JP4704708B2 - Resin composition and method for producing the same - Google Patents

Description

  The present invention relates to a resin composition comprising a vinyl alcohol polymer and an inorganic compound, and a method for producing the same, which can provide a film having a good appearance even after restarting an extruder in film processing. About.

  In general, vinyl alcohol polymers such as saponified ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVOH) have transparency, antistatic properties, oil resistance, solvent resistance, gas barrier properties, and fragrance retention. It is an excellent thermoplastic resin that can be melt-molded, and is used for various packaging materials such as food packaging. For the purpose of further improving gas barrier properties, attempts have been made to blend inorganic substances into vinyl alcohol polymers.

For example, a method of melting and mixing EVOH having a water content of 25 to 50% by weight and a water-swellable layered inorganic compound (Patent Document 1), while melting and mixing EVOH having a water content of 50% by weight or less and a water-swellable layered inorganic compound , A method of removing moisture to reduce the water content in the resin composition to 5% by weight or less (Patent Document 2), EVOH having a water content of 40% by weight or less and a water-swellable layered inorganic compound aqueous dispersion are melt mixed. Method (Patent Document 3), EVOH having a water content of 0.5% by weight or more is introduced into an extruder, and an aqueous dispersion of inorganic fine particles is blended with the water-containing and molten EVOH in the extruder. The method (patent document 4) etc. to perform are known.
JP 2000-191874 A JP 2002-003611 A JP 2002-003613 A JP 2002-284887 A

  The resin composition obtained by each of the above methods can be processed into a film showing good oxygen barrier performance. However, when the resin compositions are processed into a film, when the extruder is temporarily stopped and restarted, there is a problem that the appearance of the film after the restart is deteriorated.

  As a result of intensive studies, the present inventors have produced a vinyl alcohol polymer having a water content of 70% by weight or less in producing a resin composition containing the vinyl alcohol polymer (A) and the inorganic compound (B). It has been found that the above-mentioned problem can be solved by removing moisture while kneading the combined (A) and inorganic compound (B) aqueous dispersion to make the water content in the resin composition 5% by weight or less, The present invention has been completed.

That is, the present invention is as follows.
[1] In producing a resin composition comprising a vinyl alcohol polymer (A) and an inorganic compound (B), a vinyl alcohol polymer (A) having a water content of 70% by weight or less and an inorganic compound ( B) A method for producing a resin composition, wherein moisture is removed while kneading the aqueous dispersion to reduce the water content in the resin composition to 5% by weight or less.
[2] The method for producing a resin composition as described in [1] above, wherein kneading is performed under the conditions satisfying the following formulas (1) to (3) simultaneously.

However, t represents the kneading time (seconds), T ₀ represents the resin temperature (° C.) at the start of kneading, and T ₁ represents the resin temperature (° C.) at the end of kneading.
[3] The method for producing a resin composition according to the above [1] or [2], wherein the solid content concentration of the inorganic compound (B) aqueous dispersion is 10% by weight or more.
[4] The process for producing a resin composition according to any one of [1] to [3], wherein the inorganic compound (B) is a layered inorganic compound.
[5] The method for producing a resin composition according to any one of [1] to [4], wherein the vinyl alcohol polymer (A) is a saponified ethylene-vinyl acetate copolymer.
[6] A resin composition obtained by the method for producing a resin composition according to any one of [1] to [5].

  The method for producing a resin composition of the present invention can provide a resin composition that provides a film having an excellent appearance even after restarting an extruder in film processing. The resin composition obtained by the production method is used for films, sheets, containers, etc., and is useful as various packaging materials such as general foods, retort foods, pharmaceuticals, industrial chemicals, and agricultural chemicals, and is laminated with various resins. It is also useful for containers such as gasoline tanks and agricultural chemical bottles.

The present invention is described in detail below.
The vinyl alcohol polymer (A) used in the present invention is not particularly limited, and is obtained by saponifying a vinyl ester polymer obtained by polymerizing a vinyl ester compound.
Examples of such vinyl ester compounds include vinyl formate, vinyl acetate, vinyl trifluoroacetate, vinyl propionate, vinyl butyrate, vinyl caprate, vinyl laurate, vinyl versatate, vinyl palmitate, vinyl stearate, etc. Although used in combination, vinyl acetate is preferred for practical use.
Specific examples of the vinyl alcohol polymer (A) include polyvinyl alcohol (hereinafter abbreviated as PVA).

  Although it does not specifically limit as PVA used for this invention, The saponification degree is 60 mol% or more (further 90 mol% or more), and the polymerization degree is 200-3500 (further 400-1000). If the saponification degree is less than 60 mol%, the gas barrier property may be insufficient, which is not preferable. On the other hand, if the degree of polymerization exceeds 3500, the load during melt processing is large, and the resin may be thermally deteriorated with the generation of shearing heat. If the degree of polymerization is less than 200, the mechanical properties of the molded product are lowered, which is not preferable.

  The vinyl alcohol polymer (A) may be copolymerized with other copolymerizable ethylenically unsaturated monomers other than vinyl ester compounds. Examples of such monomers include ethylene, Olefins such as propylene, 1-butene and isobutene, unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid, (anhydrous) phthalic acid, (anhydrous) maleic acid and (anhydrous) itaconic acid, or salts thereof, or carbon number 1 -18 mono- or dialkyl esters, acrylamide, C1-C18 N-alkyl acrylamide, N, N-dimethylacrylamide, 2-acrylamidopropanesulfonic acid or its salt, acrylamidopropyldimethylamine or its acid salt or its 4 Acrylamides such as grade salts, methacrylamide, N having 1 to 18 carbon atoms Alkylmethacrylamide, N, N-dimethylmethacrylamide, 2-methacrylamideamidopropanesulfonic acid or its salt, methacrylamide such as methacrylamideamidopropylamine or its acid salt or its quaternary salt, N-vinylpyrrolidone, N- N-vinylamides such as vinylformamide and N-vinylacetamide, vinyl cyanides such as acrylonitrile and methacrylonitrile, vinyl ethers such as alkyl vinyl ether having 1 to 18 carbon atoms, hydroxyalkyl vinyl ether and alkoxyalkyl vinyl ether, vinyl chloride, Vinyl halides such as vinylidene chloride, vinyl fluoride, vinylidene fluoride and vinyl bromide, vinyl silanes such as trimethoxyvinyl silane, allyl acetate, allyl chloride, allyl alcohol , Dimethylallyl alcohol, trimethyl- - (3-acrylamido-3-dimethylpropyl) - ammonium chloride, and the like acrylamido-2-methylpropanesulfonic acid. Further, it may be post-modified such as urethanization, acetalization, cyanoethylation, etc. within the range not impairing the gist of the present invention.

Of these, ethylene-modified saponified ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVOH) is excellent in terms of thermal stability.
Such EVOH is not particularly limited, but the ethylene content is preferably less than 60 mol% (more preferably less than 55 mol%, particularly less than 50 mol%). If the ethylene content is 60 mol% or more, the gas barrier property is lowered, which is not preferable. The lower limit of the ethylene content is not particularly limited, but is preferably 10 mol% or more (more preferably 15 mol% or more, particularly 20 mol% or more). When the ethylene content is less than 10 mol%, the water resistance and thermal stability are lowered, which is not preferable.

Moreover, the saponification degree of the vinyl acetate component of the EVOH is preferably 90 mol% or more (more preferably 95 mol% or more, particularly 99.5 mol% or more). If the degree of saponification is less than 90 mol%, the gas barrier property and heat resistance may be insufficient, which is not preferable.
Furthermore, the melt index (MI) of the EVOH is preferably 1 to 100 g / 10 min (210 ° C., load 2160 g), more preferably 2 to 50 g / 10 min. If the melt index (MI) is less than 1 g / 10 min, the load becomes too large during melt processing, which hinders processing. If the melt index (MI) exceeds 100 g / 10 min, the viscosity becomes too low during melting and dripping occurs. This is not preferable because it cannot be formed.

  In the present invention, in producing the target resin composition, the water content of the vinyl alcohol polymer (A) must be 70% by weight or less (more preferably 60% by weight or less, particularly 50% by weight or less). There is. If it exceeds 70% by weight, the resin viscosity at the time of kneading is too low and the kneading action is weak, so that the vinyl alcohol polymer (A) and the inorganic compound (B) cannot be uniformly kneaded. Further, the lower limit of the moisture content is not particularly limited, but is preferably 5% by weight or more (more preferably 10% by weight or more, particularly 15% by weight or more). When the water content is less than 5% by weight, it is necessary to set a high processing temperature at the start of kneading because water is insufficient, and the dispersibility of the inorganic compound (B) at the time of mixing tends to be insufficient. Absent.

The method for containing water in the vinyl alcohol polymer (A) is not particularly limited, but it is preferable that water is uniformly contained in the vinyl alcohol polymer (A). A method in which a solution of the polymer (A) is precipitated in water, washed thoroughly with water to remove the solvent and contain water, and a method in which the vinyl alcohol polymer (A) is treated in pressurized hot water for about 1 to 3 hours. In addition, known methods such as a method of precipitating a paste after saponification in water during production of the vinyl alcohol polymer (A) and containing water (for example, see JP-A-2002-003611). Among these, the method of precipitating the paste after saponification in water during the production of the vinyl alcohol polymer (A) is particularly preferably used.
In addition, after adjusting the water content by the above method and before melt-kneading with the inorganic compound (B) aqueous dispersion, a known drying treatment (hot air drying, dielectric heating drying, microwave irradiation drying, etc.) is performed as necessary. It is also preferable from the viewpoint of kneading stability to perform (re) adjustment of the water content by carrying out the above) or to perform the surface adhering water removal operation of the pellets in advance.

  The inorganic compound used in the present invention has a structure in which a large number of sheets (for example, a tetrahedral sheet of silicon oxide and an octahedral sheet of metal hydroxide) are laminated and swells in water and / or an organic solvent. In particular, a water-swellable layered inorganic compound having a property of swelling in water is preferable. The water-swellable layered inorganic compound is not particularly limited, and includes clay minerals such as smectite and vermiculite, and further synthetic mica. Specific examples of the former smectite include montmorillonite, beidellite, nontronite, saponite, Examples include hectorite, soconite, and stevensite. Further, water-swellable fluoromica-based minerals such as Na-type fluorine tetrasilicon mica, Na-type teniolite, Li-type teniolite, Na-type hectorite are also preferably used. These may be natural or synthesized. Moreover, you may use what was organically-treated with the organic cation represented by the quaternary ammonium salt.

  In the present invention, the degree of swelling of the water-swellable layered inorganic compound (measured according to the standard test method volume method of the Japan Bentonite Industry Association) is preferably larger, and the degree of swelling is 85 ml / 2 g or more (further 90 ml). / 2 g or more, particularly 95 ml / 2 g or more). If the degree of swelling is less than 85 ml / 2 g, the gas barrier properties are insufficient, which is not preferred. Considering the degree of swelling, montmorillonite is preferred as the water-swellable layered inorganic compound. The aspect ratio of the water-swellable layered inorganic compound is not particularly limited, but is preferably 100 or more.

  In the present invention, it is necessary to prepare the inorganic compound (B) as an aqueous dispersion in producing the desired resin composition. In order to obtain such an aqueous dispersion, it may be stirred using a known stirring device. In order to further improve the dispersibility, a high-pressure dispersing device such as an ultra-high pressure homogenizer, a ball mill, an ultrasonic treatment device, or the like can be used.

  The lower limit of the solid content concentration of the aqueous dispersion is not particularly limited, but is preferably 10% by weight or more (more preferably 30% by weight or more, particularly 50% by weight or more). If the solid content concentration is less than 10% by weight, the difference in viscosity from the resin is too large, and the viscosity of the resin is greatly reduced and the kneading action is weakened. Therefore, the vinyl alcohol polymer (A) and the inorganic compound (B) May not be uniformly kneaded, which is not preferable. Further, the upper limit of the solid content concentration of the aqueous dispersion is preferably 99% by weight or less (more preferably 90% by weight or less, particularly 75% by weight or less). When the solid content concentration exceeds 99% by weight, water is insufficient, the peelability of the inorganic compound (B) is poor, the dispersibility becomes insufficient, and the film appearance may be deteriorated.

  In the present invention, water is removed while kneading the vinyl alcohol polymer (A and inorganic compound (B) aqueous dispersion having a water content of 70% by weight or less as described above (that is, kneading and water removal). The maximum characteristic is that the water content in the obtained resin composition is 5% by weight or less.

  In the present invention, when the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the aqueous dispersion of the inorganic compound (B) are kneaded, the water content of the entire resin composition at the time of mixing is 10 to 80% by weight. % (More preferably 20 to 60% by weight, particularly 25 to 45% by weight). If the water content is less than 10% by weight, the dispersibility of the inorganic compound (B) becomes insufficient. Conversely, if the water content exceeds 80% by weight, the vinyl alcohol polymer (A) and the dispersion are in a non-uniform mixed state. It is not preferable.

  In addition, the blending ratio of the vinyl alcohol polymer (A) and the inorganic compound (B) to be kneaded is 100 parts by weight (solid content) of the vinyl alcohol polymer (A) with respect to the inorganic compound (B). 0.1 to 100 parts by weight (solid content) (further 0.1 to 50 parts by weight (same as the left), especially 0.5 to 20 parts by weight (same as the left), and particularly 1 to 7.5 parts by weight ( Same as on the left)). If the blending ratio is less than 0.1 parts by weight, the effect of improving the gas barrier property is small. Conversely, if it exceeds 100 parts by weight, the appearance of a molded article such as a film may be deteriorated, which is not preferable.

  In the present invention, first, the mixing (mixing) ratio of the target vinyl alcohol polymer (A) and the inorganic compound (B) is determined, and the water content of the entire resin composition at the time of mixing is taken into consideration. The water content of the alcohol polymer (A) and the solid content concentration of the inorganic compound (B) aqueous dispersion may be determined and used for kneading.

  Furthermore, in the present invention, when EVOH is used as the vinyl alcohol polymer (A) in kneading the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the inorganic compound (B) dispersion, It is also preferable to select EVOH so as to satisfy the condition of the formula (a). By adjusting the ethylene content, the saponification degree, and the water content of EVOH so as to satisfy the following formula (a), the extrudability with the dispersion and the gas barrier properties are improved.

  That is, when the value of the following formula (a) is less than 60, EVOH and the dispersion are in a non-uniform mixed state and gas barrier properties are deteriorated. Conversely, when it exceeds 120, extrusion processability is unfavorably deteriorated.

Et represents the ethylene content (mol%), Sv represents the degree of saponification (mol%), and W represents the water content (wt%).

  In kneading the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the aqueous dispersion of the inorganic compound (B), there are no particular limitations on the apparatus and method used. For example, an extruder, kneader, mixing roll In addition, a known method performed using a known kneading (mixing) apparatus such as a Banbury mixer, a plast mill, or a Brabender can be used. These kneading apparatuses may be used alone or in combination of two or more apparatuses. Moreover, the apparatus to be used may be appropriately selected depending on the types, properties, shapes, etc. of the vinyl alcohol polymer (A) and the inorganic compound (B). Usually, a twin-screw extruder or Banbury that is widely used industrially. A mixer, a kneader, a brabender or the like is preferably used. Furthermore, in the present invention, since it is necessary to remove moisture during kneading, those equipped with exhaust and / or drainage means such as a vent, a slit barrel, a drainage port, and a drainage pump are preferable.

  Although it does not specifically limit as a twin-screw extruder used for this invention, A thing with an internal diameter of 20 mm or more (further 30-150 mm) is preferable, and since this productivity is scarce if this internal diameter is less than 20 mm, L / D Is preferably 20 or more (more preferably 30 or more). When the L / D is less than 20, it is not preferable because the kneading time is short and it becomes difficult to remove the water content to 5% by weight or less.

  The shape of the die hole provided at the exit of the extruder is not limited, but it is an appropriate shape and size [in the case of a columnar shape, the diameter is 1 to 10 mm and the length is 1 to 10 mm (and each 2 to 6 mm In consideration of obtaining the resin composition pellets of 1)], a circular shape having a diameter of 1 to 7 mm (more preferably 2 to 5 mm) is preferable, and the number of holes is 3 to 100 (more preferably 10 to 50). The degree is preferable for production. Furthermore, it is also preferable to provide one or more mesh screens (especially two or more) between the extruder and the die entrance for removing foreign substances and stabilizing the resin pressure (extrusion stabilization). Furthermore, extrusion stability In view of the above, it is also preferable to provide a gear pump, a heat exchanger or the like.

  There are no particular restrictions on supplying the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the aqueous dispersion of the inorganic compound (B) to the twin-screw extruder. (1) Vinyl alcohol polymer (A ) And an inorganic compound (B) aqueous dispersion previously blended into the hopper of the extruder, (2) the vinyl alcohol polymer (A) and the inorganic compound (B) aqueous dispersion are directly extruded (3) The vinyl alcohol polymer (A) is supplied to the hopper of the extruder and the inorganic compound (B) aqueous dispersion is supplied from a part of the barrel of the extruder ( Side feed) method and the like. In carrying out the method (3), the aqueous dispersion can be supplied from the vent port using gravity or can be supplied under pressure.

  Thus, the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the aqueous dispersion of the inorganic compound (B) are supplied to a twin-screw extruder and kneaded. It must be removed from the machine vent. The extruder should have at least one vent, particularly preferably at least two, and at least one of the vents is preferably sucked under reduced pressure in terms of drying efficiency and the quality of the resulting resin. . In the case of the above (3), it is preferable that there are two or more vents, particularly three or more, and the inorganic compound (B) aqueous dispersion is supplied at a position closest to the hopper, It is preferable in view of drying efficiency and the quality of the obtained resin composition that at least one of the remaining portions is sucked under reduced pressure.

The kneading is not particularly limited, but the temperature of the cylinder at the hopper inlet of the extruder (T _IN ) and the temperature of the cylinder at the outlet of the extruder (T _OUT ) satisfy the following formula (b). When T _OUT / T _IN is less than 2, the drying ability may be insufficient or the extrusion may become unstable. Conversely, when T _OUT / T _IN is 8.5 or more, the resin composition The quality of the product may deteriorate (thermal deterioration) or the extrusion may become unstable, and it may not satisfy the following formula (b ′), particularly the following formula (b ″). In addition, the above-mentioned temperature of the cylinder means an actually measured temperature of the cylinder.

However, the unit of T _OUT and T _IN is in ° C.

  The cylinder of the extruder is usually heated by attaching a plurality of heaters. For example, in the case of 8 divisions, from the hopper inlet (resin supply part) to the extruder outlet (resin discharge part, die connection part). Eight heaters can be attached to the cylinder of the extruder, and the temperature can be set respectively. When C1, C2, C3... C7, C8 are displayed in order, the cylinder temperature at the hopper inlet is In C1, the cylinder temperature at the outlet of the extruder is C8.

  In addition, the kneaded resin composition is supplied to the die and extruded by the above temperature setting, but the temperature of the resin composition in the die is 120 to 300 ° C. (more preferably 150 to 250 ° C.). It is also preferable to adjust the extrusion conditions (set temperature, screw shape, screw rotation speed, etc.) so that the extrusion may become unstable if the temperature is less than 120 ° C, and conversely if the temperature exceeds 300 ° C, The quality of the resin composition may be deteriorated (thermal deterioration), which is not preferable.

  The rotational speed of the screw is selected from the range of 10 to 400 rpm (further, 30 to 300 rpm). If the rotational speed is less than 10 rpm, the drying ability may be insufficient. Conversely, if the rotational speed exceeds 400 rpm, the resin composition The quality of the product may deteriorate (thermal deterioration), which is not preferable.

  There is no restriction | limiting in particular about the preparation speed | rate of the vinyl alcohol type polymer (A) with a moisture content of 70 weight% or less, What is necessary is just to determine arbitrarily by the barrel diameter of an extruder, etc. Moreover, what is necessary is just to supply about the preparation speed | rate of an inorganic compound (B) according to a vinyl alcohol-type polymer (A) so that the compounding quantity of the inorganic compound (B) in the target resin composition etc. may be met.

The residence time (kneading time) of the resin composition in the extruder is selected from the range of 10 to 1800 seconds (more preferably 180 to 1500 seconds, particularly 600 to 1300 seconds), and the residence time is less than 10 seconds. In some cases, sufficient drying may not be possible. Conversely, if it exceeds 1800 seconds, the quality of the resin composition may be deteriorated (thermal degradation), which is not preferable. The pressure applied to the resin composition (resin pressure) is 5. ~300kg / cm ² (more 10 to 200 / cm ²⁾ is selected from the range of, such pressure extrusion exceeds 5 kg / cm ² and less than 300 kg / cm ² may become unstable undesirable. In order to prevent thermal deterioration of the resin composition, it is also preferable to seal the inside of the hopper and around the vent hole with nitrogen.

  In addition, when a closed batch kneading apparatus such as a Banbury mixer, a kneader, or a Brabender is used in the present invention, the vinyl alcohol polymer (A) and the inorganic compound (B) water are added to the apparatus set at a predetermined temperature. Kneading by adding the dispersion liquid all at once or separately, and then kneading for a predetermined time while discharging water from the raw material inlet or the like while appropriately raising the temperature to a predetermined temperature (for example, a temperature equal to or higher than the boiling point of water). What should I do?

  The set temperature of the chamber before the start of kneading is preferably 30 to 120 ° C. (more preferably 45 to 110 ° C., particularly 55 to 100 ° C.). If the set temperature is less than 30 ° C, the melt viscosity of the vinyl alcohol polymer (A) may be too high, which may make it difficult to process. If the set temperature exceeds 120 ° C, the dispersibility of the inorganic compound (B) decreases. When the film is processed, it is not preferable because the appearance and barrier properties of the film may be insufficient.

  There are no particular restrictions on supplying the vinyl alcohol polymer (A) and the inorganic compound (B) aqueous dispersion to the batch kneader, and (1) the vinyl alcohol polymer (A) and the inorganic compound (B) water. Examples include a method of simultaneously supplying the dispersion liquid into the chamber, (2) a method of supplying the inorganic compound (B) aqueous dispersion liquid into the chamber after pre-kneading the vinyl alcohol polymer (A) at less than 120 ° C, and the like. be able to.

  Thus, the vinyl alcohol polymer (A) having a water content of 70% by weight or less and the aqueous dispersion of the inorganic compound (B) are supplied to a batch-type kneader and kneaded. It is necessary to remove water by kneading while appropriately raising the temperature to a temperature equal to or higher than the boiling point of the water. There are no particular restrictions on the removal of moisture, (1) A method of setting the chamber temperature to 100 ° C or higher and kneading while opening the raw material inlet, etc., and (2) High torque Examples include a method in which moisture is evaporated by opening a raw material inlet and the like while raising the resin temperature to 100 ° C. or higher by utilizing shear heat generated by kneading in a state.

Further, the rotational speed of the rotor in the batch-type kneader is not particularly limited, but is preferably in the range of 5 to 400 rpm (more preferably 10 to 200 rpm). If the rotational speed is less than 5 rpm, the kneading action is weak and the inorganic compound ( The dispersion of B) may be insufficient, and if it exceeds 400 rpm, the quality of the resin composition may deteriorate (thermal degradation), which is not preferable.
The kneading time of the resin composition in the batch kneading apparatus is selected from the range of 10 to 1800 seconds (more preferably 180 to 1500 seconds, particularly 600 to 1300 seconds). In contrast, when the drying time exceeds 1800 seconds, the quality of the resin composition may be deteriorated (thermal degradation), which is not preferable.

  Moreover, in this invention, it is preferable to perform the said kneading | mixing on the conditions which satisfy | fill the following Formula (1)-(3) simultaneously.

However, t represents the kneading time (seconds), T ₀ represents the resin temperature (° C.) at the start of kneading, and T ₁ represents the resin temperature (° C.) at the end of kneading.
When the extruder is used, the kneading time (t) can be measured by measuring the elapsed time from when the raw material is charged into the sample charging portion until the resin is discharged from the die. In the case of a batch-type kneader, the measurement can be performed by measuring the elapsed time from the start of kneading after the raw materials are put into the chamber to the end of kneading.
When the extruder is used, the resin temperature (T ₀ ) at the start of kneading can be measured by installing a resin thermometer at the vent portion closest to the sample charging portion. In the case of a batch kneading apparatus, the resin temperature at the start of kneading can be measured using a resin thermometer equipped in the apparatus.
When the extruder is used, the resin temperature (T ₁ ) at the end of the kneading can be measured by installing a resin thermometer in the die part closest to the resin discharge part. In the case of a batch kneader, the resin temperature at the end of kneading can be measured using a resin thermometer equipped in the apparatus.

In the above formula (1), if (T ₁ -T ₀ ) / t is 0.01 or less, coloring due to thermal deterioration may occur due to excessive kneading and the quality may be lowered, while (T ₁ When -T ₀ ) / t is 0.4 or more, water is instantly evaporated and dispersion of the inorganic compound (B) may be insufficient, which is not preferable. Furthermore, it is preferable to satisfy the condition of the following formula (1 ′), particularly satisfying the condition of the following formula (1 ″).

In the above formula (2), if the resin temperature (T ₀ ) at the start of kneading is 30 ° C. or lower, the viscosity of the vinyl alcohol polymer (A) may be too high, which may make processing difficult. When T ₀ is 120 ° C. or higher, the dispersibility of the inorganic compound (B) is lowered, and the film may be insufficient in appearance and barrier properties when processed into a film. Further, it is preferable to satisfy the condition of the following formula (2 ′), particularly the condition of the following formula (2 ″).

Furthermore, in the above formula (3), if the resin temperature (T ₁ ) at the end of kneading is 120 ° C. or lower, the viscosity of the vinyl alcohol polymer (A) may be too high, which may make it difficult to process, When T ₁ is 250 ° C. or higher, coloring and the like due to thermal deterioration may occur and the quality may be lowered. Furthermore, it is preferable to satisfy the condition of the following formula (3 ′), and particularly satisfy the condition of the following formula (3 ″).

A temperature gradient is preferably applied between the resin temperatures T ₀ and T ₁ . That is, it is preferable to appropriately set the heater temperature of the kneading apparatus so that the resin temperature increases from T ₀ to T _{1 according} to a predetermined temperature gradient. There is no particular limitation on the method of applying the temperature gradient, which may be continuous or discontinuous. However, from the viewpoint of the characteristics of the obtained resin composition, it is continuous (for example, linear or quadratic function). It is preferable to apply a temperature gradient to the above.

Resin temperatures T ₀ and T ₁ , kneading time (t), temperature gradient and application method, etc. are the types of vinyl alcohol polymer (A) and inorganic compound (B) used, water content, kneading used. It can be set as appropriate depending on the capacity of the device, the number of revolutions, the temperature adjustment capability, and the like.

In the kneading satisfying the above formulas (1) to (3), for example, when an extruder is used, vinyl alcohol is used in an extruder in which a plurality of heaters are mounted on the cylinder of the extruder from the hopper inlet to the extruder outlet. system polymer (a) and the inorganic compound (B) an aqueous dispersion simultaneously or another on, respectively of the resin temperature T of the cylinder temperature at the outlet of the extruder from the hopper inlet section ₀ and T ₁ are each the above formula (2 ) And (3), and the kneading time (t) in the extruder can be set to satisfy the above formula (1). In this case, it is preferable to apply a temperature gradient between the inlet and the outlet of the extruder.

When using a closed batch kneading apparatus such as a Banbury mixer, for example, after setting the temperature of the kneading apparatus so that the resin temperature (T ₀ ) satisfies the above formula (2), the vinyl alcohol polymer (A ) And the inorganic compound (B) aqueous dispersion are charged all at _once or separately, and it takes a certain time to satisfy the above formula (1) until the resin temperature (T ₁ ) reaches a temperature satisfying the above formula (3). And kneading while raising the temperature.

Thus, a resin composition having a target moisture content of 5% by weight or less can be obtained. In order to obtain such a moisture content, for example, in the method using the above twin screw extruder, various conditions are satisfied. This adjustment is possible by adjusting the resin temperature (set temperature of the extruder, screw shape, etc.) and the discharge amount (screw rotation speed, resin charge amount, etc.). When the water content exceeds 5% by weight, the melt viscosity tends to increase in the region where the shear rate of the obtained resin composition is low, and there is a possibility that streaks occur during re-startup processing and the film appearance is lowered. Is not preferable. Further, the water content is more preferably 2% by weight or less, and particularly preferably 0.5% by weight or less, so that troubles such as foaming during melt molding (extrusion molding, injection molding, etc.) after drying are reduced. It is preferable in that it can be performed.
In the present invention, the water content in the resin composition must be 5% by weight or less by the kneading. Therefore, the present invention does not include a method of obtaining a water content of 5% by weight or less by obtaining a resin composition having a water content of more than 5% by kneading and then drying.

  Furthermore, after obtaining a resin composition having a moisture content of 5% by weight or less by the above method, a known drying treatment (hot air drying, dielectric heating drying) is performed as necessary for the purpose of readjustment of the moisture content of the resin composition. , Microwave irradiation drying, etc.) can also be performed together.

  Thus, in the resin composition obtained by the production method of the present invention, conventionally known plasticizers, heat stabilizers, light stabilizers, ultraviolet absorbers are mixed, mixed, kneaded, or molded according to the purpose. Anti-aging agents, pigments, colorants, natural fibers, various inorganic particles, various fillers, antistatic agents, mold release agents, plasticizers, fragrances, lubricants, crosslinking (vulcanizing) agents, crosslinking (vulcanizing) accelerators, Various lacquering agents such as a crystal nucleating agent, a crystallization accelerator, a flame retardant, a foaming agent, a softening agent, an antiseptic, and an antibacterial and anti-drug agent may be added.

  The resin composition obtained by the production method of the present invention is frequently used for molded products, and is molded into films, sheets, containers, fibers, rods, tubes, various molded products, etc. by melt molding, etc. It is also possible to use the product (for example, when the collected product is reused) again for melt molding. As such melt molding methods, extrusion molding methods (T-die extrusion, inflation extrusion, blow molding, melt spinning, profile extrusion, etc.) and injection molding methods are mainly employed. The melt molding temperature is often selected from the range of 150 to 300 ° C.

  In particular, when the resin composition obtained by the production method of the present invention is processed into a film, when the extruder is temporarily stopped and restarted, a film having a good appearance can be obtained even after restarting, so that it is industrially productive. Is extremely advantageous.

  In addition, the resin composition obtained by the production method of the present invention can be used as a single molded product, but can exert the effects of the present invention sufficiently when used for a molded product of a laminate, Specifically, it is useful to laminate a thermoplastic resin layer or the like on at least one side of the layer made of the resin composition and use it as a molded product that is a multilayer laminate.

  In manufacturing the laminate, another substrate is laminated on one or both sides of the layer made of the resin composition. As a lamination method, for example, a film or sheet made of the resin composition is thermoplastic. A method of melt-extruding a resin, a method of melt-extruding the resin composition on a substrate such as a thermoplastic resin, a method of co-extruding the resin composition and another thermoplastic resin, and a resin of the present invention Examples thereof include a method of dry laminating a film or sheet comprising the composition and a film or sheet of another substrate using a known adhesive such as an organic titanium compound, an isocyanate compound, a polyester compound, or a polyurethane compound. The resin composition obtained by the production method of the present invention is also preferably subjected to coextrusion molding.

  In the case of co-extrusion, the other resin is polyolefin resin, polyester resin, polyamide resin, copolymer polyamide, polystyrene resin, polyvinyl chloride resin, polyvinylidene chloride, acrylic resin, vinyl ester resin, polyester. Examples include elastomers, polyurethane elastomers, chlorinated polyethylene, chlorinated polypropylene, aromatic and aliphatic polyketones, and aliphatic polyalcohols, and polyolefin resins are preferably used.

  Specific examples of such polyolefin resins include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), very low density polyethylene (VLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), and ethylene. -Vinyl acetate copolymer (EVA), ionomer, ethylene-propylene (block or random) copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene -Methacrylic acid ester copolymer, polypropylene, propylene-α-olefin (α-olefin having 4 to 20 carbon atoms) copolymer, polybutene, polypentene, polymethylpentene or other olefin homo- or copolymer, or these Olefin homo- or copolymerization Examples thereof include polyolefin resins in a broad sense such as those obtained by graft modification with unsaturated carboxylic acids or esters thereof, and blends thereof, among which linear low density polyethylene (LLDPE), low density polyethylene (LDPE). ), Very low density polyethylene (VLDPE), ethylene-vinyl acetate copolymer (EVA), and ionomer are preferable in that they are excellent in bending fatigue resistance, vibration fatigue resistance, and the like of the resulting laminated packaging material.

  Furthermore, a molded product such as a film or a sheet is obtained once from the resin composition obtained by the production method of the present invention, and another substrate is extrusion coated thereon, or a film or sheet of another substrate is adhesive. In addition to the thermoplastic resin, any substrate (paper, metal foil, unstretched, uniaxial or biaxially stretched plastic film or sheet and its inorganic deposit, woven fabric, non-woven fabric, metallic cotton Wood, etc.) can be used.

The layer structure of the laminate is such that the layer made of the resin composition obtained by the production method of the present invention is a (a ₁ , a ₂ ,...), And another substrate, for example, a thermoplastic resin layer is b (b ₁ , b ₂ ,...), As long as it is a film, sheet, or bottle, not only a two-layer structure of a / b but also b / a / b, a / b / a, a ₁ / a _{2 / b, a / b 1} / b 2, b 2 / b 1 / a / b 1 / b 2, b 1 / b 2 / a / b 3 / b 4, a 1 / b 1 / a 2 / b Any combination such as ₂ is possible, and in the filament form, a and b are bimetal type, core (a) -sheath (b) type, core (b) -sheath (a) type, or eccentric core-sheath type, etc. Combinations are possible.

  In the above layer structure, an adhesive resin layer can be provided between the respective layers as required, and various types of such adhesive resins can be used. Contains a carboxyl group obtained by chemically bonding an unsaturated carboxylic acid or its anhydride to an olefin polymer (the above-mentioned polyolefin resin in the broad sense) by an addition reaction or a graft reaction. Examples of the modified olefin polymer include maleic anhydride graft-modified polyethylene, maleic anhydride graft-modified polypropylene, maleic anhydride graft-modified ethylene-propylene (block or random) copolymer, and maleic anhydride. Acid graft modified ethylene-ethyl acrylate copolymer, maleic anhydride graft modified Ethylene - one or more mixtures selected from vinyl acetate copolymers and the like as preferred. The amount of the unsaturated carboxylic acid or anhydride thereof contained in the olefin polymer at this time is preferably 0.001 to 3% by weight, more preferably 0.01 to 1% by weight, particularly preferably 0.00. 03 to 0.5% by weight. If the amount of modification in the modified product is small, the adhesiveness may be insufficient. On the other hand, if the amount is too large, a crosslinking reaction may occur and the moldability may be deteriorated. In addition, these adhesive resins are blended with the resin composition obtained by the production method of the present invention, other rubber / elastomer components such as EVOH, polyisobutylene, ethylene-propylene rubber, and the resin of the b layer. It is also possible. In particular, blending a polyolefin resin different from the base polyolefin resin of the adhesive resin is useful because the adhesiveness may be improved.

  The thickness of each layer of the laminate cannot be generally stated depending on the layer configuration, the type of b, the application and container form, the required physical properties, etc. Usually, the a layer is 5 to 500 μm (more preferably 10 to 200 μm), b The layer is selected from the range of about 5 to 5000 μm (further, 30 to 1000 μm), and the adhesive resin layer is about 5 to 400 μm (further, 10 to 150 μm). If the a layer is less than 5 μm, the gas barrier property is insufficient, and the thickness control becomes unstable. On the other hand, if it exceeds 500 μm, the bending fatigue resistance is inferior and not economical, and the b layer is less than 5 μm. On the other hand, if it exceeds 5000 μm, the bending fatigue resistance is inferior and the weight increases, which is not preferable. If the adhesive resin layer is less than 5 μm, the interlayer adhesion is insufficient, and the thickness control becomes unstable. If it exceeds 400 μm, the weight increases, and it is not economical and not preferable. In addition, in order to improve molding processability and various physical properties, the above-mentioned various additives, modifiers, fillers, other resins, and the like are added to each layer of the laminate in a range that does not impair the effects of the present invention. You can also.

  The laminate is used in various shapes as it is, but it is also preferable to perform a stretching treatment in order to further improve the physical properties of the laminate, and the stretching may be either uniaxial stretching or biaxial stretching. It may be present, and it is better to perform stretching at as high a magnification as possible, and molded products such as stretched films and stretched sheets, stretched containers, stretched bottles, etc. that do not cause pinholes, cracks, stretch unevenness, delamination, etc. during stretching. Is obtained.

  As a stretching method, in addition to a roll stretching method, a tenter stretching method, a tubular stretching method, a stretching blow method, and the like, a deep drawing method, a vacuum / pressure forming method, or the like that has a high stretching ratio can be employed. In the case of biaxial stretching, both a simultaneous biaxial stretching method and a sequential biaxial stretching method can be employed. The stretching temperature is selected from the range of about 60 to 170 ° C, preferably about 80 to 160 ° C.

  It is also preferable to perform heat setting after the completion of stretching. The heat setting can be carried out by a known means, and the heat treatment is performed at 80 to 170 ° C., preferably 100 to 160 ° C. for about 2 to 600 seconds while keeping the stretched film in a tension state. For example, when a cup or tray-like multilayer container is obtained from a multilayer sheet or multilayer film, a drawing method is employed, specifically, vacuum forming method, pressure forming method, vacuum / pressure forming method, plug assist type vacuum / pressure forming method. Law.

  Furthermore, when a tube or bottle-shaped multilayer container is obtained from a multilayer parison (a hollow tubular preform before blow), a blow molding method is adopted. Specifically, an extrusion blow molding method (double-head type, mold transfer type, Parison shift type, rotary type, accumulator type, horizontal parison type, etc.), cold parison type blow molding method, injection blow molding method, biaxial stretch blow molding method (extrusion type cold parison biaxial stretch blow molding method, injection type cold) Parison biaxial stretch blow molding method, injection molding inline biaxial stretch blow molding method, etc.).

  In addition, when used for heat shrink packaging applications such as raw meat, processed meat, cheese, etc., after heat stretching after stretching, it is a product film, and after storing the above raw meat, processed meat, cheese, etc. in the film, The film is heat-shrinked at 50 to 130 ° C., preferably 70 to 120 ° C. for about 2 to 300 seconds, and the film is heat-shrinked for close-packaging.

  The shape of the laminate thus obtained may be any shape, and examples thereof include films, sheets, tapes, bottles, pipes, filaments, profile cross-section extrudates, and the like. In addition, the obtained laminate can be subjected to heat treatment, cooling treatment, rolling treatment, printing treatment, dry lamination treatment, solution or melt coating treatment, bag making processing, deep drawing processing, box processing, tube processing, split processing, etc. It can be carried out.

  Containers made of cups, trays, tubes, bottles, etc. and bags and lids made of stretched films obtained as above are seasonings such as mayonnaise and dressing, fermented foods such as miso, salad oil, etc. It is useful as various containers such as oil and fat foods, beverages, cosmetics, pharmaceuticals, detergents, cosmetics, industrial chemicals, agricultural chemicals, fuels, etc., but the laminate of the present invention is particularly jelly, pudding, yogurt, mayonnaise, miso, etc. It is useful for heat-stretched molded containers such as cup-shaped containers for semi-solid foods and seasonings, and tray-shaped containers for raw meat and processed meat products (ham, bacon, wiener, etc.).

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but these do not limit the present invention.
In the following examples, “%” and “part” are based on weight unless otherwise specified.

Example 1
EVOH (A) having a water content of 28% by weight [Soarnol D2908 manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: ethylene content 29 mol%, saponification degree 99.8 mol%] 139 parts [EVOH 100 parts (solid content)], powder -Like natural montmorillonite (B) [Kunimine Industry Co., Ltd. Kunipia F: swelling degree (measured according to the standard test method volume method of the Japan Bentonite Industry Association) 98 ml / 2 g] aqueous dispersion (solid content concentration 60%) 8.3 parts [5 parts of natural montmorillonite (solid content)] are supplied to a Brabender apparatus (made by Brabender; model PLE331) set at a chamber temperature of 60 ° C. and a rotor speed of 70 rpm, and the raw material input port is supplied. The mixture was sealed and kneaded for 3 minutes until the torque reached the rising range. Thereafter, the chamber set temperature was changed to 110 ° C., kneading was continued while the raw material inlet was opened and water was evaporated, and kneading was continued for 17 minutes until no steam was generated from the raw material inlet. At this time, the resin temperature was gradually raised by shearing heat generated by kneading, and increased to 173 ° C. at the end of kneading. Thereafter, the resin was taken out from the chamber to obtain a resin composition having a water content of 0.3% by weight.

The kneading time (t) from the start to the end of kneading was 1200 seconds. The resin temperature (T ₀ ) at the start of kneading was 60 ° C., and the resin temperature (T ₁ ) at the end of kneading was 173 ° C.

The obtained resin composition was pulverized into chips, and then supplied to a single screw extruder equipped with a T die, and a 30 μm thick film was formed under the following conditions.
[Film forming conditions with a single screw extruder]
Screw inner diameter 40mm
L / D 28
Screw shape Full flight type screw compression ratio 3.8
Screw rotation speed 50rpm
T die Coat hanger type die width 450mm
Temperature setting C1: 180 ° C H: 210 ° C
C2: 210 ° C D: 210 ° C
C3: 220 ° C
C4: 220 ° C
Cooling roll temperature 90 ° C
Roll take-up speed 12m / min
Air gap 90mm
After processing for 10 hours under these conditions, the operation of the extruder was stopped. Then, after 3 hours had passed while maintaining the temperature setting, the extruder was started up again, and a 30 μm thick film was processed under the same conditions as before stopping. The following evaluation was performed on the film obtained after the re-startup (evaluation of the film after 1 hour of re-startup).

(Film appearance after restart)
In the film obtained after re-startup, the number of streaks having a width of 100 μm or more in 10 cm × 10 cm was measured and evaluated according to the following criteria.
◎: 1 or less ○: 2-5
×: 6 or more

(Haze value of the film after restarting)
Using a haze meter “NDH2000” manufactured by Nippon Denshoku Co., Ltd., the haze value of the film obtained after re-startup was measured according to JIS K7105 and evaluated according to the following criteria.
A: Haze value <10
○: 10 ≦ haze value <20
×: 20 ≦ haze value

( Reference Example 1 )
In Example 1, it carried out similarly except having changed into 15.2 parts [natural montmorillonite 5 parts (solid content)] of the aqueous dispersion (solid content concentration 33%) of natural montmorillonite (B), and the moisture content was 0.3 A weight percent resin composition was obtained. The kneading time (t) from the start to the end of kneading was 1450 seconds. The resin temperature (T ₀ ) at the start of kneading was 57 ° C., and the resin temperature (T ₁ ) at the end of kneading was 171 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Example 2 )
In Example 1, it carried out similarly except having changed into 6.3 parts of natural montmorillonite (B) aqueous dispersion (solid content concentration 80%) [5 parts of natural montmorillonite (solid content)], and the water content was 0.3. A weight percent resin composition was obtained. The kneading time (t) from the start to the end of kneading was 1000 seconds. The resin temperature (T ₀ ) at the start of kneading was 60 ° C., and the resin temperature (T ₁ ) at the end of kneading was 173 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Example 3 )
In Example 1, EVOH (A) having a water content of 13% by weight [Soarnol D2908 manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: ethylene content 29 mol%, saponification degree 99.8 mol%] 115 parts [EVOH 100 parts (solid content The resin composition having a water content of 0.3% by weight was obtained in the same manner as in the above. The kneading time (t) from the start to the end of kneading was 720 seconds. The resin temperature (T ₀ ) at the start of kneading was 60 ° C., and the resin temperature (T ₁ ) at the end of kneading was 173 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

( Reference Example 2 )
In Example 1, EVOH (A) having a water content of 58% by weight [Soarnol D2908 manufactured by Nippon Synthetic Chemical Industry Co., Ltd .: ethylene content 29 mol%, saponification degree 99.8 mol%] 238 parts [EVOH 100 parts (solid content The resin composition having a water content of 0.3% by weight was obtained in the same manner as in the above. The kneading time (t) from the start to the end of kneading was 1650 seconds. The resin temperature (T ₀ ) at the start of kneading was 58 ° C., and the resin temperature (T ₁ ) at the end of kneading was 170 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Example 4 )
In Example 1, it carried out similarly except having changed into 16.7 parts [natural montmorillonite 10 parts (solid content)] of the aqueous dispersion (solid content concentration 60%) of natural montmorillonite (B), and the moisture content was 0.3 A weight percent resin composition was obtained. The kneading time (t) from the start to the end of kneading was 1200 seconds. The resin temperature (T ₀ ) at the start of kneading was 60 ° C., and the resin temperature (T ₁ ) at the end of kneading was 183 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Reference Example 3 )
In Example 1, the same procedure was performed except that the chamber setting temperature before kneading was changed to 100 ° C. and the chamber setting temperature after the torque reached the rising range was changed to 140 ° C., and the resin composition had a moisture content of 0.3% by weight. I got a thing. The kneading time (t) from the start to the end of kneading was 390 seconds. The resin temperature (T ₀ ) at the start of kneading was 96 ° C., and the resin temperature (T ₁ ) at the end of kneading was 185 ° C. About the obtained resin composition, the film process was performed similarly to Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Reference Example 4 )
139 parts EVOH (A) 139 parts [EVOH 100 parts (solid content)] having the same water content as in Example 1 and 8.3 parts of powdered natural montmorillonite (B) (solid content concentration 60%) [5 parts of natural montmorillonite (solid content)] is supplied to a twin screw extruder equipped with a strand die, kneaded under the following conditions, the strand is passed through a water bath, cooled and cut with a pelletizer, Resin composition pellets having a water content of 0.3% by weight were obtained.

[Conditions for pelletization by twin screw extruder]
Equipment: 57mmφ twin screw extruder (L / D = 44)
Strand die shape: 12-hole screen mesh with a diameter of 3.5 mmφ: 90/90 mesh
Vent: C6 part and C9 part are opened, C12 part is in vacuum suction hopper: Nitrogen sealing is performed Screw rotation speed: 33 rpm
Cylinder temperature setting: C1: 60 ° C, C2-C4: 95 ° C, C5-C6: 100 ° C, C7: 150 ° C, C8-C13: 170 ° C, AD: 180 ° C, D: 180 ° C

The residence time (kneading time) in the extruder of the resin composition was adjusted to 480 seconds. The resin temperature (T ₀ ) at the hopper inlet was adjusted to 65 ° C., and the resin temperature (T ₁ ) at the extruder outlet was adjusted to 180 ° C. About the obtained resin composition pellet, film processing was performed in the same manner as in Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Reference Example 5 )
139 parts EVOH (A) 139 parts [EVOH 100 parts (solid content)] having the same water content as in Example 1 and 8.3 parts of powdered natural montmorillonite (B) (solid content concentration 60%) [5 parts of natural montmorillonite (solid content)] is supplied to a twin screw extruder equipped with a strand die, kneaded under the following conditions, the strand is passed through a water bath, cooled and cut with a pelletizer, Resin composition pellets having a water content of 0.3% by weight were obtained.

[Conditions for pelletization by twin screw extruder]
Equipment: 57mmφ twin screw extruder (L / D = 44)
Strand die shape: 12-hole screen mesh with a diameter of 3.5 mmφ: 90/90 mesh
Vent: C6 part and C9 part are opened, C12 part is in vacuum suction hopper: Nitrogen sealing is performed Screw rotation speed: 90 rpm
Cylinder temperature setting: C1: 60 ° C, C2 to C4: 95 ° C, C5 to C6: 100 ° C, C7: 150 ° C, C8 to C13: 190 ° C, AD: 190 ° C, D: 190 ° C

The residence time (kneading time) in the extruder of the resin composition was adjusted to 320 seconds. The resin temperature (T ₀ ) at the hopper inlet was adjusted to 65 ° C., and the resin temperature (T ₁ ) at the extruder outlet was adjusted to 190 ° C. About the obtained resin composition pellet, film processing was performed in the same manner as in Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Comparative Example 1)
139 parts of EVOH (A) having the same water content of 28% by weight as in Example 1 [100 parts of EVOH (solid content)] and 5 parts of powdered natural montmorillonite (B) as in Example 1 [without water dispersion] Supply to a twin screw extruder equipped with a die, knead under the following conditions, pass the strand through a water tank, cool and cut with a pelletizer, a resin composition having a moisture content of 0.3 wt% Pellets were obtained.

[Conditions for pelletization by twin screw extruder]
Equipment: 57mmφ twin screw extruder (L / D = 44)
Strand die shape: 12-hole screen mesh with a diameter of 3.5 mmφ: 90/90 mesh
Vent: C6 part and C9 part are opened, C12 part is in vacuum suction hopper: Nitrogen sealing is performed Screw rotation speed: 100 rpm
Cylinder temperature setting: C1: 60 ° C, C2 to C4: 95 ° C, C5 to C6: 100 ° C, C7: 150 ° C, C8 to C13: 200 ° C, AD: 200 ° C, D: 200 ° C

The residence time (kneading time) in the extruder of the resin composition was adjusted to 300 seconds. The resin temperature (T ₀ ) at the hopper inlet was adjusted to 65 ° C., and the resin temperature (T ₁ ) at the extruder outlet was adjusted to 200 ° C. About the obtained resin composition pellet, film processing was performed in the same manner as in Example 1, and the same evaluation was performed. The results are shown in Table 1.

(Comparative Example 2)
Powdered natural montmorillonite (B) is dispersed in water as an aqueous dispersion with a solid content concentration of 8%, and this is supplied from the C3 vent part of the twin screw extruder, and the pelletizing conditions are changed as follows. Except for the above, kneading was carried out in the same manner as in Comparative Example 1 to obtain a resin composition pellet having a water content of 38% by weight.
Cylinder temperature setting: C1: 60 ° C, C2-C13: 95 ° C, AD: 95 ° C, D: 95 ° C

The residence time (kneading time) in the extruder of the resin composition was adjusted to 300 seconds. The resin temperature (T ₀ ) at the hopper inlet was adjusted to 65 ° C., and the resin temperature (T ₁ ) at the extruder outlet was adjusted to 95 ° C. The obtained resin composition pellets were vacuum-dried at 60 ° C. to obtain a resin composition having a water content of 0.3% by weight, and then film processing was performed in the same manner as in Example 1 and the same evaluation was performed. The results are shown in Table 1.

  As shown in Table 1 above, the resin compositions obtained in the examples had good film appearance after re-launching and haze values, whereas the resin compositions obtained in the comparative examples were The film appearance after re-startup and the haze value were not satisfactory.

  The resin composition obtained by the production method of the present invention is applied to films, sheets, containers, etc., and is useful as various packaging materials such as general foods, retort foods, pharmaceuticals, industrial chemicals, agricultural chemicals, and various resins. It is also effective to use in a stack, and is particularly useful for containers such as gasoline tanks and agricultural chemical bottles.

Claims (6)

In producing the vinyl alcohol polymer (A) and the inorganic compound (B) resin composition containing a water content of 5 wt% to 70 wt% of the vinyl alcohol polymer (A), solid In producing a resin composition by removing moisture while kneading an aqueous dispersion of inorganic compound (B) having a concentration of 30 to 99% by weight to make the water content in the resin composition 5% by weight or less , the kneading time is set to The manufacturing method of the resin composition characterized by setting it as 600-1300 second . The method for producing a resin composition according to claim 1, wherein kneading is performed under the conditions satisfying the following formulas (1) to (3) simultaneously.

However, t represents the kneading time (seconds), T ₀ represents the resin temperature (° C.) at the start of kneading, and T ₁ represents the resin temperature (° C.) at the end of kneading.   The method for producing a resin composition according to claim 1 or 2, wherein the solid content concentration of the inorganic compound (B) aqueous dispersion is 10% by weight or more. The inorganic compound (B) is the preparation of the resin composition according to any one of claims 1 to 3 is a layered inorganic compound. Vinyl alcohol polymer (A) is an ethylene - preparation of the resin composition according to any one of claims 1 to 4 is a vinyl acetate copolymer saponification product. The resin composition obtained by the production method of the resin composition according to any one of claims 1 to 5.