JP2003277566A - Polyvinyl alcohol-based resin composition and molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyvinyl alcohol-based resin composition producing a molding excellent in thermal fusibility/moldability, moisture resistance, disintegration in water, durability, strength, morphological stability or the like. <P>SOLUTION: The polyvinyl alcohol-based resin composition comprises (A) a thermofusible polyvinyl alcohol based resin with its main chain containing 1-14 mol% of ethylene, (B) a polyamide resin, and (C) an ethylene-unsaturated carboxylic acid copolymer or its metal salt, wherein (A)/(A+B+C)=0.5-0.99 (weight ratio) and (B)/(B+C)=0.02-0.98 (weight ratio). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyvinyl alcohol resin composition. More specifically, the present invention relates to a polyvinyl alcohol-based resin composition capable of producing a molded product excellent in hot melt moldability, water disintegration property, impact resistance, moisture resistance, durability, strength, shape stability and the like.

[0002]

Molded products obtained from polyvinyl alcohol have excellent water disintegration properties, mechanical properties, oil resistance, biodegradability, etc., and are used for agriculture, civil engineering, industrial use, medical use, packaging, leisure use. It is used in a wide range of fields such as, toys, sundries, daily necessities, containers and parts. However, polyvinyl alcohol has a drawback that it is inferior in impact resistance and flexibility, and there is a problem that, for example, when a molded product is dropped or bent, the molded product is easily broken. In order to solve this problem, various studies have been made so far, for example, a method of imparting impact resistance and flexibility by adding a plasticizer or an elastomer component has been studied. .

However, when a plasticizer is added to polyvinyl alcohol, not only the strength and elastic modulus of the obtained molded product may be greatly lowered or deformed when it is left under high humidity. However, the plasticizer may exude on the surface of the molded product, which is often a problem for its industrial use.

In general, elastomers represented by polyolefins and the like are originally incompatible with polyvinyl alcohol, do not disperse uniformly even when added, and have an effect of improving impact resistance and flexibility. In addition to being insufficient, there is a drawback that the transparency of the molded product is remarkably reduced, which is a problem particularly when the molded product is a film. In recent years, attempts have been made to improve compatibility by adding an elastomer having a functional group that reacts with a polyvinyl alcohol-based resin, but the reaction with the functional group causes a problem that the fluidity during molding is significantly reduced. Had. Also, plasticizer,
When additives such as surfactants, antifogging agents, and heat stabilizers are blended, the functional groups of these elastomers may react with each other to reduce the effects of each other, which may cause a problem. It was

Further, it has been investigated to impart impact resistance and flexibility by lowering the saponification degree of polyvinyl alcohol or copolymerizing it. However, in any method, it can be used from an industrial viewpoint. Not only it is not sufficient, but when the degree of saponification is lowered or copolymerization is carried out, when the obtained molded product is left under high humidity, the strength may be largely reduced or deformed in many cases. This has been a problem, and a resin composition capable of producing a molded product having impact resistance and flexibility while maintaining hot melt moldability, water disintegration property, shape stability, strength and the like has been desired.

[0006]

SUMMARY OF THE INVENTION Under such circumstances, the object of the present invention is to produce a molded product excellent in hot melt moldability, moisture resistance, water disintegration property, durability, strength and morphological stability. It is to provide a resin composition to be obtained.

[0007]

According to the present invention, the above object is to provide a heat-meltable polyvinyl alcohol resin (A) and a polyamide resin (B) containing ethylene in an amount of 1 to 14 mol% in the main chain. ), An ethylene-unsaturated carboxylic acid copolymer or a metal salt thereof (C), (A) / (A + B
+ C) = 0.5 to 0.99 (weight ratio), and (B) / (B + C) = 0.02 to 0.98 (weight ratio)
Can be achieved by the polyvinyl alcohol resin composition.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The polyvinyl alcohol resin (A) used in the present invention can be obtained by saponifying a copolymer of ethylene and vinyl ester. Here, a typical example of the vinyl ester is vinyl acetate, and in addition to this, vinyl propionate, vinyl pivalate, vinyl valerate, vinyl caprate,
Examples thereof include vinyl esters such as vinyl benzoate. These vinyl esters may be used either individually or in combination of two or more.

The polyvinyl alcohol resin (A) used in the present invention may be modified as long as the effects of the present invention are not impaired. Examples of vinyl monomers copolymerizable with vinyl ester include acrylamide and N.
-Methyl acrylamide, N-ethyl acrylamide,
Acrylamide monomers such as N, N-dimethylacrylamide; methacrylamide monomers such as methacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N, N-dimethylmethacrylamide; methyl vinyl ether, ethyl vinyl ether , N-propyl vinyl ether, i-propyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether, and other vinyl ether monomers, as well as α-olefins, allyl alcohol, vinyltrimethoxysilane, and N-vinyl-2.
-Pyrrolidone, isopropenyl alcohol, 7-octen-1-ol, allyl acetate, isopropenyl acetate and the like can be mentioned.

In the above polyvinyl alcohol resin (A), the content of ethylene is preferably 1 to 14 mol%, more preferably 2 to 13 mol%, and 3 to 12 mol%. Is particularly preferable. When the content of ethylene is less than 1 mol%, the effect of copolymerizing ethylene is not remarkable, and the heat melting property may decrease. On the other hand, when the ethylene content exceeds 14 mol%, the water disintegration property of the obtained molded product is deteriorated, which is not preferable.

The degree of polymerization of the polyvinyl alcohol resin (A) used in the present invention is appropriately selected depending on the use of the composition and the molded product, the required physical properties, the shape of the molded product, the molding method and the like. If it is low, the physical properties of the obtained molded article, especially impact resistance and mechanical properties, may deteriorate,
On the other hand, when the degree of polymerization is high, the melt viscosity becomes high, and the hot melt molding may become extremely difficult. Therefore, in consideration of the physical properties and melt moldability of the molded product, the polymerization degree of the polyvinyl alcohol-based resin is usually preferably in the range of 200 to 2000, and more preferably in the range of 250 to 1500.

The saponification degree of the polyvinyl alcohol resin (A) used in the present invention is appropriately selected depending on the use of the composition, the required physical properties and the molding method, and the use, the required physical properties and the shape of the molded product. If the degree is low, not only the water resistance, moisture resistance, and morphological stability of the resulting molded article will deteriorate, but also the thermal stability during molding may deteriorate, and an odor of acetic acid may be generated. When the degree is high, the water disintegration property of the molded article decreases. Considering these, the saponification degree of polyvinyl alcohol resin is usually 7
It is preferably in the range of 0 to 99.9 mol%, and particularly preferably in the range of 80 to 99.5 mol%.

The polyvinyl alcohol resin (A) used in the present invention needs to be heat-meltable. Here, the hot melt property means that molding conditions which do not cause deterioration such as remarkable deterioration and gelation during hot melt molding can be set, and a polyvinyl alcohol resin having a melting point of 170 to 230 ° C. is preferable. When the melting point is lower than 170 ° C., the thermal stability of the polyvinyl alcohol resin,
Water resistance, moisture resistance, and morphological stability decrease, which may cause problems. On the other hand, when the melting point exceeds 230 ° C., the temperature is close to the thermal decomposition temperature of the polyvinyl alcohol resin,
Molding may be difficult. Also, 190 ° C to 230
A material having a melt flow index of 0.1 to 500 g / 10 minutes under a load of 2160 g is generally used at any temperature in the range of ° C.

Further, polyvinyl alcohol resin (A)
May be used as a mixture of polyvinyl alcohol resins having different kinds and amounts of these comonomers, at least one of the degree of saponification, and the degree of polymerization.

The polyamide resin (B) used in the present invention is a polymer having an amide bond, and specific examples thereof include polycaproamide (nylon-6), polyundecane amide (nylon-11) and polylauryllactam. (Nylon-12), homopolymers such as polyhexamethylene adipamide (nylon-6,6), polyhexamethylene sebacamide (nylon-6,12), caprolactam / lauryllactam copolymer (nylon-6) / 1
2), caprolactam / aminoundecanoic acid polymer (nylon-6 / 11), caprolactam / ω-aminononanoic acid polymer (nylon-6,9), caprolactam / hexamethylene diammonium adipate copolymer (nylon-6 / 6) , 6), caprolactam / hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer (nylon-6 / 6,6 / 6,6)
12), an aromatic nylon, which is a polymer of adipic acid and metaxylylenediamine, or a polymer of hexamethylenediamine and m, p-phthalic acid. These polyamide resins may be used alone or in combination of two or more.

Among these polyamide resins (B), polyamides containing a nylon 6 component, such as nylon-6, nylon-6,12 and nylon-6 / 12, are used from the viewpoint of compatibility with polyvinyl alcohol resins. Polymers, nylon-6 / 6,6 copolymers and the like are preferable. When nylon has a high melting point, it is necessary to melt the composition at a high temperature when producing the composition or molding the composition, so that deterioration and gelation easily occur, and from the viewpoint of suppressing this,
The melting point of nylon is preferably 240 ° C. or lower,
Further, it is preferably 230 ° C. or lower. Further, the melt index (MI) of the polyamide resin (B) that can be preferably used in the present invention (210 ° C., 21
Under a load of 60 g) is 0.1 to 50 g / 10 min. And optimally 0.5 to 30 g / 10 min. Is. In the above, the MI when the melting point of the polyamide resin is around 210 ° C. or exceeds 210 ° C. is measured at a plurality of temperatures above the melting point under a load of 2160 g. Is plotted on the vertical axis,
The value is extrapolated to 210 ° C.

The ethylene-unsaturated carboxylic acid copolymer or its metal salt (C) used in the present invention means a polymer obtained by random copolymerization of ethylene and an unsaturated carboxylic acid, or a carboxylic acid component thereof. It is a metal salt (so-called ionomer) obtained by neutralization. Here, it is important that ethylene and the unsaturated carboxylic acid are randomly copolymerized, and the effect of the present invention cannot be achieved by graft-copolymerizing the unsaturated carboxylic acid with polyethylene. Although the reason is not clear, it is considered that the random copolymer is superior in compatibility with the polyamide resin (B) as compared with the graft copolymer. Among the components (C), a metal salt of an ethylene-unsaturated carboxylic acid copolymer can be preferably used from the viewpoint of the effect to be exerted. The reason why the metal salt is superior to the ethylene-unsaturated carboxylic acid random copolymer in terms of action and effect is not clear, but it is considered that the metal salt has better compatibility with nylon.

The content of unsaturated carboxylic acid is preferably 2 to 15 mol%, more preferably 3 to 12 mol%. As the unsaturated carboxylic acid, for example, acrylic acid,
Examples thereof include methacrylic acid, ethacrylic acid, maleic acid, monomethyl maleate, monoethyl maleate, and maleic anhydride, with acrylic acid or methacrylic acid being particularly preferred. Other monomers that may be contained in the copolymer include vinyl acetate, vinyl esters such as vinyl propionate, methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, and acrylic acid n. -Butyl, 2-ethylhexyl acrylate, methyl methacrylate, isobutyl methacrylate, unsaturated carboxylic acid esters such as diethyl maleate, carbon monoxide and the like are exemplified.

Examples of the metal ion in the ionomer include alkali metals such as lithium, sodium and potassium, and alkaline earth metals such as zinc, magnesium and calcium. Particularly, the use of zinc is preferable from the viewpoint of compatibility with nylon. . The degree of neutralization in the ionomer is preferably 100% or less, particularly 90% or less, and more preferably 70% or less. The lower limit of the degree of neutralization is usually 5% or more, preferably 10% or more, and more preferably 30% or more. The melt index (MI) of the ethylene-unsaturated carboxylic acid random copolymer or its metal salt that can be preferably used in the present invention (190 ° C, 2160).
g load) is 0.05 to 50 g / 10 minutes, more preferably 0.5 to 30 g / 10 minutes. These ethylene-unsaturated carboxylic acid random copolymers or metal salts thereof may be used alone or in combination of two or more.

The polyvinyl alcohol resin composition of the present invention has (A) / (A + B + C) = 0.5 to 0.99 (weight ratio), and (B) / (B + C) = 0.02.
It is necessary to be 0.98 (weight ratio). (A)
When / (A + B + C) is less than 0.5, the excellent properties originally possessed by the polyvinyl alcohol resin such as water disintegration property and biodegradability of the molded product obtained by melt-molding the composition are largely impaired. On the other hand, (A) / (A + B + C) is 0.
When it exceeds 99, the impact resistance and flexibility of the obtained molded article are deteriorated. (A) / (A + B + C) is 0.55 to 0.9
8 (weight ratio) is more preferable, and 0.6 to
It is particularly preferable that it is 0.97 (weight ratio).

If the ratio (B) / (B + C) is less than 0.02, the compatibility between the polyvinyl alcohol resin (A) and the polyamide resin (B) will decrease, probably because the polyvinyl alcohol resin (A) and the polyamide resin (B) are not compatible with each other. In addition to being unable to impart impact resistance,
The transparency of the obtained molded product may decrease. on the other hand,
If (B) / (B + C) exceeds 0.98, on the contrary, not only the impact resistance of the molded article deteriorates but also the thermal stability during molding deteriorates. The reason why the thermal stability deteriorates is not clear, but it is considered that the reaction between the polyvinyl alcohol resin and the polyamide resin adversely affects the melt stability. Considering impact resistance and thermal stability, (B) /
(B + C) is preferably 0.03 to 0.8 (weight ratio), more preferably 0.04 to 0.6 (weight ratio), and 0.05 to 0.5 (weight ratio). ) Is particularly preferable.

The polyvinyl alcohol resin composition of the present invention preferably further comprises 1 to 50 parts by weight of a solid plasticizer based on 100 parts by weight of the polyvinyl alcohol resin. The fluidity during molding can be further improved by adding a predetermined amount of the solid plasticizer. Here, the solid plasticizer is a substance that acts as a plasticizer for polyvinyl alcohol-based resin during melt molding and becomes solid when a molded product is used, specifically, a solid at 20 ° C., And it is a substance that becomes liquid at a temperature equal to or higher than the melting point of the polyvinyl alcohol-based resin and can improve the molding fluidity of the polyvinyl alcohol-based resin, and is preferably water-dispersible, and melt-kneaded with the polyvinyl alcohol. At this time, a substance having good dispersibility and compatibility is more preferable. Specific examples of such solid plasticizers include solid polyhydric alcohols, sorbitol, mannitol, pentaerythritol, dipentaerythritol and the like.

The polyvinyl alcohol resin composition of the present invention includes glycerin, diglycerin and their derivatives,
Known liquid plasticizers such as polyethylene glycol and water can be added. The liquid plasticizer can improve the molding fluidity and the flexibility of the molded product of the polyvinyl alcohol-based resin composition, but if the addition amount is too large, the water resistance or moisture resistance of the molded product is reduced, The plasticizer may exude on the surface of the molded product and cause a problem. From this viewpoint, the addition amount of the liquid plasticizer is preferably less than 20 parts by weight, and more preferably less than 15 parts by weight with respect to 100 parts by weight of the polyvinyl alcohol resin (A). Further, other additives (heat stabilizer, ultraviolet absorber, antioxidant, colorant, lubricant, release agent, filler, extender, surfactant, etc.) are added within a range not impairing the object of the present invention. You can also

Further, the polyvinyl alcohol resin composition used in the present invention and the molded product obtained by melt-molding the polyvinyl alcohol resin composition are within a range not impairing the object of the present invention.
Other thermoplastic resins such as water-disintegrating, biodegradable, and photodegradable biodegradable resins and general-purpose resins can be blended or laminated. There is no particular limitation on these thermoplastic resins, examples of biodegradable resins include polylactic acid, polyethylene succinate, polybutylene succinate, polycaprolactone, and the like, and general-purpose resins include polyethylene and polyolefins such as polypropylene. In addition, polystyrene, ABS resin, nylon, polyester resin and the like can be mentioned.

The method for producing the polyvinyl alcohol resin composition of the present invention is not particularly limited, and a method of melt-kneading the above-mentioned components is usually used. The melt-kneading of each component is carried out by, for example, (1) polyvinyl alcohol resin (A), polyamide resin (B), ethylene-unsaturated carboxylic acid copolymer or its metal salt (C) at the same time in a single screw or twin screw. A method of pelletizing with an extruder, etc. (2) First, a polyamide resin (B) and an ethylene-unsaturated carboxylic acid copolymer or a metal salt thereof (C) are melt-mixed, cooled, and then pelletized Can be dry-blended with the polyvinyl alcohol resin (A) and pelletized by a single-screw or twin-screw extruder. In particular, the above-mentioned (2), the polyamide resin (B) and the ethylene-unsaturated carboxylic acid copolymer or the metal salt thereof (C) are melt-blended first, and then the polyvinyl alcohol-based resin (A) and melt-blended. The method described above is preferable in terms of impact resistance of the molded product. Although the reason is not always clear, polyvinyl alcohol can be prepared by preparing a blend of a polyamide resin (B) acting as a compatibilizer and an ethylene-unsaturated carboxylic acid copolymer or a metal salt (C) thereof in advance. It is considered that the compatibility with the system resin (A) is improved and the resin composition comprising the three components forms a stable morphology.

A hot melt molding method can be used for producing a molded product using the polyvinyl alcohol resin composition of the present invention. There is no particular limitation on the shape and size of the molded product, and it can be appropriately selected depending on the application and purpose, such as lumps, plates, rods, boxes, cylinders, cylinders, bottles, containers, cups, sheets, caps, etc. Processed into a molded article. As the molding method at that time, various commonly used molding methods can be used, and examples thereof include an injection molding method, an extrusion molding method, a T-die extrusion molding method, an inflation molding method, a press molding method, and a hollow molding method. Method, a vacuum forming method, a pressure forming method, or the like, can be used.

The polyvinyl alcohol resin composition of the present invention can be effectively used for producing a laminated structure with other kinds of materials. Specific examples of other materials for laminating the polyvinyl alcohol-based resin composition of the present invention include high-density, medium-density or low-density polyethylene, vinyl acetate,
Acrylic ester, butene, polyethylene copolymerized with α-olefins such as hexene, ionomer resin, polypropylene homopolymer, ethylene, butene,
Preferred examples include polypropylene copolymerized with α-olefins such as hexene, polyolefins such as modified polypropylene blended with a rubber-based polymer, or thermoplastic resins obtained by adding or grafting maleic anhydride to these resins. be able to. Other thermoplastic resins that can be used include polyamide resins, polyester resins, polystyrene resins, polyvinyl chloride resins, acrylic resins, polyurethane resins,
Examples thereof include polycarbonate resin and polyvinyl acetate resin.

The polyvinyl alcohol resin composition of the present invention is excellent in hot melt moldability, various moldings can be produced by a desired molding method, and the moldings obtained have impact resistance. , Water disintegration, moisture resistance, durability, strength,
Due to its excellent morphological stability, it can be used in various fields of application such as agricultural, civil engineering, industrial, medical, packaging, leisure, toys, sundries, daily necessities, containers, parts and the like. Molded articles produced using the polyvinyl alcohol-based resin composition of the present invention have moldability, impact resistance,
It is possible to impart water disintegration without impairing morphological stability, has biodegradability, and has a low environmental load. Can be used for.

[0029]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. In the following Examples and Comparative Examples, "part" and "%" mean weight basis unless otherwise specified. In the following examples and comparative examples,
Polyvinyl alcohol is analyzed by J
It was performed according to IS-K6726. Moreover, as for the ethylene modification degree of the polyvinyl alcohol resin (A), a modified polyvinyl ester obtained by copolymerization of ethylene and vinyl acetate was used, and 500 MHz ¹ H-NMR (J
EOL GX-500) device was used to obtain the results.

In the following examples and comparative examples, the moldability when molding a molded product from the polyvinyl alcohol resin composition and the evaluation of the molded product obtained were carried out as follows. (1) The degree of resin filling of a molded product (launch fireworks stand) at the time of injection molding a fluid pellet was visually observed and evaluated according to the following criteria. ⊚: Completely filled at a molding temperature of 220 ° C. ◯: Some moldings were not filled at the molding temperature of 220 ° C, so when the molding temperature was set to 230 ° C, all moldings were completely filled. Δ: Some moldings were not filled at both molding temperatures of 220 ° C and 230 ° C. Poor: All moldings were unfilled at both molding temperatures of 220 ° C and 230 ° C. (2) Thermal stability The appearance of the obtained molded product (the launch fireworks stand) and the degree of deterioration of the resin during injection molding were visually observed and evaluated according to the following criteria. A: Almost no coloring or gel was observed in the molded product, and there was almost no smoke or decomposition odor due to deterioration of the resin. ◯: Coloring or gel is slightly observed on the molded product,
Alternatively, smoke or decomposition odor due to deterioration of the resin is slightly observed, but there is no practical problem. Δ: Deterioration of the resin is seen. X: The resin is significantly deteriorated and continuous molding is impossible. (3) Water disintegration The obtained molded product (launch fireworks stand) was immersed in water at 30 ° C for 28 days, and the degree of disintegration was visually observed. ⊚: Most of the molded products have collapsed and the shape has not been retained. ○: A small part of the molded product has collapsed, but the shape remains. X: Almost no disintegration of the molded product and very little swelling. Or it is not swollen at all. (4) Impact resistance Attach a polyethylene bag containing 4g of sand to a fireworks stand, glue a paper tube with a height of 20cm and a diameter of 35mmφ, and drop it on a concrete ground from a height of 2.5m. The change in appearance was visually observed and evaluated according to the following criteria. ⊚: The fireworks display has no cracks or fractures and no whitening. ◯: Cracks and whitening are observed in only a small part, but there is no breakage and there is no problem in practical use. X: The fireworks stand broke. (5) Morphological stability After leaving the fireworks stand at 20 ° C. and 65% RH for 28 days, the degree of deformation was visually observed and evaluated according to the following criteria. ⊚: No deformation is observed. ◯: Very slight deformation is observed, but there is no problem in practical use. X: It is considerably deformed.

Example 1 5 parts by weight of a nylon 6/12 copolymer (UBE nylon 7024B manufactured by Ube Industries, Ltd., hereinafter abbreviated as component (B)) and zinc neutralization with a methacrylic acid content of 7.5 mol%. 40 degrees
% Of ethylene-methacrylic acid copolymer (hereinafter abbreviated as component (C)) was dry-blended and then kneaded at a preset temperature of 215 ° C. using a twin-screw extruder to prepare pellets. Next, 80 parts by weight of ethylene-modified polyvinyl alcohol having a degree of polymerization of 450, a degree of saponification of 96.3 mol%, and a degree of ethylene modification of 8 mol% (hereinafter abbreviated as component (A)) was added to the pellets, and pentaerythritol 8 was used as a solid plasticizer. Parts by weight (10 parts / 100 parts of ethylene-modified polyvinyl alcohol) were added and pelletized again under the same conditions as above. The pellets thus obtained were injection-molded under the conditions of a cylinder temperature and a nozzle temperature of 220 ° C. and a mold temperature of 50 ° C., and a length of 5 cm and a width of 5 cm.
A fireworks stand with a box shape having a height of 1 cm and a wall thickness of 0.08 cm was prepared. Molding was carried out using a die having six shots in one shot. The moldability when molding a molded product from pellets and the evaluation of the molded product obtained were carried out by the methods described above. The evaluation results are shown in Table 2.

Examples 2 to 5 and Comparative Examples 1 to 5 Example 1 except that the mixing ratios of the components (A), (B), (C) and pentaerythritol were changed as shown in Table 1. In the same manner as above, a launch fireworks stand was prepared and evaluated. The evaluation results are shown in Table 2.

Examples 6 to 10 and Comparative Example 6 Same as Example 1 except that the degree of polymerization, the degree of saponification and the degree of ethylene modification of the ethylene-modified polyvinyl alcohol as the component (A) were changed as shown in Table 1. Then, a launch fireworks stand was prepared and evaluated. The evaluation results are shown in Table 2.

Example 11 A launch fireworks stand was prepared in the same manner as in Example 1 except that the components (A), (B), (C) and pentaerythritol were dry blended at once and pelletized simultaneously. And evaluated. The evaluation results are shown in Table 2.

Example 12 An example except that the pellets were prepared by dry blending the components (A), (B) and (C), and then pelletizing the pellets and pentaerythritol. In the same manner as in 1, a launch fireworks stand was prepared and evaluated. The evaluation results are shown in Table 2.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

EFFECT OF THE INVENTION The polyvinyl alcohol resin composition of the present invention is excellent in hot melt moldability, and it is possible to produce a molded product having an arbitrary shape and size by melt molding. The molded product thus obtained is
It has excellent impact resistance, water disintegration resistance, moisture resistance, durability, strength, and morphological stability, so it is used for agriculture, civil engineering, industrial use, medical use, packaging, leisure use, toys, sundries, daily necessities, containers. ,
It can be effectively used in various fields of application such as parts.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 23:08) F term (reference) 4F071 AA15 AA28 AA29 AA54 AA55 AA78 AF02 AF05 AF14 AF43 AF54 AH19 BA01 BB05 BC05 BC07 4J002 BB233 BE021 CH024 CL012 CL032 CL052 EC056 FD024 FD026

Claims (5)

[Claims] 1. A heat-meltable polyvinyl alcohol resin (A), a polyamide resin (B), an ethylene-unsaturated carboxylic acid copolymer or a metal thereof containing ethylene in an amount of 1 to 14 mol% in the main chain. Consisting of salt (C),
(A) / (A + B + C) = 0.5-0.99 (weight ratio), and (B) / (B + C) = 0.02-0.
A polyvinyl alcohol-based resin composition having a weight ratio of 98. 2. A polyvinyl alcohol resin (A) 10
The polyvinyl alcohol resin composition according to claim 1, wherein 1 to 50 parts by weight of the solid plasticizer is further added to 0 parts by weight. 3. A molded product obtained by melt-molding the polyvinyl alcohol resin composition according to claim 1. 4. The molded product according to claim 3, wherein the molded product is a stand for launch fireworks. 5. An ethylene-unsaturated carboxylic acid copolymer or its metal salt (C) and a polyamide resin (B) are melt-kneaded, and then the polyvinyl alcohol resin (A) is melt-mixed. Item 2. A method for producing the polyvinyl alcohol-based resin composition according to Item 1.