TW201231477A - Polyvinyl alcohol resin and manufacturing method thereof - Google Patents

Abstract

To provide a polyvinyl alcohol resin and a mamufacturing method of the same, in which the polyvinyl alcohol resin has excellent processing property and is hard to form a dissolved residue when it dissolved in water, and to provide a manufacturing method thereof. A polyvinyl alcohol resin slurry obtained through polymerization process (step S1) and saponification process (step S2) is heated to 100 to 170 DEG C, to make a volatile component contained therein not more than 1 mass % (step S3). Then, the resin, of which a volatile component has been removed, is extruded to have a strand configuration by using a mold having an opening with a diameter of 3 to 8mm. And the extruded resin is cooled to have a temperature 45 DEG C or less by air cooling or air blast cooling (step S4). Further, the cooled resin is pulverized to a rod shape particle having a length of 1 to 10mm, and a maximum diameter of 0.5 to 3.0mm.

Description

201231477 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a polyvinyl alcohol resin and a method of producing the same. More specifically, it relates to a polyvinyl alcohol resin which is used as a dispersing agent in the production of a gas-vinyl resin and a method for producing the same. [Prior Art] Polyvinyl alcohol (PVA) is a water-soluble synthetic resin and is used in various fields such as a film material, an emulsifying and dispersing agent, an adhesive, and a binder resin. This PVA resin is produced by polymerizing a vinyl acetate monomer and saponifying the obtained polyvinyl acetate. Usually, powder or granules are used (see Patent Documents 1 to 4). For example, in Patent Documents 1 and 2, in order to improve the dispersibility to water, the PVA particle diameter is made into PVA fine particles of several or less. On the other hand, in Patent Documents 3 and 4, a sheet-like or pellet-shaped pvA resin having a particle diameter of several hundred μη or more and even several mm or more is disclosed. In the method for producing a PVA resin pellet described in Patent Document 4, a water/alcohol mixed solution containing a PVA resin after a saponification process is extruded into a coagulating liquid having a solubility parameter δ of 9.3 to 14.4, by granulation. The strands of the machine, etc., are cut off to pelletize. ' [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ [ 4: Japan Special Open 2002 — 301715 f Hu Gazette [invention] 4/15

S 201231477 [Problems to be solved by the invention] The table S is as large as the offer], and the PV_micro-powder for the 2 records is easy to agglomerate when it is watery, and it is difficult to use it because of the volume Ask a little bit. The other side is a manufacturing method in which the pulverized portion of the technique for obtaining the sheet-like PVA resin is turned over and the other is agglomerated, and the resin is used in the liquid to be solidified. The obtained pellets are washed and the like. The manufacturing method described in Patent Document 4 is here. Therefore, the present invention provides a polyethylene resin which is useful for dissolving residues and a system for preparing the residue. Means of the subject] This is a bar-shaped particle having a length of 0.5 to 3.0 mm. ~A "In the present invention, since the polyvinyl alcohol resin is made into a child, no dust is generated, and the anti-caking property is improved, and the dissolution rate of water is increased faster. A method for producing a polyvinyl alcohol resin, which is obtained by saponifying polyethylene, heating the obtained solvent to just ~17 Gt, and volatilizing the contained into =, and the tree = poly liquid; 1~15mm hole mold, ',,, mass% after the resin is extruded into a strand-like process; _== 5/15 201231477 smashed and cooled tree ~3,0mm rod-shaped gas cooling or wind The process of cooling to a temperature of 45 ° C or lower; the grease 'receives a process having a length of 1 to 1 〇 rnm and a maximum diameter of 〇 5 particles. In the present invention, by using a coagulating liquid, it is melt-extruded & The polyethylene glycol resin is obtained, and a polyvinyl alcohol resin which is excellent in solubility in water and excellent in usability can be obtained. In the production method, when the volatile component is removed, the effect of the invention is also reduced. According to the present invention, since the polyvinyl alcohol resin is made into particles of a specific size, In addition, the solubility in water can also be improved. [Embodiment] [Formation for carrying out the invention] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Mosquito in the town, the fine polystyrene (PVA) resin is a rod-shaped particle, length = ~ l〇mm, the maximum diameter is 〜 5~3 〇 mm. Also, [shape]. ~', 匕 (10)-like PVA tree has a large surface area, which is dissolved in water; it is agglomerated, and it is difficult to dissolve in water, and because of the scattering of the specific gravity surface, the _ m is large in particle size. The pellet of the indefinite shape obtained by pulverizing the pf grease has a large degree of silkiness, and therefore has a large degree of silkiness, so that the pellets of the indefinite shape are in contact with each other due to pulverization = In the case where the piping «produces a tree or agglomerates, the usability is also poor. / 6/15

Sj 201231477 In contrast, the PVA resin of the present embodiment has a small surface area and a small contact area between particles; and = particles "caused to be agglomerated. Therefore, compared with the above-mentioned powder solution in water, the solubility in water is improved and the H & ^ large unbroken [length] The length of the PVA resin of the present embodiment is 丨~ "easy to produce knots The block 'is not easy to produce dissolved residue when dissolved in water: this is not when the PVA sealing particle length is less than linm, the ratio with respect to the wearing surface becomes lower, and it becomes easy to cause agglomeration. On the other hand, ^ hidden When the tree exceeds ―', it dissolves in water [maximum diameter] In this embodiment, the maximum diameter of the PVA resin is 〇5 to 3 〇 ugly. It is not easy to cause agglomeration, and it can suppress the dissolution residue when dissolved in water. In the case where the maximum diameter of the fm resin is less than G.5 mm, the pvA resin becomes glutinous, and the block, and the right is more than 3. Gmm, which causes dissolution residue in the water. Next, the manufacture of the PVA resin of the present embodiment will be described. The method is shown in Fig. 1. In the method for manufacturing the resin of the present embodiment, the polymerization process (step S1) and the saponification process are used. (Step S2), Desolvent Process (Step S3) Cooling Process ( Step S4) and the sequence of the pulverization process (step ss) [polymerization process] _ In the polymerization process of step S1, one or two or more kinds of ethylene vinegar are polymerized, or (10)! Copolymerization to obtain 7/15 201231477 polyethylene ester. The vinyl ester used herein may, for example, be ethyl formate, vinyl acetate, vinyl propionate, vinyl valerate, vinyl citrate or lauric acid. Ethylene vinegar, vinyl stearate, vinyl stearate, vinyl tridecyl acetate, vinyl versatate, etc., are particularly preferably vinyl acetate from the viewpoint of polymerization stability. The other monomer copolymerizable with these vinyl esters is not particularly limited, and examples thereof include α-olefins such as ethylene and propylene, methyl (meth)acrylate, ethyl (meth)acrylate, and (decyl)acrylic acid. Unsaturated decylamines such as butyl acrylate and alkyl (meth) acrylate such as alkyl (meth) acrylate, (meth) acrylamide and N-methylol acrylamide, (mercapto) acrylic acid, and croton Acid, maleic acid, itaconic acid and fumaric acid, etc. An unsaturated acid anhydride (sulfonyl group, ethyl group, propyl group, etc.) ester, an unsaturated acid anhydride such as maleic anhydride, a salt of an unsaturated acid (sodium salt, potassium salt, ammonium salt, etc.), a propylene group An epoxy group-containing test, a methacrylic acid epoxy, a monomer containing a glycidyl group, a sulfonic acid group-containing monomer such as a 2-propylene acrylamide-2-methylpropanesulfonic acid or a salt thereof, Isopropyl group-containing monomer, calcined ethylene _ etc., etc., such as methacrylic acid methacrylate (f) acid phosphopropyl propyl acrylate (acid ph〇sph〇x rush (7) methacrylate). In the purification process of step S2, the organic solvent is obtained in step S1 and saponified in the presence of a catalyst. Tow-曰 Use alcohols such as methanol, ethanol, and propanol 'ethylene glycol, propylene glycol, and propylene glycol, and particularly preferably methanol. In addition, the saponification catalyst can be exemplified by, for example, sodium hydroxide::rrr, phosphoric acid and hydrochloric acid. Among the catalysts, it is preferred to use a test catalyst, and it is preferable to use a gas oxidized nano. By this, 8/15 201231477 can speed up the saponification and increase productivity. By this saponification process, a part or all of the vinyl ester unit of the polyvinyl ester is saponified to form a vinyl alcohol unit. Further, the saponification degree of the PVA which is known by the saponification process described above can be appropriately set according to the route. [Desolvation Process] Next, the saponification solvent is removed from the PVA fine day slurry in the state of the saponification solvent obtained in the step S2, and the volatilization saponification (saponification > grain medium) contained in the pvA towel is set to 丨 mass%. The following (step magic). The specific method is not particularly limited, and a method of heating, decompressing, and decompressing liquid can be appropriately performed, for example, by using the press type machine or the like. Further, more than 1 mass remained in the pVA resin after the de-storage. In the pulverization process to be described later, the strands are less likely to be pulverized, or the portions other than the open portion are cut, and the shape of the obtained PVA resin varies. The heating temperature of the second and the second can be appropriately set according to the four-dissolved surface and can be = 2 rri7irc. 11 this, ^ points to remove the amount of volatile components, . (: When, the combination: 6 PVA resin turns yellow. Also, when the heating temperature is less than 100 170 [forming/cooling process] A is difficult to turn yellow. For 3~' to make _° have a plurality of diameter fats, to share Forming and squeezing; belt:: S3 is removed from the solvent by the eucalyptus on the machine, after being placed on the wheel conveyor, the temperature is reduced by the airborne or air-cooled load on the belt. Next (step S4). Thereby, a long rod-shaped tree gambling (stock) having a maximum diameter of 〇.5~9/15 201231477 3.0 mm is obtained. 丄: inverse:::::::=, ^ Pulling machine or pulverizer pulls, sometimes J (grinding process) Next 'use a pulverizer rod-like resin (strand) such as a granulator, so that the length becomes I~1Gmm = long shape S5) . At this time, the pulverization conditions are not special, and can be two-way, ^ _ knives of the knife, 卩 1 ~, / points of the shares (four) speed into the speed of 8 f pulls too fast 'because of the transfer to the stock The knives hit this = '1 rod-shaped particles become thicker, and become the cause of agglomeration, which will make the shape of the particle in the m2 resin, because the particle shape is 1~l〇mm, the maximum diameter 〇.5 ~3 〇mm rod shape, and the speed of the solution is '' and the anti-caking property is superior to the powdery products in the past, and it also produces dust. Further, the PVA resin of the present embodiment has a narrow particle size distribution and a uniform size. As a result, a PVa resin excellent in solubility in water and excellent in use of J. Due to this characteristic, the eucalyptus resin of the present embodiment is particularly suitable as a dispersing agent in the case of suspending a polymerization gas ethylene resin. [Examples] Hereinafter, examples and comparative examples of the present invention will be described, and the effects of the present invention will be specifically described. In the present embodiment, a plurality of PVA resin particles having different shapes and sizes were produced to evaluate their solubility and usability. Each of the P VA resin particles of the examples and the comparative examples was produced by the following method using the same p VA resin slurry. <PVA slurry> 10 parts by mass of vinyl acetate, 17 parts by mass of methanol, and relative to B

10/15 S 201231477 0.10% by mass of azobisisobutyronitrile of vinyl acetate was injected into the polymerization tank. Then, the inside of the tank was replaced with nitrogen, and the temperature was raised to the boiling point. Further, while adding a mixture of 3.5 parts by mass of vinyl acetate and 7.5 parts by mass of methanol to the polymerization rate of 75%, polymerization was carried out, and the polymerization rate was 90. Stop aggregation when %. Thereafter, the unpolymerized ethyl acetate was removed by a usual method to obtain a decyl alcohol solution of a polyethyl acetate (hereinafter referred to as PVAc) polymer. Next, a part of this solution was saponified by a usual method to obtain a PVA resin slurry having a viscosity average degree of polymerization: 400, a degree of saponification: 50 mol%, and a solid concentration of 45%. <PVA resin particles> (Example 1) The PVA resin slurry described above was dried under reduced pressure at 130 ° C, -〇.〇6 MPa, and then extruded through a die having a hole having a diameter of 3 mm. The strands were pulverized at a pulling speed of 20 m/min to obtain rod-shaped PVA resin particles having a length of 5 mm and a diameter of mm 5 mm. Further, the vacuum drying and pressure forming were carried out using a ruler rc kneading machine (manufactured by Kurimoto Iron Works Co., Ltd.). The same applies to the following examples and comparative examples. (Example 2) The PVA resin slurry described above was dried under reduced pressure at a temperature of 130 〇C, -〇.〇6 MPa, and then extruded through a die having a hole having a diameter of 5 mm, and the obtained strand was pulled at 20 m/min. The pulverization speed was measured to obtain rod-shaped PVA resin particles having a length of 5 mm and a diameter. (Example 3) The PVA resin slurry described above was salt-dried at 130 ° C, -〇.〇6 MPa, and then passed through a mold having a hole having a diameter of 8 mrn. The obtained strand was 20 m/min. The drawing speed was pulverized to obtain rod-shaped PVA resin particles having a length of 5 mm and a diameter of 坊3, 11/15, 201231477. (Example 4) The PVA resin slurry described above was dried under reduced pressure at 130 ° C and -0.06 MPa, and then extruded through a die having a hole having a diameter of 4 mm, and the obtained strand was pulled at a pulling speed of 5 m/min. The powder was pulverized to obtain rod-shaped PVA resin particles having a length Khnm and a diameter of 1.〇. (Example 5) The above-mentioned pVA resin slurry was dried under reduced pressure on the condition of i3〇t, -〇.〇6 MPa, and then extruded through a die having a hole having a diameter of 6 mm, and the obtained strand was pulled at 24 m/min. The pulverization speed was measured to obtain rod-shaped PVA resin particles having a length of 1 mm and a diameter of 1.〇. (Comparative Example 1) ^ The PVA resin slurry described above was dried under reduced pressure at 13 (TC, -0.06 MPa), and then extruded through a die having a hole having a diameter of 7 mm, and the obtained strand was pulled at 30 m/min. The powder was pulverized to obtain rod-shaped pVA resin particles having a length of 〇5 mm and a diameter of 1.0 mm. (Comparative Example 2) The PVA resin slurry described above was dried under reduced pressure of i3 (TC, -0_06 MPa), and then passed through a diameter of 3 mm. The die of the hole was extruded, and the obtained strand was pulverized at a pulling speed of 0.9 m/min to obtain rod-shaped pva resin particles having a length of 15 mm and a diameter of 1.0 mm. (Comparative Example 3) The above PVA resin slurry was 130. After drying under reduced pressure at ° C and -0.06 MPa, the film was extruded through a die having a hole having a diameter of 1 mm, and the obtained month was pulverized at a pulling speed of 20 m/ to obtain a rod-shaped PVA having a length of 5 mm and a diameter of 〇. Resin particles. 12/15

S 201231477 (Comparative Example 4) The PVA resin slurry described above was dried under reduced pressure at 130 ° C and -0.06 MPa, and then extruded through a die having a hole having a diameter of 9 mm to obtain a strand of 20 m/min. The pulverization speed was measured to obtain rod-shaped PVA resin particles having a length of 5 mm and a diameter of 3.5 mm. <Solubility> 5 parts by mass of the PVA resin particles of the examples or the comparative examples and 95 parts by mass of pure water at 23 ° C were placed in a 1 L liquid separation flask, and the mixture was stirred at a stirring speed of 200 rpm at a stirring speed of 200 rpm to measure PVA. The time from the resin to complete dissolution. Also, the measurement time is up to 60 minutes. <Useability> 5 parts by mass of the PVA resin particles of the examples or the comparative examples and the pure water of % Berry 23 C were placed in a 1 L liquid separation flask, and the mixture was passed through a seedling type, and the mixing speed was 200 rpm. The solution which was disturbed for 50 minutes was passed through a stainless steel tube having an inner diameter to confirm whether or not resin clogging occurred inside the tube. The above results are summarized in Table 1 below. [Table 1]

13/15 201231477 1 Comparative Example 2 ❼ PVA resin, the maximum diameter is more than 3.0 mm The PVA resin of Comparative Example 4 has good usability and dissolves the residue. And only a ratio of eight π j. Umm but generated when dissolved in water, the length, the maximum diameter, the maximum diameter and the particle size of the rod-shaped particles are all

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing a method of producing a PVA resin according to an embodiment of the present invention. [Main component symbol description] 〇

S

Claims (1)

201231477 VII. Patent application scope: 1. A polyvinyl alcohol resin which is a rod-shaped particle having a length of 1 to 10 mm and a maximum diameter of 0.5 to 3.0 mm. 2. A method for producing a polyvinyl alcohol resin, comprising: heating a polyvinyl alcohol resin slurry obtained by saponifying a polyvinyl ester to 100 to 170 ° C, and preparing the volatile component to be 1% by mass or less Using a mold having a hole having a diameter of 3 to 8 mm, the resin obtained by removing the volatile component is extruded into a strand-like process; and the resin after extrusion molding is air-cooled or air-cooled to a temperature of 45 ° C or lower. The process of pulverizing the cooled resin to obtain rod-shaped particles having a length of 1 to 10 mm and a maximum diameter of 0.5 to 3.0 mm. 3. The method for producing a polyvinyl alcohol resin according to the second aspect of the patent application, wherein the volatile component is removed while stirring under reduced pressure. 4. The method for producing a polyvinyl alcohol resin according to claim 2, wherein the resin obtained by removing the volatile component is extruded on a belt, and the formed resin is air-cooled or air-cooled on the belt. . 15/15