JP2012136643A - Copolyamide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copolyamide having a high melting point of not lower than 280°C and low susceptibility to water, and further highly satisfying all of the three characteristics of moldability, thermal aging resistance and a gasoline barrier property.SOLUTION: The copolyamide includes: (a) 50 to 97 mol% of a constituent unit obtained from an equimolar salt of aliphatic diamine having 4 to 12 methylene chains and terephthalic acid; and (b) 50 to 3 mol% of a constituent unit obtained from 11-amino undecanoic acid or undecane lactam. The melting point (Tm) of the copolyamide is preferably 280 to 320°C and the heating crystallization temperature (Tc1) thereof is preferably 90 to 140°C.

Description

  The present invention relates to a novel polyamide highly satisfying all three properties of moldability, heat aging resistance, and gasoline barrier property in addition to high melting point and low water absorption.

  In recent years, high performance has been demanded for polyamides used in the fields of electric / electronic parts, automobile parts, engineering plastics, etc. For example, in the case of electric / electronic parts, reflow is performed with the development of surface mounting technology (SMT). High heat resistance such as solder heat resistance is required. In addition, in automobile parts such as engine room parts, there is a demand for polyamides having higher heat resistance than before. Furthermore, coupled with the expansion of the use of polyamide, polyamides having further improved physical properties and functions are required not only for electric / electronic parts and automobile parts, but also in other application fields. In addition, there is a demand for the development of polyamides that are excellent in dimensional stability, mechanical properties, chemical resistance, and the like.

  As polyamides used for molding materials, sliding materials and the like, 6T nylon synthesized by a co-condensation polymerization reaction of hexamethylenediamine (6) and terephthalic acid (T) is well known. 6T nylon is a polyamide with a good balance of resin properties such as heat resistance, mechanical properties, chemical resistance, sliding properties, gas barrier properties, and gasoline barrier properties, but 6T nylon that is not copolymerized has a melting point of 360. Since it exceeds 0 ° C., it has a drawback that it is difficult to polymerize the polymer and to shape the obtained polymer. Therefore, 6T nylon is copolymerized with a dicarboxylic acid component such as adipic acid or isophthalic acid, or an aliphatic polyamide such as nylon 6 in an amount of 30 to 50 mol%, so that the temperature can be practically used, that is, about 280 to 320 ° C. The current situation is that the melting point is lowered. Copolymerizing such a large amount of the third component, and optionally further the fourth component, is certainly effective for lowering the melting point of the polymer, but on the other hand, the crystallinity decreases, the ultimate crystallinity decreases, This is accompanied by a decrease in heat resistance and a decrease in thermal stability.As a result, various performances such as rigidity, chemical resistance, dimensional stability, and melt stability at high temperatures are reduced. In some cases, this leads to a decrease in productivity.

  For example, Patent Document 1 discloses a binary copolymer polyamide obtained by copolymerizing a relatively large amount of 11 nylon or 12 nylon with 6T nylon. This copolymerized polyamide has the advantages of low water absorption and excellent mechanical properties, but has the disadvantage of being inferior in moldability, heat aging resistance and gasoline barrier properties.

  Patent Document 2 discloses 9T nylon synthesized by co-condensation polymerization of 1,9-nonamethylenediamine (9) and terephthalic acid (T). 9T nylon has the advantages of low water absorption and excellent mechanical properties, but has the disadvantage of significantly poor moldability.

  Further, Patent Document 3 discloses 9T / M8T nylon copolymerized with 2-methyl-1,8-octanediamine (M8) in part of nonamethylenediamine. 9T / M8T nylon is able to improve moldability because it contains structural units derived from 2-methyl-1,8-pentanediamine (M8) and terephthalic acid (T). It is not possible to fully satisfy both barrier properties.

  Thus, nylons obtained from conventionally known aliphatic diamines and terephthalic acid have all three characteristics of moldability, heat aging resistance, and gasoline barrier properties while maintaining a high melting point and low water absorption. There was nothing to be satisfied with.

JP-A-5-310925 Japanese Patent Laid-Open No. 07-228690 Japanese Patent Laid-Open No. 07-228689

  The present invention was invented in view of the current state of the prior art, and its purpose is to have three characteristics of a high melting point of 280 ° C. or higher, low water absorption, moldability, heat aging resistance, and gasoline barrier properties. It is an object of the present invention to provide a novel polyamide that satisfies all of the above requirements.

  In order to achieve the above object, the inventor of the present invention has the following types of components to be copolymerized with nylon as a structural unit obtained from an equimolar molar salt of an aliphatic diamine having 4 to 12 methylene chains and terephthalic acid: As a result of intensive studies on the amount, by copolymerizing 11 nylon at a specific ratio, in addition to high melting point and low water absorption, all three properties of moldability, heat aging resistance, and gasoline barrier property are highly advanced. The present inventors have found that a satisfactory new copolymer nylon can be provided and have completed the present invention.

  That is, according to the present invention, (a) 50 to 97 mol% of a structural unit obtained from an equimolar salt of an aliphatic diamine having 4 to 12 methylene chains and terephthalic acid, and (b) 11-aminoundecane There is provided a copolymerized polyamide comprising 50 to 3 mol% of a structural unit obtained from an acid or undecane lactam.

  According to a preferred embodiment of the copolymerized polyamide of the present invention, the aliphatic diamine as component (a) is 1,4-tetramethylenediamine, 1,5-pentamethylenediamine, 1,9-nonamethylenediamine, 1,11. Selected from the group consisting of undecamethylenediamine, 1,12-dodecamethylenediamine and mixtures thereof, and the melting point (Tm) of the copolyamide is 280 to 320 ° C., and the temperature rising crystallization temperature (Tc1) is 90 ~ 140 ° C.

  The copolymer polyamide of the present invention is obtained with component (a) such as mechanical properties and slidability because 11 nylon is copolymerized at a specific ratio in the structural unit obtained from component (a). In addition to the high melting point of 280 ° C. and low water absorption, the moldability, heat aging resistance, and gasoline barrier properties can be highly satisfied.

  Hereinafter, the copolymerized polyamide of the present invention will be described in detail. The copolymerized polyamide of the present invention contains the component (a) as a main component and the component (b) corresponding to 11 nylon in a specific ratio, and is a drawback of the structural unit obtained from the component (a). Not only is some formability improved, but also heat aging resistance and gasoline barrier properties are highly satisfactory.

The component (a) is a polyamide of a structural unit obtained from an equivalent molar salt of an aliphatic diamine having 4 to 12 methylene chains and terephthalic acid, and is specifically represented by the following formula (I) Is. N in the formula represents the number of methylene chains and is in the range of 4-12.

  The component (a) is a main component of the copolymerized polyamide of the present invention, and has a role of imparting excellent heat resistance, mechanical properties, chemical resistance, slidability, gas barrier properties and the like to the copolymerized polyamide. The blending ratio of the component (a) in the copolymerized polyamide is 50 to 97 mol%, preferably 65 to 95 mol%, more preferably 70 to 95 mol%. When the blending ratio of the component (a) is less than the above lower limit, the component (a), which is a crystal component, is subject to crystal inhibition by the copolymer component and may cause deterioration of moldability and high temperature characteristics, while exceeding the above upper limit. In such a case, the melting point becomes too high, and there is a possibility of decomposition during processing, which is not preferable.

  Specific aliphatic diamines used for component (a) include 1,4-tetramethylene diamine, 5-pentamethylene diamine, 1,6-hexamethylene diamine, 1,7-heptamethylene diamine, and 1,8-octa. Methylene diamine, 1,9-nonamethylene diamine, 1,10-decamethylene diamine, 1,11-undecamethylene diamine, 1,12-dodecamethylene diamine, and the like are mentioned. Among them, from the viewpoint of water resistance, 1, 9-nonamethylenediamine, 1,11-undecamethylenediamine, and 1,12-dodecamethylenediamine are preferred. Further, as the aliphatic diamine used for the component (a), a branched diamine having 4 to 12 carbon atoms may be used in combination. Specific branched diamines include 1,2-diaminopropane, 1,3-diaminopentane, 2-ethyl-1,4-diaminobutane, 2-methyl-1,5-diaminopentane, and 2,4-dimethyl. -1,7-heptanediamine, 2-methyl-1,8-diaminooctane, 2,2,4-trimethyl-1,6-diaminohexane, 2,4,4-trimethyl-1,6-diaminohexane It is done. Among them, a diamine in which the difference in carbon number between the straight chain portion of the straight chain diamine and the branched diamine is in the range of 2 to 4 is preferable.

The component (b) corresponds to 11 nylon obtained by polycondensation of 11-aminoundecanoic acid or undecane lactam, and is specifically represented by the following formula (II).

  The component (b) is for improving the drawbacks of the component (a), and lowers the melting point and temperature rising crystallization temperature of the copolymerized polyamide to improve the moldability and reduce the water absorption rate. It has the role of improving troubles caused by changes in physical properties and dimensions during water absorption. The blending ratio of the component (b) in the copolymerized polyamide is 50 to 3 mol%, preferably 35 to 5 mol%, more preferably 30 to 5 mol%. When the blending ratio of the component (b) is less than the above lower limit, the melting point of the copolyamide is not sufficiently lowered, the moldability may be insufficient, and the effect of reducing the water absorption rate of the obtained resin is insufficient. In addition, there is a risk of instability of physical properties such as deterioration of characteristics at the time of water absorption. When the above upper limit is exceeded, the melting point of the copolyamide is too low, the crystallization rate is slow, the moldability may be adversely affected, and the amount of the component (a) is reduced, and the mechanical properties and sliding properties are reduced. There is a possibility that the mobility is insufficient, which is not preferable.

  In addition to the components (a) and (b), the copolymerized polyamide of the present invention includes (c) a structural unit obtained from an equimolar molar salt of a diamine other than the structural unit (a) and a dicarboxylic acid, or an amino A structural unit obtained from carboxylic acid or lactam may be copolymerized at a maximum of 20 mol%. The component (c) imparts other characteristics that cannot be obtained by the copolymerized polyamides of the component (a) and the component (b), and specific examples thereof include the following copolymer components. As the amine component, 1,2-ethylenediamine, 1,3-trimethylenediamine, 1,13-tridecamethylenediamine, 1,16-hexadecamethylenediamine, 1,18-octadecamethylenediamine, 2,2, Aliphatic diamines such as 4 (or 2,4,4) -trimethylhexamethylenediamine, piperazine, cyclohexanediamine, bis (3-methyl-4-aminohexyl) methane, bis- (4,4'-aminocyclohexyl) Examples thereof include alicyclic diamines such as methane and isophoronediamine, aromatic diamines such as metaxylylenediamine, paraxylylenediamine, paraphenylenediamine and metaphenylenediamine, and hydrogenated products thereof. As the acid component of the polyamide, the following polyvalent carboxylic acids or acid anhydrides can be used. Examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, and 2,2′-diphenyl. Aromatic dicarboxylic acids such as dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 5-sulfonic acid sodium isophthalic acid, 5-hydroxyisophthalic acid, fumaric acid, maleic acid, succinic acid, itaconic acid, adipic acid, azelaic acid, Sebacic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid, 1,18-octadecanedioic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohex Njikarubon acid, and an aliphatic or alicyclic dicarboxylic acids such as dimer acid. Further, lactams such as ε-caprolactam and 12-lauryl lactam, and aminocarboxylic acids having a structure in which they are ring-opened can be used.

  Specific examples of the component (c) include polycaproamide (nylon 6), polydodecanamide (nylon 12), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyun Decamethylene adipamide (nylon 116), polymetaxylylene adipamide (nylon MXD6), polyparaxylylene adipamide (nylon PXD6), polytetramethylene sebamide (nylon 410), polyhexamethylene sebacamide (Nylon 610), polydecamethylene adipamide (nylon 106), polydecamethylene sebamide (nylon 1010), polyhexamethylene dodecamide (nylon 612), polydecamethylene dodecamide (nylon 1012), polyhexamethylene Isophthalamide (Niro 6I), polybis (3-methyl-4-aminohexyl) methane terephthalamide (nylon PACMT), polybis (3-methyl-4-aminohexyl) methane isophthalamide (nylon PACMI), polybis (3-methyl-4-amino) Hexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-aminohexyl) methane tetradecamide (nylon PACM14), and the like.

  Among the structural units, examples of the preferred component (c) include polyhexamethylene adipamide for imparting high crystallinity to the copolymer polyamide, and polydecamethylene dodecamide for imparting further low water absorption. And polymetaxylene adipamide for improving gasoline barrier properties. The blending ratio of the component (c) in the copolymerized polyamide is preferably up to 20 mol%, more preferably 10 to 20 mol%. When the proportion of the component (c) is less than the above lower limit, the effect of the component (c) may not be sufficiently exhibited. When the proportion exceeds the above upper limit, the amount of the essential component (a) or component (b) is small. Therefore, the originally intended effect of the copolymerized polyamide of the present invention may not be sufficiently exhibited, which is not preferable.

  The copolymer polyamide of the present invention preferably has a melting point (Tm) of the copolymer polyamide of 280 to 320 ° C and a temperature rising crystallization temperature (Tc1) of 90 to 140 ° C. When Tm exceeds the above upper limit, the processing temperature required when the copolymerized polyamide is molded by an injection molding method or the like becomes extremely high, so that it may be decomposed during processing and the desired physical properties and appearance may not be obtained. On the other hand, when Tm is less than the lower limit, the crystallization rate becomes slow, and molding becomes difficult. Further, when Tc1 exceeds the above upper limit, not only the mold temperature required for molding the copolymer polyamide by an injection molding method becomes high and molding becomes difficult, but in a short cycle of injection molding, In some cases, crystallization does not proceed sufficiently, causing molding difficulties such as insufficient mold release, and in subsequent use, crystallization proceeds at high temperatures and deformation due to secondary shrinkage becomes a problem. Conversely, when Tc1 is less than the above lower limit, it is necessary to inevitably lower the glass transition temperature as a resin composition. Since Tc1 is generally a temperature higher than the glass transition temperature, when Tc1 is less than 90 ° C., a low value is required as the glass transition temperature. In that case, there is a large decrease in physical properties or physical properties after water absorption. Problems such as inability to maintain. Since Tg needs to be kept relatively high, Tc1 needs to be at least 90 ° C. or higher.

  In the copolymerized polyamide of the present invention, a specific amount of 11 nylon component is copolymerized with a polyamide of a structural unit obtained from an equimolar molar salt of an aliphatic diamine having 4 to 12 methylene chains and terephthalic acid. In addition to properties such as melting point and low water absorption, a resin having an excellent balance of moldability, heat aging resistance, and gasoline barrier properties can be obtained. In the molding of electronic parts, in addition to a high melting point of 280 ° C. or higher and low water absorption, thin-walled, high-cycle molding is required. In the hexamethylene terephthalamide / polyhexamethylene adipamide copolymer (PA6T / 66), although the moldability is good, the water absorption is extremely high. Therefore, in the reflow soldering process performed by surface mounting or the like, there is a problem that blisters are generated in a molded product. On the other hand, polynonamethylene terephthalamide has low water absorption, but Tc1 may be 150 ° C. or higher, and the mold temperature at the time of molding is required to be 150 ° C. or higher. . Even if it can be molded with a low temperature mold, secondary shrinkage due to crystallization during use becomes a problem. From the background as described above, a resin having a high melting point of 280 ° C. or higher, low water absorption, and easy moldability is required. In the copolymer polyamide of the present invention, a specific amount of 11 nylon is copolymerized with 6T nylon. In addition to having a high melting point and low water absorption, Tc1 can be kept low, and the processability of injection molding can be greatly improved. In addition, when considering the expansion of 6T nylon to automobile parts, not only molding processability and low water absorption are required, but also heat aging resistance to the temperature in the engine room and gasoline to prevent volatilization of fuel. Barrier properties are important. So far, an example of copolymerizing 12 nylon with 6T nylon has been reported, but 12 nylon has a smaller amount of amide bonds than 11 nylon, and it is considered that hydrogen bonds between amide bonds provide a shielding effect on gas components. And it is disadvantageous for the gasoline barrier property. In addition, when 11 nylon has a zigzag structure, it is easier to form hydrogen bonds than 12 nylon and easily forms hydrogen bonds, whereas 12 nylon is difficult to take hydrogen bonds and its hydrogen bondability is weak. . The improvement of hydrogen bonding property is preferable from the viewpoint of heat aging resistance and gasoline barrier property because it improves the glass transition temperature and the shielding effect of gasoline components. From the above, 11 nylon component is a copolymer component superior to 12 nylon component, and so far, 11 nylon is copolymerized with 6T nylon and 280 ° C or higher. No specific copolyamide having a melting point of 5 has been reported.

  Examples of the catalyst used for producing the copolymerized polyamide of the present invention include phosphoric acid, phosphorous acid, hypophosphorous acid or a metal salt, ammonium salt and ester thereof. Specific examples of the metal species of the metal salt include potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, and antimony. As the ester, ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, octadecyl ester, decyl ester, stearyl ester, phenyl ester and the like can be added. Moreover, it is preferable to add sodium hydroxide from the viewpoint of improving the melt residence stability.

  The relative viscosity (RV) of the copolymerized polyamide of the present invention measured at 20 ° C. in 96% concentrated sulfuric acid is 0.4 to 4.0, preferably 1.0 to 3.5, more preferably 1.5 to 3.0. Examples of a method for setting the relative viscosity of the polyamide within a certain range include a means for adjusting the molecular weight.

  In the polyamide of the present invention, the terminal group amount and the molecular weight of the polyamide can be adjusted by a method of polycondensation by adjusting the molar ratio of the amino group amount to the carboxyl group or a method of adding a terminal blocking agent. When polycondensation is performed at a constant ratio of the amino group amount to the carboxyl group, the molar ratio of all diamines to all dicarboxylic acids used is diamine / dicarboxylic acid = 1.00 / 1.05 to 1.05 / It is preferable to adjust to the range of 1.00.

  Examples of the timing for adding the end capping agent include raw material charging, polymerization initiation, polymerization late, and polymerization termination. The end capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the amino group or carboxyl group at the end of the polyamide, but acid anhydrides such as monocarboxylic acid or monoamine, phthalic anhydride, Monoisocyanates, monoacid halides, monoesters, monoalcohols and the like can be used. Examples of the end capping agent include aliphatic monoacids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid. Alicyclic monocarboxylic acids such as carboxylic acid and cyclohexanecarboxylic acid, benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, phenylacetic acid and other aromatic monocarboxylic acids, maleic anhydride Acid, phthalic anhydride, acid anhydrides such as hexahydrophthalic anhydride, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, etc. Aliphatic monoamines, Examples thereof include alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine. Among these, hexahydrophthalic anhydride is most preferable because it is not colored and has high reactivity as a terminal blocking agent.

  The acid value and amine value of the copolymerized polyamide of the present invention are preferably 0 to 200 eq / ton, more preferably 0 to 100 eq / ton. When the terminal functional group is 200 eq / ton or more, not only gelation and deterioration are promoted during melt residence, but also problems such as coloring and hydrolysis are caused in the use environment. On the other hand, when compounding a reactive compound such as glass fiber or maleic acid-modified polyolefin, the acid value and / or amine value is preferably 5 to 150 eq / ton, more preferably, in accordance with the reactivity and reactive group. 100 to 150 eq / ton. Examples of the method for setting the acid value and / or the amine value within a certain range include a means for blending a viscosity modifier such as monocarboxylic acid.

  Various conventional additives for polyamide can be used for the copolymerized polyamide of the present invention. Additives include fibrous reinforcements, fillers, stabilizers, impact modifiers, flame retardants, mold release agents, slidability improvers, colorants, plasticizers, crystal nucleating agents, and copolymerized polyamides of the present invention. Are different polyamides, thermoplastic resins other than polyamide, and the like.

  Examples of the fibrous reinforcing material include glass fiber, carbon fiber, metal fiber, ceramic fiber, organic fiber, whisker, etc. Among them, glass fiber is preferable. These fibrous reinforcing materials may be used not only alone but also in combination of several kinds. As the glass fiber used here, chopped strands or continuous filament fibers having a length of 0.1 mm to 100 mm can be used. As the cross-sectional shape of the glass fiber, a glass fiber having a circular cross section and a non-circular cross section can be used. As the cross-sectional shape of the glass fiber, a glass fiber having a non-circular cross-section is preferable from the viewpoint of physical properties. Non-circular cross-sectional glass fibers include those that are substantially oval, substantially oval, and substantially bowl-shaped in a cross section perpendicular to the length direction of the fiber length, and have a flatness of 1.5 to 8. It is preferable. Here, the flatness is assumed to be a rectangle with the smallest area circumscribing a cross section perpendicular to the longitudinal direction of the glass fiber, the length of the long side of the rectangle is the major axis, and the length of the short side is the minor axis. It is the ratio of major axis / minor axis. The thickness of the glass fiber is not particularly limited, but the minor axis is about 1 to 20 μm and the major axis is about 2 to 100 μm. Moreover, the glass fiber becomes a fiber bundle, and the chopped strand shape cut | disconnected by about 1-20 mm of fiber length can use it preferably. The amount of the fibrous reinforcing material added is a maximum of 250 parts by weight, preferably 20 to 150 parts by weight, based on 100 parts by weight of the copolyamide.

  As fillers (fillers), reinforcing fillers, conductive fillers, magnetic fillers, flame retardant fillers, thermal conductive fillers and the like are listed according to purpose. Specifically, glass beads, glass flakes, glass balloons, silica, talc , Kaolin, wollastonite, mica, alumina, hydrotalcite, montmorillonite, graphite, carbon nanotube, fullerene, zinc oxide, zinc oxide, indium oxide, tin oxide, iron oxide, titanium oxide, magnesium oxide, aluminum hydroxide, water Examples include magnesium oxide, red phosphorus, calcium carbonate, potassium titanate, lead zirconate titanate, barium titanate, aluminum nitride, boron nitride, zinc borate, aluminum borate, barium sulfate, and magnesium sulfate. These fillers may be used not only alone but also in combination of several kinds. The addition amount of the filler is a maximum of 250 parts by weight, preferably 20 to 150 parts by weight with respect to 100 parts by weight of the copolyamide. Moreover, in order to improve the affinity with the polyamide resin, the fibrous reinforcing material and the filler are preferably used in combination with a coupling agent-treated or coupling agent. As the coupling agent, a silane coupling agent is used. Any of titanate coupling agents and aluminum coupling agents may be used, and among them, aminosilane coupling agents and epoxysilane coupling agents are particularly preferable.

  Stabilizers include organic antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, heat stabilizers, light stabilizers such as hindered amines, benzophenones, and imidazoles. Examples include ultraviolet absorbers, metal deactivators, and copper compounds. Copper compounds include cuprous chloride, cuprous bromide, cuprous iodide, cupric chloride, cupric bromide, cupric iodide, cupric phosphate, cupric pyrophosphate, Copper salts of organic carboxylic acids such as copper sulfide, copper nitrate, and copper acetate can be used. Further, as a component other than the copper compound, an alkali metal halide compound is preferably contained. Examples of the alkali metal halide compound include lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, bromide. Examples thereof include sodium, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide and the like. These stabilizers may be used not only alone but also in combination of several kinds.

  The copolymer polyamide of the present invention may be polymer blended with a polyamide having a composition different from that of the copolymer polyamide of the present invention. The polyamide having a composition different from that of the copolymerized polyamide of the present invention is not particularly limited, but polycaproamide (nylon 6), polyundecanamide (nylon 11), polydodecanamide (nylon 12), polytetramethylene adipamide (Nylon 46), polyhexamethylene adipamide (nylon 66), polymetaxylylene adipamide (nylon MXD6), polyparaxylylene adipamide (nylon PXD6), polytetramethylene sebacamide (nylon 410), Polyhexamethylene sebamide (nylon 610), polydecamethylene adipamide (nylon 106), polydecamethylene sebamide (nylon 1010), polyhexamethylene dodecamide (nylon 612), polydecamethylene dodecamide (nylon) 1012), Polyhe Samethylene terephthalamide (nylon 6T), polyhexamethylene isophthalamide (nylon 6I), polytetramethylene terephthalamide (nylon 4T), polypentamethylene terephthalamide (nylon 5T), poly-2-methylpentamethylene terephthalamide (nylon) M-5T), polyhexamethylene hexahydroterephthalamide (nylon 6T (H)), poly-2-methyl-octamethylene terephthalamide, polynonamethylene terephthalamide (nylon 9T), polydecamethylene terephthalamide (nylon 10T), Polyundecamethylene terephthalamide (nylon 11T), Polydodecamethylene terephthalamide (nylon 12T), Polybis (3-methyl-4-aminohexyl) methane terephthalamide ( Iron PACMT) polybis (3-methyl-4-aminohexyl) methane isophthalamide (nylon PACMI), polybis (3-methyl-4-aminohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-amino) Hexyl) methanetetradecamide (nylon PACM14), polyalkyl ether copolymerized polyamide or the like, or these copolymerized polyamides may be used alone or in combination. Among these, nylon 66, nylon 6T66, and the like are preferably polymer blended in order to improve the crystallization speed.

  A thermoplastic resin other than polyamide may be added to the copolymerized polyamide of the present invention. Polymers other than polyamide include polyphenylene sulfide (PPS), liquid crystal polymer (LCP), aramid resin, polyetheretherketone (PEEK), polyetherketone (PEK), polyetherimide (PEI), thermoplastic polyimide, polyamideimide (PAI), polyether ketone ketone (PEKK), polyphenylene ether (PPE), polyether sulfone (PES), polysulfone (PSU), polyarylate (PAR), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene Phthalate, polycarbonate (PC), polyoxymethylene (POM), polypropylene (PP), polyethylene (PE), polymethylpentene (TPX), polystyrene ( S), polymethyl methacrylate, acrylonitrile - styrene copolymer (AS), acrylonitrile - butadiene - like styrene copolymer (ABS). When the compatibility is poor, it is important to add a compatibilizing agent such as a reactive compound or a block polymer, or to modify a polymer other than polyamide (particularly acid modification is preferred). These thermoplastic resins can be blended in a molten state by melt kneading. However, the thermoplastic resin may be made into a fiber or particle and dispersed in the copolymerized polyamide of the present invention.

  As impact modifiers, ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene- Polyolefin resins such as methacrylic acid ester copolymer, ethylene vinyl acetate copolymer, styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene -Polytetramethylene glycol, polycaprolactone, or poly (polyethylene glycol) as a hard segment made of vinyl polymer resin such as styrene copolymer (SIS), acrylate copolymer, polybutylene terephthalate or polybutylene naphthalate. Polyester block copolymer in which the ball sulfonate diol as a soft segment, a urethane elastomer, silicone rubber, fluorinated rubber, and the like polymer particles having a core-shell structure constituted from two different polymers.

  When a thermoplastic resin other than the polyamide resin in the present invention and an impact resistance improving material are added to the copolymerized polyamide of the present invention, it is preferable that a reactive group capable of reacting with the polyamide is copolymerized. Examples of the functional group include a group capable of reacting with an amino group, a carboxyl group and a main chain amide group which are terminal groups of the polyamide resin. Specific examples include a carboxylic acid group, an acid anhydride group, an epoxy group, an oxazoline group, an amino group, and an isocyanate group, and among them, the acid anhydride group is most excellent in reactivity.

  As a flame retardant, a combination of a halogen flame retardant and antimony is good, and as a halogen flame retardant, brominated polystyrene, brominated polyphenylene ether, brominated bisphenol type epoxy polymer, brominated styrene maleic anhydride polymer, Brominated epoxy resins, brominated phenoxy resins, decabromodiphenyl ether, decabromobiphenyl, brominated polycarbonate, perchlorocyclopentadecane, brominated cross-linked aromatic polymers, etc. are preferred. Antimony compounds include antimony trioxide and antimony pentoxide. Sodium antimonate and the like are preferable. Among these, a combination of dibromopolystyrene and antimony trioxide is preferable from the viewpoint of thermal stability. Non-halogen flame retardants include melamine cyanurate, red phosphorus, phosphinic acid metal salts, and nitrogen-containing phosphoric acid compounds. In particular, a combination of a phosphinic acid metal salt and a nitrogen-containing phosphoric acid compound is preferable. Examples of the nitrogen-containing phosphoric acid compound include melamine, a condensate of melamine such as melam and melon, and a reactive organism of polyphosphoric acid or those. A mixture of At that time, addition of a hydrotalcite-based compound is preferable for preventing metal corrosion of a mold or the like.

  Examples of the release agent include long chain fatty acids or esters thereof, metal salts, amide compounds, polyethylene wax, silicon, polyethylene oxide, and the like. The long chain fatty acid preferably has 12 or more carbon atoms, and examples thereof include stearic acid, 12-hydroxystearic acid, behenic acid, and montanic acid. Partial or total carboxylic acid is esterified with monoglycol or polyglycol. Or a metal salt may be formed. Examples of the amide compound include ethylene bisterephthalamide and methylene bisstearyl amide. These release agents may be used alone or as a mixture.

  Examples of the sliding property improving material include high molecular weight polyethylene, acid-modified high molecular weight polyethylene, fluorine resin powder, molybdenum disulfide, silicon resin, silicon oil, zinc, graphite, mineral oil, and the like. The slidability-improving material can be added as long as the properties of the resin are not impaired.

  The copolymer polyamide of the present invention can be produced by a conventionally known method. For example, (a) an aliphatic diamine having 4 to 12 methylene chains as a raw material monomer, terephthalic acid, and (b) 11-aminoundecanoic acid or undecanactam which is a raw material monomer of the component, and (c) a structural unit obtained from an equivalent molar salt of diamine and dicarboxylic acid other than the structural unit of (a) if necessary, or (b) It can be easily synthesized by co-condensation reaction of aminocarboxylic acids or lactams other than the structural units. The order of the copolycondensation reaction is not particularly limited, and all the raw material monomers may be reacted at once, or a part of the raw material monomers may be reacted first, followed by the remaining raw material monomers. The polymerization method is not particularly limited, but from raw material charging to polymer production may proceed in a continuous process, and after producing an oligomer once, the polymerization is advanced by an extruder or the like in another process, or the oligomer is solidified. A method of increasing the molecular weight by phase polymerization may be used. By adjusting the charging ratio of the raw material monomer, the proportion of each structural unit in the copolymerized polyamide to be synthesized can be controlled.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, the measured value described in the Example is measured by the following method.

(1) Relative viscosity 0.25 g of polyamide resin was dissolved in 25 ml of 96% sulfuric acid and measured at 20 ° C. using an Ostwald viscometer.

(2) Terminal amino group amount 0.2 g of polyamide resin was dissolved in 20 ml of m-cresol and titrated with a 0.1 mol / l hydrochloric acid ethanol solution. Cresol red was used as the indicator. Expressed as equivalents (eq / ton) in 1 ton of resin.

(3) Melting point (Tm) and temperature rising crystallization temperature (Tc1)
10 mg of the polyamide dried under reduced pressure at 105 ° C. for 15 hours was weighed in an aluminum pan (TA Instruments, product number 900793.901), sealed with an aluminum lid (TA Instruments, product number 900794.901), and measured. After preparing the sample, use a differential scanning calorimeter DSCQ100 (manufactured by TA INSTRUMENTS) to raise the temperature from room temperature to 20 ° C./min, hold at 350 ° C. for 3 minutes, take out the measurement sample pan, soak in liquid nitrogen, and quench rapidly I let you. Thereafter, the sample was taken out from the liquid nitrogen, allowed to stand at room temperature for 30 minutes, and then heated again from room temperature at 20 ° C./minute using a differential scanning calorimeter DSCQ100 (manufactured by TA INSTRUMENTS) and held at 350 ° C. for 3 minutes. . At that time, the peak temperature of the crystallization exotherm during the temperature rise was defined as the temperature rise crystallization temperature (Tc1), and the peak temperature of the endotherm due to melting was defined as the melting point (Tm).

(4) Formability Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature was set to the melting point of the resin + 20 ° C. As the mold, a mold for producing a flat plate having a length of 100 mm, a width of 100 mm, and a thickness of 1 mm was used. Mold temperature was set to 140 ° C., molding was performed at an injection speed of 50 mm / sec, a holding pressure of 30 MPa, an injection time of 10 seconds, and a cooling time of 10 seconds. The moldability was evaluated according to the following criteria. .
○: Significant decomposition of the resin is not observed, and a molded product can be obtained without any problem.
X: Foaming due to decomposition is accompanied at the time of molding, or the releasability is insufficient, and the molded product sticks to the mold or deforms.

(5) Heat aging resistance For the heat aging resistance test, a compound obtained by compounding 0.02 part of cupric bromide and 0.15 part of potassium iodide to 100 parts of polyamide, and using an ISO with an injection molding machine. A dumbbell-shaped test piece based on the above was prepared. The molded product was subjected to a heat aging test for 1000 hours in a 160 ° C. gear oven, and a tensile test was performed according to ISO 527. The quality of heat aging resistance was evaluated according to the following criteria.
○: Tensile strength or tensile yield strength retention after 1000 hours at 160 ° C. is 95% or more ×: Tensile strength or tensile yield strength retention after 1000 hours at 160 ° C. is less than 95%

(6) Gasoline barrier property For the evaluation of gasoline barrier property, a fuel permeability test by the cup method was conducted. 4.6 g of fuel composed of 45/45/10 vol% of isooctane / toluene / ethanol was added to the cup. For the fuel permeability measurement, the polyamide of the present invention prepared on a film having a thickness of 100 μm by a heat press was used. The obtained film was placed on the cup to which the fuel was added so as not to contact the fuel (vapor phase method). Airtightness was maintained so that the fuel would not volatilize except from permeation through the film. The measurement was performed with a permeation area of 1.133 × 10 ⁻³ m ² , a test temperature of 60 ° C., and a test time of 240 hours, and the weight change before and after the measurement was measured. In addition, a blank experiment for taking into account the water absorption / release characteristics of the sample was performed and corrected to calculate the fuel permeation amount. Gasoline barrier properties were evaluated based on the following criteria.
○: Weight reduction amount is less than 100 mg ×: Weight reduction amount is 100 mg or more

(7) Saturated water absorption For evaluation of the saturated water absorption, a flat plate having a length of 100 mm, a width of 100 mm, and a thickness of 1 mm was prepared, immersed in 80 ° C. hot water, and obtained from the following formula.
Saturated water absorption (%) = {(weight at time of saturated water absorption−weight at time of drying) / weight at time of drying} × 100

<Example 1>
1.99 kg of 1,4-tetramethylenediamine, 9.40 kg of terephthalic acid, 11.40 kg of 11-aminoundecanoic acid, 40 g of acetic acid and 17.0 kg of ion-exchanged water as terminal regulators were charged into a 50 liter autoclave from atmospheric pressure. The pressure was increased to 0.05 MPa with N ₂ , the pressure was released, and the pressure was returned to normal pressure. This operation was performed 3 times, N ₂ substitution was performed, and then uniform dissolution was performed at 135 ° C. and 0.3 MPa with stirring. Thereafter, the solution was continuously supplied by a liquid feed pump, heated to 240 ° C. with a heating pipe, and heated for 1 hour. Thereafter, the reaction mixture was supplied to a pressure reaction can, heated to 290 ° C., and a part of water was distilled off so as to maintain the can internal pressure at 3 MPa to obtain a low-order condensate. Thereafter, the low-order condensate containing moisture was directly transferred into a twin-screw extruder (screw diameter 37 mm, L / D = 60, barrel temperature (° C.) 350/350/325/325/325 / while maintaining the solution state. 325/325/325/325/320 advances rear vent, eighth zone vacuum vent, rotational speed 100 rpm, oligomer feed amount 8 kg / hr, the exhaust is supplied to the _{N 2} purge), polycondensation under melt copolymerization Polyamide was obtained. Table 1 shows the charge ratio of raw material monomers and the characteristics of the obtained copolymer polyamide.

<Examples 2-8, Comparative Examples 1-5>
Autoclave with 50 liters of aliphatic diamine having 3 to 12 carbon atoms, terephthalic acid, 11-aminoundecanoic acid or adipic acid, catalyst, terminal adjusting agent and acetic acid and ion-exchanged water in the proportion of mol% described in Table 1 The polycondensation was advanced in the same manner as in Example 1 to obtain a copolymerized polyamide. The properties of the obtained copolymer polyamide are shown in Table 1.

  As is apparent from Table 1, the copolymer polyamides of Examples 1 to 8 highly satisfy all three properties of moldability, heat aging resistance, and gasoline barrier properties. Especially, when the balance of a water absorption and a moldability is considered, it can be said that Examples 3-5 are the most preferable. On the other hand, the copolymerized polyamides of Comparative Examples 1 to 3 in which 11 nylon is not copolymerized cannot be polymerized (Comparative Example 1) or have poor moldability even if polymerized (Comparative Examples 2 and 3). Comparative Example 4 as a copolymer component is inferior in heat aging resistance and gasoline barrier property. Further, Comparative Example 5 using an aliphatic diamine having a methylene chain number of 3 did not satisfy the moldability.

In the copolymerized polyamide of the present invention, 11 nylon is copolymerized at a specific ratio to a structural unit obtained from an equimolar molar salt of an aliphatic diamine having 4 to 12 methylene chains as a main component and terephthalic acid. While taking advantage of properties such as a high melting point of 280 ° C. or higher, mechanical properties, and slidability, low water absorption, moldability, heat aging resistance, and gasoline barrier properties can be highly satisfied. Therefore, the copolymerized polyamide of the present invention can be suitably used as a molding material or a sliding material for automobiles and electronic parts.

Claims (3)

  (A) 50-97 mol% of structural units obtained from an equimolar salt of an aliphatic diamine having 4-12 methylene chains and terephthalic acid, and (b) a composition obtained from 11-aminoundecanoic acid or undecanactam Copolymer polyamide comprising 50 to 3 mol% of units.   The aliphatic diamine as component (a) is 1,4-tetramethylenediamine, 1,5-pentamethylenediamine, 1,9-nonamethylenediamine, 1,11-undecamethylenediamine, 1,12-dodecamethylenediamine. The copolymerized polyamide according to claim 1, wherein the polyamide is selected from the group consisting of:   The copolyamide according to claim 1 or 2, wherein the copolyamide has a melting point (Tm) of 280 to 320 ° C and a temperature rising crystallization temperature (Tc1) of 90 to 140 ° C.