KR20080051279A - Method for preparing paste vinylchloride resin - Google Patents

Abstract

A method for preparing a paste vinyl chloride resin is provided to allow control of the particle diameter of a vinyl chloride resin in a spray drying step while avoiding a need for a separate pulverization step, to ensure low viscosity of the paste, and to obtain a matte sheet for wall paper and plastisol having excellent processability. A method for preparing a paste vinyl chloride resin comprises a step of carrying out spray drying of a vinyl chloride resin latex by using a spray drier, wherein the sprayer provided in the spray drier is controlled to a rotation speed of 9,000-141,000 rpm so that the spray dried vinyl chloride resin particles have a controlled average particle diameter of greater than 40 micrometers and equal to or less than 150 micrometers.

Description

Manufacturing method of paste vinyl chloride-based resin {METHOD FOR PREPARING PASTE VINYLCHLORIDE RESIN}

The present invention relates to a method for producing a paste vinyl chloride-based resin, and more particularly, by adjusting the average particle diameter of the paste vinyl chloride-based resin in the spray drying step without grinding, it has a low viscosity characteristics when applied to the plastisol The present invention relates to a method for preparing a paste vinyl chloride-based resin which ensures excellent workability and improves matt characteristics when applied to a wallpaper sheet.

Vinyl chloride-based resins are the most widely used general-purpose resins worldwide for living and industrial materials, and among them, paste-vinyl chloride-based resins are resins in the form of spherical particles having an average particle diameter of about 0.1 to 6 µm.

Paste vinyl chloride-based resin is usually prepared by the emulsion polymerization of a one-value particle latex, which is made of a resin in the form of a powder by the spray drying method to produce a final particle having an average particle diameter of 5 ㎛ or more, depending on the purpose It may also go through a grinding process.

Paste vinyl chloride-based resin prepared as described above is dispersed in a solvent or a plasticizer, such as reverse-roll coating, knife coating, screen coating, screen coating, gravure, It is applied to products such as flooring, wallpaper, tarpaulin, raincoats or gloves through processes such as screen printing, rotation casting or dipping.

In addition, the paste vinyl chloride resin is made of a special type of liquid mixture, such as plastisol or organosol, together with various additives such as conventional plasticizers and heat stabilizers, and is processed and molded to coat sheets such as wallpaper and flooring materials. In this case, the flow characteristics of the plastisol are important in the proper working period, and the viscosity of the plastisol has been recognized as a very important problem.

As a method for controlling the viscosity of the plastisol, there is a method of controlling the particle morphology by controlling the spray drying conditions of the paste vinyl chloride-based resin to control the size, porosity and hardness of the secondary particles. In general, the paste vinyl chloride-based resin is prepared by drying the latex, which is the emulsion-polymerized primary particles, by spray-drying, to produce a resin in the form of powder, which is the secondary particles. Although not present, the morphology of the paste vinyl chloride-based resin is usually controlled by controlling the temperature of the dryer inlet and the outlet. However, in this method, particles having an average particle diameter of 40 μm are mainly manufactured, and when applied to the plastisol, a pulverization step is required, and the plastisol has a problem of high viscosity. That is, only the temperature control of the spray dryer had a limitation in controlling the average particle diameter of the paste vinyl chloride resin.

In order to solve the problems of the prior art as described above, the present invention by controlling the average particle diameter of the vinyl chloride resin paste in the spray drying step without going through the grinding process, to ensure a low viscosity characteristics when applied to the plastisol excellent workability In addition, an object of the present invention is to provide a method for preparing a paste vinyl chloride-based resin for improving a matte property when applied to a wallpaper sheet.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention is a method for spray-drying a vinyl chloride-based resin latex with a spray dryer, spray-dried vinyl chloride by adjusting the rotational speed of the injection device provided in the spray dryer to 9,000 to 141,000 rpm Provided is a method of producing a paste vinyl chloride-based resin, characterized in that the average particle diameter of the resin is greater than 40 µm and adjusted to 150 µm or less.

The present invention also provides a paste vinyl chloride-based resin prepared by the above method, and a plastisol containing the same.

In addition, the present invention provides a wallpaper sheet manufactured using the plastisol.

Hereinafter, the present invention will be described in detail.

The present inventors, while studying to ensure the low viscosity characteristics of the plastisol, in spray drying the paste vinyl chloride-based resin, by adjusting the rotational speed of the spray device provided in the spray dryer, the vinyl chloride injected into the spray dryer When controlling the droplet size of the resin latex, it was confirmed that the average particle diameter of the final paste vinyl chloride resin can be controlled by controlling the thermal history received by the vinyl chloride resin during the spray drying process. In addition, when the paste-vinyl chloride-based resin prepared as described above is applied to the plastisol, the average particle diameter is controlled, and the degree of hardness of the particles and the moisture content on the surface are also controlled, resulting in low viscosity characteristics of the plastisol. After confirming that it can be secured, the present invention has been completed.

The method of manufacturing a paste vinyl chloride-based resin of the present invention is a method of drying by spraying a vinyl chloride-based resin latex by adjusting the rotational speed of the injection device provided in the spray dryer to 9,000 to 141,000 rpm. That is, by controlling the rotational speed of the injector, the size of the droplets of the vinyl chloride-based resin latex injected into the spray dryer is greatly controlled, and the average particle diameter exceeds 40 μm by controlling the thermal history received by the latex during spray drying. It is a method of manufacturing the paste vinyl chloride resin which is 150 micrometers or less, Preferably it is 65-90 micrometers.

The vinyl chloride-based resin latex may be prepared by adding a vinyl chloride monomer alone or a mixture of monomers copolymerizable therewith, an emulsifier, and an oil-soluble polymerization initiator in an aqueous medium, homogenizing, and then microsuspending polymerization.

In addition, the vinyl chloride monomer alone or a mixture of monomers copolymerizable therewith may be prepared by adding an emulsifier and a water-soluble polymerization initiator in an aqueous medium, followed by emulsion polymerization or seed emulsion polymerization. In this case, the seed may be used by mixing one to three or more seeds having different average particle diameters in consideration of particle size distribution (PSD) of the final paste vinyl chloride resin.

Auxiliary dispersants such as higher alcohols and higher fatty acids may be further used according to necessity during the microsuspension polymerization, emulsion polymerization or seed emulsion polymerization.

Examples of the monomer copolymerizable with the vinyl chloride monomer include olefins such as ethylene, propylene, butene, and the like; Vinyl esters of carboxylic acids such as vinyl acetate, vinyl propionate and vinyl stearate; Vinyl ethers having alkyl groups such as methyl vinyl ether, ethyl vinyl ether, octyl vinyl ether, and lauryl vinyl ether; Vinylidene halides such as vinylidene chloride; Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, maleic anhydride and itaconic anhydride and acid anhydrides thereof; Unsaturated carboxylic acid esters such as methyl acrylate, ethyl acrylate, monomethyl maleate, dimethyl maleate, and butylbenzyl maleate; Aromatic vinyl compounds such as styrene, α-methyl styrene and divinyl benzene; Unsaturated nitriles such as acrylonitrile; Or crosslinkable monomers, such as diallyl phthalate, etc. can be used individually or in mixture of 2 or more types. The amount of the copolymerizable monomer is preferably at most 50 parts by weight of 100 parts by weight of the total monomers used to prepare the vinyl chloride resin latex. When the content is up to 50 parts by weight, the polymerization is stable and the final paste vinyl chloride resin has excellent dispersibility in the plasticizer, thereby improving the processability.

Alkyl sulfate may be used as the emulsifier. Anionic emulsifiers or nonionic emulsifiers are used for the purpose of providing mechanical stabilization of vinyl chloride-based resin latex and low viscosity characteristics of plastisols. It can be used individually or in mixture of 2 or more types.

As the anionic emulsifier, carboxylic acid, alkyl sulfonic acid, alkyl benzene sulfonic acid, sulfo succinic acid, α-olefin sulfonic acid or alkyl phosphoric acid may be used. The amount of the anionic emulsifier is preferably at most 1 part by weight based on 100 parts by weight of the total monomers used to prepare the vinyl chloride resin latex. If the content is at most 1 part by weight, the polymerization and mechanical stability of the latex have an excellent effect.

As the nonionic emulsifier, polyoxyethylene ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkenyl ether, polyoxyethylene derivative, glycerin fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid ester, silicone emulsifier and the like can be used. Can be. The amount of the nonionic emulsifier to be used is not particularly limited and is preferably at most 3 parts by weight based on 100 parts by weight of the total monomers used in the production of the vinyl chloride resin latex.

The emulsifier may be added in an aqueous medium before the polymerization reaction, may be continuously added to the aqueous medium during the polymerization reaction, may be added to the latex after the polymerization reaction is completed, it can be used in combination with the above method if necessary.

The auxiliary dispersant is used to maintain the stability of the polymerization and latex with the emulsifier, specifically, higher alcohols such as lauryl alcohol, mystic alcohol, stearyl alcohol, or lauric acid, myristic acid, partic acid, Higher fatty acids such as stearic acid and the like can be used.

As the oil-soluble polymerization initiator used in the microsuspension polymerization, peroxy dicarbonates such as diisopropyl peroxy dicarbonate; organic peroxide initiators such as peroxy esters such as t-butyl peroxy pivalate and t-butyl peroxy neodecanoate, or azo (azo) such as 2,2-azobisisobutyronitrile. ) Initiator or the like can be used alone or in combination.

As the water-soluble polymerization initiator used in the emulsion polymerization or seed emulsion polymerization, ammonium persulfate, potassium persulfate, sodium persulfate or hydrogen peroxide may be used, and sodium sulfite, sodium, ascorbic acid, etc. as necessary. Can be used together.

Vinyl chloride-based resin latex may be prepared by polymerizing the above components. At this time, the polymerization conversion rate is 80 to 98% by weight, and the unreacted monomers which are not polymerized can be removed.

Vinyl chloride-based resin latex prepared as described above is preferably an average particle diameter of 0.2 to 0.9 ㎛. When the average particle diameter is 0.2 to 0.9 m, the dispersibility with the plasticizer is good, and there is an effect suitable for processing the paste sol.

The prepared vinyl chloride resin latex may be spray dried with a spray dryer to prepare a final paste vinyl chloride resin.

The spray drying is preferably carried out by adjusting the rotational speed of the injection device provided in the spray dryer at a temperature of 150 to 200 ° C. of the dryer inlet to 9,000 to 141,000 rpm. When the rotational speed of the injector is 9,000 to 141,000 rpm, the average particle diameter of the final paste vinyl chloride-based resin is more than 40 µm and has an effect of adjusting to 150 µm or less, preferably 65 to 90 µm.

The prepared paste vinyl chloride-based resin in a powder state is more than 40 μm and preferably 150 μm or less, preferably 65 to 90 μm. If the average particle diameter is more than 40 ㎛ and less than 150 ㎛ gives a low viscosity characteristics when applied to the paste sol, there is an effect to improve the matte effect when applied to the wallpaper sheet.

The paste vinyl chloride-based resin preferably has a degree of polymerization (K-value) of 70 to 80. When the polymerization degree is 70 to 80, the mechanical properties such as tensile strength are excellent, and the product productivity is high, thereby reducing the manufacturing cost.

The plastisol of the present invention includes 100 parts by weight of the prepared vinyl chloride resin, 60 to 80 parts by weight of plasticizer, 40 to 100 parts by weight of calcium carbonate, and other additives.

The paste vinyl chloride-based resin may be used in combination with the vinyl chloride-based blend resin to improve the fluidity of the plastisol.

The vinyl chloride-based blend resin is prepared by dehydrating a slurry produced by suspension polymerization of a vinyl chloride monomer alone or a copolymerizable monomer with a centrifugal dehydrator and flow drying, and preferably having an average particle diameter of 10 to 100 μm. Do. The amount of the vinyl chloride blend resin used is preferably at most 50 parts by weight in 100 parts by weight of the paste vinyl chloride resin. When the content is up to 50 parts by weight, the dispersibility with the plasticizer is excellent, thereby improving the workability.

Sheet of the present invention is prepared using the prepared plastisol, it can be used for wallpaper. The wallpaper sheet can be prepared by coating the blended plastisol on the wallpaper paper with a thickness of 0.2 to 0.4 mm, and then heating it in an oven at 165 ° C. for 45 seconds.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but the following examples are merely for exemplifying the present invention, and it will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention. It is natural that such variations and modifications fall within the scope of the appended claims.

EXAMPLE

Example 1

<Production of Paste Vinyl Chloride Resin>

Suspension polymerization was carried out using a lauryl peroxide-based polymerization initiator in a separate reactor in a conventional manner to prepare a vinyl chloride seed having an average particle diameter of 0.4 to 0.6 μm and a content of the polymerization initiator of 1.7%.

100 parts by weight of a vinyl chloride monomer, 0.8 parts by weight of sodium lauryl sulfate as an anionic emulsifier, 3 to 5 parts by weight of the vinyl chloride seed prepared separately, and the like were subjected to microsuspension polymerization to give a vinyl chloride-based particle having an average particle diameter of 0.9 μm. Resin latex was prepared.

The final paste of the vinyl chloride resin was prepared by spraying the vinyl chloride resin latex prepared by adjusting the rotation speed of the injector to 9,000 rpm at an inlet temperature of 195 ° C. and an outlet temperature of 68 ° C. of the spray dryer.

The prepared resin had a polymerization degree (K-value) of 72 and an average particle diameter of 90 μm.

<Production of Plastisol>

100 parts by weight of the prepared vinyl chloride-based resin, 80 parts by weight of calcium carbonate, 2 parts by weight of blowing agent, 3 parts by weight of TiO ₂ , and dioctyl phthalate (DOP) and diisononyl phthalate as a plasticizer , DINP) 80 parts by weight, hydrocarbon-based 10 parts by weight, tin-based stabilizer 2 parts by weight was added and mixed for 15 minutes, degassing under reduced pressure for 10 minutes to prepare a plastisol.

<Manufacture of Sheet>

The prepared plastisol was coated on the wallpaper coated paper to a thickness of about 350 μm, and then heated in an oven at 165 ° C. for 45 seconds to prepare a sheet.

Example 2

The preparation was performed in the same manner as in Example 1, except that the rotation speed of the injection device was adjusted to 14,100 rpm in the preparation of the paste vinyl chloride-based resin in Example 1.

The average particle diameter of the prepared paste vinyl chloride resin was 65 μm.

Comparative Example 1

Except for adjusting the rotational speed of the injection device in manufacturing the paste vinyl chloride resin in Example 1 to 20,300 rpm was carried out in the same manner as in Example 1.

The average particle diameter of the prepared paste vinyl chloride-based resin was 40 μm.

[Test Example]

The polymerization degree, the viscosity of the plastisol, and the glossiness of the sheet of the paste vinyl chloride resins prepared in Examples 1 to 2 and Comparative Example 1 were measured by the following methods, and the results are shown in Table 1 below.

* Degree of polymerization (K-value)-measured according to ISO1628-2.

* Viscosity (Pa.S)-The viscosity at 25 ° C., shear rate 1.8 / s and 100 / s was measured using a Rheometer (Physica, Z3).

Glossiness—Measured using a gloss measurement instrument that uses light scattering on the sheet surface.

division Example 1 Example 2 Comparative Example 1 Viscosity (Pa.S) 1.8 / s 10.18 15 18.38 100 / s 3.02 5.58 7.49 Glossiness 11 13 19

As shown in Table 1, the paste vinyl chloride resin of Examples 1 and 2 prepared by adjusting the rotational speed of the injection device provided in the spray dryer according to the present invention at 9,000 to 141,000 rpm when applied to the plastisol It was confirmed to impart low viscosity characteristics and lower the glossiness in the manufacture of the sheet.

On the other hand, the paste vinyl chloride-based resin of Comparative Example 1 prepared at the rotational speed of the conventional injector has a high viscosity because the average particle diameter is not controlled, and it was confirmed that the matte property was not excellent by increasing the glossiness when manufacturing the sheet. .

As described above, according to the present invention, it is possible to control the average particle diameter of the paste vinyl chloride-based resin in the spray drying step without going through the grinding process, and to secure a low viscosity characteristic by using the paste vinyl chloride-based resin having an average particle diameter controlled. By doing so, there is an effect of providing a plastisol excellent in processability and a wallpaper sheet having an improved matte property.

Claims (10)

A method of spray-drying a vinyl chloride-based resin latex with a spray dryer, the rotation speed of the spray device provided in the spray dryer to 9,000 to 141,000 rpm, so that the average particle diameter of the spray-dried vinyl chloride-based resin exceeds 40 ㎛ And characterized in that the adjustment to the range of 150 ㎛ or less Method for producing a paste vinyl chloride resin. The method of claim 1, The average particle diameter of the vinyl chloride-based resin is 65 to 90 ㎛, characterized in that Method for producing a paste vinyl chloride resin. The method of claim 1, The vinyl chloride-based resin latex is prepared by adding a vinyl chloride monomer alone or a mixture of monomers copolymerizable therewith, an emulsifier, and an oil-soluble polymerization initiator in an aqueous medium, homogenizing, and then suspending and polymerizing it. Method for producing a paste vinyl chloride resin. The method of claim 1, The vinyl chloride resin latex is prepared by adding a vinyl chloride monomer alone or a mixture of monomers copolymerizable therewith, an emulsifier, and a water-soluble polymerization initiator in an aqueous medium, followed by emulsion polymerization or seed emulsion polymerization. Method for producing a paste vinyl chloride resin. The method of claim 1, The vinyl chloride resin latex is characterized in that the average particle diameter is 0.2 to 0.9 ㎛ Method for producing a paste vinyl chloride resin. The method of claim 1, Inlet temperature of the spray dryer is characterized in that 150 to 200 ℃ Method for producing a paste vinyl chloride resin. The method of claim 1, The paste vinyl chloride-based resin, the degree of polymerization (K-value) is characterized in that 70 to 80 Method for producing a paste vinyl chloride resin. A paste vinyl chloride-based resin prepared by the process according to any one of claims 1 to 7, wherein the average particle diameter exceeds 40 µm and is 150 µm or less. The paste of claim 8, comprising 100 parts by weight of the vinyl chloride resin, 60 to 80 parts by weight of plasticizer and 40 to 100 parts by weight of calcium carbonate. Plastisol. A wallpaper sheet produced by coating the plastisol according to claim 9 on a wallpaper coated paper.