is obtained by chlorinating a vinyl chloride resin. The vinyl chloride resin may be a homopolymer of a vinyl chloride monomer, or may be a copolymer of a vinyl chloride monomer and another copolymerizable monomer. Examples of other copolymerizable monomers include, but are not limited to, ethylene, propylene, vinyl acetate, allyl chloride, allyl glycidyl ether, acrylic acid ester, vinyl ether and the like.

  The method for producing the vinyl chloride resin is not particularly limited. For example, it may be obtained by any method such as suspension polymerization, bulk polymerization, gas phase polymerization, emulsion polymerization and the like.

  In the present invention, the method for producing a chlorinated vinyl chloride resin by chlorinating a vinyl chloride resin by chlorination reaction is not particularly limited. For example, a vinyl chloride resin and water may be supplied to the vinyl chloride resin. Water suspension method performed by supplying chlorine to an aqueous suspension that is a mixture liquid with water, or gas-solid contact method performed by directly blowing chlorine into powder of vinyl chloride resin, etc. It may be obtained by Although it is not particularly limited, it is suitably used for the gas-solid contact method which does not include a water washing step and often contains unreacted chlorine and hydrogen chloride which is a by-product inside and / or on the surface of particles.

  In the present invention, the method for gas-solid contact is not particularly limited. For example, a method of supplying a chlorine-containing gas to a container rotating type reactor such as a rotary kiln filled with a vinyl chloride resin, a ribbon mixer Such method of supplying chlorine-containing gas to a mechanical stirring type reactor, method of supplying powder of vinyl chloride resin in a stream of chlorine-containing gas, or chlorine-containing by a gas distributor installed at the lower part of the reactor There is a method of using a fluidized bed type reactor in which gas is dispersed and fluidized in powder of vinyl chloride resin in the reactor by dispersed chlorine containing gas. Among these, the method using a fluidized bed type reactor is preferable because the contact efficiency between the vinyl chloride resin and the chlorine-containing gas is high.

  In the present invention, for example, while supplying chlorine to a vinyl chloride resin, the vinyl chloride resin is irradiated with ultraviolet rays to chlorinate the vinyl chloride resin to obtain a chlorinated vinyl chloride resin. The role of ultraviolet light is to excite chlorine to generate chlorine radicals to promote the chlorine addition reaction to a vinyl chloride resin. Since chlorine has a strong absorption band to ultraviolet rays in the wavelength range of 280 nm to 420 nm, chlorine is irradiated with ultraviolet rays in the wavelength range of 280 nm to 420 nm while contacting vinyl chloride resin powder with chlorine gas. Preferably, the reaction is carried out. The ultraviolet light to be irradiated may include light with a wavelength of less than 280 nm or more than 420 nm, but from the viewpoint of energy efficiency, it is preferable to use a light source that emits a large amount of ultraviolet light in the wavelength range of 280 nm to 420 nm as a light source. . Specifically, low pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, metal halide lamps, ultraviolet LEDs, organic EL, inorganic EL and the like can be mentioned. More preferably, the wavelength range of the ultraviolet radiation is 280 nm or more and 420 nm or less, and in particular, the light source is an ultraviolet LED, an organic EL and an inorganic EL from the viewpoint It is preferable that it is 1 or more types chosen from the group which consists of. The light source may be disposed in the protective container depending on the purpose of protection of the light source, cooling and the like. The material of the protective container of the light source may be any as long as it does not prevent the irradiation of the ultraviolet light from the light source. For example, although a material such as quartz, Pyrex (registered trademark) glass, hard glass, soft glass, etc. can be used for a protective container of a light source, a wavelength in an ultraviolet range effective for chlorination reaction is effectively used Preferably, quartz or Pyrex (registered trademark) glass is used.

  In the present invention, the light source for irradiating ultraviolet light may be any one as long as the vinyl chloride resin powder can be irradiated with ultraviolet light, and the installation method is not particularly limited, and may be arranged outside the reactor, arranged inside the reactor You may When the light source is placed inside the reactor, all or part of the light source may be inserted into the vinyl chloride resin powder layer. From the viewpoint of preventing the corrosion by chlorine, the light source is preferably installed inside the reactor while being disposed in the protective container. For example, when the size of the reactor that performs the chlorination reaction is small, it is easy to obtain a large light receiving area of the vinyl chloride resin, and it is efficient if ultraviolet rays are irradiated from the outside of the powder bed or the outside of the reactor. . On the other hand, when the reactor is upsized in order to carry out the chlorination reaction on a commercial scale, inserting a light source inside the powder layer from the viewpoint of efficiently irradiating the vinyl chloride resin with ultraviolet light. preferable.

  The temperature in the reactor for carrying out the chlorination reaction of the vinyl chloride resin is not particularly limited, but the deterioration of the vinyl chloride resin and the coloring of the chlorinated vinyl chloride resin are prevented while facilitating the flow of the vinyl chloride resin. In light of the above, the temperature is preferably 10 ° C. or more and 100 ° C. or less, and more preferably 25 ° C. or more and 85 ° C. or less. Further, since the chlorination reaction of the vinyl chloride resin is an exothermic reaction, it is preferable to remove the heat from the powder layer to keep the temperature in the reactor within the above-mentioned range. The heating or heat removal of the powder layer can be performed, for example, by passing hot water or cooling water through a jacket attached to the outside of the reactor or a heat transfer tube disposed in the reactor.

  Hereinafter, the chlorination reaction step by the gas-solid contact method will be described using the drawings. In the present invention, for example, a vinyl chloride resin powder is brought into contact with chlorine gas using a reaction apparatus shown in FIG. 1, and a chlorination reaction is performed under irradiation of ultraviolet rays to produce a chlorinated vinyl chloride resin. be able to.

  FIG. 1 is a schematic side sectional view of an example of a reaction apparatus used for chlorination reaction at the time of production of chlorinated vinyl chloride resin. In this reactor, the gas coming out of the nitrogen cylinder 11 and the chlorine cylinder 12 is adjusted by the flow rate adjusting valve 13 so that the flow meter 14 has a predetermined value, and the wetting bin 16 temperature controlled by the water bath 15 contains chlorine. By passing (bubbling) the gas, a chlorine-containing gas containing a predetermined amount of water vapor is supplied to the fluidized bed reactor 17. In order to prevent the temperature change from the outside, the fluidized bed reactor 17 can also be kept warm by flowing warm water having the same temperature as the powder temperature in the fluidized bed jacket 18.

  Under the irradiation of ultraviolet rays from the ultraviolet irradiation device (light source) 22, the chloride in the chlorine-containing gas supplied from the vinyl chloride resin powder 102 in the fluidized bed reactor 17 and the wet bottle 16 is reacted to react with chloride. The chlorination reaction of the vinyl resin powder 102 is performed. When the position of the ultraviolet irradiation device 22 and the fluidized bed reactor 17 is close to the reactor, the temperature in the reactor is affected by the heat of the UV light source, and high power is required to obtain the necessary UV intensity when it is far. It is preferable to maintain a distance of 2 cm or more and 30 cm or less because a UV light source of The internal temperature of the fluidized bed reactor 17 rises with the start of the chlorination reaction, but the temperature in the fluidized bed reactor 17 is continuously measured by the thermocouple 107 and adjusted to a predetermined temperature. In the temperature adjustment, for example, the temperature in the fluidized bed reactor 17 may be adjusted by flowing cooling water through the heat transfer pipe 108. During the chlorination reaction, it is preferable to adjust the temperature in the fluidized bed reactor 17 to be 50 degrees or more and 80 degrees or less. 80 vol% or more is preferable, as for the chlorine concentration of the said chlorine containing gas, 99 vol% or more is more preferable, and 100 vol% is more preferable. The gas discharged from the hydrogen chloride absorption vessel 19 is excluded by the chlorine absorption vessel 20.

  FIG. 2 is a schematic view of a fluidized bed reactor 17. The fluidized bed reactor 17 is a Pyrex (registered trademark) glass double circular tube (φ 80 mm), and has a glass sintered body 101 for gas dispersion inside. The vinyl chloride resin 102 is charged inside, and it is fluidized by the gas flowing in from the gas inlet 103 at the lower part of the reactor, and the gas is discharged from the gas outlet 104 at the upper part of the reactor. The ultraviolet light is irradiated from the ultraviolet irradiation device 22, passes through the ultraviolet transmitting wall 105 and the warm water 106 for preventing external cooling, and is irradiated to the vinyl chloride resin 102 in the reactor.

  The chlorination reaction is terminated when the chlorination reaction rate reaches a predetermined value. The reaction rate of chlorination reaction is preferably 40% to 70%, more preferably 50% to 60%, and more preferably 53% to 55%.

  The chlorination reaction rate is as follows: 1 mole (62.5 g) of a vinyl chloride resin and 1 mole (71 g) of chlorine react to form 1 mole (97 g) of a chlorinated vinyl chloride resin and 1 mole (36. The case where 5 g) is generated is considered to be 100%. With 54% of chlorination reaction rate, 38.34 g (0.54 mol) of chlorine react with 62.5 g (1 mol) of vinyl chloride resin, and 81.13 g of chlorinated vinyl chloride resin and hydrogen chloride 19 .71g means to generate. The chlorination reaction rate is calculated by measuring the weight of hydrogen chloride generated during the chlorination reaction and based on the weight of hydrogen chloride and the weight of the vinyl chloride resin used for the chlorination reaction. The hydrogen chloride generated during the chlorination reaction is absorbed in a predetermined amount of water, and the hydrogen chloride concentration in the aqueous solution is measured with an electric conductivity meter, and during the chlorination reaction based on the hydrogen chloride concentration and the weight of water The weight of generated hydrogen chloride can be calculated.

  In the present invention, the average particle diameter of the vinyl chloride resin powder when the chlorination reaction is carried out in the powder state of the vinyl chloride resin is not particularly limited, but those having a particle diameter range of 50 μm to 500 μm The particle diameter range is preferably 50 μm or more and 200 μm or less, and more preferably 100 μm or more and 200 μm or less. In the present invention, the average particle size of the vinyl chloride resin is measured in accordance with JIS K 0069.

  In the present invention, the method of adding the carbonic acid compound and the polycarboxylic acid salt to the chlorinated vinyl chloride resin is not particularly limited. For example, any one or more of the carbonic acid compound and the hydroxypolycarboxylic acid salt may be used as a solvent. After dissolving, it may be mixed with a chlorinated vinyl chloride resin powder, and any one or more of carbonic acid compounds and hydroxypolycarboxylic acid salts may be mixed with the chlorinated vinyl chloride resin powder as it is. As the solvent, for example, water or the like can be used. One or more of each of the carbonic acid compound and the hydroxypolycarboxylate may be dissolved in a solvent, and the whole solution may be mixed with the chlorinated vinyl chloride resin powder. When the compound is dissolved in a liquid and used, the carbonic acid compound and the hydroxypolycarboxylate preferably have an average particle size of 1 μm to 1000 μm both inclusive. When the average particle diameter is 1 μm or more, the aggregation of the powder and the adhesion to the wall surface and the like are small, and when it is 1000 μm or less, it can be easily dissolved in the liquid. In order that handling at the time of dissolving is easy, as for a carbonic acid system compound and a hydroxy polycarboxylic acid salt, it is more preferable that all are an average particle diameter of 100 micrometers or more and 1000 micrometers or less. Alternatively, the carbonic acid compound and the polycarboxylic acid salt may be added to the chlorinated vinyl chloride resin in the form of powder and mixed. When the powder is introduced as it is, it is preferable that the particle size be uniform and small in order to handle it easily and uniformly. Specifically, when the powder is introduced as it is, it is preferable that the carbonic acid-based compound and the hydroxypolycarboxylic acid salt each have an average particle diameter of 1 μm to 100 μm. In the present application, the “average particle size” of the carbonic acid compound and hydroxypolycarboxylate is measured in accordance with JIS Z 2510.

  The method of mixing the carbonic acid compound and the hydroxypolycarboxylate with the chlorinated vinyl chloride resin powder is not particularly limited, and may be, for example, manual mixing, and it may be used to mix the powder in a ball mill or generally. The device used may be used. Specifically, container rotation type devices such as horizontal cylindrical type, V type, double conical type, swing rotary type, etc., single axis ribbon type, double axis paddle type, rotary wedge type, twin axis planetary stirring type, cone It is preferable to use a mechanical stirring type device such as a screw type. The specific form of these devices is described in the Chemical Engineering Manual (edited by the Chemical Engineering Society, 6th revised edition, page 876).

  In the present invention, the order of addition when mixing the carbonic acid compound and the hydroxypolycarboxylate with the chlorinated vinyl chloride resin powder is not particularly limited. For example, a carbonated compound and a hydroxypolycarboxylate may be simultaneously added to a chlorinated vinyl chloride resin powder, or a carbonated compound and a chlorinated vinyl chloride resin powder may be added to the chlorinated vinyl chloride resin powder. After mixing one of the bodies, the other may be mixed.

  In the present invention, when mixing a carbonic acid compound or a hydroxypolycarboxylate dissolved in a solvent such as water with a chlorinated vinyl chloride resin powder, the chlorinated vinyl chloride resin powder is dried after mixing. Is preferred. It does not specifically limit about the method to dry, For example, ventilation drying, vacuum drying, etc. are mentioned.

  In the present invention, removal of chlorine and hydrogen chloride using other methods in combination is not limited. Other methods include, for example, air flow cleaning in which a chlorinated vinyl chloride resin is stirred or a fluidized bed is formed in a container in which a gas such as nitrogen, air, argon or carbon dioxide is circulated, or chlorinated vinyl chloride The vacuum degassing method etc. which vacuum-degas the container containing system resin and remove a chlorine and hydrogen chloride, etc. are mentioned.

  In the present invention, the static thermal stability of the chlorinated vinyl chloride resin is evaluated by using a sample (sheet) prepared using the chlorinated vinyl chloride resin and heating in an oven at 200 ° C. to make the sheet black. By measuring the time to Static thermal stability is higher as the time to blackening is longer. Specifically, 60 minutes or more are preferable, 70 minutes or more are more preferable, and 80 minutes or more are more preferable. In addition, the detail of evaluation of the static thermal stability of chlorinated vinyl chloride-type resin is mentioned later.

  EXAMPLES The present invention will be described more specifically by the following Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1
(Chlorination reaction process by gas-solid contact method)
The reactor shown in FIGS. 1 and 2 was used. In the present embodiment, a UV-LED light source manufactured by Sentech Co., Ltd., OX-221) was installed outside the fluidized bed reactor 17 as the ultraviolet irradiation device 22. First, 400 g of the vinyl chloride resin 102 having a degree of polymerization of 1000 was charged into the fluidized bed reactor 17. The filled vinyl chloride resin is obtained by a suspension polymerization method, and the average particle diameter measured by JIS-K0069 is 150 μm. The wet bottle 16 was charged with 0.5 L of pure water, and the temperature of the wet bottle 16 was adjusted to 30 ° C. Next, the flow control valve 13 was adjusted, and nitrogen gas was made to flow from the nitrogen cylinder 11 into the fluidized bed reactor 17 so that the display of the flow meter 14 became 1000 mL / min, and it was circulated as it was for 30 minutes. Thereafter, 100 vol% of chlorine gas was flowed from the chlorine cylinder 12 to the fluid bed reactor 17 by adjusting the flow control valve 13 so that the display of the flow meter 14 became 26000 mL / min. After 30 minutes, the vinyl chloride resin is irradiated with ultraviolet light using a UV-LED light source 22 (manufactured by Sentech Co., Ltd., OX-221) placed at a distance of 20 cm from the fluidized bed reactor 17 to perform chlorination reaction Started. During the chlorination reaction, the vinyl chloride resin was adjusted to a temperature of 70 ° C., and when the chlorine conversion reached 54%, the UV light source was turned off to terminate the chlorination reaction. After completion of the chlorination reaction, the chlorine gas flow was stopped, and nitrogen gas was flowed at a flow rate of 1000 mL / min for 30 minutes to replace chlorine in the reactor.

(Hydrogen chloride removal process)
Add 50 g of sodium tartrate dihydrate (average particle size 150 μm) as a hydroxypolycarboxylate and 0.25 g of sodium hydrogen carbonate (average particle size 77 μm) as a carbonate compound in a 50 mL volumetric flask so that it reaches 50 mL Pure water was added and allowed to stand at 25 ° C. for 24 hours to prepare an aqueous solution. To 100 g of the chlorinated vinyl chloride resin obtained by the chlorination reaction, 4 mL of the prepared aqueous solution was added, and stirred with a spatula so that the aqueous solution became uniform for 1 minute. Thereafter, the chlorinated vinyl chloride resin treated with the aqueous solution was again supplied to the fluidized bed reactor 17 and fluidized and dried in air at 30 ° C. for 1 hour. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.02 parts by weight of sodium tartrate dihydrate and 0.02 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Example 2)
A chlorinated vinyl chloride system was prepared in the same manner as in Example 1 except that 0.25 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 1.875 g of sodium hydrogen carbonate as the carbonic acid compound were used in the method of preparing the aqueous solution. I got a resin. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.02 parts by weight of sodium tartrate dihydrate and 0.15 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Example 3)
A chlorinated vinyl chloride system was prepared in the same manner as in Example 1 except that 1.875 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.25 g of sodium hydrogen carbonate as the carbonic acid compound were used in the method of preparing the aqueous solution. I got a resin. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.15 parts by weight of sodium tartrate dihydrate and 0.02 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Example 4)
In the same manner as in Example 1 except that 1.875 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 1.875 g of sodium hydrogen carbonate as the carbonic acid compound were used in the preparation method of the aqueous solution, in the same manner as in Example 1. I got a resin. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.15 parts by weight of sodium tartrate dihydrate and 0.15 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Example 5)
A chlorinated vinyl chloride system was prepared in the same manner as in Example 1 except that 0.625 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.625 g of sodium carbonate as the carbonate compound were used in the method of preparing the aqueous solution. I got a resin. As a result, a chlorinated vinyl chloride resin was obtained in which 0.05 parts by weight of sodium tartrate dihydrate and 0.05 parts by weight of sodium carbonate were added to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 1)
Chlorinated vinyl chloride was prepared in the same manner as in Example 1 except that 0.0625 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 3.125 g of sodium hydrogencarbonate as the carbonate compound were used in the method of preparing the aqueous solution. System resin was obtained. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.005 parts by weight of sodium tartrate dihydrate and 0.25 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 2)
In the same manner as in Example 1 except that 0.0625 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 1.875 g of sodium hydrogencarbonate as the carbonic acid compound were used in the preparation method of the aqueous solution in the same manner as in Example 1. I got a resin. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.005 parts by weight of sodium tartrate dihydrate and 0.15 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 3)
Chlorinated vinyl chloride was prepared in the same manner as in Example 1 except that 0.0625 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.25 g of sodium hydrogencarbonate as the carbonic acid compound were used in the method of preparing the aqueous solution. System resin was obtained. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.005 parts by weight of sodium tartrate dihydrate and 0.02 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 4)
Chlorinated vinyl chloride was prepared in the same manner as in Example 1 except that 0.25 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.0625 g of sodium hydrogencarbonate as the carbonic acid compound were used in the method of preparing the aqueous solution. System resin was obtained. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.02 parts by weight of sodium tartrate dihydrate and 0.005 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 5)
In the same manner as in Example 1, except that 1.875 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.0625 g of sodium hydrogencarbonate as the carbonic acid compound were used in the preparation method of the aqueous solution. A vinyl resin was obtained. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.15 parts by weight of sodium tartrate dihydrate and 0.005 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 6)
Chlorinated vinyl chloride was prepared in the same manner as in Example 1 except that 3.125 g of sodium tartrate dihydrate as the hydroxypolycarboxylate and 0.0625 g of sodium hydrogencarbonate as the carbonate compound were used in the method of preparing the aqueous solution. System resin was obtained. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.25 parts by weight of sodium tartrate dihydrate and 0.005 parts by weight of sodium hydrogen carbonate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 7)
A chlorinated vinyl chloride resin was obtained in the same manner as in Example 1 except that 0.625 g of sodium tartrate dihydrate was used as the hydroxypolycarboxylate and no carbonic acid compound was used in the method of preparing the aqueous solution. As a result, a chlorinated vinyl chloride resin was obtained by adding 0.05 parts by weight of sodium tartrate dihydrate to 100 parts by weight of the chlorinated vinyl chloride resin.

(Comparative example 8)
A chlorinated vinyl chloride resin was obtained in the same manner as in Example 1 except that the hydrogen chloride removing step was not performed.

  The corrosion rate and static thermal stability were measured and evaluated as follows using the chlorinated vinyl chloride resins obtained in Examples 1 to 5 and Comparative Examples 1 to 8. The results are shown in Table 1. Although the addition amount of a carbonic acid type compound and a hydroxy polycarboxylic acid salt is also shown in Table 1, the addition amount (part by weight) is a value when the chlorinated vinyl chloride resin is 100 parts by weight.

(Method of measuring corrosion rate)
The experimental apparatus shown in FIG. 3 was used. First, a pipe made of SUS304 with a diameter of 10 mm, a thickness of 1 mm and a length of 3 cm was prepared, and the initial weight was measured. Next, as shown in FIG. 3, 50 g of the chlorinated vinyl chloride resin 204 was placed in a 200 mL Teflon (registered trademark) container 201, 1 g of pure water was added to the sample, and mixed with a spatula for 1 minute. After mixing, place the cup 203 made of polypropylene on the chlorinated vinyl chloride resin 204, let the pipe 202 made of SUS304 whose weight is measured stand still in the cup 203, and cover the container 201 made of Teflon (registered trademark). It was closed and allowed to stand in a shelf dryer at 70 ° C. for 24 hours. After 24 hours, the pipe 202 made of SUS304 was taken out of the container 201 made of Teflon (registered trademark), and after standing for 2 hours in a shelf dryer at 70 ° C., the weight of the pipe 202 made of SUS304 after corrosion was measured again. . The corrosion rate (% by weight / day) was calculated by the following equation (1).

(Method of measuring static thermal stability)
10 parts by weight of methyl methacrylate butadiene styrene (MBS) resin, 2 parts by weight of a tin stabilizer, and 1.3 parts by weight of a lubricant based on 100 parts by weight of a chlorinated vinyl chloride resin, It knead | mixed for 5 minutes at 190 degreeC with a roll, and produced the 0.6-mm-thick sheet | seat. The obtained sheet was cut into a length of 3 cm and a width of 3.5 cm, heated in an oven at 200 ° C., and the time until the sheet was visually blackened was measured to evaluate static thermal stability.

  As can be seen from the results in Table 1, in Examples 1 to 5, good chlorinated vinyl chloride resins having a low corrosion rate and high static thermal stability can be obtained as compared with Comparative Examples 1 to 8. The From Comparative Examples 1 to 3, even if a predetermined amount of the carbonic acid compound is contained, when the amount of hydroxypolycarboxylic acid is small, the static thermal stability is deteriorated, and from Comparative Examples 4 to 7, the amount of hydroxypolycarboxylic acid is small. It was found that the corrosion rate is faster if the amount of carbonic acid compound is small, even if it is contained quantitatively. Further, according to Comparative Example 8, it was found that the corrosion rate became faster when the carbonic acid compound was not contained.

11 Nitrogen cylinder 12 Chlorine cylinder 13 Flow control valve 14 Flow meter 15 Water bottle 16 for moisture bottle temperature adjustment Wet container 17 Fluid bed type reactor 18 Fluid bed jacket 19 Hydrogen chloride absorption container 20 Chlorine absorption container 22 UV irradiation device (UV- LED light source)
DESCRIPTION OF SYMBOLS 101 Glass sinter for gas dispersion 102 Vinyl chloride resin 103 Gas inlet 104 Gas outlet 105 Ultraviolet transmission wall 106 Hot water 107 Thermocouple 108 Heat transfer tube 201 Teflon (registered trademark) container 202 Pipe made of 304 SUS 203 Polypropylene cup 204 Chlorinated vinyl chloride resin

Claims (7)

And adding a hydroxypolycarboxylate and at least one carbonated compound selected from the group consisting of carbonates and hydrogencarbonates to a chlorinated vinyl chloride resin.
When the chlorinated vinyl chloride resin is 100 parts by weight, the addition amount of the carbonic acid compound is 0.015 parts by weight or more and 0.2 parts by weight or less, and the addition amount of the hydroxypolycarboxylate is 0. It is characterized in that it is 015 parts by weight or more and 0.2 parts by weight or less, and the total addition amount of the carbonic acid compound and the hydroxypolycarboxylate is 0.03 parts by weight or more and 0.3 parts by weight or less. Method for producing chlorinated vinyl chloride resin.   The carbonic acid compound is a hydrogen carbonate, and when the chlorinated vinyl chloride resin is 100 parts by weight, the amount of the hydrogen carbonate added is 0.015 parts by weight or more and 0.2 parts by weight or less. The manufacturing method of the chlorinated vinyl chloride-type resin as described in 1.   The carbonate compound is a carbonate, and when the chlorinated vinyl chloride resin is 100 parts by weight, the addition amount of the carbonate is 0.015 parts by weight or more and 0.1 parts by weight or less. The manufacturing method of the chlorinated vinyl chloride-type resin of description.   The chlorinated vinyl chloride resin according to any one of claims 1 to 3, wherein the chlorinated vinyl chloride resin is a chlorinated vinyl chloride resin obtained by performing a chlorination reaction by bringing chlorine gas into contact with a powder of the vinyl chloride resin. The manufacturing method of the chlorinated vinyl chloride-type resin as described in a term.   The carbonic acid-based compound is at least one selected from the group consisting of alkali metal carbonates, alkali metal bicarbonates, alkaline earth metal carbonates and alkaline earth metal bicarbonates. The manufacturing method of the chlorinated vinyl chloride-type resin of any one of 4.   The method for producing a chlorinated vinyl chloride resin according to any one of claims 1 to 5, wherein the hydroxypolycarboxylate is sodium tartrate.   The method for producing a chlorinated vinyl chloride resin according to any one of claims 1, 2 and 4 to 6, wherein the carbonic acid compound is sodium hydrogen carbonate.

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