JP2015101675A - Polyamide molded body and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide resin having excellent heat durability and color.SOLUTION: The present invention provides a polyamide molded body formed by heating and molding a polyamide resin at 330°C or below in a non-oxidizing atmosphere. The polyamide resin is obtained by a polycondensation reaction between a dicarboxylic acid compound and a diamine compound. The dicarboxylic acid compound contains terephthalic acid, and the diamine compound contains aliphatic diamine having 12 carbon atoms. The polyamide resin satisfies (1) and (2) in the following: (1) the melting point is 265 to 300°C; and (2) the molar ratio between aliphatic diamine having 10 carbon atoms and aliphatic diamine having 12 carbon atoms contained in the diamine compound satisfies (aliphatic diamine having 10 carbon atoms):(aliphatic diamine having 12 carbon atoms)=0:100 to 70:30.

Description

  The present invention relates to a polyamide molded body and a method for producing the same.

  Polyamide resins are widely used as clothing, industrial material fibers, engineering plastics and the like because of their excellent properties and ease of melt molding. In recent years, polyamide resins used in the fields of electric / electronic parts, automobile parts, reflective materials, and the like have been demanded to have better physical properties and functions.

  Patent Document 1 includes a dicarboxylic acid unit (a) containing 60 to 100 mol% of a terephthalic acid unit, and a diamine unit (b) containing 60 to 100 mol% of an aliphatic alkylenediamine unit having 6 to 18 carbon atoms. There is disclosed a polyamide composition obtained by blending 0.1 to 120 parts by weight of an inorganic filler (B) having an average particle diameter of 2 μm or less with respect to 100 parts by weight of polyamide (A). The polyamide composition is excellent in heat resistance at the time of moisture absorption, dimensional stability, and surface smoothness, and is said to be a suitable material for an LED reflector.

  Patent Document 2 discloses 30 to 95% by weight of a semi-aromatic polyamide in which the ratio of aromatic monomers in all monomer components is 20 mol% or more, and potassium titanate fiber and / or wollastonite 5 to 70% by weight. %, And a resin composition for a reflector containing the same. The reflective plate resin composition is said to exhibit good physical properties such as reflectance, whiteness, and mechanical strength while exhibiting useful physical properties of the polyamide resin.

JP 2000-204244 A JP 2002-294070 A

  Parts such as reflectors are often used in a high temperature environment, and it is desired to develop a polyamide resin molded article having excellent heat-resistant hue that hardly changes color under high temperature conditions.

  However, even when the polyamide resin described in Patent Document 1 is used, for example, the heat resistant hue of the material itself for maintaining the luminance (high color resistance under heating conditions) when the LED is used at high temperatures due to high luminance and high output. There is a problem that the property is not necessarily sufficient. In addition, the molded body using the resin composition described in Patent Document 2 also has a problem in that a decrease in luminance due to a decrease in reflectance due to discoloration of the resin itself cannot be suppressed during high temperature use.

  Then, an object of this invention is to provide the polyamide molded object excellent in heat-resistant hue, and its manufacturing method.

  The present invention is a polyamide molded body obtained by heating and molding a polyamide resin at a temperature of 330 ° C. or less and in a non-oxidizing atmosphere, and the polyamide resin is formed by a polycondensation reaction between a dicarboxylic acid compound and a diamine compound. A polyamide molded article that is obtained and is a polyamide resin satisfying the following (1) and (2), wherein the dicarboxylic acid compound contains terephthalic acid, and the diamine compound contains an aliphatic diamine having 12 carbon atoms; ) Melting point is 265 to 300 ° C. (2) The molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is aliphatic diamine having 10 carbon atoms: carbon The aliphatic diamine of formula 12 = 0: 100 to 70:30.

  ADVANTAGE OF THE INVENTION According to this invention, the polyamide molded object excellent in heat-resistant hue and its manufacturing method can be provided.

  The present invention is a polyamide molded body obtained by heating and molding a polyamide resin at a temperature of 330 ° C. or less and in a non-oxidizing atmosphere, and the polyamide resin is formed by a polycondensation reaction between a dicarboxylic acid compound and a diamine compound. A polyamide molded article that is obtained and is a polyamide resin satisfying the following (1) and (2), wherein the dicarboxylic acid compound contains terephthalic acid, and the diamine compound contains an aliphatic diamine having 12 carbon atoms; ) Melting point is 265 to 300 ° C. (2) The molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is aliphatic diamine having 10 carbon atoms: carbon The aliphatic diamine of formula 12 = 0: 100 to 70:30. The polyamide molded body having such a configuration is excellent in heat resistant hue (discoloration resistance under heating conditions).

  As described above, when a conventional polyamide molded body is used for, for example, an LED reflector, there is a problem in that a decrease in luminance due to a decrease in reflectance due to discoloration of the resin itself cannot be suppressed during high temperature use. The present inventors assume that the cause of deterioration of the discoloration resistance when used in the atmosphere is due to the deterioration in the molded body, and the cause of the generation of deterioration is the thermal deterioration during molding It was thought that this was due to oxidative degradation. Therefore, the inventors have found that the above-described deterioration can be suppressed by molding at a low temperature and molding under non-oxidizing conditions, and have completed the present invention.

  The details of the deterioration mechanism are unknown, but are considered as follows. In addition, this invention is not restrained at all by the following mechanism.

  In a molding method such as injection molding, the polyamide resin is heated and melted to a temperature higher than the melting point in order to reduce the viscosity of the polyamide resin during molding. However, the polyamide is easily decomposed by heat at the time of heat melting and oxygen in the atmosphere. LED reflectors and the like are under conditions of use exceeding 100 ° C. However, when the polyamide molded body is exposed to such a high temperature, the decomposition product of polyamide generated by heating during molding is caused by heat or atmospheric oxygen. It deteriorates and the molded body is easily colored.

  On the other hand, according to the structure of this invention, since the heat | fever at the time of shaping | molding and generation | occurrence | production of the polyamide decomposition product by oxygen are reduced, it is thought that a heat resistant hue improves.

  The polyamide molded body of the present invention is a molded product formed by molding a polyamide resin. Hereinafter, the polyamide resin will be described in detail. In the present invention, the “polyamide resin” is not limited to a form in which the total amount (100% by weight) is a resin, and is used at the time of polycondensation as other components other than the polyamide resin within the range in which the above performance is maintained. The catalyst and additive etc. which were prepared may be included. That is, the polyamide resin composition containing a polyamide resin and an additive is also collectively referred to as a polyamide resin in the present invention. The content of the polyamide resin is preferably 40 to 100% by weight, more preferably 60 to 100% by weight, based on the whole. As other components other than the polyamide resin, phosphorus compounds are preferable, and known stabilizers, fillers, additives and the like are included as necessary.

  The polyamide resin of the present invention satisfies the following (1) and (2); (1) the melting point is 265 to 300 ° C., (2) an aliphatic diamine having 10 carbon atoms in the diamine compound, and 12 carbon atoms The molar ratio with respect to the aliphatic diamine is C10 aliphatic diamine: C12 aliphatic diamine = 0: 100 to 70:30.

  In a molding method such as injection molding, the polyamide resin is heated and melted above its melting point in order to reduce the viscosity of the polyamide resin during molding. Under the condition (1), if the melting point of the polyamide resin exceeds 300 ° C., it is necessary to increase the temperature applied during melt molding, and the possibility of thermal degradation of the polyamide resin increases. Moreover, since it is inferior to solder heat resistance as it is less than 265 degreeC, it is unpreferable. From the viewpoint that the heating and melting temperature can be further lowered, thermal deterioration can be suppressed, and the heat resistant hue can be further improved, the melting point of the polyamide resin is more preferably 265 ° C. or higher and lower than 280 ° C. The melting point of the polyamide resin is controlled, for example, by controlling the molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound (2) below.

  In the condition (2), the molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is an aliphatic diamine having 10 carbon atoms: an aliphatic diamine having 12 carbon atoms = 0: 100 to 70:30. The content molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms is in such a range, so there is no need to increase the temperature applied during melt molding, and the resin can be thermally deteriorated. The heat resistance hue is improved.

  The polyamide resin is obtained by a polycondensation reaction between a dicarboxylic acid compound and a diamine compound. Hereinafter, the dicarboxylic acid compound and the diamine compound will be described.

[Dicarboxylic acid compound]
The dicarboxylic acid compound used as a raw material for the polyamide resin of the present invention contains terephthalic acid from the viewpoint of heat resistance and mechanical strength. The content of terephthalic acid in the dicarboxylic acid compound is not particularly limited, but is preferably 50 mol% or more (upper limit 100 mol%), more preferably 75 mol% or more (upper limit 100 mol%), 100 More preferably, it is mol%.

  Specific examples of dicarboxylic acids other than terephthalic acid include, for example, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, and 2,2-dimethylglutaric acid. , 3,3-diethylsuccinic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid and other aliphatic dicarboxylic acids; 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, etc. Cycloaliphatic dicarboxylic acid; isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxy Diacetic acid, diphenic acid, 4,4′-oxydibenzoic acid, diphenylmethane-4,4′-dica Bon acid, diphenylsulfone-4,4'-dicarboxylic acid, and aromatic dicarboxylic acids such as 4,4'-biphenyl dicarboxylic acid. These dicarboxylic acids other than terephthalic acid can be used alone or in combination of two or more.

  If necessary, a small amount of a polyvalent carboxylic acid such as trimellitic acid, trimesic acid or pyromellitic acid may be used in combination.

[Diamine compound]
In the present invention, the diamine compound essentially contains an aliphatic diamine having 12 carbon atoms from the viewpoint of adjusting the melting point. The aliphatic diamine having 12 carbon atoms is more preferably 30 to 100 mol% in the diamine compound.

  Examples of the aliphatic diamine having 12 carbon atoms include 1,12-diaminododecane, 2-methyl-1,11-undecanediamine, and 2,3-dimethyl-1,10-decanediamine. Among these, 1,12-diaminododecane is preferable from the viewpoint of high crystallinity, low water absorption, economy, and the like.

  Even when the diamine compound is composed only of an aliphatic diamine having 12 carbon atoms, since the polyamide resin can be molded at a temperature of 330 ° C. or lower, the resin deterioration is suppressed. When a polyamide resin is produced by mixing a group diamine, the melting point of the polyamide resin is lowered. The melting point is lowered because the crystallinity of the aliphatic diamine having 12 carbons is disturbed when the aliphatic diamine having 10 carbons is mixed with the aliphatic diamine having 12 carbons. Due to such a melting point reduction, molding at a lower temperature is possible, and resin degradation can be suppressed.

  From such a viewpoint, the diamine compound optionally includes an aliphatic diamine having 10 carbon atoms, and preferably includes an aliphatic diamine having 10 carbon atoms. In this case, since the melting point lowering effect of the aliphatic diamine having 10 carbon atoms appears remarkably, the aliphatic diamine having 10 carbon atoms: the aliphatic diamine having 12 carbon atoms = 20: 80 to 70:30 (molar ratio). It is preferable that the heat-resistant hue is further improved, so that the aliphatic diamine having 10 carbon atoms: the aliphatic diamine having 12 carbon atoms = 30: 70 to 70:30 (molar ratio) is more preferable, and the carbon number is 10 Of aliphatic diamine: aliphatic diamine having 12 carbon atoms = 30: 70 to 60:40 (molar ratio).

  The melting point of the polyamide resin, which is a polycondensation resin of an aliphatic diamine having 10 carbon atoms and terephthalic acid, is about 320 ° C., and the amount of the aliphatic diamine having 10 carbon atoms is an aliphatic diamine and carbon having 10 carbon atoms. When it exceeds 70 mol% with respect to the total amount of the aliphatic diamine of several 12, melting | fusing point of polycondensation resin with a terephthalic acid exceeds 300 degreeC, and the effect of this invention cannot be acquired.

  Examples of the aliphatic diamine having 10 carbon atoms include 1,10-diaminodecane, 5-methyl-1,9-nonanediamine, and 3,5-dimethyl-1,8-octanediamine. Among these, 1,10-diaminodecane is preferable in terms of high crystallinity, low water absorption, economical efficiency, and the like.

  The total amount of the aliphatic diamine having 12 carbon atoms and the aliphatic diamine having 10 carbon atoms is preferably 90 mol% or more, more preferably 100 mol%, in the diamine compound from the viewpoint of the heat resistant hue.

  The diamine compound used as the raw material of the polyamide resin of the present invention may contain other diamine compounds other than the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms. The addition amount of the diamine compound other than the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms is preferably 10 mol% or less, and 0 mol% in the diamine compound from the viewpoint of the heat resistant hue. It is more preferable.

  As another diamine compound, a C4-C25 aliphatic alkylenediamine compound is mentioned suitably.

  Specific examples of the aliphatic alkylene diamine having 4 to 25 carbon atoms include, for example, 1,4-butanediamine, 1,6-hexanediamine (hexamethylenediamine), 1,7-heptanediamine, and 1,8-octanediamine. 1,9-nonanediamine, 1,11-undecanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine 2,4,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, and the like. These aliphatic alkylenediamines having 4 to 25 carbon atoms can be used alone or in combination of two or more.

  Specific examples of diamines other than aliphatic alkylene diamines having 4 to 25 carbon atoms include, for example, ethylenediamine, propanediamine; cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, 1 , 3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, norbornane dimethanamine, tricyclodecane dimethanamine, and other alicyclic diamines; paraphenylenediamine, metaphenylenediamine, xylylenediamine, 4,4 Examples thereof include aromatic diamines such as' -diaminodiphenyl sulfone and 4,4'-diaminodiphenyl ether. These diamines other than aliphatic alkylene diamine having 4 to 25 carbon atoms can be used alone or in combination of two or more. The term xylylenediamine includes three isomers, orthoxylylenediamine, metaxylylenediamine (MXDA), and paraxylylenediamine (PXDA).

[Phosphorus compound concentration (unit: μmol / g) / terminal amino group concentration (unit: μmol / g)]
The polyamide resin of the present invention has a ratio (phosphorus compound concentration / terminal amino group) of the phosphorus compound concentration (unit: μmol / g) contained in the polyamide resin and the terminal amino group concentration (unit: μmol / g) of the polyamide resin. Concentration) is preferably 0.2 to 1.0, and more preferably 0.5 to 1.0. When the phosphorus compound concentration / terminal amino group concentration is preferably 0.2 or higher, more preferably 0.5 or higher, the heat resistant hue is significantly improved by the phosphorus compound. On the other hand, when the phosphorus compound concentration / terminal amino group concentration is 1.0 or less, it is possible to reduce gas generation and gelation phenomenon associated with side reactions during heating and melting. The phosphorus compound concentration / terminal amino group concentration is preferably 0.5 to 0.9. Since the molded product of the present invention is excellent in heat resistant hue, even when the phosphorus compound concentration / terminal amino group concentration is relatively low (the phosphorus compound concentration / terminal amino group concentration is less than 0.5), the heat resistant hue is obtained. Can be improved. Therefore, the amount of phosphorus compound to be added can be reduced.

  The phosphorus compound contained in the polyamide resin is caused by the phosphorus compound at the time of polycondensation. For this reason, the polyamide resin of the present application preferably contains a phosphorus compound.

  The phosphorus compound concentration / terminal amino group concentration in the polyamide resin of the present invention controls the amount of the phosphorus compound added, the ratio of the dicarboxylic acid compound and diamine compound used as the raw material of the polyamide resin, or the polyamide resin concentration. It can be controlled by adjusting the degree of polymerization and the like.

  For example, the terminal amino group concentration becomes relatively low by increasing the charging ratio of the dicarboxylic acid compound to the diamine compound. Further, by increasing the degree of polymerization of the polyamide resin, both the terminal amino group concentration and the terminal carboxyl group concentration are lowered. In the present invention, as long as the phosphorus compound concentration / terminal amino group concentration is within a predetermined range, the charging ratio of the dicarboxylic acid compound and the diamine compound, the degree of polymerization of the polyamide resin, and the like are not particularly limited. For example, after setting the necessary degree of polymerization so as to match the use of the polyamide resin, it is possible to determine the charging ratio of the dicarboxylic acid compound or the diamine compound according to the amount of the phosphorus compound to be added.

  The phosphorus compound contained in the polyamide resin is not particularly limited. For example, hypophosphite, phosphite, phosphate, hypophosphorous acid, phosphorous acid, phosphoric acid, phosphate ester, polymetaphosphoric acid, polyphosphoric acid, phosphine oxide, or phosphonium halogen compound It is done. These are preferable because they are suitably used as a catalyst for the production of a low-order condensate described later. Furthermore, at least 1 selected from the group consisting of hypophosphite, phosphite, phosphate, hypophosphorous acid, phosphorous acid, and phosphoric acid from the viewpoint of resistance to discoloration under heating conditions Species are more preferable, and at least one selected from the group consisting of hypophosphite, phosphate, hypophosphorous acid, and phosphoric acid is more preferable.

  Examples of hypophosphites include sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, magnesium hypophosphite, aluminum hypophosphite, vanadium hypophosphite, manganese hypophosphite, Examples thereof include zinc hypophosphite, lead hypophosphite, nickel hypophosphite, cobalt hypophosphite, ammonium hypophosphite and the like.

  Examples of the phosphite include potassium phosphite, sodium phosphite, calcium phosphite, magnesium phosphite, manganese phosphite, nickel phosphite, cobalt phosphite and the like.

  Examples of phosphates include sodium phosphate, potassium phosphate, potassium dihydrogen phosphate, calcium phosphate, vanadium phosphate, magnesium phosphate, manganese phosphate, lead phosphate, nickel phosphate, cobalt phosphate, phosphoric acid. Examples include ammonium and diammonium hydrogen phosphate.

  Examples of phosphate esters include monomethyl phosphate ester, dimethyl phosphate ester, trimethyl phosphate, monoethyl phosphate ester, diethyl phosphate ester, triethyl phosphate, propyl phosphate ester, dipropyl phosphate ester, tripropyl phosphate, isopropyl Phosphate ester, diisopropyl phosphate ester, triisopropyl phosphate, butyl phosphate ester, dibutyl phosphate ester, tributyl phosphate, isobutyl phosphate ester, diisobutyl phosphate ester, triisobutyl phosphate, hexyl phosphate ester, dihexyl phosphate ester, Trihexyl phosphate, octyl phosphate, dioctyl phosphate, trioctyl phosphate, 2-ethylhexyl phosphate, di (2-ethylhexyl) phosphate Ter, tri (2-ethylhexyl) phosphate decyl phosphate, didecyl phosphate, tridecyl phosphate, isodecyl phosphate, diisodecyl phosphate, triisodecyl phosphate, stearyl phosphate, distearyl phosphate, tristearyl phosphate Examples include acid, monophenyl phosphate, diphenyl phosphate, triphenyl phosphate, and ethyl octadecyl phosphate.

  Examples of the polymetaphosphoric acid include sodium trimetaphosphate, sodium pentametaphosphate, sodium hexametaphosphate, polymetaphosphoric acid and the like. Examples of polyphosphoric acids include sodium tetrapolyphosphate. Examples of phosphine oxides include hexamethylphosphoramide.

  These phosphorus compounds may be in the form of hydrates.

  Among these phosphorus compounds, sodium hypophosphite or a hydrate thereof, sodium phosphite or a hydrate thereof is preferable.

  In addition, the said phosphorus compound can be used individually or in mixture of 2 or more types.

  The phosphorus compound concentration contained in the polyamide resin of the present invention is preferably 2 to 100 μmol / g, more preferably 5 to 70 μmol / g. When the phosphorus compound concentration is 2 μmol / g or more, it is easy to obtain an effect of improving the heat-resistant hue by the phosphorus compound. On the other hand, when the phosphorus compound concentration is 100 μmol / g or less, side reactions such as gelation hardly occur. The phosphorus compound concentration in the polyamide resin can be measured by a method using an inductively coupled plasma emission spectrometer (ICP-AES), and more specifically, can be measured by the method described in the examples. it can.

  The addition (preparation) of the phosphorus compound to the polyamide resin of the present invention is performed together with the raw material when the low-order condensate is produced as described above, and the produced low-order condensate is impregnated with a solution of the phosphorus compound. There is an example in which solid-phase polymerization or the like is carried out after dispersion by the above means, and there is no particular limitation. In order to obtain the effect of discoloration resistance, it is more preferable to add it when producing a low-order condensate.

Also, the terminal amino group concentration of the polyamide resin of the present invention _([NH 2]) is preferably 20~100μmol / g. When the terminal amino group concentration is 20 μmol / g or more, there is little need to perform the polycondensation reaction at a high temperature for the purpose of increasing the reaction rate of the polycondensation reaction, and the heat resistant hue is less likely to be lowered by the thermal history. On the other hand, when it is 100 μmol / g or less, coloring due to terminal amino groups is small, and a decrease in heat resistant hue (discoloration resistance in a heating environment) is suppressed. The terminal amino group concentration can be measured by a titration method, and more specifically can be measured by the method described in the examples.

  In the polyamide resin of the present invention, the logarithmic viscosity (IV) measured at 25 ° C. at a concentration of 0.5 g / dL in concentrated sulfuric acid is preferably 0.6 to 1.5, and preferably 0.7 to 1 .3 is more preferable. When the IV is 0.6 or more, the content of a component having a low degree of polymerization is small, and the heat resistant hue is further improved, which is preferable. Moreover, since IV is 1.5 or less, there is little deterioration by the heat history at the time of superposition | polymerization, and possibility that the discoloration resistance in a heating environment will fall is low. In addition, IV can be specifically measured by the method as described in the below-mentioned Example.

[Other additive components]
The polyamide resin used for the polyamide molded body may contain additional components other than those described above.

  Examples of the additive component include titanium oxide, titanium dioxide, titanium trioxide, zinc oxide, zirconium oxide, zinc sulfide and other filler materials, glass fibers, carbon fibers and other fiber materials, inorganic powder fillers, and organic powder fillers. Antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphites and their substitutes, copper compounds, etc.), weathering agents (resorcinols, salicylates, benzotriazoles, benzophenones, hindered amines, etc.) ), Mold release agents and lubricants (montanic acid and metal salts thereof, esters thereof, half esters thereof, stearyl alcohol, stearamide, various bisamides, bisureas and polyethylene waxes), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), Dye (Nigrosine ), Crystal nucleating agent (talc, silica, kaolin, clay, etc.), plasticizer (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agent (alkyl sulfate type anionic antistatic agent, polyoxy) Nonionic antistatic agents such as ethylene sorbitan monostearate, betaine amphoteric antistatic agents, etc.), flame retardants (eg, red phosphorus, melamine cyanurate, magnesium hydroxide, aluminum hydroxide and other hydroxides, polyphosphorus) Ammonium acid, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resins or combinations of these brominated flame retardants and antimony trioxide), other polymers (olefins, modified polyolefins, ethylene Methyl acrylate copolymer, ethylene Olefin copolymers such as polyacrylate copolymer, ethylene / propylene copolymer, ethylene-1-butene copolymer, olefin copolymers such as propylene-1-butene copolymer, polystyrene, fluororesin, silicone resin , LCP (Liquid Crystal Polymer, liquid crystal polymer)) and the like.

  The content of the additive component in the polyamide resin (excluding the phosphorus compound) depends on the use and function of the polyamide resin, but is usually 0 to 150 parts by weight with respect to 100 parts by weight of the polyamide resin other than the other additive components. Yes, preferably 0 to 100 parts by weight.

[Molded body]
The molded article of the polyamide resin of the present invention can be obtained by molding a polyamide resin.

  The present invention is also characterized in that the polyamide resin is heated and molded at a temperature of 330 ° C. or lower and in a non-oxidizing atmosphere. “The polyamide resin is heated at a temperature of 330 ° C. or lower” means that the actually measured temperature of the polyamide resin during molding heating is 330 ° C. or lower. For example, in injection molding, it is obtained by measuring the temperature of a polyamide resin in a cylinder of an injection molding machine.

  The polyamide resin of the present application can be molded at a temperature of 330 ° C. or lower even in a molding method such as injection molding that requires heating and melting. Therefore, the molded body is heated at a temperature not lower than the melting point of the polyamide resin and not higher than 330 ° C. It is preferable to form them. The molding temperature is more preferably a temperature from 5 ° C. or higher to 330 ° C. higher than the melting point of the polyamide resin, and even more preferably a temperature from 8 ° C. or higher to 290 ° C. higher than the melting point of the polyamide resin.

  By heating the polyamide resin at a temperature of 330 ° C. or lower and in a non-oxidizing atmosphere, the heat / oxidative deterioration of the polyamide resin can be suppressed, and the heat resistant hue can be improved.

Note that “under a non-oxidizing atmosphere” means an atmosphere in which the content of the non-oxidizing gas is 95% by volume or more. Preferably, it refers to an oxygen-free atmosphere in which the content of the non-oxidizing gas is 100% by volume. It is preferable to carry out in a non-oxidizing atmosphere. Examples of the non-oxidizing atmosphere include an inert gas atmosphere and a reducing gas atmosphere. Here, the inert gas is not particularly limited, but helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), nitrogen (N ₂ ), and the like can be used. The said inert gas may be used independently or may be used with the form of 2 or more types of mixed gas. Further, a reducing gas may be mixed in the inert gas. The reducing gas is not particularly limited, but hydrogen (H ₂ ) gas and carbon monoxide (CO) gas are preferable. Among these, from the viewpoint of safety, it is preferable to use an inert gas.

  The polyamide resin molded body preferably has a yellowness (yellow index value: YI) of 20 or less after heating at 170 ° C. for 8 hours in an air atmosphere. Thus, even if it uses a polyamide molded object under the environment exposed to high temperature for a long time, such as a LED reflector, by using the polyamide molded object whose yellowness after a severe heating test is 20 or less and low yellowness, A stable hue is maintained. More preferably, the yellowness (YI) after heating the molded body at 170 ° C. for 8 hours is 16 or less. The yellowness measurement method employs a value measured by the method described in the column of Example (5) Hue described later.

[Production method of polyamide molded body]
A preferable method for producing a polyamide molded body of the present invention satisfies the following (1) and (2) by polycondensation of a dicarboxylic acid compound containing terephthalic acid and a diamine compound containing an aliphatic diamine having 12 carbon atoms. A process for producing a polyamide molded body comprising: a step of obtaining a polyamide resin; and a step of heating and melting the polyamide resin in a non-oxidizing atmosphere at a temperature of 330 ° C. or lower; (1) a melting point of 265 to 300 ° C. Yes, (2) The molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is aliphatic diamine having 10 carbon atoms: aliphatic diamine having 12 carbon atoms = 0 : 100-70: 30.

1. Step of obtaining a polyamide resin The polycondensation method of a dicarboxylic acid compound and a diamine compound is not particularly limited and may be appropriately selected from conventionally known arbitrary methods. For example, an aqueous solution of a dicarboxylic acid compound and a diamine compound is prepared. A heating polymerization method in which a dehydration reaction proceeds by heating at high temperature and high pressure, or a method in which a low-order condensate is obtained by pressure-heating polymerization of a dicarboxylic acid compound and a diamine compound, and then the low-order condensate is increased in molecular weight Etc. Among them, a method in which a dicarboxylic acid compound and a diamine compound are heated and polymerized under pressure to obtain a low-order condensate, and then the low-order condensate is increased in molecular weight is preferable.

  Specifically, a step of producing a low-order condensate by performing a polycondensation reaction between the dicarboxylic acid compound and the diamine compound, a step of discharging and cooling the low-order condensate, and the cooled low-order condensate And a solid-phase polymerization step. According to such a production method, it is possible to obtain a polyamide resin excellent in heat-resistant hue without causing almost any production problems such as generation of gel during production.

  Hereinafter, although such a manufacturing method is demonstrated in detail for every process, this invention is not restrict | limited at all to this.

<Process for producing low-order condensate>
In this step, a polycondensation reaction between the dicarboxylic acid compound and the diamine compound is performed to produce a low-order condensate of polyamide resin.

  The low-order condensate is synthesized by, for example, charging an aqueous solution of the above-mentioned monomer or salt into a commonly used pressure polymerization tank and performing a polycondensation reaction in an aqueous solvent under stirring conditions.

  The aqueous solvent is a solvent mainly composed of water. The solvent used other than water is not particularly limited as long as it does not affect the polycondensation reactivity and solubility. For example, alcohols such as methanol, ethanol, propanol, butanol, and ethylene glycol are used. Is mentioned.

  The amount of water in the reaction system when starting the polycondensation reaction is preferably such that the amount of water in the reaction system at the end of the reaction is 15 to 35% by weight. Specifically, the amount of water in the reaction system when starting the polycondensation reaction is preferably 17 to 60% by weight. If the amount of water in the reaction system at the start of the polycondensation reaction is within this range, an almost uniform solution is formed at the start of the polycondensation reaction, which is excessive to distill off the water in the polycondensation step. There is no risk of requiring time and energy, and thermal degradation of the low-order condensate due to extension of the reaction time can be reduced.

  In this step, a phosphorus catalyst can be used from the viewpoints of improving the polycondensation rate and preventing deterioration during the polycondensation reaction. Phosphorous catalysts include hypophosphites, phosphites, phosphates, hypophosphorous acid, phosphorous acid, phosphoric acid, phosphate esters, polymetaphosphoric acids, polyphosphoric acids, phosphine oxides, or phosphonium halogens The compound is preferred, and at least one selected from the group consisting of hypophosphite, phosphite, phosphate, hypophosphorous acid, phosphorous acid, and phosphoric acid is more preferred, and hypophosphite More preferred is at least one selected from the group consisting of phosphonate, hypophosphorous acid, and phosphoric acid. Specific examples of these phosphorus-based catalysts are the same as the specific examples of the above-described phosphorus compounds, and thus description thereof is omitted here.

  As addition amount of a phosphorus catalyst (phosphorus compound), 0.1-1.0 weight part is preferable with respect to 100 weight part of total monomers, and 0.2-0.5 weight part is more preferable. The catalyst may be added at any time as long as the solid phase polymerization is completed, but it is preferable that the catalyst is added from the raw material charging to the completion of polycondensation of the low-order condensate. Moreover, you may add many times. Further, two or more different phosphorus catalysts may be added in combination.

  Moreover, this process can perform above-described polycondensation reaction in presence of terminal blocker. Use of the end-capping agent makes it easier to adjust the molecular weight of the low-order condensate and finally produced polyamide resin, and further improves the melt stability of the low-order condensate and finally produced polyamide resin. The end capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the terminal amino group or terminal carboxyl group in the low-order condensate. For example, acid such as monocarboxylic acid, monoamine, phthalic anhydride, etc. Anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols and the like can be mentioned. The terminal blocking agents can be used alone or in combination of two or more.

  Among these, monocarboxylic acids or monoamines are preferably used as end capping agents from the viewpoints of reactivity and stability of the capping ends, and in addition to the above properties, monocarboxylic acids are easy to handle. Is more preferably used.

  The monocarboxylic acid preferably used as the end-capping agent is not particularly limited as long as it is a monocarboxylic acid having reactivity with an amino group. For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, capryl Aliphatic monocarboxylic acids such as acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α- Mention may be made of aromatic monocarboxylic acids such as naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, phenylacetic acid, or any mixture thereof. Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, in terms of reactivity, stability of the sealing end, price, etc. Benzoic acid is more preferred.

  The monoamine preferably used as the end-capping agent is not particularly limited as long as it is a monoamine having reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, Aliphatic monoamines such as stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine; alicyclic monoamines such as cyclohexylamine, dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, naphthylamine, or any of these Mention may be made of mixtures. Among these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are particularly preferable from the viewpoints of reactivity, boiling point, stability of the capped end and price.

  The amount of the end-capping agent used in the production of the low-order condensate may vary depending on the reactivity, boiling point, reaction apparatus, reaction conditions, etc. of the end-capping agent used, but is usually the sum of the dicarboxylic acid compound and the diamine compound. It is preferable to use within a range of 0.01 to 15 mol% with respect to 100 mol%.

  The synthesis of the low-order condensate of the present invention is usually carried out by raising the temperature and raising the pressure under stirring conditions. The polymerization temperature is controlled after the raw materials are charged. The polymerization pressure is controlled in accordance with the progress of the polymerization.

  The reaction temperature in this step is preferably 230 to 260 ° C. If it is this range, side reactions, such as gelatinization, do not occur easily and the target low-order condensate can be obtained efficiently. The reaction temperature is more preferably 240 to 250 ° C.

  The reaction pressure in this step is preferably 0.5 to 5 MPa. If the reaction pressure is within this range, the temperature in the reaction system and the amount of water in the reaction system can be easily controlled, and the low-order condensate can be easily discharged. Moreover, since a reactor with low pressure resistance can be used, it is economically advantageous, and the degree of polymerization of the low-order condensate can be increased by shifting the amount of water in the reaction system low. The reaction pressure is more preferably 1.0 to 4.5 MPa.

  Moreover, it is preferable that the reaction time in this process is 0.5 to 4 hours. The reaction time here refers to the time required from the arrival of the reaction temperature of the present invention to the start of the discharge operation. When the reaction time is within this range, a sufficient reaction rate is reached, and unreacted substances hardly remain, and a low-order condensate with uniform properties can be obtained. Moreover, a high-quality low-order condensate can be obtained without giving an excessive heat history. The reaction time is more preferably 1 to 3 hours.

  The water content in the reaction system at the end of the reaction of the low-order condensate in this step is preferably 15 to 35% by weight. The term “at the end of the reaction” as used herein means a time point at which a low-order condensate having a predetermined degree of polymerization is reached and a discharge operation is started, and the amount of condensed water generated during the reaction is also combined. In order to make the amount of water within the scope of the present invention, a predetermined amount of water is distilled off when adjusting the reaction pressure in a device equipped with a condenser and a pressure regulating valve in order to make the amount of water charged taking into account the amount of generated condensed water. Can be adjusted. If the water content is within this range, the low-order condensate is hardly precipitated or solidified in the reaction system, and the discharge of the low-order condensate is facilitated. In addition, it is easy to obtain a low-order condensate having a sufficient degree of polymerization, and since the amount of water to be evaporated and separated at the time of discharge is small, the discharge rate can be increased and the production efficiency can be improved. The amount of water in the reaction system at the end of the reaction is more preferably 20 to 35% by weight.

  Further, before the polymerization of the low-order condensate, a salt preparation step and / or a concentration step can be added as necessary. The salt tone is a step of producing a salt from a dicarboxylic acid component and a diamine component, and in the range of pH ± 0.5 of the neutralization point of the salt, and further, pH ± 0.3 of the neutralization point of the salt. It is preferable to adjust to the range. In the concentration, the raw material charge concentration value is preferably +2 to + 90% by weight, and more preferably concentrated to a concentration of +5 to + 80% by weight. The temperature in the concentration step is preferably in the range of 90 to 220 ° C, more preferably 100 to 210 ° C, and particularly preferably 130 to 200 ° C. The pressure in the concentration step is preferably 0.1 to 2.0 MPa. Usually, the concentration pressure is controlled below the polymerization pressure. Further, for the purpose of promoting concentration, for example, a forced discharge operation can be performed by a nitrogen stream or the like. The concentration step is effective for shortening the polymerization time.

  In this step, the logarithmic viscosity (hereinafter also simply referred to as IV) measured at a temperature of 25 ° C. at a concentration of 0.5 g / dL in concentrated sulfuric acid of the low-order condensate after being taken out of the reaction vessel (after cooling). The reaction is preferably carried out at 0.07 to 0.40 dL / g. If IV is in this range, the fusion of resin powders during solid phase polymerization due to the presence of a low-melting substance and adhesion to the apparatus can be suppressed, and the reaction during the production of low-order condensates can be suppressed. Precipitation and solidification in the system can be suppressed. The IV is more preferably 0.10 to 0.25 dL / g.

  In this step, the polycondensation reaction for obtaining a low-order condensate may be performed in a batch manner or a continuous manner. Moreover, it is preferable to perform the polycondensation reaction for producing | generating a low-order condensate under stirring from points, such as adhesion prevention of the low-order condensate to a reaction container, and a uniform progression of a polycondensation reaction.

<Process for discharging and cooling low-order condensate>
Next, the low-order condensate produced above is taken out from the reaction vessel. When taking out the low-order condensate from the reaction vessel, the temperature of the reaction system is in the range of 230 to 260 ° C., and the water content in the reaction system at the end of the reaction is in the range of 15 to 35% by weight. Sometimes it is preferred to remove the low-order condensate from the reaction vessel in an inert gas atmosphere at a pressure below atmospheric pressure. According to such a discharge method, it is not necessary to use a pressure vessel for removal adjusted to a predetermined pressure, and it is also necessary to take out the low-order condensate from the reaction vessel while separately supplying water vapor into the reaction vessel. Without obtaining a low-order condensate in a non-foamed granular form (powder or granular form) that has low thermal degradation, sufficiently high logarithmic viscosity, and high bulk specific gravity. be able to.

  The inert gas atmosphere preferably has an oxygen concentration of 1% by volume or less from the viewpoint of preventing oxidative degradation of the low-order condensate.

The discharge rate of the low-order condensate from the reaction vessel can be appropriately adjusted according to the scale of the reaction vessel, the amount of contents in the reaction vessel, the temperature, the size of the take-out port, the length of the take-out nozzle portion, and the like. However, in general, it is preferable that the discharge speed per discharge port cross-sectional area be within a range of 2000 to 20000 kg / s / m ² . Within this range, in the solid phase polymerization process described later, collapse, aggregation, fusion to the reactor wall, etc. are unlikely to occur, the handleability is excellent, and the polymerization apparatus can be filled in a large amount. The volumetric efficiency of the apparatus used in the polymerization process can be improved.

  The low-order condensate taken out from the reaction vessel is instantaneously reduced to preferably 100 ° C. or less due to the latent heat of vaporization of the water at the time of taking-out, so that thermal degradation and deterioration due to oxygen hardly occur.

  In addition, the discharged low-order condensate evaporates most of the accompanying water due to the sensible heat of the low-order condensate, so the cooling of the low-order condensate and the drying process are performed simultaneously in this step. is there. It is preferable to perform the discharge treatment under the flow of an inert gas such as nitrogen or under reduced pressure from atmospheric pressure in order to increase the efficiency of drying and cooling. In addition, by installing a cyclone-type solid-gas separation device as a discharge container, not only can the powder be prevented from scattering outside the system, but also the discharge process can be performed at a high gas linear velocity, so drying and cooling efficiency can be improved. This is preferable because it can be increased.

  The low-order condensate thus obtained has a sufficiently high logarithmic viscosity as described above, and the residual amount of unreacted material is also low. The solid-phase polymerization can be carried out at a high temperature without causing fusion or aggregation of the resin, and there is little deterioration due to side reactions.

  Moreover, in this process, you may further perform the compacting process and granulation process for aligning a particle size as needed.

<Solid-state polymerization>
In this step, the low-order condensate taken out from the reaction vessel in the above is subjected to a high degree of polymerization by solid phase polymerization to produce a polyamide resin. The solid phase reaction may be carried out as it is after taking out the low-order condensate from the reaction vessel, or after drying the low-order condensate taken out from the reaction vessel, or the low-order condensate taken out from the reaction vessel. May be carried out after storage, or after the above-described compacting treatment or granulation treatment is performed on the low-order condensate taken out from the reaction vessel. When the degree of polymerization is increased by solid phase polymerization, a polyamide resin with less heat deterioration can be obtained.

  The polymerization method and conditions for solid-phase polymerization of the low-order condensate are not particularly limited, and a method capable of increasing the degree of polymerization while maintaining a solid state without causing fusion, aggregation, or deterioration of the low-order condensate and Any condition is acceptable.

  However, in order to prevent oxidative degradation of the low-order condensate and the resulting polyamide resin, it is preferable to perform solid-state polymerization in an inert gas atmosphere such as helium gas, argon gas, nitrogen gas, carbon dioxide gas, or under reduced pressure. .

  The reaction temperature in the solid phase polymerization is not particularly limited, but is preferably 200 to 250 ° C, more preferably 210 to 240 ° C.

  There is no particular limitation on the solid-phase polymerization apparatus used in this step, and any known apparatus can be used. Specific examples of the solid phase polymerization apparatus include, for example, a uniaxial disk type, a kneader, a biaxial paddle type, a vertical tower type apparatus, a vertical tower type apparatus, a rotary drum type, or a double cone type solid phase polymerization. Examples thereof include an apparatus and a drying device.

  The reaction time of solid phase polymerization is not particularly limited, but usually 1 to 20 hours is preferably employed. During the solid state polymerization reaction, the low-order condensate may be stirred mechanically or by a gas stream.

  In the present invention, the above-mentioned various additives may be added, if necessary, at any step after the step of producing the low-order condensate, the step of solid-phase polymerization, or the solid-phase polymerization. The mixing method of the additive is not particularly limited. For example, a method of mixing with a Hensell mixer, a V blender, a ribbon blender, a tumbler blender, or the like, or a single screw extruder, a multi-screw extruder, a kneader, After melt-kneading with a Banbury mixer etc., it can manufacture by the method of assembling or grind | pulverizing.

  According to the manufacturing method as described above, a polyamide resin excellent in heat-resistant hue can be obtained with almost no manufacturing problems such as gelation.

2. The step of molding the polyamide resin The method of molding the polyamide resin is not particularly limited, but the polyamide resin of the present invention does not require heating at a temperature exceeding 330 ° C., and the heat resistant hue due to thermal deterioration can be reduced. It can be suitably used for molding methods that require (melting). Examples of such a molding method include injection molding, blow molding, extrusion molding, and compression molding. Among them, it is preferable to use an injection molding method, that is, the polyamide resin molded body is an injection molded body. In the injection molding method, a mold corresponding to the shape of the resin molded product can be used, and a resin molded product having a complicated shape can be manufactured.

  As described above, the injection molding is suitable in the present invention, but the injection molding is performed using an injection molding machine, and suitable molding conditions are appropriately set according to the resin composition to be used and the product shape. The molding conditions include cylinder temperature, mold temperature, injection pressure, holding pressure, screw rotation speed, cushion amount, injection speed, injection time, pressure holding time, cooling time, and the like.

  In the present invention, the cylinder temperature of the molding machine may be set so that the actually measured temperature of the polyamide resin is 330 ° C. or less. At this time, the cylinder temperature of the molding machine is preferably set to 330 ° C. or lower, more preferably 320 ° C. or lower, so that the actually measured temperature of the polyamide resin is 330 ° C. or lower. The cylinder set temperature here refers to the highest set temperature when different temperatures are set in each part of the cylinder.

  The cylinder temperature of the molding machine is preferably set to 5 ° C. or higher from the melting point of the polyamide resin so that the actually measured temperature of the polyamide resin is higher than the melting point. By molding at such a temperature, the polyamide resin is sufficiently melted and the dispersibility in the resin composition is improved.

  In addition, the non-oxidizing atmosphere can be changed to a non-oxidizing atmosphere by flowing a non-oxidizing gas into the cylinder.

  The injection speed when using the injection molding method is preferably 1 mm / second or more and 60 mm / second or less, and more preferably 5 mm / second or more and 50 mm / second or less. By setting the injection speed within such a range, a resin molded product having an excellent surface appearance can be obtained. Moreover, although mold temperature is not specifically limited, It is preferable that it is 50-200 degreeC, and it is more preferable that it is 100-180 degreeC.

  The polyamide resin molded body obtained by the above production method can be used for electric / electronic parts, automobile parts, reflective materials and the like. In particular, the polyamide resin molded body of the present invention is preferably used for a reflector because it can suppress discoloration even when used under high temperature conditions for a long time. As a specific example, it can be used as a reflector for light emitting devices such as various electric and electronic components, indoor lighting, ceiling lighting, outdoor lighting, automobile lighting, display equipment, and headlights. Among them, since the LED is often in a high temperature environment around 100 ° C. due to high brightness and high output, if the polyamide molded body of the present invention with improved heat-resistant hue is used as the LED reflector, sufficient brightness is obtained. Can be maintained. Therefore, a preferred embodiment of the present invention is a polyamide molded body that is an LED reflector.

  The LED reflector molded by the polyamide resin is sealed, bonded, adhered, and the like by the LED element and the sealing resin.

  The present invention will be described in further detail using the following examples and comparative examples. However, the technical scope of the present invention is not limited only to the following examples. The evaluation of logarithmic viscosity (IV), terminal amino group concentration, melting point, hue, and discoloration resistance test were conducted by the following methods.

(1) Logarithmic viscosity A sample solution was prepared by dissolving a sample in 96% concentrated sulfuric acid at a concentration of 0.5 g / dL. The falling seconds of 96% concentrated sulfuric acid and the sample solution were measured using a Ubbelohde viscosity tube at a temperature of 25 ° C., and calculated according to the following formula.

(2) Terminal amino group concentration ([NH ₂ ])
0.3 to 0.5 g of the sample was precisely weighed, 20 mL of orthocresol was added, and the mixture was dissolved by heating to about 170 ° C. with stirring in a nitrogen atmosphere. After complete dissolution, the mixture was cooled, and 15 mL of benzyl alcohol was added, followed by stirring for 5 minutes. The solution thus prepared was subjected to neutralization titration with a 0.1N hydrochloric acid aqueous solution, and the end point was determined by potentiometric measurement.

(3) Phosphorus compound concentration measurement in resin Measuring device: ICP-AES 720-ES manufactured by Agilent Technologies
Sample pretreatment: Sulfuric acid was added to a sample weighed in a crucible, heated and incinerated.

  The ash was dissolved in potassium hydrogen sulfate and then dissolved in dilute nitric acid, and the volume was adjusted with pure water. For quantitative analysis, a calibration curve was previously prepared with a phosphorus compound solution having a known concentration.

(4) Melting point Using a DSC manufactured by Seiko Instruments Inc., a non-crystallized sample was heated from 30 ° C. to 350 ° C. at a temperature rising rate of 10 ° C./min under a nitrogen flow at a flow rate of 10 ml / min for 5 min. The glass transition temperature was measured at a holding and temperature decrease rate of 10 ° C./min up to 100 ° C., and the endothermic peak temperature due to melting at the time of temperature increase was measured as the melting point.

(5) Hue The hue was measured using a small color whiteness meter NW-11 manufactured by Nippon Denshoku Industries Co., Ltd.

Illumination / light reception conditions: 45 ° annular illumination, 0 ° light reception Measurement method: diffraction grating, post-spectral method Measurement area: 10 mmφ, light source: Pulse Xenon lamp
Measurement light source, observation conditions: D65 / 2 °
Measurement item: Yellowness YI
(6) Discoloration resistance test (heat resistant hue)
The molded body was heat-treated at 170 ° C. for 8 hours in an air atmosphere in a heating oven, and the hue before and after the treatment was measured to evaluate discoloration resistance (heat-resistant hue).

(Production Example 1)
As raw materials, 179.72 g (1.082 mol) of terephthalic acid, 219.60 g of 1,12-diaminododecane (100 mol% in the diamine compound), 3.96 g (0.032 mol) of benzoic acid, sodium hypophosphite Monohydrate (SHM) 0.403 g (3.80 mmol, 0.1 part by weight with respect to 100 parts by weight of the total amount of terephthalic acid, 1,12-diaminododecane, and benzoic acid), and 269 g of water (feed material) Was charged into an autoclave reaction vessel having an internal volume of 1 liter equipped with a pressure reducer, a pressure regulating valve, and a bottom discharge valve, and nitrogen substitution was performed. While stirring, the temperature was raised to 180 ° C. over 1 hour and held for 0.5 hour. Thereafter, the internal temperature was raised to 250 ° C. and held over 1 hour. After the internal pressure of the reaction tank reached 3.5 MPa, the reaction was continued for 2.5 hours while distilling off water so as to maintain the same pressure.

  After the predetermined reaction time has elapsed, while maintaining the temperature of the reaction vessel and the amount of water in the reaction system (30% by weight), the produced low-order condensate is passed through the bottom discharge valve at room temperature (25 ° C.) under nitrogen flow. And discharged to a receiver under atmospheric pressure conditions to obtain a white, powdery low-order condensate.

  300 g of the obtained low-order condensate was charged into a 1000 mL round bottom flask, placed in a rotary evaporator with an oil bath, and after nitrogen substitution, immersed in an oil bath while rotating the flask under a nitrogen flow of 1 L / min, After raising the internal temperature to 230 ° C. over 1 hour, the solid state polymerization reaction was continued at the same temperature for 5 hours. After a predetermined reaction time, the mixture was cooled to room temperature (25 ° C.) to obtain a highly polymerized polyamide resin.

(Production Example 2)
The amount of raw materials charged was 179.72 g (1.082 mol) of terephthalic acid, 219.60 g of 1,12-diaminododecane (100 mol% in the diamine compound), 3.96 g (0.032 mol) of benzoic acid, hypochlorous acid, Sodium phosphate monohydrate (SHM) 0.807 g (7.61 mmol, terephthalic acid, 1,10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.2 parts per 100 parts by weight Parts by weight) and 269 g of water (40% by weight with respect to the charged raw materials). A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 3)
The amount of raw materials charged was 179.72 g (1.082 mol) of terephthalic acid, 219.60 g of 1,12-diaminododecane (100 mol% in the diamine compound), 3.96 g (0.032 mol) of benzoic acid, hypochlorous acid, Sodium phosphate monohydrate (SHM) 1.210 g (11.41 mmol, terephthalic acid, 1,10-diaminodecane, 1,12-diaminododecane, and benzoic acid 0.3 parts per 100 parts by weight) Parts by weight) and 270 g of water (40% by weight with respect to the charged raw materials), a polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 4)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 219.60 g of 1,12-diaminododecane (100 mol% in the diamine compound), 3.96 g (0.032 mol) of benzoic acid, hypochlorous acid, 1.613 g (15.22 mmol, sodium terephthalic acid, 1,10-diaminodecane, 1,12-diaminododecane, and benzoic acid in a total amount of 100 parts by weight of sodium phosphate monohydrate (SHM) Parts by weight) and 270 g of water (40% by weight with respect to the charged raw materials), a polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 5)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 197.64 g of 1,12-diaminododecane (0.988 mol = 90 mol% in the diamine compound), and 18.92 g of 1,10-diaminodecane. (0.110 mol = 10 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.400 g (3.78 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 267 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 6)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 175.68 g of 1,12-diaminododecane (0.878 mol = 80 mol% in the diamine compound), 37.85 g of 1,10-diaminodecane. (0.220 mol = 20 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.397 g (3.75 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 265 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 7)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 175.68 g of 1,12-diaminododecane (0.878 mol = 80 mol% in the diamine compound), 37.85 g of 1,10-diaminodecane. (0.220 mol = 20 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 1.589 g (14.99 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.4 parts by weight based on 100 parts by weight), and 266 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 8)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 153.72 g of 1,12-diaminododecane (0.769 mol = 70 mol% in the diamine compound), 56.77 g of 1,10-diaminodecane. (0.329 mol = 30 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.394 g (3.72 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 263 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 9)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 153.72 g of 1,12-diaminododecane (0.769 mol = 70 mol% in the diamine compound), 56.77 g of 1,10-diaminodecane. (0.329 mol = 30 mol% in diamine compound), 3.96 g (0.032 mol) of benzoic acid, 1.577 g (14.87 mmol, terephthalic acid, 1) sodium hypophosphite monohydrate (SHM) , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid in a total amount of 0.4 parts by weight based on 100 parts by weight), and 264 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 10)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 131.76 g of 1,12-diaminododecane (0.659 mol = 60 mol% in the diamine compound), 75.70 g of 1,10-diaminodecane. (0.439 mol = 40 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.391 g (3.69 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 261 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 11)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 131.76 g of 1,12-diaminododecane (0.659 mol = 60 mol% in the diamine compound), 75.70 g of 1,10-diaminodecane. (0.439 mol = 40 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.782 g (7.38 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid in a total amount of 0.2 parts by weight based on 100 parts by weight), and 261 g of water (40% by weight based on the charged raw materials). A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 12)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 109.80 g of 1,12-diaminododecane (0.549 mol = 50 mol% in the diamine compound), 94.62 g of 1,10-diaminodecane. (0.549 mol = 50 mol% in the diamine compound), 3.96 g (0.032 mol) of benzoic acid, 0.388 g (3.66 mmol, terephthalic acid, 1) sodium hypophosphite monohydrate (SHM) , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 259 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 13)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 109.80 g of 1,12-diaminododecane (0.549 mol = 50 mol% in the diamine compound), 94.62 g of 1,10-diaminodecane. (0.549 mol = 50 mol% in diamine compound), 3.96 g (0.032 mol) of benzoic acid, 1.552 g (14.65 mmol, terephthalic acid, 1) sodium hypophosphite monohydrate (SHM) , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.4 parts by weight based on the total amount of 100 parts by weight), and 260 g of water (40% by weight based on the charged raw materials). A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 14)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 65.88 g of 1,12-diaminododecane (0.329 mol = 30 mol% in the diamine compound), 132.47 g of 1,10-diaminodecane. (0.769 mol = 70 mol% in diamine compound), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.382 g (3.60 mmol, terephthalic acid, 1 , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid, 0.1 parts by weight based on 100 parts by weight), and 255 g of water (40% by weight with respect to the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 15)
The amount of raw materials charged was 179.72 g (1.082 mol) of terephthalic acid, 170.28 g (0.988 mol = 90 mol%) of 1,10-diaminodecane, and 22.00 g (0.002 mol) of 1,12-diaminododecane. 110 mol = 10 mol%), benzoic acid 3.96 g (0.032 mol), sodium hypophosphite monohydrate (SHM) 0.376 g (3.55 mmol, terephthalic acid, 1,10-diaminodecane, The same as Production Example 1 except that the total amount of 1,12-diaminododecane and benzoic acid was 0.1 parts by weight with respect to 100 parts by weight) and 251 g of water (40% by weight with respect to the charged raw materials). Thus, a polyamide resin was obtained.

(Production Example 16)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 21.96 g of 1,12-diaminododecane (0.110 mol = 90 mol% in the diamine compound), 170.31 g of 1,10-diaminodecane. (0.988 mol = 10 mol% in diamine compound), 3.96 g (0.032 mol) of benzoic acid, 1.504 g (14.19 mmol, terephthalic acid, 1) sodium hypophosphite monohydrate (SHM) , 10-diaminodecane, 1,12-diaminododecane, and benzoic acid in a total amount of 0.4 parts by weight based on 100 parts by weight) and 252 g of water (40% by weight based on the charged raw materials) A polyamide resin was obtained in the same manner as in Production Example 1.

(Production Example 17)
The amount of raw materials charged was 179.2 g (1.082 mol) of terephthalic acid, 189.24 g of 1,10-diaminodecane (1.098 mol = 100 mol% in the diamine compound), 3.96 g of benzoic acid (0.032 Mol), 0.373 g (3.52 mmol, sodium phosphite monohydrate (SHM), 0.1 part by weight based on 100 parts by weight of the total amount of terephthalic acid, 1,10-diaminodecane, and benzoic acid) ) And 249 g of water (40% by weight based on the charged raw materials), to obtain a polyamide resin by the same method as in Production Example 1.

Table 1 below shows the melting point, phosphorus compound concentration, terminal amino group concentration [NH ₂ ], and phosphorus compound concentration / terminal amino group concentration by IV, DSC measurement of the obtained polyamide resin.

Example 1
The polyamide resin obtained in Production Example 1 was molded under the following conditions to obtain a polyamide molded body.

  Using a SE18DUZ, which is an injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., strip-shaped test pieces (size 80 mm × 10 mm × 4.0 mm) were produced under the conditions shown below.

Cylinder atmosphere: N ₂
Resin temperature in the cylinder: 310 ° C (Cylinder temperature: 310 ° C)
Mold temperature: 150 ° C
Injection pressure: 120-140 MPa
Injection speed: 30 mm / sec Screw rotation speed: 150 rpm
Cooling time: 45 seconds (Comparative Example 1)
A polyamide molded body was obtained in the same manner as in Example 1 except that the cylinder atmosphere was changed to the atmosphere.

(Comparative Example 2)
Similar to Example 1, except that the polyamide resin obtained in Production Example 15 was used instead of the polyamide resin obtained in Production Example 1, and the resin temperature in the cylinder was changed to 330 ° C. (cylinder temperature: 330 ° C.). Thus, a polyamide molded body was obtained.

(Comparative Example 3)
A polyamide molded body was obtained in the same manner as in Comparative Example 2 except that the cylinder atmosphere was changed to air.

(Comparative Example 4)
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 17 was used instead of the polyamide resin obtained in Production Example 1 and the resin temperature in the cylinder was 340 ° C. It was.

(Comparative Example 5)
A polyamide molded body was obtained in the same manner as in Comparative Example 4 except that the cylinder atmosphere was under the atmosphere.

(Example 2)
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 2 was used instead of the polyamide resin obtained in Production Example 1.

(Example 3)
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 3 was used instead of the polyamide resin obtained in Production Example 1.

Example 4
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 4 was used instead of the polyamide resin obtained in Production Example 1.

(Comparative Example 6)
A polyamide molded body was obtained in the same manner as in Comparative Example 2 except that the polyamide resin obtained in Production Example 16 was used instead of the polyamide resin obtained in Production Example 15.

(Comparative Example 7)
A polyamide molded body was obtained in the same manner as in Example 1 except that the resin temperature in the cylinder was 340 ° C.

(Example 5)
Similar to Example 1 except that the polyamide resin obtained in Production Example 5 was used instead of the polyamide resin obtained in Production Example 1, and the resin temperature in the cylinder was 325 ° C. (cylinder temperature: 325 ° C.). Thus, a polyamide molded body was obtained.

(Example 6)
Similar to Example 1 except that the polyamide resin obtained in Production Example 6 was used instead of the polyamide resin obtained in Production Example 1, and the resin temperature in the cylinder was 325 ° C. (cylinder temperature: 325 ° C.). Thus, a polyamide molded body was obtained.

(Example 7)
A polyamide molded body was obtained in the same manner as in Example 6 except that the resin temperature in the cylinder was 290 ° C. (cylinder temperature: 290 ° C.).

(Example 8)
A polyamide molded body was obtained in the same manner as in Example 7 except that the polyamide resin obtained in Production Example 7 was used instead of the polyamide resin obtained in Production Example 6.

Example 9
Similar to Example 1 except that the polyamide resin obtained in Production Example 8 was used instead of the polyamide resin obtained in Production Example 1, and the resin temperature in the cylinder was 325 ° C. (cylinder temperature: 325 ° C.). Thus, a polyamide molded body was obtained.

(Example 10)
A polyamide molded body was obtained in the same manner as in Example 9, except that the polyamide resin obtained in Production Example 9 was used instead of the polyamide resin obtained in Production Example 8.

(Example 11)
Similar to Example 1 except that the polyamide resin obtained in Production Example 12 was used instead of the polyamide resin obtained in Production Example 1, and the resin temperature in the cylinder was 280 ° C. (cylinder temperature: 280 ° C.). Thus, a polyamide molded body was obtained.

(Example 12)
A polyamide molded body was obtained in the same manner as in Example 11 except that the polyamide resin obtained in Production Example 13 was used instead of the polyamide resin obtained in Production Example 12.

(Example 13)
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 14 was used and the resin temperature in the cylinder was 300 ° C. (cylinder temperature: 300 ° C.).

(Example 14)
A polyamide molded body was obtained in the same manner as in Example 1 except that the polyamide resin obtained in Production Example 10 was used and the resin temperature in the cylinder was 280 ° C. (cylinder temperature: 280 ° C.).

(Example 15)
A polyamide molded body was obtained in the same manner as in Example 14 except that the polyamide resin obtained in Production Example 11 was used instead of the polyamide resin obtained in Production Example 10.

  With respect to each molded body obtained in Examples 1 to 15 and Comparative Examples 1 to 7, yellowness YI of the molded body after the initial stage and after the discoloration resistance test was measured. The results are shown in Table 2 below.

  As is clear from Table 2 above, it was found that the polyamide resins of the present invention obtained in Examples 1 to 15 had a hue after heat resistance test of 20 or less and were excellent in heat resistant hue. On the other hand, it was found that the polyamide resins outside the scope of the present invention obtained in Comparative Examples 1 to 7 were inferior in heat resistant hue.

Claims (6)

A polyamide molded body obtained by heating and molding a polyamide resin at a temperature of 330 ° C. or lower and in a non-oxidizing atmosphere,
The polyamide resin is a polyamide resin obtained by a polycondensation reaction between a dicarboxylic acid compound and a diamine compound and satisfying the following (1) and (2):
A polyamide molded body in which the dicarboxylic acid compound includes terephthalic acid, and the diamine compound includes an aliphatic diamine having 12 carbon atoms;
(1) The melting point is 265 to 300 ° C.
(2) The molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is: aliphatic diamine having 10 carbon atoms: aliphatic diamine having 12 carbon atoms = 0: 100 ~ 70: 30.   The ratio (phosphorus compound concentration / terminal amino group concentration) of the phosphorus compound concentration (unit: μmol / g) contained in the polyamide resin to the terminal amino group concentration (unit: μmol / g) of the polyamide resin is 0.2. The polyamide molded product according to claim 1, which is -1.0.   The polyamide molded product according to claim 2, wherein the phosphorus compound concentration / terminal amino group concentration is 0.5 to 1.0.   The polyamide molded body according to any one of claims 1 to 3, wherein the melting point is 265 ° C or higher and lower than 280 ° C.   The polyamide molded body according to any one of claims 1 to 4, wherein the yellowness (YI) after heating at 170 ° C for 8 hours in an air atmosphere is 20 or less. A step of obtaining a polyamide resin satisfying the following (1) and (2) by polycondensation of a dicarboxylic acid compound containing terephthalic acid and a diamine compound containing an aliphatic diamine having 12 carbon atoms;
A step of heating and molding the polyamide resin in a non-oxidizing atmosphere at a temperature of 330 ° C. or less;
A method for producing a polyamide molded body comprising:
(1) The melting point is 265 to 300 ° C.
(2) The molar ratio of the aliphatic diamine having 10 carbon atoms and the aliphatic diamine having 12 carbon atoms in the diamine compound is: aliphatic diamine having 10 carbon atoms: aliphatic diamine having 12 carbon atoms = 0: 100 ~ 70: 30.