Method for producing resin composition, composition and pellets

Abstract

To provide a method for producing a resin composition having a small difference between a YI value in the case of only a polyamide resin and a YI value of the resin composition after having been mixed with a talc, and a resin composition and a pellet.SOLUTION: When the total of polyamide resin and plate-like talc having a bulk density of 0.30 g / cm3 or more is 100 mass%, a method for producing a resin composition includes melt-kneading the polyamide resin and the a plate-like talc in such a manner that the amount of the plate-like talc becomes 10-40 mass%, then extruding the polyamide resin and the plate-like talc using an extruder.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a resin composition, the composition, and pellets. [Background technology]

[0002] Blending talc into polyamide resins has been studied for some time. For example, Patent Document 1 discloses a polyamide resin composition in which 0.2 to 40 parts by mass of talc is blended with 100 parts by mass of polyamide resin, the talc consisting of (a) untreated talc and (b) treated talc, and the blending ratio (mass ratio) of (a) to (b) is 0.02≦(b) / (a)≦50, and a molded article thereof. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-070580 Summary of the Invention [Problem to be solved by the invention]

[0004] When talc is blended with polyamide resin, the resulting pellets and molded products tend to have a higher YI (Yellow Index) value. Depending on the application, the difference in YI value (ΔYI) between the neat polyamide resin and the polyamide resin after blending and melt-kneading with talc may be a problem. The present invention aims to solve the above problems, and provides a method for producing a resin composition containing a polyamide resin and talc, which can provide a resin composition in which the difference in YI value between the polyamide resin alone and the resin composition after melt-kneading with talc is small, as well as a composition and pellets. [Means for solving the problem]

[0005] Based on the above problem, the inventors have conducted research and found that the bulk density of the powder is 0.30 g / cm 3 It has been found that the above-mentioned problems can be solved by using the platy talc described above. Specifically, the above problems have been solved by the following means. <1> Polyamide resin and bulk density of 0.30 g / cm 3 and the platy talc described above in a proportion such that the platy talc accounts for 10 to 40 mass% when the total of the polyamide resin and the platy talc is 100 mass%, followed by extruding the mixture in an extruder. <2> The platy talc is fed into an extruder by a side feed. <1> A method for producing the resin composition described in claim 1. <3> The platy talc is fed to the extruder by side feeding in two or more batches. <1> A method for producing the resin composition described in claim 1. <4> The Q / Ns of the extruder is 0.1 to 0.4. <1> ~ <3> wherein Q means a discharge rate (unit: kg / hour), and Ns means a rotation speed (unit: rpm). <5> The temperature of the resin composition when extruded from the extruder is 280 to 380°C. <1> ~ <4> 10. A method for producing the resin composition according to any one of the above items. <6> The aspect ratio of the platy talc is greater than 18. <1> ~ <5> 10. A method for producing the resin composition according to any one of the above items. <7> The polyamide resin is a semi-aromatic polyamide resin. <1> ~ <6> 10. A method for producing the resin composition according to any one of the above items. <8> the polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, 50 mol % or more of the diamine-derived structural units are derived from xylylenediamine, and 30 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms; <1> ~ <6> 10. A method for producing the resin composition according to any one of the above items. <9> the polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, 50 mol % or more of the diamine-derived structural units are derived from xylylenediamine, 30 to 99 mol % of the dicarboxylic acid-derived structural units are derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms, and 1 to 70 mol % are derived from isophthalic acid; <1> ~ <6> 10. A method for producing the resin composition according to any one of the above items. <10> The oxygen permeability coefficient of the polyamide resin is 0.1cc·mm / (m 2 ·day·atm) or less, <1> ~ <9> 10. A method for producing the resin composition according to any one of the above items. <11> The resin composition is in the form of pellets. <1> ~ <10> 10. A method for producing the resin composition according to any one of the above items. <12> Polyamide resin and bulk density of 0.30 g / cm 3 The platy talc is The composition, wherein the platy talc accounts for 10 to 40% by mass when the total of the polyamide resin and the platy talc is 100% by mass. <13> <1> ~ <11> 2. Pellets produced by the method for producing a resin composition according to any one of the above. <14> <12> 10. A pellet formed from the composition of claim 1. [Effects of the Invention]

[0006] The present invention makes it possible to provide a resin composition in which the difference between the YI value of the polyamide resin alone and the YI value of the resin composition after blending with talc is small. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified.

[0008] The method for producing the resin composition of this embodiment comprises mixing a polyamide resin and a polymer having a bulk density of 0.30 g / cm 3 The method includes melt-kneading the polyamide resin and the platy talc described above in a proportion of 10 to 40% by mass, where the total of the polyamide resin and the platy talc is 100% by mass, and extruding the mixture in an extruder. This configuration makes it possible to provide a resin composition in which the difference in YI value between the raw polyamide resin alone and the resin composition after blending with talc is small. The reason for this is speculation, but it is thought that the use of bulky platy talc allows a larger amount of talc to be introduced into the extruder, shortening the residence time of the polyamide resin in the extruder and effectively suppressing an increase in the YI value of the resulting resin composition. The details of this embodiment will be described below.

[0009] <Raw materials> In this embodiment, polyamide resin and a bulk specific gravity of 0.30 g / cm 3 The raw material is a composition containing the above-described platy talc, wherein the platy talc accounts for 10 to 40% by mass when the total of the polyamide resin and the platy talc is 100% by mass. As will be described in detail later, these raw materials do not need to be fed simultaneously to the extruder, and are generally fed separately. Furthermore, in this embodiment, the raw material composition may contain other components. The composition as a raw material will be described below. Hereinafter, unless otherwise specified, the polyamide resin and platy talc refer to the raw material polyamide resin and raw material platy talc.

[0010] <<Polyamide resin>> The polyamide resin used in this embodiment may be an aliphatic polyamide resin or a semi-aromatic polyamide resin, and is preferably a semi-aromatic polyamide resin. Use of a semi-aromatic polyamide resin tends to result in a resin composition with better barrier properties. Examples of aliphatic polyamide resins include one or more of polyamide 6, polyamide 66, polyamide 46, polyamide 6 / 66 (a copolymer consisting of a polyamide 6 component and a polyamide 66 component), polyamide 610, polyamide 612, polyamide 11, and polyamide 12. Examples of semi-aromatic polyamide resins include resins composed of diamine-derived structural units and dicarboxylic acid-derived structural units, in which 30 to 70 mol % of the total structural units of the diamine-derived structural units and dicarboxylic acid-derived structural units contain aromatic rings. Resins in which 40 to 60 mol % of the total structural units of the diamine-derived structural units and dicarboxylic acid-derived structural units contain aromatic rings are preferred. Use of such semi-aromatic polyamide resins can enhance the mechanical strength of the resulting molded article. Examples of semi-aromatic polyamide resins include polyamide 6T, polyamide 9T, polyamide 6I / 6T, and the xylylenediamine-based polyamide resins described below. Xylylenediamine-based polyamide resins are preferred. Use of xylylenediamine-based polyamide resins tends to result in resin compositions with superior barrier properties.

[0011] In addition, when the semi-aromatic polyamide resin is formed from diamine-derived structural units and dicarboxylic acid-derived structural units, structural units other than these are not completely excluded, and it goes without saying that the semi-aromatic polyamide resin may contain structural units derived from lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid. In the present invention, the total of the diamine-derived structural units and dicarboxylic acid-derived structural units in the semi-aromatic polyamide resin preferably accounts for 90 mol% or more of all structural units, more preferably 95 mol% or more, and even more preferably 98 mol% or more.

[0012] The polyamide resin used in this embodiment is preferably a xylylenediamine-based polyamide resin composed of diamine-derived structural units and dicarboxylic acid-derived structural units, in which 50 mol % or more of the diamine-derived structural units are derived from xylylenediamine.

[0013] More specifically, in this embodiment, the xylylenediamine-based polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, and it is preferred that 50 mol % or more of the diamine-derived structural units are derived from xylylenediamine, and 30 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms. Use of such a xylylenediamine-based polyamide resin tends to result in a resin composition with even better barrier properties.

[0014] Furthermore, in this embodiment, the xylylenediamine-based polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, with 50 mol% or more of the diamine-derived structural units being derived from xylylenediamine, and 30 mol% to 100 mol% (preferably 40 to 100 mol%) of the dicarboxylic acid-derived structural units being derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms, and 0 to 70 mol% (preferably 0 to 60 mol%) being derived from isophthalic acid. Here, the total of the structural units derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms and the structural units derived from isophthalic acid is 100 mol% or less of the dicarboxylic acid-derived structural units, preferably 90 to 100 mol%, and more preferably 95 to 100 mol%.

[0015] In particular, xylylenediamine-based polyamide resins are composed of diamine-derived structural units and dicarboxylic acid-derived structural units, with 50 mol% or more of the diamine-derived structural units being derived from xylylenediamine, 30 to 99 mol% (preferably 40 to 99 mol%) of the dicarboxylic acid-derived structural units being derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms, and 1 to 70 mol% (preferably 1 to 60 mol%) being derived from isophthalic acid. Use of a polyamide resin containing isophthalic acid-derived structural units tends to further improve secondary processability.

[0016] In the xylylenediamine-based polyamide resin used in this embodiment, preferably 60 mol% or more, more preferably 70 mol% or more, even more preferably 80 mol% or more, still more preferably 90 mol% or more, and even more preferably 95 mol% or more of the diamine-derived structural units are derived from xylylenediamine. The xylylenediamine is usually selected from meta-xylylenediamine and / or para-xylylenediamine, and preferably 30 mol% or more, more preferably 50 mol% or more, even more preferably 70 mol% or more, still more preferably 80 mol% or more, and even more preferably 90 mol% or more is meta-xylylenediamine.

[0017] Diamines other than metaxylylenediamine and paraxylylenediamine that can be used as raw diamine components for xylylenediamine-based polyamide resins include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine; 1,3-bis( Examples of the diamine include alicyclic diamines such as bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane; and diamines having an aromatic ring such as bis(4-aminophenyl)ether, paraphenylenediamine, and bis(aminomethyl)naphthalene. These diamines can be used alone or in combination of two or more.

[0018] The raw material dicarboxylic acid component of the xylylenediamine-based polyamide resin is not particularly limited in type, but examples include α,ω-straight-chain aliphatic dicarboxylic acids having 4 to 15 carbon atoms, as described below, and dicarboxylic acids other than these α,ω-straight-chain aliphatic dicarboxylic acids having 4 to 15 carbon atoms.

[0019] Specifically, the proportion of structural units derived from α,ω-linear dicarboxylic acids having 4 to 15 carbon atoms in the structural units derived from dicarboxylic acids is preferably 40 mol% or more, more preferably 45 mol% or more, and may even be 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 90 mol% or more. Furthermore, the proportion of structural units derived from α,ω-linear dicarboxylic acids having 4 to 15 carbon atoms in the structural units derived from dicarboxylic acids is preferably 98 mol% or less, more preferably 97 mol% or less, and even more preferably 95 mol% or less. Examples of the α,ω-linear aliphatic dicarboxylic acids having 4 to 15 carbon atoms include succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, adipic acid, sebacic acid, undecanedioic acid, and dodecanedioic acid. These can be used alone or in combination of two or more. Among these, adipic acid or sebacic acid are more preferred, and adipic acid is even more preferred, as they provide excellent barrier properties for polyamide resins and excellent thermal stability when molded in a molten state.

[0020] On the other hand, the proportion of constituent units derived from other dicarboxylic acids (for example, aromatic dicarboxylic acids or isophthalic acid) in the constituent units derived from the dicarboxylic acid is preferably 2 mol% or more, more preferably 3 mol% or more, and even more preferably 5 mol% or more. Furthermore, the proportion of constituent units derived from isophthalic acid in the constituent units derived from the dicarboxylic acid is preferably 60 mol% or less, preferably 55 mol% or less, and may even be 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 10 mol% or less.

[0021] Examples of dicarboxylic acid components other than the above-mentioned α,ω-linear aliphatic dicarboxylic acids having 4 to 15 carbon atoms include phthalic acid compounds such as terephthalic acid and orthophthalic acid, and isomers of naphthalenedicarboxylic acids such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and these can be used alone or in combination of two or more.

[0022] The polyamide resin used in this embodiment preferably has excellent oxygen barrier properties. Specifically, the polyamide resin has an oxygen permeability coefficient of 0.1 cc·mm / (m 2 ·day·atm) or less, and 0.08cc·mm / (m 2 ·day·atm) or less is more preferable, and 0.06cc·mm / (m 2 ·day·atm) or less is more preferable. The lower limit is 0 cc·mm / (m 2 ·day·atm) is ideal, but 0.001cc·mm / (m 2 ·day·atm) or more is practical. The oxygen permeability coefficient is measured as described in the Examples section below.

[0023] In this embodiment, the raw material composition preferably contains 60% by mass or more, more preferably 65% ​​by mass or more, of polyamide resin. The upper limit of the resin component content in the resin composition is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, and even more preferably 75% by mass or less. In this embodiment, only one type of polyamide resin may be used as a raw material, or two or more types may be used. When two or more types are used, the total amount is preferably within the above range.

[0024] <<Bulk density is 0.30g / cm 3More than that, plate-like talc >> In this embodiment, the raw material composition has a bulk density of 0.30 g / cm 3 The platy talc having a bulk density of 0.30 g / cm is contained in an amount of 10 to 40% by mass when the total of the polyamide resin and the platy talc is taken as 100% by mass. 3 By including platy talc of this amount or more, a larger amount of talc can be introduced into the extruder. Furthermore, when the total of the polyamide resin and the platy talc is taken as 100% by mass, by including 10% by mass or more of the platy talc, a resin composition with better barrier properties tends to be obtained. Furthermore, by including 40% by mass or less, impact resistance tends to be further improved.

[0025] The bulk density of plate-shaped talc is 0.35 g / cm 3 It is preferable that the concentration is 0.38 g / cm or more. 3 More preferably, it is 0.40 g / cm or more. 3 More preferably, it is 0.42 g / cm or more. 3 The upper limit of the bulk density of the platy talc is 1.5 g / cm. 3 Preferably, it is 0.8 g / cm or less. 3 More preferably, it is 0.60 g / cm or less. 3 More preferably, it is 0.56 g / cm or less. 3 More preferably, it is 0.50 g / cm or less. 3 By making the content equal to or less than the upper limit, the platy talc has better dispersibility, and the barrier properties tend to be further improved.

[0026] The platy talc used in this embodiment (raw material platy talc before being fed to the extruder) preferably has an aspect ratio of greater than 18. The use of such talc increases the Q / Ns value, tending to further improve the barrier properties of the resulting resin composition. The aspect ratio is preferably 20 or more, more preferably 21 or more, even more preferably 25 or more, even more preferably 30 or more, even more preferably 35 or more, even more preferably 38 or more, and particularly preferably 40 or more. The upper limit of the aspect ratio is not particularly specified, but is preferably 60 or less, more preferably 55 or less, even more preferably 51 or less, and even more preferably 48 or less. By setting the aspect ratio at or below the upper limit, the secondary processability of the resin composition tends to be more excellent. The aspect ratio of platy talc is measured by observing the particle with a scanning electron microscope at 2000x to 30000x magnification, observing the ratio of the thickness to the length (length / thickness) of the cross section of 50 particles whose cross sections can be observed, and calculating the arithmetic average of the ratios of any five particles.

[0027] The platy talc used in the present invention may or may not be surface-treated. For methods of surface-treating talc, see JP 2011-073902 A, the contents of which are incorporated herein by reference.

[0028] The platy talc is contained in an amount of 10 to 40% by mass when the total of the polyamide resin and the platy talc is taken as 100% by mass. The content of the platy talc is preferably 15% by mass or more, more preferably 18% by mass or more, even more preferably 21% by mass or more, and even more preferably 25% by mass or more, and may be 38% by mass or less, 35% by mass or less, or 33% by mass or less. In this embodiment, the composition as a raw material may contain only one type of platy talc, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0029] In this embodiment, the raw material composition has a bulk density of 0.30 g / cm 3 In the present embodiment, the raw materials of the resin composition may contain platy talc having a bulk specific gravity of less than 0.30 g / cm. 3 The proportion of platy talc that is less than 0.30 g / cm 3 It is preferably 10% by mass or less of the platy talc, more preferably 5% by mass or less, even more preferably 3% by mass or less, and may be 1% by mass or less.

[0030] In this embodiment, the total of the polyamide resin and platy talc in the raw material composition preferably accounts for 90% by mass or more, and may even be 95% by mass or more, or 98% by mass or more. Furthermore, the total of the polyamide resin and platy talc in the raw material composition is preferably 100% by mass or less.

[0031] <<Other ingredients>> In this embodiment, the composition as a raw material may contain other components in addition to those described above. Examples of other components include thermoplastic resins other than polyamide resins, release agents, plasticizers, inorganic fillers other than talc, titanium oxide, antioxidants, hydrolysis resistance improvers, matting agents, UV absorbers, nucleating agents other than talc, plasticizers, dispersants, antistatic agents, coloring inhibitors, antigelling agents, colorants, etc. For details of these components, please refer to paragraphs

[0130] to

[0155] of Japanese Patent No. 4,894,982, the contents of which are incorporated herein by reference.

[0032] <Melt mixing> In this embodiment, the polyamide resin, which is the raw material of the resin composition, has a bulk density of 0.30 g / cm 3 The method includes melt-kneading the above-mentioned platy talc and any other components blended as required, and extruding the mixture in an extruder. By using such a method, a large amount of talc can be introduced into the extruder, the residence time of the resin in the extruder can be reduced, and a resin composition can be obtained in which the increase in YI value is small (ΔYI is small) compared to the raw material polyamide resin.

[0033] In this embodiment, it is preferable to supply the platy talc to the extruder by side feeding. Side feeding allows for more efficient supply of talc than top feeding, and tends to further improve the discharge rate. Furthermore, in this embodiment, it is preferable to side feed the platy talc in two or more separate batches. By supplying the platy talc to the extruder by side feeding in two or more separate batches, the platy talc can be melt-kneaded with the polyamide resin more efficiently, and the discharge rate of the resin composition can be increased. Furthermore, since the residence time of the polyamide resin is shortened, the YI value of the resulting resin composition can be lowered. There is no particular upper limit on the number of side feeds, but it is usually 5 or less, and may be 5 or less, 4 or less, or 3 or less.

[0034] In this embodiment, the ratio Q / Ns calculated from the extruder's output rate Q and rotation speed Ns can be set to 0.1 to 0.4. Here, the output rate Q is expressed in kg / hour, and the rotation speed Ns is expressed in rpm. By setting Q / Ns to the lower limit or higher, heat generation due to shear and cracking of the talc are reduced, the YI value of the resulting resin composition tends to be lower, and the barrier properties tend to be more excellent. Furthermore, by setting Q / Ns to the upper limit or lower, the residence time is shortened, and the YI value of the resulting resin composition tends to be lower. The Q / Ns is preferably 0.14 or more, more preferably 0.15 or more, and even more preferably 0.16 or more. The upper limit of the Q / Ns is preferably 0.38 or less, and more preferably 0.35 or less.

[0035] In this embodiment, the temperature of the resin composition when it is extruded from the extruder (resin temperature) is preferably 280 to 380°C. By setting the resin temperature to the lower limit or higher, it is possible to improve the dischargeability and shorten the residence time, thereby lowering the YI value of the resulting resin composition. By setting the resin temperature to the upper limit or lower, it is possible to more effectively suppress thermal degradation of the polyamide resin. The lower limit of the resin temperature is preferably 290° C. or higher, more preferably 310° C. or higher, even more preferably 325° C. or higher, even more preferably 330° C. or higher, and even more preferably 340° C. or higher. The upper limit of the resin temperature is preferably 375° C. or lower, more preferably 370° C. or lower, and even more preferably 365° C. or lower.

[0036] <Physical properties> The resin composition obtained by the manufacturing method of this embodiment preferably has excellent oxygen barrier properties. Specifically, the oxygen permeability coefficient is preferably 0.1 cc·mm / (m 2 ·day·atm) or less, and 0.08cc·mm / (m 2 ·day·atm) or less is more preferable, and 0.06cc·mm / (m 2 ·day·atm) or less is more preferable. The lower limit is 0 cc·mm / (m 2 ·day·atm) is ideal, but 0.001cc·mm / (m 2 ·day·atm) or more is practical. The oxygen permeability coefficient is measured as described in the Examples section below.

[0037] The resin composition obtained by the production method of this embodiment preferably has a smaller YI value (ΔYI) compared to the YI value of the raw material polyamide resin. Specifically, ΔYI is preferably 27 or less, more preferably 25 or less, and even more preferably 23 or less. The lower limit of the ΔYI is ideally 0, but practically 10 or more. The raw material polyamide resin is intended to include not only the polyamide resin itself, but also additives used in the synthesis of the polyamide resin, decomposition products of the additives, and cyclic monomers derived from the raw material monomers of the polyamide resin. ΔYI is measured as described in the Examples below.

[0038] <Molded products> The resin composition obtained by the production method of this embodiment may be in the form of pellets, a film, or other molded articles, and is preferably in the form of pellets. The pellets are then molded into various molded articles by a known molding method such as injection molding. The molded article may be formed solely from the resin composition obtained by the manufacturing method of this embodiment, or may be used as a molded article combined with other components. Furthermore, the molded article does not necessarily have to be a final product, but may be a component constituting a part of a final molded article. The molded article can be used as at least a part of a packaging material, or as at least a part of a container such as a bottle, tray, cup, tube, or various pouches, including flat bags and stand-up pouches. The molded article, for example, packaging material or container, is suitable for storing and preserving various items. Examples of such items include beverages, seasonings, grains, liquid and solid products requiring aseptic filling or heat sterilization, chemicals, liquid daily necessities, pharmaceuticals, semiconductor integrated circuits, and electronic devices. For details, please refer to paragraphs 0032 to 0035 of JP 2011-037199 A, the contents of which are incorporated herein by reference. Specific examples of molded products include direct blow molded products, compressed air vacuum molded products, paper laminates, paper / barrier layer / barrier layer laminates, and films for film lamination of resin foam multilayer bodies. [Example]

[0039] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0040] raw material <Polyamide resin> MXD6I(6): It was synthesized according to the following synthesis example. It is a polyamide resin composed of metaxylylenediamine, adipic acid and isophthalic acid, and the molar ratio of adipic acid to isophthalic acid is 94:6. <<Synthesis of MXD6I(6)>> Into a 50 L jacketed reaction kettle equipped with a stirrer, a partial condenser, a cooler, a thermometer, a dropping funnel and a nitrogen gas inlet tube, 15.1 kg of adipic acid and 1.1 kg of isophthalic acid ,Next 13.9 g of sodium phosphite monohydrate and 7.2 g of sodium acetate were charged, and after sufficient nitrogen substitution, the temperature was raised to 180 °C under a small amount of nitrogen flow. After adipic acid was uniformly melted, while stirring the system, metaxylylenediamine 14.9 kg was added dropwise over 110 minutes. During this period, the internal temperature was continuously raised to 245 °C. The water generated by polycondensation was removed outside the system through the partial condenser and the cooler. After the dropwise addition of metaxylylenediamine was completed, the internal temperature was further raised to 260 °C, and after reacting for 1 hour, the polymer was taken out as a strand from the nozzle at the bottom of the reaction kettle, cooled with water and pelletized to obtain the polymer. Next, the polymer obtained by the above operation was put into a 250 L rotary tumbler equipped with a heating jacket, a nitrogen gas inlet tube and a vacuum line. While rotating, the pressure inside the system was reduced, and then the operation of returning to normal pressure with nitrogen with a purity of 99% by volume or more was performed 3 times. Then, the temperature inside the system was raised to 140 °C under nitrogen flow. Next, the pressure inside the system was reduced, and the temperature was continuously raised to 200 °C. After holding at 200 °C for 30 minutes, nitrogen was introduced to return the pressure inside the system to normal pressure, and then it was cooled to obtain a polyamide resin (MXD6I(6)). The oxygen permeability coefficient of the obtained polyamide resin (MXD6I(6)) was 0.07 cc·mm / (m 2 ·day·atm) at 23 °C and a relative humidity of 60%.

[0041] MXD6I(50): It was synthesized according to the following synthesis example. It is a polyamide resin composed of metaxylylenediamine, adipic acid and isophthalic acid, and the molar ratio of adipic acid to isophthalic acid is 50:50 <<Synthesis of MXD6I(50)>> Into a 50 L jacketed reaction kettle equipped with a stirrer, a partial condenser, a cooler, a thermometer, a dropping funnel, and a nitrogen gas inlet tube, 7.5 kg of adipic acid, 8.5 kg of isophthalic acid, 9.3 g of sodium hypophosphite monohydrate, and 4.8 g of sodium acetate were charged. After sufficient nitrogen substitution, the temperature was raised to 180 °C under a small amount of nitrogen flow, and adipic acid and isophthalic acid were uniformly melted. Then, while stirring the system, 13.9 kg of metaxylenediamine was dropped into it over 170 minutes. During this period, the internal temperature was continuously raised to 265 °C. The water generated by polycondensation was removed outside the system through the partial condenser and the cooler. After the dropping of metaxylenediamine was completed, the internal temperature was further raised to 270 °C, and the reaction was continued for 10 minutes. Then, the polymer was taken out as a strand from the nozzle at the bottom of the reaction kettle, water-cooled, and pelletized to obtain the polymer. Next, the polymer obtained by the above operation was put into a 250 L rotary tumbler equipped with a heating jacket, a nitrogen gas inlet tube, and a vacuum line. While rotating, the pressure inside the system was reduced, and then the operation of returning to normal pressure with nitrogen having a purity of 99 vol% or more was performed three times. Then, the temperature inside the system was raised to 115 °C under nitrogen flow. Next, the pressure inside the system was reduced and held at 115 °C for 24 hours. After introducing nitrogen to return the pressure inside the system to normal pressure, it was cooled to obtain a polyamide resin (MXD6I(50)). The oxygen permeability coefficient of the polyamide resin (MXD6I(50)) was 0.08 cc·mm / (m 2 ·day·atm) at 23 °C and a relative humidity of 60%.

[0042] MXD6: Synthesized according to the following synthesis example. <<Synthesis of MXD6>> A 50-L jacketed reactor equipped with a stirrer, partial condenser, condenser, thermometer, dropping tank, and nitrogen gas inlet tube was charged with 15 kg of adipic acid, 0.4 g of sodium hypophosphite monohydrate, and 0.2 g of sodium acetate. The reactor was thoroughly purged with nitrogen and heated to 180°C under a small nitrogen stream until the adipic acid was uniformly melted. Then, 13.9 kg of meta-xylylenediamine was added dropwise over 110 minutes while stirring. During this time, the internal temperature was continuously raised to 245°C. Water produced by polycondensation was removed from the system via the partial condenser and condenser. After the dropwise addition of meta-xylylenediamine, the internal temperature was further raised to 260°C. The reaction was continued for 1 hour, after which the polymer was removed as strands from a nozzle at the bottom of the reactor, cooled with water, and pelletized to obtain the polymer. Next, the polymer obtained by the above procedure was placed in a 250 L rotary tumbler equipped with a heating jacket, a nitrogen gas inlet tube, and a vacuum line. While rotating, the system was reduced in pressure, and then returned to normal pressure with nitrogen of 99% or higher by volume. This procedure was repeated three times. The system was then heated to 140°C under a nitrogen flow. The system was then reduced in pressure and further heated continuously to 200°C. After holding at 200°C for 30 minutes, nitrogen was introduced to return the system to normal pressure, and the system was then cooled to obtain polyamide resin (MXD6). The oxygen permeability of the obtained polyamide resin (MXD6) was 0.09 cc·mm / (m 2 ·day·atm).

[0043] <Talc> PAOG-2: Plate-shaped talc, manufactured by Nippon Talc Co., Ltd., high aspect ratio talc series, median diameter D 50 Particle size 7μm PAOG-2comp: PAOG-2 compressed and processed. Produced according to the following production example. P-2: Plate-shaped talc, manufactured by Nippon Talc Co., Ltd., median diameter D 50 Particle size 7μm P-2comp: Compressed P-2. Produced according to the following production example. The bulk density of talc was measured in accordance with the static method of JIS K5101. Specifically, talc was charged into the receiver attached to the bulk density measuring device until it overflowed. The talc that had overflowed from the inlet of the receiver to the upper part was scraped off with a spatula, the weight of the talc in the receiver was measured, and the bulk specific gravity was calculated using the following formula. Bulk specific gravity = weight of talc in the receiver (g) / capacity of the receiver (mL).

[0044] <<Production Example of PAOG-2comp>> Plate-shaped talc PAOG-2 was degassed using a degassing device (manufactured by Kurimoto Iron & Steel Co., Ltd., Kriback KV-200), and the degassed plate-shaped talc was sent to a compression device (manufactured by Kurimoto Iron & Steel Co., Ltd., Roller Compactor RCP400W) for compression to obtain PAOG-2comp.

[0045] <<Production Example of P-2comp>> Plate-shaped talc P-2 was degassed using a degassing device (manufactured by Kurimoto Iron & Steel Co., Ltd., Kriback KV-200), and the degassed plate-shaped talc was sent to a compression device (manufactured by Kurimoto Iron & Steel Co., Ltd., Roller Compactor RCP400W) for compression to obtain P-2comp.

[0046] Example 1 Using a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., TEM26SX), the temperature of the twin-screw extruder was set to 260 °C, and pellets of the polyamide resin and talc powder shown in Table 1 were melt-kneaded to obtain pellets. The pellets of the polyamide resin and the talc powder were filled in different hoppers and supplied from the side feeder so as to have the composition (mass %) shown in Table 1. The conditions of the compound were as shown in Table 1. The obtained pellets were vacuum dried at 120 °C for 6 hours to obtain a resin composition (pellets).

[0047] Using a single-screw extruder with a T-die (manufactured by Plastic Engineering Laboratory, PTM-25) and a cooling roll, the extruder was set to 26 °C, and the temperature of the first cooling roll was set to 80 °C. The polyamide resin and plate-shaped talc were blended so as to have the composition shown in Table 1. Melted and kneaded The resin composition was Single axis with T die [[ID=​The obtained pellets or films were used to conduct the following evaluations.

[0048] <Measurement of Ash Content> The obtained resin composition was placed in a crucible and heated in a heating furnace at 600 °C for 12 hours to be ashed, and the ash content (mass %) of the residue was determined.

[0049] <YI Value> The YI value of the raw material polyamide resin (YI of the resin) and the YI value after drying the pellets obtained above at 120 °C for 6 hours (YI after drying) were measured by the reflection method using a color difference meter based on JIS Z 8722. The color difference meter used was ZE - 2000 (manufactured by Nippon Denshoku Industries Co., Ltd., halogen lamp light source of 12V 20W). The pellets were filled in a cell container with a diameter of 30 mm and measured. The average value obtained from 4 measurements was taken. Also, the difference between the YI of the resin and the YI after drying was defined as ΔYI.

[0050] <Moisture Content after Drying (KF Moisture after Drying)> The moisture content was measured using a Karl Fischer moisture meter according to the method based on ISO15512. The unit was shown as %. The Karl Fischer moisture meter used was the CA - 200 type, a micro - moisture measuring device with a coulometric titration method, manufactured by Nitto Seiko Analytic (former Mitsubishi Chemical Analytic).

[0051] <Melt Flow Rate (MFR)> According to JIS K7210, for crystalline resins, the measurement was carried out at a temperature of (melting point + 15 °C), and for amorphous resins, at a temperature of 260 °C, under a load of 1.2 kgf. MFR can be used as an index of molding fluidity, and a higher MFR value indicates higher fluidity. The melt indexer used was C5059D manufactured by Toyo Seiki Seisaku - sho, Ltd. <Measurement of Melting Point and Crystallinity / Amorphousness> By measuring the differential scanning calorimetry (DSC), the melting point (Tm) of the synthesized polyamide resin was measured, and also the change in melting enthalpy (ΔH) was measured to determine the crystallinity / amorphousness. The DSC measurements were carried out in accordance with JIS K7121 and K7122. Specifically, a differential scanning calorimeter was used, and the synthesized polyamide resin was crushed and placed in the measurement pan of the differential scanning calorimeter, and the temperature was raised to 330°C at a heating rate of 10°C / min under a nitrogen atmosphere. Polyamide resins for which the enthalpy change ΔH (unit: J / g) upon melting was 5 J / g or less, or for which no melting peak was observed even when heated to 330°C, were defined as amorphous resins, and other polyamide resins were defined as crystalline resins. Similarly, the synthesized polyamide resin was placed in a measurement pan and heated under a nitrogen atmosphere at a rate of 10°C / min to (the temperature thought to be the melting point + 20°C) for the crystalline resin and to 260°C for the amorphous resin. Immediately after the heating was completed, the measurement pan was removed and pressed against dry ice to rapidly cool. Measurements were then performed. The measurement conditions were a heating rate of 10°C / min, with the crystalline resin heated to (the temperature thought to be the melting point + 20°C) and the amorphous resin heated to 260°C, and the melting point (Tm) (unit: °C) was determined. The differential scanning calorimeter used was a "DSC-60" manufactured by Shimadzu Corporation.

[0052] <Oxygen transmission rate (OTR)> The OTR was measured using a film formed to a thickness of 50 μm. That is, OTR of polyamide resin was carried out using a film obtained by melt-extruding polyamide resin pellets from a T-die in an extruder to obtain a film having a thickness of 50 μm and a width of 100 mm. The oxygen transmission rates (OTR) of the films formed from the resin pellets and the films obtained from the resin compositions were measured at 23°C and a relative humidity of 60% in accordance with ASTM D3985 using an oxygen transmission coefficient measuring device. The unit pressure of the OTR was 1 atm, and the unit transmission time was 24 hours. The oxygen permeability measuring device used was a product of MOCON, product name: "OX-TRAN (registered trademark) 2 / 21".

[0053] <Aspect ratio of talc in resin composition after extrusion> The aspect ratio of the talc in the resin composition after extrusion was determined as R0 and R1 of the platy talc in the film obtained above. 45 and R 90 Evaluate R0, R 45 and R 90 The largest value among these was used. < <R0、R 45 and R 90 Measurement >> After laminating aluminum foil on the film with Araldite, the film was cut perpendicular to the film surface, and the cross section was cut by ion milling (this cross section is called cross section A). The cutting direction at this time was set to 0°. During ion milling, the argon ion beam was irradiated from the aluminum foil toward the film. Cross-sectional ion milling conditions Equipment: Hitachi IM-4000 Conditions: Accelerating voltage 4kV Discharge voltage 1.5kV Mode C4 Processing time: 4 hours Protrusion amount 30μm The obtained sample was treated with tungsten for 60 seconds for electrical conductivity, and then cross section A was subjected to backscattered electron image observation using a scanning electron microscope (SEM observation). A region of 30 μm length × 40 μm width (area 1200 μm) was observed. 2 For each particle of platy talc present in the sample, two parallel tangent lines were drawn at both ends of the longest part, and the distance between the tangent lines was defined as the maximum length L. Next, a line perpendicular to the two tangent lines was drawn across each particle, and the length of the longest line segment that overlapped with the particle was measured, and this length was defined as the minimum width d. The ratio of maximum length to minimum width (L / d) was measured for each particle. The same procedure was repeated twice, and the average of the maximum length to minimum width ratios (L / d) of the top 1% (largest values) of the distribution of the obtained maximum length to minimum width ratios (L / d) was defined as R0. Next, a cross section perpendicular to the film surface and at an angle of 45° to the cross section A was measured in the same manner as above, with a length of 1200 μm. 2 The average value of the top 1% of the ratios of the maximum length and minimum width of each plate-shaped talc contained in the area (R 45 ) was sought. Furthermore, a cross section perpendicular to the film surface and at an angle of 90° to the cross section A was measured in the same manner as above, and the cross section was then measured to obtain a cross section of 1200 μm. 2 The average value of the top 1% of the ratios of the maximum length and minimum width of each plate-shaped talc contained in the area (R 90 ) was measured.

[0054] The conditions for SEM observation are as follows: Equipment: Hitachi SU8020 Conditions: Accelerating voltage 1kV Probe current 20μA, Normal Observation magnification: 3000x Working distance: 3 mm No tilt Conductively treated tungsten for 60 seconds

[0055] Examples 2 to 9, Comparative Examples 1 and 2 In Example 1, the changes were made as shown in Table 1 or Table 2, and the other procedures were the same.

[0056] [Table 1]

[0057] [Table 2]

[0058] In the above table, "SF" in the addition method refers to side feed, and "SF 1 location" means that the platy talc was supplied by one side feed. In the table above, mesh is an indicator of the size of the filter openings, and refers to the number of openings per inch. In the above table, the resin temperature means the temperature of the resin composition when it is extruded from the extruder, and is the temperature of the resin composition measured with a contact thermometer immediately after it is discharged from the die. As is clear from the above results, the resin composition produced by the manufacturing method of the present invention had a small difference (ΔYI) between the YI value of the raw material polyamide resin alone and the YI value of the resin composition after adding talc. In contrast, the bulk density of plate-shaped talc is 0.30 g / cm 3 When the temperature was less than 100°C, the ΔYI was large.

Claims

1. Polyamide resin and a bulk density of 0.30 g / cm ３ and the platy talc described above in a proportion such that the platy talc accounts for 10 to 40% by mass when the total of the polyamide resin and the platy talc is 100% by mass, and the resulting mixture is extruded using an extruder, the total amount of the polyamide resin and the platy talc in the raw materials fed into the extruder is 90% by mass or more, The bulk density of the platy talc before being charged into the extruder is 0.30 g / cm ３ That's all, The method for producing a resin composition, wherein the aspect ratio of the platy talc before being fed into the extruder is greater than 18.

2. The method for producing a resin composition according to claim 1 , comprising supplying the platy talc to an extruder by a side feed.

3. The method for producing a resin composition according to claim 1 , comprising supplying the platy talc to an extruder by side feeding in two or more batches.

4. The method for producing a resin composition according to any one of claims 1 to 3, wherein the Q / Ns of the extruder is 0.1 to 0.4; where Q means a discharge rate (unit: kg / hour) and Ns means a rotation speed (unit: rpm).

5. The method for producing a resin composition according to any one of claims 1 to 4, wherein the temperature of the resin composition when extruded from the extruder is 280 to 380°C.

6. The method for producing a resin composition according to any one of claims 1 to 5, wherein the polyamide resin is a semi-aromatic polyamide resin.

7. The polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, and 50 mol% or more of the diamine-derived structural units are derived from xylylenediamine, and 30 mol% or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms. The method for producing a resin composition according to any one of claims 1 to 5.

8. The method for producing a resin composition according to any one of claims 1 to 5, wherein the polyamide resin is composed of diamine-derived structural units and dicarboxylic acid-derived structural units, and 50 mol% or more of the diamine-derived structural units are derived from xylylenediamine, 30 to 99 mol% of the dicarboxylic acid-derived structural units are derived from an α,ω-linear dicarboxylic acid having 4 to 15 carbon atoms, and 1 to 70 mol% are derived from isophthalic acid.

9. The polyamide resin has an oxygen permeability coefficient of 0.1 cc mm / (m) measured in accordance with ASTM D3985 under an atmosphere of 23°C and 60% relative humidity. 2 The method for producing a resin composition according to any one of claims 1 to 8, wherein the viscosity is 1000 kJ / min or less.

10. The method for producing a resin composition according to any one of claims 1 to 9, wherein the resin composition is in the form of pellets.

11. A raw material composition used to carry out the method for producing a resin composition according to any one of claims 1 to 10, comprising: Polyamide resin and a bulk density of 0.30 g / cm ３ The platy talc is the platy talc accounts for 10 to 40% by mass when the total of the polyamide resin and the platy talc is 100% by mass; In the raw material composition, the polyamide resin and the platy talc account for 90 mass% or more in total, and the platy talc has an aspect ratio of more than 18.

12. Pellets obtained by melt-kneading the raw material composition according to claim 11 and extruding the mixture in an extruder.

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