WO2007026865A1 - Polyamide, polyamide composition, and molded polyamide - Google Patents

Abstract

A polyamide which is either a polyamide comprising, as the main structural units, units derived from an aliphatic dicarboxylic acid and an aromatic diamine or a polyamide comprising, as the main structural units, units derived from an aromatic dicarboxylic acid and an aliphatic diamine, characterized in that when the polyamide is dissolved in a solvent for 31P-NMR spectroscopy and the resultant solution is subjected to structure analysis after trifluoroacetic acid is added thereto, then the content of phosphorus atoms (P1) derived from a phosphorus compound of a specific structure detected is 10 ppm or higher. Features of the polyamide reside in that the polyamide has satisfactory thermal stability during drying or molding, that the polyamide hence does not deteriorate in color tone and is less apt to generate gel particles or other undesirable substances, and that these properties do not particularly deteriorate even when a recovered article of the polymer is mixed and used. The polyamide has excellent productivity in molding. Also provided are a polyamide composition containing the polyamide and a molded polyamide obtained from the polyamide composition.

Description

 Specification

 Polyamide, polyamide composition and polyamide molded body

 Technical field

 [0001] The present invention relates to a molded article such as a film or sheet, a hollow molded container such as a beverage bottle, a polyamide suitably used as a material for an engineering plastics material, a polyamide composition comprising the same, and a The present invention relates to a polyamide molded body obtained by using the same. In addition, when they are dried or molded, they have good thermal stability, so the color tone does not deteriorate, the generation of foreign substances such as gels is small, and the recovered products (sometimes referred to as recycled products). The present invention relates to a polyamide excellent in productivity at the time of molding, a polyamide composition comprising the same, and a polyamide molded article obtained by using the same, characterized in that these properties are not particularly bad even when used in a mixture.

 Background art

 [0002] Polyamides are widely used in applications such as hollow molded containers, films, sheet packaging materials, engineering plastics, and fibers because of their excellent physical and mechanical properties. Typical examples are aliphatic polyamides such as nylon 6 and nylon 66. Besides these, aromatic diamines such as paraxylylenediamine (PXDA) and metaxylylenediamine (MXDA), and fragrances such as terephthalic acid. A number of polyamides that use a dicarboxylic acid as a raw material to achieve reduced water absorption and improved elastic modulus are also known.

 [0003] Polyamide is relatively unstable to heat than polyester or the like, and may cause gelling or yellowing due to thermal degradation or thermal oxidation degradation.

[0004] As a method for suppressing the thermal degradation of polyamide, a method of adding a phosphonic acid compound or a phosphite compound and an alkali metal to the polyamide has been proposed (for example, see Patent Document 1).

[0005] Further, as a method for suppressing the thermal degradation of polyamide, (a) a phosphinic acid compound, a phosphonous acid compound, a phosphonic acid compound or a phosphorous acid compound in (b) A method of blending an alkali metal with (c) phenylenediamine and Z or a derivative thereof has been proposed (for example, see Patent Document 2). [0006] As a method of preventing thermal deterioration in the system below the melting point of polyamide and without oxygen, pyrophosphite, amidy compound of organic phosphinic acid, barium of mono or diester of phosphorous acid A method of adding a salt, a copper salt of a mono- or diester of orthophosphoric acid, etc. has been proposed (see, for example, Patent Documents 3, 4, 5, and 6).

 [0007] In addition, as a countermeasure to prevent the formation of a gelled product of metaxylylenediamine and adipic acid, a lubricant, an organophosphorus stabilizer, a hindered phenol compound, and a hindered amine compound are selected. At least one or more of these are studied by adding 0.0005-0. 5 parts by weight (for example, see Patent Document 7).

 [0008] In addition, a method of polymerizing a polyamide mainly composed of terephthalic acid and hexamethylenediamine in the presence of hypophosphite (see, for example, Patent Document 8), adipic acid, terephthalic acid, and isophthalic acid A method for polymerizing hexamethylenediamine in the presence of hypophosphite (see, for example, Patent Document 9) is disclosed.

 [0009] Although these technologies are effective in preventing gelation of polyamide, coloring may cause gelation depending on molding conditions such as drying conditions, molding temperature, and melting time, which are not satisfactory. In addition, the occurrence of foreign matters, abnormal appearance of the molded product, or poor transparency due to this has occurred, and a solution is desired.

 [0010] In addition, the terminal amino group concentration of the polyamide composition is suppressed as a polyamide-based composition that suppresses an increase in melt viscosity at the time of melting of a polyamide-based composition composed of two or more polyamides and has excellent flowability and moldability. There have been proposed polyamide-based compositions in which the difference in terminal carboxyl group concentration is regulated, and polyamide-based yarns and compositions in which the relationship between these differences and the phosphorus atom concentration in the polyamide yarns and compositions is regulated (for example, patents). (Ref. 10, 11). However, these techniques are insufficient in terms of the stability of the melt viscosity and the prevention of coloration when staying at a higher temperature or for a long time, and a solution is desired.

 Patent Document 1: JP-A-49-45960

 Patent Document 2: JP-A-49-53945

 Patent Document 3: Japanese Patent Publication No. 45-11836

 Patent Document 4: Japanese Patent Publication No. 45-35667

Patent Document 5: Japanese Patent Publication No. 45-12986 Patent Document 6: Japanese Patent Publication No. 46-38351

 Patent Document 7: Japanese Patent Laid-Open No. 2001-164109

 Patent Document 8: JP-A-5-43681

 Patent Document 9: Japanese Patent Laid-Open No. 3-126725

 Patent Document 10: JP-A-6-220320

 Patent Document 11: Japanese Patent Laid-Open No. 7-247422

 Brief Description of Drawings

 [0011] FIG. 1 is a plan view of a stepped molded plate used in an embodiment of the present invention (the symbols are as follows. A: Part A of the stepped molded plate, B: Stepped molded plate) Part B, C: Stepped plate forming part C, D: Stepped plate forming part D, E: Stepped plate forming part E, F: Stepped plate forming part F, G: Stepped molded plate gate)

 [Figure 2] Side view of the stepped molded plate of Figure 1

 Disclosure of the invention

 Problems to be solved by the invention

[0012] The present invention solves the above-mentioned problems of the prior art and has good thermal stability at the time of drying and molding, so that the color tone does not deteriorate and the generation of foreign matters such as gel-like substances is small. On the other hand, a polyamide excellent in productivity at the time of molding and a polyamide composition comprising the same, characterized in that these characteristics are not particularly deteriorated even when a collected product (sometimes referred to as a recycled product) is mixed. In addition, an object of the present invention is to provide a polyamide molded article obtained using the same.

 Means for solving the problem

 [0013] The inventors of the present invention have arrived at the present invention as a result of intensive studies to achieve the above object. That is, the present invention is as follows.

[1] A polyamide whose main constituent unit is a unit derived from an aliphatic dicarboxylic acid and an aromatic diamine, or a unit derived from an aromatic dicarboxylic acid and an aliphatic diamine as a main constituent unit. When the polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added, and then structural analysis is performed, the phosphor is detected with the structure of the following structural formula (formula 1). A polyamide containing a compound and having a phosphorus atom content (P1) derived from the phosphorus compound of 10 ppm or more.

[0015] [Chemical 1]

(Equation 1)

[Wherein R and R are hydrogen, alkyl group, aryl group, cycloalkyl group or aryl group.

 1 2

 Rualkyl group, X is hydrogen)

[2] When the polyamide is dissolved in a ³¹ P-NMR measurement solvent and trifluoroacetic acid is added and then subjected to structural analysis, it contains a phosphorus compound detected by the structure of the following structural formula (formula 2), and The polyamide according to [1], wherein the phosphorus atom content (P2) derived from the phosphorus compound represented by the structural formula (Formula 2) is 30 ppm or more.

 [0018] [Chemical 2]

(Formula 2)

[0019] (where R is hydrogen, an alkyl group, an aryl group, a cycloalkyl group, or an aryl alkyl group.

 Three

 R group, X and X are hydrogen)

 twenty three

 [0020] [3] The polyamide according to [1] or [2], wherein the polyamide contains at least 50 mol% of a structural unit derived from metaxylylenediamine and a dicarboxylic acid in the molecular chain. The polyamide according to the above.

 [4] The polyamide according to [1] or [2], wherein the polyamide contains at least 50 mol% of a structural unit derived from metaxylylenediamine and adipic acid in the molecular chain. The polyamide according to any one of the above.

 [0022] [5] Polyamide chip color b value (Co-b) force The polyamide according to any one of [1] to [4], wherein the following formula (1) is satisfied.

[0023]-5 <(Co-b) <10 (1) [0024] [6] A polyamide composition comprising the polyamide according to any one of [1] to [5] and an aliphatic polyamide as main components.

 [0025] [7] 100 parts by weight of aliphatic polyamide and the polyamide according to any one of [1] to [5] 0.5 to 3

A polyamide composition mainly composed of 0 part by weight.

[0026] [8] 100 parts by weight of the polyamide according to any one of [1] to [5] and aliphatic polyamide 0.5 to 1

A polyamide composition mainly comprising 00 parts by weight.

[9] The polyamide composition as described in any one of [6] to [8], wherein the aliphatic polyamide is nylon 6.

 [0028] [10] The polyamide composition according to any one of [6] to [9], wherein the polyamide composition contains a recovered product of a polyamide molded product having a high strength.

[11] The polyamide composition according to any one of [6] to [10], wherein the water content is 200 to 2000 ppm.

[12] [12] A polyamide molded article obtained by molding the polyamide composition according to any one of [6] to [11].

 [0031] [13] A polyamide molded article having at least one layer formed by melt-molding the polyamide composition according to any one of [6] to [11].

[14] A polyamide molded article according to [12] or [13], which is a sheet-like article or a stretched film obtained by stretching the sheet article in at least one direction. The invention's effect

 [0033] Since the polyamide of the present invention has good thermal stability and thermal acidity stability during drying and molding, it has excellent color tone and is difficult to be colored in the molding process. Is used as a material for molded products such as films and sheets, hollow molded containers such as beverage bottles, and engineering plastics. Can be manufactured. Further, it can be used as a molded product such as a film or a sheet as a composition with an aliphatic polyamide.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0034] Hereinafter, embodiments of the polyamide of the present invention and a powerful polyamide composition will be described in detail. The polyamide of the present invention is a polyamide having a unit derived from an aliphatic dicarboxylic acid and an aromatic diamine as a main structural unit, or a polyamide having a unit derived from an aromatic dicarboxylic acid and an aliphatic diamine as a main structural unit. In the case where the polyamide is dissolved in a ³¹ P-NMR measurement solvent and subjected to structural analysis after adding trifluoroacetic acid, the phosphorus atom content derived from the phosphorus compound detected by the structure of the following structural formula (formula 1) ( P1) is a polyamide characterized in that it is lOppm or more.

[0035] [Chemical 3]

(Formula 1)

[0036] (wherein R and R are hydrogen, an alkyl group, an aryl group, a cycloalkyl group, or an aryl group.

 1 2

 Rualkyl group, X is hydrogen)

[0037] When the polyamide is dissolved in a ³¹ P-NMR measurement solvent and analyzed by structure after adding trifluoroacetic acid, the phosphorus atom content derived from the phosphorus compound detected by the structure of the structural formula (Formula 1) (P1) Is more preferably 15 ppm or more, and still more preferably 20 ppm or more. If the P1 content is less than 10 ppm, the heat stability of the polyamide is poor.Therefore, only molded products that are intensely colored when heated in the presence of oxygen, such as hot-air drying, or when melt-molded are colored yellow. In addition, a gel-like material is likely to be generated, and the resulting molded body such as a film has a large amount of foreign matters and fish eyes, which is a problem. In particular, when oxygen is present in the atmosphere during molding, the quality deterioration of the molded body as described above becomes remarkable.

 The upper limit of P1 is preferably 350 ppm or less, more preferably 320 ppm or less, and even more preferably 300 ppm or less. If the content of P1 exceeds 350 ppm, it is possible to increase the molecular weight in the subsequent process and cause precipitation as a foreign substance, which is not preferable as a cause of filter clogging.

[0038] Further, when the polyamide of the present invention is dissolved in a ³¹ P-NMR measurement solvent and subjected to structural analysis after adding trifluoroacetic acid, a phosphorus atom derived from a phosphorus compound detected by the structure of the following structural formula (formula 2) It is preferable that the content (P2) is 30ppm or more. [0039] [Chemical 4]

(Formula 2)

[0040] (where R is hydrogen, an alkyl group, an aryl group, a cycloalkyl group, or an aryl alkyl group.

 Three

 R group, X and X are hydrogen)

 twenty three

[0041] When the polyamide is dissolved in a ³¹ P-NMR measurement solvent and the structure is analyzed after adding trifluoroacetic acid, the phosphorus atom content derived from the phosphorus compound detected by the structure of the structural formula (Formula 2) (P2) Is more preferably 35 ppm or more, and still more preferably 40 ppm or more. Phosphorus compounds that have a phosphorus atom content (P1) of not less than lOppm detected in the structure of structural formula (Formula 1) in the polyamide and are detected in the structure of Formula (Formula 2) When the phosphorus atom content (P2) content is 30 ppm or more, the phosphorus atom content (P1) derived from the phosphorus compound detected in the structure of formula (Formula 1) only satisfies lOppm or more. Compared with the case, the thermal stability of the polyamide of the present invention is further improved.

 The upper limit of P2 is preferably 300 ppm or less, more preferably 270 ppm or less, and even more preferably 250 ppm or less. If the content of P2 exceeds 300 ppm, it is possible to increase the molecular weight in the subsequent process and cause precipitation as a foreign substance, which is not preferable as a cause of filter clogging.

[0042] In addition, for the measurement of the content of the phosphorus compound of the above structural formula in the polyamide, the structural analysis ³¹ P-NMR method of the phosphorus compound described later was used. Pl and P2 are contents relative to the weight of the polyamide.

 [0043] Further, in the polyamide composition comprising the above polyamide, it is not the total phosphorus content in the polyamide composition, but that the P1 and P2 satisfy the above relationship. This is important for thermal stability.

 [0044] (Polyamide of the present invention, partially aromatic polyamide)

The polyamide of the present invention is derived from a polyamide having a main constituent unit derived from an aliphatic dicarboxylic acid and an aromatic diamine or an aromatic dicarboxylic acid and an aliphatic diamine. Among the polyamides whose main constituent unit is a polyamide, a polyamide containing at least 50 mol%, preferably 60 mol% or more, particularly preferably 70 mol% or more in the molecular chain. In the following, the polyamide of the present invention may be referred to as a partially aromatic polyamide.

[0045] When the polyamide of the present invention is a polyamide whose main constituent unit is a unit derived from an aliphatic dicarboxylic acid and an aromatic diamine, the aromatic diamine component constituting such a polyamide may be a metaxylylene diamine. Min, paraxylylenediamine, para-bis (2-aminoethyl) benzene and the like.

 [0046] Further, as the aliphatic diamine component constituting the strong polyamide, there is an aliphatic diamine having 2 to 12 carbon atoms! Is a functional derivative thereof. The aliphatic diamine may be a linear aliphatic diamine or a branched chain aliphatic diamine! /. Specific examples of such straight chain aliphatic diamines include ethylene diamine, 1 methyl ethylene diamine, 1, 3 propylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, hepta. Examples include aliphatic diamines such as methylene diamine, otatamethylene diamine, nonamethylene diamine, decamethylene diamine, undecamethylene diamine, dodecamethylene diamine and the like.

 [0047] When the polyamide of the present invention is a polyamide whose main constituent unit is a unit derived from an aromatic dicarboxylic acid and an aliphatic diamine, the aromatic dicarboxylic acid component constituting the polyamide may be terephthalic acid. , Isophthalic acid, phthalic acid, 2,6 naphthalene dicarboxylic acid, diphenyl 4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid and functional derivatives thereof.

 [0048] Further, as the aliphatic dicarboxylic acid component constituting the strong polyamide, a linear aliphatic dicarboxylic acid having an alkylene group having 4 to 12 carbon atoms is preferred, and a linear aliphatic dicarboxylic acid is preferred. Especially preferred. Examples of such linear aliphatic dicarboxylic acids include adipic acid, sebacic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, undecanoic acid, undecadioic acid, dodecanedioic acid, dimer Examples thereof include acids and functional derivatives thereof.

[0049] Further, as the diamine component constituting the polyamide of the present invention, the aromatic diamine as described above is used. In addition to the aliphatic diamine, an alicyclic diamine can also be used. Examples of the alicyclic diamines include alicyclic diamines such as cyclohexane diamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, and the like.

 [0050] As the dicarboxylic acid component constituting the polyamide of the present invention, an alicyclic dicarboxylic acid can be used in addition to the aromatic dicarboxylic acid and the aliphatic dicarboxylic acid as described above. Examples of the alicyclic dicarboxylic acid include alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid.

 [0051] In addition to the above-mentioned diamine and dicarboxylic acid, ε-strength prolatatam and lautam latatam and other ratatams, aminocaproic acid and aminoundecanoic acid and other aminocarboxylic acids, and paraaminomethylbenzoic acid and other aromatic aminoaminocarboxylic acids An acid or the like can also be used as a copolymerization component. In particular, the use of ε-strength prolatatum is desirable.

 [0052] Further, as a copolymerization component, a polyether having at least one terminal amino group or a terminal carboxyl group and a molecular weight of 2000 to 20000, or an organic carboxylate of a polyether having the terminal amino group, or Polyester amino salts having terminal carboxyl groups can also be used. Specific examples include bis (aminopropyl) poly (ethylene oxide) (polyethylene glycol having a molecular weight of S2000 to 20000).

 [0053] Preferable examples of the partially aromatic polyamide of the present invention include metaxylylenediamine, or mixed xylylenediamine and aliphatic dicarboxylic acid containing metaxylylenediamine and 30% or less of the total amount of paraxylylenediamine. A metaxylylene group-containing polyamide containing in the molecular chain at least 50 mol%, more preferably 60 mol% or more, particularly preferably 70 mol% or more of a structural unit derived from an acid.

 [0054] Further, the partially aromatic polyamide of the present invention contains a structural unit derived from a polycarboxylic acid power of three or more bases such as trimellitic acid and pyromellitic acid within a substantially linear range. You may do it.

[0055] Examples of these polyamides include homopolymers such as polymetaxylylene adipamide, polymetaxylylene sebacamide, polymetaxylylene speramide, and the like, and metaxylylenediamine Z adipic acid Z isophthalic acid copolymer. Polymer, metaxylylene Z-paraxylylene adipamide copolymerization , Metaxylylene Z paraxylylene piperamide copolymer, metaxylylene Z paraxylylene zelamide copolymer, metaxylylene diamine Z adipic acid Z isophthalic acid Z ε Examples include acids, isophthalic acid, ω-amino caproic acid copolymers, and the like.

 [0056] In addition, as a preferred example of the partially aromatic polyamide of the present invention, as an example, as an aliphatic diamine and terephthalic acid or isophthalic acid power, at least one selected acid and a structural unit derived from the force are included in the molecular chain. Is a polyamide containing at least 50 mol%, more preferably 60 mol% or more, particularly preferably 70 mol% or more.

 [0057] Examples of these polyamides include polyhexamethylene terephthalamide, polyhexamethylene isophthalamide, hexamethylenediamine, terephthalic acid, isophthalic acid copolymer, polynonamethylene terephthalamide, polynonamethylene isophthalate. Examples thereof include amides, nonamethylene diamine, terephthalic acid, isophthalic acid copolymer, and nonamethylene diamine, terephthalic acid, didipic acid copolymer.

 [0058] In addition, other preferable examples of the partially aromatic polyamide of the present invention include ε-force prolatatum, laurac ratatatam, etc., in addition to aliphatic diamine and at least one acid selected from terephthalic acid or isophthalic acid. Selective power of aliphatic diamine and terephthalic acid or isophthalic acid obtained by using aminocarboxylic acids such as ratatams, aminocaproic acid and aminoundecanoic acid, and aromatic aminocarboxylic acids such as paraaminomethylbenzoic acid as copolymerization components Polyamide containing at least 50 mol% or more, more preferably 60 mol% or more, particularly preferably 70 mol% or more of a structural unit derived from at least one kind of acid in the molecular chain.

 [0059] Examples of these polyamides include hexamethylenediamine Ζ terephthalic acid ε ε-strength prolatam copolymer, hexamethylenediamine Ζ isophthalic acid Ζ ε-strength prolatatam copolymer, hexamethy Examples include diamamine, terephthalic acid, adipic acid, epsilon prolatatum copolymer.

[0060] The polyamide of the present invention was basically obtained by a conventionally known melt polycondensation method in the presence of water, a melt polycondensation method in the absence of water, or these melt polycondensation methods. Polyamide can be produced by a method such as solid phase polymerization. The melt polycondensation reaction is one stage It may be performed in multiple steps, or may be performed in multiple stages. These may be composed of a batch reactor or may be composed of a continuous reactor. In addition, the melt polycondensation step and the solid phase polymerization step may be operated continuously, or may be operated separately.

 [0061] Hereinafter, a preferred batch production method of the polyamide of the present invention will be described using a xylylene group-containing polyamide (Ny-MXD6) as an example, but the present invention is not limited thereto.

 That is, for example, a salt of metaxylylenediamine and adipic acid, an alkali metal-containing compound containing an alkali metal atom as a thermal decomposition inhibitor and an aqueous solution of a phosphorus compound are heated under pressure and normal pressure, It can be obtained from a method of polycondensation in a molten state while removing water and water generated by the polycondensation reaction.

 [0063] At this time, it is preferable that the tank for storing metaxylylenediamine and the tank for storing adipic acid are separately provided with a nitrogen gas atmosphere, and the oxygen concentration in the nitrogen gas atmosphere is 20 ppm or less. More preferred is 16 ppm, and most preferred is 15 ppm. When the oxygen content in the nitrogen gas atmosphere in the storage tank exceeds 20 ppm, the phosphorus atom content (P1) derived from the phosphorus compound represented by the structural formula (Formula 1) in the obtained polyamide is 10 ppm. In addition, the phosphorus atom content (P2) derived from the phosphorus compound represented by the structural formula (Formula 2) is less than 30 ppm, and the thermal stability of the polyamide is poor. In order to reduce the oxygen concentration in the atmosphere in the storage tank, an inert gas such as nitrogen is introduced into the tank, the air is replaced with nitrogen gas, and then an inert gas such as nitrogen gas is allowed to flow. This method is preferable. As a method for reducing the oxygen content in each raw material, it is preferable to publish an inert gas from the bottom of the can. As the inert gas used, it is preferred to use nitrogen gas having an oxygen content of 12 ppm or less, more preferably 1 ppm or less.

[0064] Also, in the step of preparing the salt of metaxylylenediamine and adipic acid by mixing the raw materials, various additives, and water, the oxygen concentration in the nitrogen gas atmosphere is 20 ppm or less, more preferably It is preferable to set it to 18 ppm or less, more preferably 16 ppm, and most preferably 15 ppm. Further, as a method of lowering the oxygen concentration, a method of publishing using an inert gas, for example, nitrogen gas, in the salt aqueous solution may be mentioned. Even in this process, when the oxygen content exceeds 20 ppm, the structural formula (formula 1) in the obtained polyamide is expressed. The phosphorus atom content (PI) derived from the phosphorus compound is less than lOppm, and the phosphorus atom content (P2) derived from the phosphorus compound represented by the structural formula (formula 2) is less than 30 ppm. The thermal stability of the amide will be poor.

 [0065] The temperature at which the salt is prepared is preferably 140 ° C or lower in order to suppress coloring due to thermal oxidative degradation and to suppress side reactions and thermal oxidative degradation reactions of additives. Preferably it is 130 ° C or lower, more preferably 120 ° C or lower, and most preferably 110 ° C or lower. The lower limit is preferably 30 ° C or higher, more preferably 40 ° C or higher, preferably at a temperature at which the salt does not solidify.

 [0066] Next, the prepared aqueous salt solution is transferred to a polymerization vessel and subjected to polycondensation. To evaporate the water in the aqueous salt solution, the unreacted substances are prevented from being scattered and oxygen is not allowed to enter the system. In order to prevent contamination, the temperature inside the can was gradually raised while applying a pressure of 0.5 to 1.5 MPa, the distilled water was removed from the system, and the temperature inside the can was adjusted to 230 ° C. The reaction time at this time is preferably 1 to 7 hours, more preferably 2 to 6 hours, and further preferably 3 to 5 hours. A sudden rise in temperature is not preferable because it causes a high molecular weight of the additive and a side reaction of the polymer, and causes a decrease in the thermal stability of the resin such as gel cake in the subsequent process. Thereafter, the internal pressure of the can was gradually released over 30 to 90 minutes and returned to normal pressure. The temperature was further increased, and the polymerization reaction was advanced by stirring at normal pressure. The polymerization temperature is preferably 280 ° C or lower, more preferably 270 ° C or lower, further preferably 265 ° C or lower, and most preferably 260 ° C or lower. Polymerization temperature When the temperature is higher than S280 ° C, the high molecular weight of the additive causes the side reaction of the polymer to proceed further, which is not preferable. The lower limit is preferably a temperature that does not solidify based on the polymer melting point. The polymerization time is preferably as short as possible, but is preferably within 2 hours, more preferably within 1.5 hours, and even more preferably within 1.0 hour.

[0067] When the target viscosity was reached, stirring was stopped and allowed to stand to remove bubbles in the polymer. It is not preferable to leave it for a long time because it causes heat deterioration. The molten resin was taken out from the outlet at the bottom of the reaction can, solidified by cooling, and a resin chip was obtained with a chip cutter such as a strand cutter. At this time, if the time required for casting is long, it is greatly affected by thermal oxidation deterioration at the take-out port, and the resin in the can is subjected to thermal deterioration, resulting in gelled products. Is generated or colored, which is not preferable. In addition, if the casting is too short, the temperature of the strand-shaped polymer coming out from the outlet becomes too high, which makes it easy to undergo thermal oxidative degradation of the resin additive, which may contribute to the deterioration of the thermal stability of the polymer. . Therefore

In the case of a batch reactor, the casting time is preferably 10 to 120 minutes, and more preferably 15 to LOO minutes. Moreover, the strand polymer temperature in that case becomes like this. Preferably it is 20-70 degreeC, More preferably, it is the range of 30-65 degreeC. As another method, a method of spraying an inert gas can be cited as a method for preventing the thermal acid deterioration of the polymer at the outlet.

 [0068] At this time, the phosphorus atom content (PC) and alkali metal atom content (M) derived from the phosphorus compound and alkali metal compound added during the production of the polyamide are within the ranges of the following formulas (2) and (3). It is preferable to satisfy the range. Since phosphorus compounds and alkali metals are hardly scattered outside the production process, the following formulas (2) and (3) are contained in the obtained polyamide together with the addition amount during the production of the polyamide. It is also a desirable range for the amount.

 [0069] 50≤PC <400ppm (2)

 [0070] 1 (MZPC) molar ratio 7 (3)

 [0071] With respect to the phosphorus atom content (PC), the lower limit is more preferably 60 ppm, and even more preferably 70 ppm or more. The upper limit is preferably 370 ppm, more preferably 350 ppm or less. The lower limit of the MZPC molar ratio is more preferably 1.3, and still more preferably 1.5 or more. If the phosphorus atom content (PC) is less than 50 ppm, the color tone of the polymer deteriorates. It is inferior to thermal stability and is not preferred. Conversely, if the phosphorus atom content (PC) force is OOppm or more, the raw material cost for the additive increases, which contributes to cost increases and the filter foreign matter clogging during melt molding increases. There is a concern that productivity will drop in the post-process. Further, if it is less than or equal to (MZPC) molar specific power, there is a risk of increasing the amount of gelled substances that increase in viscosity. On the other hand, if the (MZPC) ratio is 7 or more, the reaction rate is very slow, and the productivity decline cannot be denied.

 [0072] Examples of the phosphorus compound that suppresses the thermal deterioration of polyamide include compounds represented by the following chemical formulas (A-1) to (A-4).

Made of the polyamide of the present invention having good thermal stability and thermal acidity stability during drying and molding As the phosphorus compound used in the production, compounds represented by (A-1) and (A-3) are preferable. In particular, the compound represented by (A-1) is preferred.

 [0073] [Chemical 5]

[0074] [6]

0

 (A— 2) R4— P 1 0X4

[0075] [Chemical 7] ox ₂

(Λ− 3) _R 1 p− 0Χ ₃

[0076] [Chemical 8]

O 6

(A— 4) R _s O 1 P 1 OR '

(In the formulas (A-1), (A-2), (A-3) and (A-4), R to R are hydrogen, alkyl group, aryl group, cycloalkyl group or Reel alkyl group, X to X are hydrogen,

 15 Alkyl group, aryl group, cycloalkyl group, aryl group or alkali metal, alkaline earth metal, or one of X to X and R to R in each formula is connected to each other.

 1 5 1 7

 It can be linked to form a ring structure.

[0078] The phosphinic acid compound represented by the chemical formula (A-1) includes dimethylphosphinic acid, phenylmethylphosphinic acid, hypophosphorous acid, sodium hypophosphite, potassium hypophosphite, hypophosphorous acid. Lithium, magnesium hypophosphite, calcium hypophosphite, ethyl hypophosphite, [0079] [Chemical 9]

[0080] [Chemical 10]

[0081] and hydrolysates thereof, and condensates of the above phosphonic acid compounds.

 Of these, sodium hypophosphite, potassium hypophosphite, lithium hypophosphite, and magnesium hypophosphite are preferred! /.

[0082] Examples of the phosphonic acid compound represented by the chemical formula (A-2) include phosphonic acid, sodium phosphonate, potassium phosphonate, lithium phosphonate, potassium phosphonate, magnesium phosphonate, canoleum phosphonate, and phenol. Norephosphonic acid, ethinorephosphonic acid, sodium phenylrephosphonate, potassium phenylphosphonate, lithium phenylphosphonate, jetyl phenylphosphonate, sodium ethylphosphonate, potassium ethylphosphonate

[0083] The phosphonous acid compound represented by the chemical formula (A-3) includes phosphonous acid, sodium phosphonite, lithium phosphonite, potassium phosphonite, magnesium phosphonite, calcium phosphonite, -Phosphophosphonic acid, sodium phenylphosphonite, potassium phenylphosphonite, lithium phenolphosphonite, phenylphosphonite ethinore.

[0084] The phosphorous acid compound represented by the chemical formula (A-4) includes phosphorous acid, sodium hydrogen phosphite, sodium phosphite, lithium phosphite, potassium phosphite, Magnesium phosphate Examples include calcium phosphate, triethyl phosphite, triphenyl phosphite, and pyrophosphorous acid.

[0085] In the production of the polyamide of the present invention, an alkali metal-containing compound represented by the following chemical formula (B) is added.

[0086] Z— OR (B)

 8

 [Wherein Z is an alkali metal, R is hydrogen, an alkyl group, an aryl group, a cycloalkyl group,

 8

 — C (0) CH or — C (0) OZ, (Z is hydrogen, alkali metal))

 Three

 [0088] Examples of the alkaline compound represented by the chemical formula (B) include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, lithium acetate, sodium acetate, Examples include potassium acetate, rubidium acetate, cesium acetate, sodium methoxide, sodium ethoxide, sodium propoxide, sodium butoxide, potassium methoxide, lithium methoxide, sodium carbonate, etc. It is preferable to do this. However, any of them is not limited to these compounds.

 [0089] In order to add the phosphorus compound or the alkali metal-containing compound to the polyamide of the present invention, the raw material before the polymerization of the polyamide may be added during the polymerization, or may be melt-mixed into the polymer. These compounds may be added simultaneously or separately.

 [0090] The polyamide of the present invention has a relative viscosity of 1.5 to 4.0, preferably 1.5 to 3.0, more preferably 1.7 to 2.5, and even more preferably 1.8 to 2. The range is 0. If the relative viscosity is 1.5 or less, the molecular weight is too small, and the molded article such as a film made of the polyamide of the present invention may be inferior in mechanical properties. On the other hand, if the relative viscosity is 4.0 or more, it takes a long time for the polymerization, which may cause deterioration of the polymer and gelation, which may cause undesired coloration. Sometimes.

[0091] The shape of the polyamide chip of the present invention may be any of a cylinder, a square, a sphere, a flat plate, and the like. The average particle diameter is usually in the range of 1.0 to 5 mm, preferably 1.2 to 4.5 mm, more preferably 1.5 to 4. Omm. For example, in the case of a cylinder type, it is practical that the length is about 1.0 to 4 mm and the diameter is about 1.0 to 4 mm. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size and the minimum particle size is 0.7 times or more the average particle size. Also, the weight of the chip is in the range of 3-50mgZ It is practical.

 [0092] Further, it is desirable that the color b value (Co-b) of the polyamide chip of the present invention satisfies the following formula (1).

[0093]-5 <(Co-b) <10 (1)

 [0094] If the color b value (Co-b) is 10 or more, the hue of a molded article such as a bottle, a film, or a sheet becomes too yellow, and the commercial value decreases.

 [0095] The polyamide of the present invention can be molded into a desired final molded body by various molding techniques such as injection molding, extrusion molding, and blow molding. Examples of the molded body include sheets (single layer, multilayer), stretched film (single layer, multilayer), packaging materials such as hollow molded bodies, automobile parts, mechanical equipment parts, and laminates with paper.

 [0096] The polyamide of the present invention includes a lubricant, an antistatic agent, an antioxidant, an oxygen absorbent, an oxygen scavenger, an oxidation catalyst such as a cobalt compound, and an antiblocking agent within the range not impairing the object of the present invention. Stabilizers, dyes, pigments, glass fibers, carbon fibers, calcium carbonate, My strength, potassium titanate and other fibers or fillers can be added. In order to improve mechanical properties, particularly bending properties, flex resistance, etc., modified polyolefins, ionomer resins, elastomers and the like can also be added.

 [0097] Further, when the polyamide of the present invention is used as engineering plastics for molded products for heat resistance, weather resistance improving materials such as carbon black, copper oxide, alkali metal halide, hindered Thermal stabilizers such as phenol, thioether and phosphite, light stabilizers such as benzophenone, benzotriazole, cyanoacrylate and hindered phenol, higher fatty acid salts, higher fatty acids, higher fatty acid esters, low Release agents such as molecular weight polyolefin, fluidity improvers such as lower aliphatic carboxylic acids and aromatic carboxylic acids, antistatic agents, crystal nucleating agents, lubricants, pigments, dyes and the like may also be included.

 [0098] Further, when the polyamide of the present invention is used for a film, in order to improve handling properties such as slipping property, winding property and blocking resistance, it is preferable to use silicon oxide, calcium carbonate.

Inert such as inorganic particles such as magnesium carbonate, barium carbonate, calcium sulfate, barium sulfate, lithium phosphate, calcium phosphate, magnesium phosphate, calcium oxalate, etc. Particles can be included.

 [Aliphatic polyamide used in the present invention]

 Examples of the aliphatic polyamide used in the polyamide yarn composition of the present invention include polyamides obtained by ring-opening polymerization of ratatas such as ε-force prolactam, enantolactam, and lauryllatatum, ω-aminoheptanoic acid, Polyamides obtained by polycondensation of aminocarboxylic acids such as ω-aminoundecanoic acid, polyamides obtained by polycondensation of nylon salts of diamine and dicarboxylic acid, and various ratatas, aminocarboxylic acids and diamines described above. Examples thereof include a polyamide copolymer obtained by copolycondensation of a suitable mixture of a nylon salt with dicarboxylic acid. Specific examples of diamines include ethylenediamine, trimethylenediamine, hexamethylenediamine, metaxylylenediamine, paraxylylenediamine, cyclohexanediamine, 1,3-bisaminomethylcyclohexane, and the like. Examples thereof include aliphatic diamines and alicyclic diamines. Specific examples of the dicarboxylic acid include malonic acid, succinic acid, dartaric acid, adipic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid and other aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. And aromatic dicarboxylic acids.

 [0100] It is also preferable to use a polyamide-based block copolymer as a constituent of the polyamide composition of the present invention. It is also possible to use with the above aliphatic polyamide. Polyamide block copolymer is a polyamide block copolymer consisting of a hard segment composed of a polyamide component and a soft segment composed of a polyoxyalkylene glycol component. The polyamide component of the hard segment is ε Prolatatam, ω-amino fatty acid carboxylic acid, aliphatic diamine and aliphatic dicarboxylic acid, or group power consisting of aliphatic diamine and aromatic dicarboxylic acid is selected, specifically, latatam, aminoheptanoic acid such as ε-force prolatatam Examples thereof include aliphatic diamines such as: aliphatic dicarboxylic acids such as adipic acid, and aromatic dicarboxylic acids such as terephthalic acid. Examples of the polyoxyalkylene glycol constituting the soft segment of the polyamide-based block copolymer include polyoxytetramethylene glycol, polyoxyethylene glycol, polyoxy 1,2-propylene glycol, and the like.

[0101] The melting point of the polyamide block copolymer is a hard segment composed of a polyamide component. Force determined by the type and ratio of soft segment composed of a rubber component and a polyoxyalkylene glycol component. Usually, a range of 120 ° C to 180 ° C is used.

Specific examples include aliphatic polyamides such as nylon 4, nylon 6, nylon 7, nylon 11, nylon 12, nylon 66, nylon 46, and copolymers and mixtures thereof. Preferred aliphatic polyamides are nylon 6, nylon 66 and nylon 12.

 [0103] The aliphatic polyamide used in the present invention is produced by a known method. For example, it is produced by a method in which lactam is heated under pressure in the presence of a water solvent and polymerized while removing added water and condensed water. Further, it is produced by a method in which a diamine and a nylon salt having dicarboxylic acid strength are heated under pressure in the presence of an aqueous solvent and polymerized while removing added water and condensed water. Furthermore, it can also be produced by a method in which diamine is directly added to a molten dicarboxylic acid and polycondensed under normal pressure. In any case, a polymer which is further polymerized by solid phase polymerization after melt polymerization can be used.

 [0104] The relative viscosity of the aliphatic polyamide used in the present invention is preferably in the range of 1.7 to 5.5, and preferably 1.9 to 5.0. When the relative viscosity is less than 1.7, when the molded product such as a film having a low molecular weight of the aliphatic polyamide is used, the required mechanical strength is not exhibited, and since the melt viscosity is low, there is a problem in molding. Arise. When the relative viscosity exceeds 5.5, it is not preferable because the molding viscosity of the aliphatic polyamide is too high and the molding machine is overloaded and difficult to mix.

 [0105] Further, the ratio of the terminal amino group concentration and the terminal carboxyl group concentration of the aliphatic polyamide (terminal amino terminal group concentration Z terminal carboxyl group concentration) is preferably in the range of.

The range of 2 to 7 is more preferable. A range of 3 to 4 is more preferable. When trying to obtain a partially aromatic polyamide less than 0 or greater than 10, there is a problem in economic efficiency due to the time required for polycondensation.

[0106] The shape of the aliphatic polyamide or partially aromatic polyamide chip according to the present invention may be any of a cylinder type, a square type, a spherical shape, a flat plate shape, and the like. The average particle size is usually in the range of 1.0 to 5 mm, preferably 1.2 to 4.5 mm, more preferably 1.5 to 4. Omm. For example, in the case of a cylinder type, the length is 1.0 to 4 mm and the diameter is about 1.0 to 4 mm. Is practical. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size and the minimum particle size is 0.7 times or more the average particle size. The practical weight of the chip is 3-50mgZ.

 [0107] (Polyamide composition of the present invention)

 The polyamide composition of the present invention is a polyamide composition comprising the partially aromatic polyamide of the present invention and an aliphatic polyamide as main components.

 [0108] The polyamide composition of the present invention has the following two desired and embodiments of the polyamide composition (A) and the polyamide composition (B), depending on the intended properties and applications.

 [0109] [Polyamide composition (A)]

 The mixing ratio of the aliphatic polyamide and the partially aromatic polyamide constituting the polyamide composition of the present invention is 0.5 to 30 parts by weight, preferably 0 with respect to 100 parts by weight of the aliphatic polyamide. It is preferably 5 to 20 parts by weight. (Partial aromatic polyamide 0.5 to 30 parts by weight with respect to 100 parts by weight of aliphatic polyamide is converted to aliphatic polyamide Z partial aromatic polyamide = 99.5 / 0.5 to 76.9 / 23 1 (part by weight) o)

 By making the partially aromatic polyamide in the range of 0.5 to 30 parts by weight with respect to 100 parts by weight of the aliphatic polyamide, the polyamide composition is excellent in impact resistance and flex fatigue resistance, and consists of this polyamide composition. Sheets and stretched films are also excellent in impact resistance and flex fatigue resistance.

[0110] [Polyamide composition (B)]

 The mixing ratio of the partially aromatic polyamide and the aliphatic polyamide constituting the polyamide composition of the present invention is 0.5 to 100 parts by weight, preferably 1 to 100 parts by weight of the partially aromatic polyamide. It is preferably 0 to 70 parts by weight, more preferably 2.0 to 50 parts by weight. (0.5 to 100 parts by weight of aliphatic polyamide with respect to 100 parts by weight of partially aromatic polyamide is converted to partial aromatic polyamide Z aliphatic polyamide = 99.5 / 0.5 to 50Z50 (weight part ratio) )

Partially aromatic polyamide 100 parts by weight of aliphatic polyamide 0.5 to L00 parts by weight, the polyamide composition is excellent in oxygen gas barrier properties and heat resistance, and also satisfies bending fatigue resistance Sheet and stretched film made of this polyamide composition. It has excellent oxygen gas barrier properties and heat resistance, and has high strength.

 [0111] The following is common to the polyamide composition (A) and the polyamide composition (B).

 In the polyamide composition of the present invention, the aliphatic polyamide is nylon 6, and the structural unit derived from partially aromatic polyamidocaxylylenediamine and adipic acid is contained in the molecular chain by 50 mol% or more. A polyamide composition characterized by being a polyamide.

 [0112] Further, the polyamide composition of the present invention can contain a recovered product of the polyamide molded product from the polyamide composition, and the content thereof is relative to the mixture composed of the aliphatic polyamide and the partially aromatic polyamide. 30% by weight or less, preferably 25% by weight or less.

 If the content of the recovered product exceeds 30% by weight, the hue of the polyamide molded product becomes worse, which causes a problem, and deterioration of quality is observed due to the inclusion of gelled material.

 [0113] Here, the recovered product of the polyamide molded body constituting the polyamide composition of the present invention is a molded body or sheet-like product after the polyamide composition is heated and melted by a melt molding machine such as an injection molding machine or an extrusion molding machine. This is a polyamide molded product that is collected without being shipped as a product, mixed again with the polyamide composition of the purgen raw material, and used for molding, and is sometimes referred to as a “collected product”. Specifically, the collected products include products, intermediate products such as unstretched sheets, products that do not meet product standards, burrs such as runners that occur during molding, and ears that are generated when a stretched film is formed. These recovered products must be made about 1 to LOmm in size by methods such as cutting, crushing, melt extrusion, or compression molding, and a size almost comparable to the size of the virgin raw material is preferred. ,.

[0114] The water content of the polyamide composition of the present invention is preferably 250 to 1800 ppm, more preferably 300 to 1500 ppm. If the water content is less than 200 ppm, the melt viscosity at the time of melting will greatly increase, and the fluidity at the time of molding will decrease, resulting in poor transparency and surface smoothness of the resulting molded polyamide. It is a problem. On the other hand, if it exceeds 200 Oppm, the melt viscosity will decrease drastically, resulting in deterioration of the transparency and mechanical properties of the resulting polyamide molded product.

The moisture content of the polyamide composition is determined by measuring the moisture content of the sample taken periodically when drying the moisture-absorbed polyamide composition and ending the drying so that the moisture content is within the above range. After drying the hygroscopic polyamide composition to 200 ppm or less, It can be managed by a method of replenishing moisture to absorb moisture and adjusting the humidity to the above water content range.

 [0115] The polyamide composition of the present invention can be obtained by mixing an aliphatic polyamide and a partially aromatic polyamide, or a recovered product of the polyamide molded product, with a conventionally known method. For example, aliphatic polyamide chips and partially aromatic polyamide chips are dry-blended with a tumbler, V-type blender, Henschel mixer, etc., and the dry-blended mixture is a single-screw extruder, twin-screw extruder, kneader. Examples include those obtained by melting and mixing at least once, and those obtained by subjecting the molten mixture to solid phase polymerization under a high vacuum or an inert gas atmosphere as necessary.

 [0116] Further, the polyamide composition of the present invention may have a shape obtained by molding a melt mixture of an aliphatic polyamide and a partially aromatic polyamide. The molded state is not limited to a strand shape, a chip shape, or a cylinder shape, and may be a sheet shape, a film shape, or a pulverized product thereof. The shape is not particularly limited.

 [0117] The polyamide composition of the present invention includes a lubricant, an antistatic agent, an antioxidant, an oxygen absorbent, an oxygen scavenger, an antiblocking agent, a stabilizer, a dye, a pigment, silica, sulfuric acid, as necessary. Various additives such as inorganic fine particles such as lithium, magnesium oxide, alumina and zeolite, polymer organic lubricants such as acrylic and polystyrene, modified polyolefin, ionomer resin, thermoplastic resin such as elastomer, glass fiber Carbon fiber, calcium carbonate, my strength, fiber such as potassium titanate, or a kind of filler can be added.

 [0118] The polyamide composition of the present invention is a dry blended product, or a melt blended product that has been previously melt-blended by an extruder or the like and then pelletized, as a raw material, such as an injection molding method, an extrusion molding method, and a blow molding method. By molding technology, it can be molded into the desired final compact.

 [Polyamide molded product of the present invention]

 The polyamide molded body of the present invention is a polyamide molded body (A) or a polyamide molded body (B) described below depending on whether the polyamide composition used is a polyamide composition (A) or a polyamide composition (B). It is.

 [0120] [Polyamide molded product (A)]

Polyamide molded products include automotive parts, machine equipment parts, sheets, films (single layer, Layer), laminates with paper, blow bottles, etc., and secondary processed products include trays and vouchers. Further, the polyamide composition of the present invention can also be used as a component layer having various forms such as a film shape and a coating film shape in a composite molded body such as a laminated molded body and a laminated film.

 [0121] -Axially oriented polyamide film mainly composed of aliphatic polyamide is tough and excellent in impact resistance and bending fatigue resistance, and has excellent gas barrier properties, pinhole resistance, transparency, printability, etc. Therefore, it is widely used as a packaging material for various foods such as various liquid foods, water-containing foods, frozen foods, retort foods, pasty foods, and livestock and fishery products. The above-mentioned heat degradation of polyamide deteriorates transparency due to coloring due to heat deterioration, resulting in poor color appearance and poor appearance of the final bag product. In addition, the occurrence of foreign matter and fish eyes due to gelling due to thermal deterioration causes poor appearance such as ink loss during printing and contamination, and adhesion due to uneven application of adhesive during secondary processing of bag products. It becomes defective and bag-making property. Improvement of the thermal stability of the polyamide raw material greatly contributes to the solution of the above problems.

 [0122] [Polyamide molded product (B)]

 In addition, the polyamide composition of the present invention can be used as a component layer having various forms such as a film shape and a coating film shape in a composite molded body such as a laminated molded body and a laminated film. Polyamide molded products include automotive parts, machine equipment parts, sheets and biaxially stretched films (single layer and multilayer), laminates with paper, blow bottles, etc., and secondary cache products such as trays and pouches. Etc.

[0123] Partially aromatic polyamides, especially biaxially oriented polyamide films with Ny-MXD6 as the main component, have excellent oxygen gas barrier properties, transparency, printability, dimensional stability during heat treatment, etc. Therefore, it is widely used as a packaging material for various foods such as various water-containing foods, retort foods, pasty foods, livestock and fishery products. The thermal degradation of the partially aromatic polyamide described above results in poor transparency due to coloring due to thermal degradation, resulting in poor color appearance and poor appearance of the final bag product. In addition, the occurrence of foreign matter and fisheye caused by gelling due to thermal deterioration is poor appearance due to ink loss during printing, contamination with foreign matter, etc., and poor adhesion due to uneven application of adhesive during secondary processing on bag products. The bag-making property is poor. Improvement of the thermal stability of polyamide raw materials greatly contributes to the solution of the above problems. Example

 [0124] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The main characteristic value measuring methods in this specification will be described below.

 [0125] (1) Relative viscosity (RV) of polyamide

 0.25 g of a sample was dissolved in 25 ml of 96% sulfuric acid, 10 ml of this solution was measured at 20 ° C. with an Ostwald viscosity tube, and obtained from the following formula.

[0126] RV = t / t

 0

 (Where t is the number of seconds that the solvent falls) t is the number of seconds that the sample solution falls)

 0

[0127] (2) Structural analysis of phosphorus compounds in polyamide ( ³¹ P-NMR method)

Sample 340-350mg is dissolved in deuterated benzene Zl, 1, 1, 3, 3, 3-hexafluoroisopropanol = lZl (vol ratio) mixed solvent 2. 5ml at room temperature, and tri (t-butylphenyl) Add lOOppm of phosphoric acid (hereinafter abbreviated as TBPPA) to polyamide resin, add 0.1 ml of trifluoroacetic acid at room temperature, and after 30 minutes, Fourier transform nuclear magnetic resonance apparatus (manufactured by BRUK ER) AVANCE500) for ³¹ P-NMR analysis. The ³¹ P resonance frequency is 202.5 MHz, the detection pulse flip angle is 45 °, the data acquisition time is 1.5 seconds, the delay time is 1.0 second, the number of integrations is 1000 to 20000 times, the measurement temperature is room temperature, and the proton is completely decoupled. Analysis was performed under the conditions of

 [0128] From the obtained NMR chart, the peak integral value of each phosphorus compound is calculated, and from the following formula A, the phosphorus compound represented by the structural formula (formula 1) and the structural formula (formula 2) are represented. The molar ratio with the phosphorus compound was determined.

 [0129] Molar ratio of phosphorus compound = XP1ZXP2 (Formula A)

 (XP1 is the peak integral value of the phosphorus compound represented by the structural formula (formula 1), and XP2 is the peak integral value of the phosphorus compound represented by the structural formula (formula 2).)

[0131] Next, the P peak integral value corresponding to TBPPA (tri (t-butylphenyl) phosphate) was set to 10

Calculate the total P peak integral value PN, which is the total of each P peak integral value in the polyamide, observed in the region of 15 ppm to -15 ppm as Oppm.

[0132] Next, the P peak relative value (Ps) of all phosphorus compounds observed in the NMR ^ vector Calculate from Formula B.

[0133] P peak relative value (Ps) = PNZPC · · · · · (Formula B)

 (PN is the total P peak integral value (ppm) of polyamide, and PC is the phosphorus atom content (ppm) in the polyamide. Here, the phosphorus atom content PC in the polyamide is the following (4) (P peak relative ^ o Hh If the I value is greater than 1, P peak relative value = 1.)

 [0135] Next, the proportion of phosphorus compounds detected in the structure of structural formula (formula 1) in polyamide (Plr) and the proportion of phosphorus compounds detected in the structure of structural formula (formula 2) (P2r ) Is calculated from the following formulas C and D.

 [0136] Plr = Ps X (Peak integrated value of Linyi compound represented by structural formula (Formula 1) ΧΡ1) · ··· (Formula.)

 [0137] P2r = Ps X (Peak integrated value of phosphorus compound expressed by structural formula (Equation 2) ΧΡ2) · ··· (Equation D)

 [0138] When the peak relative value is smaller than 1, the total value of the ratio of each phosphorus compound in the polyamide does not become 100, but this does not dissolve in the preparation of the polyamide solution by the above method. This is because there are Linyi compounds.

 In the polyamides used in Examples and Comparative Examples, the phosphorous compound corresponding to the structural formula (Formula 1) is hypophosphorous acid (the following (Chemical Formula 11)), and the peak due to this structure is It was found in the range of 9-12 ppm. The phosphorus compound corresponding to the structural formula (Formula 2) was phosphorous acid (the following (Chemical Formula 12)), and the peak attributed to this structure was observed in the range of 4 to 7 ppm.

 [0140] [Chemical 11]

H-OH

[0141] [Chemical 12]

[0142] Next, the phosphorus atom content (P1) derived from the phosphorus compound detected in the structure of the structural formula (formula 1) and the phosphorus compound derived from the phosphorus compound detected in the structure of the structural formula (formula 2) according to the following formula: Obtain the phosphorus atom content (P2).

 [0143] Phosphorus compound-derived phosphorus atom content (PI) (ppm) detected in the structure of structural formula (Formula 1) = P C X Plr

 Phosphorus compound-derived phosphorus atom content detected in the structure of formula (Formula 2) (P2) (ppm) = P C X P2r

 [0144] (3) Color b value of polyamide chip and molded body (Co—b)

 The color b value was measured using a color meter (Nippon Denshoku, Model 1001DP).

 [0145] (4) Analysis of phosphorus atom content (PC) of polyamide

 The sample was subjected to dry ashing decomposition in the presence of sodium carbonate, or wet decomposition in sulfuric acid 'nitric acid' chloric acid system or sulfuric acid 'acidic acid-hydrogenated water system to convert phosphorus into normal phosphoric acid. Next, the molybdate is reacted in an lmolZL sulfuric acid solution to form phosphomolybdic acid, and this is reduced with hydrazine sulfate. The colorimetric determination was carried out by measuring in 02).

[0146] (5) Analysis of Na content (Na), Li content (Li), K content (Κ) of polyamide

 The sample was incinerated and decomposed with a platinum crucible, 6molZL hydrochloric acid was added and evaporated to dryness. 1. Dissolve in 2 molZL hydrochloric acid, and dissolve the solution by atomic absorption (AA-640-12, manufactured by Shimadzu Corporation).

[6] (6) Heat treatment of polyamide

 Samples vacuum-dried at 80 ° C for 16 hours under ltorr are placed in a 100 ml glass container (inner diameter 41 mm, trunk outer diameter 55 mm, overall height 95 mm), and a gear type aging tester NH manufactured by Nagano Science Machinery Co., Ltd. NH — Place on a 202GT turntable and heat for 5 hours at 120 ° C in an air atmosphere.

[0148] (7) Molding of stepped molded plate

Fig. 1 and Fig. 2 show polyamide chips that have been dried under reduced pressure to about 300ppm or less using a vacuum drier using an injection molding machine M-150C-DM type injection molding machine manufactured by Meiki Seisakusho. 2mm ~: L lmm (A part thickness = 2mm, B part thickness = 3mm, C part thickness = 4mm, D part thickness = 5mm, E part thickness = A stepped molded plate having a thickness of 10 mm and a thickness of F part = 1 lmm) was injection molded. In order to prevent moisture absorption of the chips during molding, the molding material hopper was purged with a dry inert gas (nitrogen gas).

 [0149] M-150C- DM injection molding machine has plasticity conditions as feed screw speed

 = 70%, screw speed = 120rpm, back pressure 0.5MPa, cylinder temperature was set to 260 ° C. The injection conditions were such that the injection speed and pressure holding speed were 20%, and the injection pressure and pressure holding were adjusted so that the molded body weight was 146 ± 0.2 g.

 The upper limit for injection time and pressure holding time is 10 seconds and 7 seconds, respectively, and the cooling time is set to 50 seconds. The total cycle time including the removal time of the molded body is about 75 seconds.

 [0150] Cooling water with a water temperature of 10 ° C is constantly introduced into the mold to control the temperature, but the mold surface temperature at the time of molding stability is around 22 ° C.

 The test plate for evaluating the compact strength was arbitrarily selected from 11 to 18 shots of the stable compact after the molding was started after the molding material was introduced and the resin was replaced. A 3 mm thick plate (Fig. 1, part B) was used for color measurement.

 [0151] (8) Moisture content of polyamide composition (Made by Mitsubishi Chemical Co., Ltd., Karl Fischer trace moisture analyzer CA-100 type and moisture vaporizer VA-100)

 Moisture vaporizer VA-100 manufactured by Mitsubishi Chemical Co., Ltd. was dried in advance in two drying cylinders (filled with silica gel and phosphorus pentoxide), and the furnace was heated to 180 ° C while flowing nitrogen gas at a flow rate of 250 mlZ. After heating, place the sample board in the heating furnace, and confirm that the dry nitrogen obtained from the heating furnace and the sample board is anhydrous with a trace moisture measuring device CA-100, then dry 3g of the sample. Weigh accurately in the dedicated sample container and place the sample on the sample board immediately. Sample force Vaporized moisture is transported by dry nitrogen to a trace moisture measuring device CA-100 model and subjected to Karl Fischer titration to determine the moisture content.

[0152] (9) Fabrication and Properties of Polyamide Stretched Film [When Polyamide Composition (A) is Used] A polyamide composition with a moisture content adjusted to a specific value and N, N'-ethylenebisstearamide ( After blending 0.15% by mass of Kyoeisha-gakusha light amide WE-183), it is melt extruded from the T die at a temperature of 260 ° C to a speed of 50mZmin. Then, it was electrostatically adhered to a metal roll cooled to 30 ° C. by DC high voltage imprinting and cooled and solidified to obtain a substantially unoriented sheet having a thickness of 200 m.

 A sheet obtained by cutting this sheet into a size of about 1 mm was used as a recovered product and used in Example 15 and Comparative Example 5.

 This sheet was first stretched in the machine direction at a stretching temperature of 85 ° C and 2.20 times, then held at 70 ° C, and subsequently stretched in the machine direction at a stretching temperature of 70 ° C and 1.50 times. In addition, this sheet was continuously guided to a tenter, stretched 4.0 times at 130 ° C, heat-fixed at 210 ° C, and subjected to 6.1% lateral relaxation treatment. After cooling, both edges were cut off and wound up to obtain a roll-shaped biaxially oriented polyamide-based resin film. The film temperature (stretching temperature) in the longitudinal stretching was measured using a radiation thermometer IR-004 manufactured by Minolta Co., Ltd. The stretching temperature in the transverse stretching was measured with a thermocouple installed in the tenter. Then, the hue, foreign matter, and film forming property of the obtained biaxially oriented polyamide resin film were evaluated.

[0153] (Hue of film)

 The hue of the end face of the stretched film roll was observed with the naked eye and evaluated as follows.

 A: Not much different from the hue of the chip before melting

 〇: Slightly yellower than the color of the chip before melting

 X: Colored yellow to brown from the color of the chip before melting

 X X: The color of the chips before melting is considerably brown

[0154] (Foreign matter on film)

Foreign matter was observed with the naked eye for 10 sheets of the stretched film lm ² and evaluated as follows.

 : No foreign matter

 ○: Almost no foreign matter

 X: Foreign matter present

[0155] (Film forming property)

 The film forming property in the first stretching step and the second stretching step was evaluated as follows.

 ○: Good film-forming properties in both the first stretching process and the second stretching process

Δ: Good film forming property in the first stretching process and poor film forming property in the second film forming process X: Film formation poor in both processes

[0156] (10) Film formation and properties of stretched polyamide film [When polyamide composition (B) is used] A polyamide composition having a moisture content adjusted to a specific value is removed from a T die by an extruder at 26 5 ° It is melt-extruded at a temperature of 30 mZmin at a temperature of C, and cooled and solidified on a metal roll that has been cooled to 30 ° C by electrostatic contact with a DC high-voltage load, and has a thickness of 200 μm. A substantially unoriented sheet was obtained.

 A sheet obtained by cutting the sheet into a size of about 1 mm was used as a recovered product and used in Example 24 and Comparative Example 12.

 The sheet was first stretched 2.00 times in the machine direction at a stretching temperature of 97 ° C, held at 75 ° C, and then second stretched in the machine direction at a stretching temperature of 75 ° C and 1.90 times. In addition, this sheet was continuously led to a tenter, stretched 4.0 times at 110 ° C, heat-fixed at 210 ° C, and subjected to 6.1% lateral relaxation treatment. After cooling, both edges were cut off and wound up to obtain a roll-shaped biaxially oriented polyamide-based resin film. The film temperature (stretching temperature) in the longitudinal stretching was measured using a radiation thermometer IR-004 manufactured by Minolta Co., Ltd. The stretching temperature in the transverse stretching was measured with a thermocouple installed in the tenter. Thereafter, the hue, foreign matter, and film forming property of the obtained biaxially oriented polyamide-based resin film were evaluated.

[0157] (Hue of film)

 The hue of the end face of the stretched film roll was observed with the naked eye and evaluated as follows.

 A: Not much different from the hue of the chip before melting

 〇: Slightly yellower than the color of the chip before melting, but no problem for practical use X: Colored yellow to brown from the color of the chip before melting

 X X: The color of the chips before melting is considerably brown

[0158] (Foreign matter on film)

Foreign matter was observed with the naked eye for 10 sheets of the stretched film lm ² and evaluated as follows.

 : No foreign matter

 ○: Almost no foreign matter

X: Foreign matter present [0159] (Film forming property)

 The film forming property in the first stretching step and the second stretching step was evaluated as follows.

 ○: Good film-forming properties in both the first stretching process and the second stretching process

 Δ: Good film forming property in the first stretching process and poor film forming property in the second film forming process X: Poor film forming property in both processes

[Polycabramid (Ny6) used in Examples and Comparative Examples]

 Using a 100-liter batch polymerization kettle, nylon 6 obtained by ring-opening polymerization of ε-strength prolatatum was used as a polyamide-based resin. The nylon 6 chip is extracted with hot water using a batch polymerization kettle to reduce the monomer and oligomer content to 1% by weight, and then dried to a moisture content of 0.1% by weight. used. The relative viscosity of raw material nylon 6 and stretched film was about 2.8 measured at 20 ° C using 96% concentrated sulfuric acid solution. The surface protrusion-forming fine particles (0.45% by weight) used were silica fine particles with a pore volume of 1.6 cc / g and an average particle size of 1.8 / zm (Fuji Silysia Chemical Co., Ltd., Silicia 350). It was dispersed in an aqueous solution of ε-force prolatatum, which is a raw material of Nylon 6, with a high-speed stirrer, charged into a polymerization kettle, and dispersed in nylon 6 in the polymerization process.

[0161] (Metaxylylene group-containing polyamide used in Examples and Comparative Examples)

 The polyamide used was a material such as metaxylylenediamine or adipic acid in a pressure-resistant polycondensation kettle, or sodium hydroxide (NaOH) or sodium hypophosphite (NaH PO · Η Ο).

 2 2 2 Obtained by a batch method in which polycondensation is carried out by heating under pressure and normal pressure in the presence of an additive.

 [0162] (Ny-MXD6 (A))

 Precisely weigh metaxylylenediamine, adipic acid and water in an adjustment can equipped with a stirrer, a condenser, a thermometer, a dropping funnel and a nitrogen gas inlet tube, pressurize and release with nitrogen gas The above operation was repeated 5 times to perform nitrogen substitution, and the oxygen content in the atmospheric nitrogen was adjusted to 9 ppm or less. The internal temperature at that time was 80 ° C. Sarakuko, NaOH and NaH PO as additives

 twenty two

• H 2 O was added and stirred to obtain a uniform salt solution. Also in this case, oxygen content in the atmosphere nitrogen

2

 The amount was kept below 9 ppm.

[0163] This solution was mixed with a stirrer, a partial reducer, a thermometer, a dropping funnel and a nitrogen gas introduction pipe. The can was transferred to a can, the temperature inside the can was 190 ° C, and the pressure inside the can was 1. OMPa. The reaction time until this time was 4.5 hours. After that, the internal pressure of the can was gradually released over 60 minutes and returned to normal pressure. The temperature was further raised to 255 ° C, and the mixture was stirred at normal pressure for 20 minutes to reach a predetermined viscosity, and the reaction was completed. Then, it was allowed to stand for 20 minutes to remove bubbles in the polymer, extruded molten resin from the bottom of the reaction can, and cast while cooling and solidifying with cold water. The casting time was about 70 minutes, and the temperature of the cooled and solidified resin was 50 ° C. The total amount of sodium atoms of sodium hypophosphite and sodium hydroxide was 2.7 moles of phosphorus atoms. Table 1 shows the characteristics.

 [0164] (Ny-MXD6 (B))

 It was obtained by the same polymerization method as Ny—MXD6 (A) except that the polymerization time was extended. Table 1 shows the characteristics.

 [0165] (Ny-MXD6 (C))

 It was obtained by the same polymerization method as Ny—MXD6 (A) except that the amount of additive used was changed.

 The total amount of sodium atoms of sodium hypophosphite and sodium hydroxide was 3.4 times mol of phosphorus atoms. Table 1 shows the characteristics.

[0166] (Ny-MXD6 / MXDI (D))

 It was obtained by the same polymerization method as Ny-MXD6 (A) except that metaxylylenediamine, adipic acid and isophthalic acid were adjusted as raw materials so as to correspond to the compositions shown in Table 1.

 The total amount of sodium atoms of sodium hypophosphite and sodium hydroxide was 2.7 moles of phosphorus atoms. Table 1 shows the characteristics.

[0167] (Ny-MXD6 / MXD-CHDA (E))

 Obtained by the same polymerization method as Ny-MXD6 (A), except that metaxylylenediamine, adipic acid and cyclohexanedicarboxylic acid (C HDA) were adjusted as raw materials to correspond to the composition described in Table 1. It is a thing.

The amount of sodium is the sodium atom of sodium hypophosphite and sodium hydroxide. The total amount of was 2.7 moles of phosphorus atoms. Table 1 shows the characteristics.

[0168] (Ny- MXD6 (F))

 Ny—Use the same reactor as in MXD6 (A), change the amount of additive used, and do not replace nitrogen gas in the raw material salt adjustment can, so that the oxygen concentration in the atmosphere remains at about lOOppm. The water inside the can was 190 ° C, and the pressure inside the can was 1. OMPa. The internal temperature and reaction time up to this point were almost the same as Ny—MXD6 (A). After that, the internal pressure of the can was gradually released over 60 minutes and returned to normal pressure. The temperature was further raised to 283 ° C, and the mixture was stirred at normal pressure for 20 minutes to reach a predetermined viscosity, and the reaction was completed. Thereafter, casting was performed in the same manner as Ny—MXD6 (A).

 The total amount of sodium atoms in sodium hypophosphite and sodium hydroxide was 2.7 moles of phosphorus atoms. Table 1 shows the characteristics.

[0169] (Ny- MXD6 (G))

 The phosphorous atom-containing compound and the alkali compound were not added and were obtained by the same polymerization method as for Ny-MXD6 (A). Table 1 shows the characteristics.

[0170] (Ny- MXD6 (H))

 The additive was obtained by the same polymerization method as Ny-MX D6 (A) except that lithium hydroxide or lithium hypophosphite was used as an additive.

 The total amount of lithium atoms in lithium hypophosphite and lithium hydroxide was 2.7 times mol of phosphorus atoms. Table 2 shows the characteristics.

[0171] (Ny- MXD6 (I))

 It was obtained by the same polymerization method as Ny-MXD6 (A) except that it was changed to sodium hydroxide or magnesium hypophosphite as an additive.

 The amount of sodium was 2.7 moles of phosphorus atoms as sodium atoms of sodium hydroxide. Table 2 shows the characteristics.

[0172] (Ny- MXD6 (J))

 The additive was obtained by the same polymerization method as Ny-MX D6 (A) except that it was changed to potassium hydroxide or potassium hypophosphite.

The amount of potassium is the sum of potassium atoms of potassium hypophosphite and potassium hydroxide. The amount was set to 2.7 moles of phosphorus atoms. Table 2 shows the characteristics.

[0173] [Table 1]

 [0174] [Table 2]

 [0175] (Example 1)

 Evaluation was carried out by the methods (6) and (7) using Ny-MXD6 (A). The results are shown in Table 3.

 Both the hue after heat treatment and the hue of the molded product were problematic.

[0176] (Example 2)

 Evaluation was carried out by the methods (6) and (7) using Ny-MXD6 (B). The results are shown in Table 3.

 Both the hue after heat treatment and the hue of the molded product were problematic.

[0177] (Example 3)

 Evaluation was performed by the methods (6) and (7) using Ny-MXD6 (C). The results are shown in Table 3.

 Both the hue after heat treatment and the hue of the molded product were problematic.

[0178] (Examples 4 to 8) Evaluation was carried out by the methods (6) and (7) using various polyamides described in Table 1 and Table 2.

 The results are shown in Table 3.

 Both the hue after heat treatment and the hue of the molded product were problematic.

[0179] (Comparative Example 1 2)

 Evaluation was performed by the methods (6) and (7) using Ny-MXD6 (D) and (E). The results are shown in Table 3.

 Both the hue after heat treatment and the hue of the molded product were bad.

[0180] [Table 3]

 [0181] (Example 9)

 Using the polyamide composition described in Table 4, the evaluation was performed by the method (9). The results are shown in Table 4.

 The film-forming property, hue, and foreign matter all had problems.

[0182] (Example 10 15)

 In the same manner as in Example 9, the polyamide compositions shown in Table 4 were evaluated.

 The results are shown in Table 4.

 The film-forming property, hue, and foreign matter all had problems.

[0183] (Comparative Example 3 4) In the same manner as in Example 9, the polyamide compositions shown in Table 4 were evaluated.

 The results are shown in Table 4.

 Film formation was a problem, but hue and foreign matter were problems.

[0184] (Comparative Examples 5 and 6)

 In the same manner as in Example 9, the polyamide compositions shown in Table 4 were evaluated. The results are shown in Table 4.

 Although there was no problem in film forming property, both hue and foreign matter were problems.

[0185] (Comparative Example 7)

 The polyamide compositions shown in Table 4 were evaluated in the same manner as in Example 11 except that the water content was changed.

 The results are shown in Table 4.

 There was no problem with the hue, but there was a foreign matter with poor film-forming properties, which was a problem.

[0186] (Comparative Example 8)

 The polyamide compositions shown in Table 4 were evaluated in the same manner as in Example 11 except that the water content was changed.

 The results are shown in Table 4.

 The hue and foreign matter were problematic, but the film-forming property was bad.

[0187] (Comparative Example 9)

 The polyamide compositions shown in Table 4 were evaluated in the same manner as in Example 11 except that the water content was changed.

 The results are shown in Table 4.

 The hue and foreign matter were problematic, but the film-forming property was bad.

[0188] [Table 4] 謹 i ”leakage i” leakage i ”leakage i” leakage i ”leakage i” leakage i ”leakage i”

 Four

 Polya 99 95 95 95 90 90 90 90 90 80 95 95 95

 Composition 1 5

 Weight

 咅

10 10 20 5 5 5 Production department 10 10

 Moisture content 3D 250 誦 1330 a) Leakage 3D 5∞ 60 3X0 25∞ Total O O O O o O o o O o Δ Ilm

 Hue O © © O © O o © © ©> ® ® ® ® o o o ® ®

[0189] (Example 16)

 Using the polyamide composition described in Table 5, the evaluation was carried out by the method (10). The results are shown in Table 5.

 The film-forming property, hue, and foreign matter all had problems.

[0190] (Examples 17 to 29)

 In the same manner as in Example 16, the polyamide compositions shown in Table 5 were evaluated.

 The results are shown in Table 5.

 The film-forming property, hue, and foreign matter all had problems.

[0191] (Comparative Examples 10 to 13)

 In the same manner as in Example 16, the polyamide compositions shown in Table 6 were evaluated.

 The results are shown in Table 6.

 Film formation was a problem, but hue and foreign matter were problems.

[0192] (Comparative Example 14)

 The polyamide compositions shown in Table 6 were evaluated in the same manner as in Comparative Example 11 except that the water content was changed.

 The results are shown in Table 6.

 There was no problem with the hue, but there was a foreign matter with poor film-forming properties, which was a problem.

[0193] (Comparative Example 15)

The polyamide compositions shown in Table 6 were evaluated in the same manner as in Comparative Example 11 except that the water content was changed. The results are shown in Table 6.

 The hue and foreign matter were problematic, but the film-forming property was bad.

[0194] (Comparative Example 16)

 Evaluations were carried out on the polyamide compositions shown in Table 6 in the same manner as in Comparative Example 11 except that the water content was changed.

 The results are shown in Table 6.

 The hue and foreign matter were problematic, but the film-forming property was bad.

[0195] [Table 5]

[0196] [Table 6]

 [0197] While the polyamide and the polyamide composition of the present invention have been described based on a plurality of examples, the present invention is not limited to the configurations described in the above examples, and the configurations described in the examples. The configuration can be changed as appropriate without departing from the spirit of the invention, for example, by appropriately combining them.

 Industrial applicability

[0198] Since the polyamide of the present invention has good thermal stability and thermal acidity stability at the time of drying and molding, it has excellent color tone and is difficult to be colored in the molding process. Is used as a material for molded products such as films and sheets, hollow molded containers such as beverage bottles, and engineering plastics. Can be manufactured. Furthermore, the polyamide composition of the present invention is also excellent in color tone and is difficult to be colored in the molding process because it has good thermal stability and thermal acidity stability during drying and molding. Since there is little generation of foreign matters such as a shaped product, it is suitably used as a material such as a molded product such as a film or a sheet, a hollow molded product or an engineering plastics material, and these molded products can be produced with high productivity.

Claims

Claims [1] Polyamide having a unit derived from an aliphatic dicarboxylic acid and an aromatic diamine as a main constituent unit, or a unit derived from an aromatic dicarboxylic acid and an aliphatic diamine as a main constituent unit If the polyamide is dissolved in a 31 P-NMR measurement solvent and trifluoroacetic acid is added and then structural analysis is performed, the phosphorus atom content derived from the phosphorus compound detected by the structure of the following structural formula (formula 1) A polyamide characterized in that (P1) is 10 ppm or more.

 [Chemical 1]

(Formula 1)

(However, R and R are hydrogen, alkyl group, aryl group, cycloalkyl group or aryl group.

 1 2

 Rualkyl group, X is hydrogen)

[2] When the polyamide is dissolved in a ³¹ P-NMR measurement solvent and subjected to structural analysis after addition of trifluoroacetic acid, the phosphorus atom content derived from the phosphorus compound detected by the structure of the following structural formula (formula 2) (P 2. The polyamide according to claim 1, wherein 2) is 30 ppm or more.

 [Chemical 2]

(Formula 2)

(Where R is hydrogen, alkyl, aryl, cycloalkyl or arylalkyl.

 Three

 R group, X and X are hydrogen)

 twenty three

 [3] Polyamide strength The polyamide according to claim 1, wherein the molecular chain contains 50 mol% or more of structural units derived from metaxylylenediamine and dicarboxylic acid.

[4] The polymer according to claim 1 or 2, wherein the polyamide contains at least 50 mol% of a structural unit derived from metaxylylenediamine and adipic acid in the molecular chain. Riamide.

 [5] The polyamide b according to any one of claims 1 to 4, wherein the color b value (Co-b) force of the polyamide chip satisfies the following formula (1).

 -5 <(Co -b) <10 (1)

[6] A polyamide composition comprising the polyamide according to any one of claims 1 to 5 and an aliphatic polyamide as main components.

 [7] A polyamide composition mainly comprising 100 parts by weight of an aliphatic polyamide and 0.5 to 30 parts by weight of the polyamide according to any one of claims 1 to 5.

[8] A polyamide composition mainly comprising 100 parts by weight of the polyamide according to any one of claims 1 to 5 and 0.5 to 100 parts by weight of an aliphatic polyamide.

[9] The polyamide composition according to any one of [6] to [8], wherein the aliphatic polyamide is nylon 6.

 [10] The polyamide composition according to any one of claims 6 to 9, further comprising a recovered product of the polyamide molded product from the polyamide composition.

[11] The polyamide composition according to any one of [6] to [10], wherein the water content is 200 to 2000 ppm.

[12] A polyamide molded article obtained by molding the polyamide composition according to any one of claims 6 to 11.

 [13] A polyamide molded article comprising at least one layer formed by melt-molding the polyamide composition according to any one of claims 6 to 11.

[14] A polyamide molded body characterized in that it is a polyamide molded body sheet according to claim 12 or 13, or a stretched film obtained by stretching the sheet in at least one direction.