JP2004211083A - High molecular weight polyamide resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high molecular weight polyamide resin composition suitable as industrial materials such as various mechanical indusrial parts and electric/electronic parts, which has the superior moldability in that stability of the melt viscosity at the time of molding is excellent and fouling of the mold caused by thermal decomposition components is reduced and which gives a molded product excellent in sliding property, abrasion resistance and appearance. <P>SOLUTION: The polyamide resin composition comprises, based on 100 pts.wt. of a high molecular weight polyamide 66 (A) having a relative viscosity (RV) of 80-350, 0.005-0.1 pt.wt. of an organic thermal stabilizer (B) chosen from hindered phenols, 0.005-0.1 pt.wt. of a higher fatty acid ester (C) having an acid number of 5-50 (mgKOH/g) and a saponification number of 50-200 (mgKOH/g), and 0.01-0.1 pt.wt. of a metal salt of a higher fatty acid (D). <P>COPYRIGHT: (C)2004,JPO&amp;NCIPI

Description

  The present invention provides an excellent moldability that is excellent in stability of melt viscosity during molding and suitable for industrial materials such as various mechanical industrial parts and electric and electronic parts, and that reduces contamination of a mold by a thermal decomposition component. The present invention relates to a high-molecular-weight polyamide resin composition having excellent slidability, abrasion resistance, and appearance of a molded article obtained.

  Polyamide resins have excellent mechanical properties, heat resistance, chemical resistance and the like, and are therefore used as engineering plastics in various applications such as automotive parts, electronic and electrical parts, and industrial parts. In recent years, the shape, thickness, and specialization of the shape of a polyamide resin molded product have been complicated, and a polyamide resin capable of coping with this has been demanded. In addition, high durability polyamide resin material that can be used in harsh environments where excessive external force or heat is applied, and high cycle and recycled pellets can be used from the viewpoint of economical ideas and environmental issues. Polyamide resin materials are also strongly required. For example, application of a high-molecular-weight polyamide resin to structural parts and sliding parts around an automobile engine in a high-temperature atmosphere can be exemplified.

  However, when making such a molded article with a high-molecular-weight polyamide resin, the molding temperature is increased to obtain melt fluidity, or the heat residence temperature and time are increased because a hot runner molding method is used. Therefore, there is a problem that the resin is more likely to be thermally oxidized and decomposed or thermally decomposed than those having a molecular weight used in conventional and ordinary injection molding. Such thermal oxidation deterioration discolors the resin and reduces the color tone of the obtained molded article. In addition, the thermal decomposition results in the formation of volatile oligomers, and the volatile components adhere to the surface of the molded article, resulting in impaired appearance of the molded article. Further, since the resin decomposition product adheres to and contaminates the mold and the spinneret, the mold and the spinneret must be frequently cleaned, and the stable molding is continuously inhibited. In addition, as the thermal degradation or thermal decomposition of the resin progresses, the viscosity, that is, the molecular weight of the resin changes. A change in the viscosity of the resin during heat retention not only causes instability of the molding conditions, but also causes a decrease in the mechanical properties of the obtained molded article.

As a method for preventing such thermal degradation and thermal decomposition, a method of performing molding in an inert gas environment is generally mentioned, but it is uneconomical and not practical. In addition, studies have been made to incorporate a heat stabilizer in order to prevent thermal degradation and thermal decomposition of the polyamide. For example, a method of adding phosphoric acid or phosphates, or a metal salt of hypophosphorous acid or phosphorous acid (JP-A-2000-129119), a method of adding a known heat stabilizer (JP-A-7-118926) JP-A-8-3443, JP-A-2001-26647) and the like.
However, although the conventional method exhibits some improvement in thermal stability, it has not yet yielded a satisfactory result.

  INDUSTRIAL APPLICABILITY The present invention has excellent stability of melt viscosity at the time of molding, which is suitable as an industrial material such as various machine industrial parts and electric and electronic parts, reduces the contamination of a mold due to a thermal decomposition component, and has mold release properties and plasticity. An object of the present invention is to provide a heat-resistant high-molecular-weight polyamide resin having excellent moldability and excellent sliding properties, abrasion resistance, and appearance of the obtained molded article.

The present inventors have conducted intensive studies to solve the above-described problems of the present invention, and as a result, a specific high-molecular-weight polyamide, a specific heat stabilizer, a fatty acid ester, a polyamide resin composition containing a specific amount of a fatty acid metal salt, The inventors have found that the above problems can be solved, and have completed the present invention.
That is, the present invention
1. 0.005 to 0.1 parts by weight of an organic heat stabilizer (B) selected from hindered phenols, based on 100 parts by weight of a high molecular weight polyamide 66 (A) having a relative viscosity RV of 80 to 350, 0.005 to 0.1 parts by weight of a higher fatty acid ester (C) having a value of 5 to 50 (mgKOH / g) and a saponification value of 50 to 200 (mgKOH / g), and 0.1 to 0.1 parts by weight of a higher fatty acid metal salt (D). Polyamide resin composition characterized by containing 01 to 0.1 parts by weight,

2. The polyamide resin composition according to the above 1, wherein the component (B), the component (C), and the component (D) are attached to the pellet surface of the component (A).
3. 3. The polyamide resin composition according to the above 1 or 2, wherein the component (A) contains a copper compound (E) and a halogen compound (F) other than halogen copper as a heat stabilizer.
However, (1) the total amount of the component (E) and the component (F) is 0.01 to 1 part by weight with respect to 100 parts by weight of the component (A),
(2) the molar ratio of the halogen element to the copper element is in the range of 1 to 50,

4. The above-mentioned item (1), wherein 0.1 to 100 parts by weight of a heat stabilizer master batch (G) comprising a polyamide resin, a component (E) and a component (F) is added to 100 parts by weight of the component (A). The polyamide resin composition according to any one of to 3,
5. 5. The polyamide resin composition according to the above 4, wherein the component (B), the component (C) and the component (D) are attached to the pellet surface of the component (A) and the component (G).
6). 6. The polyamide resin composition according to the above item 4 or 5, wherein component (G) contains component (E) and component (F) as heat stabilizers.
However, (1) the total amount of the component (E) and the component (F) is 0.01 to 30 parts by weight, and (2) the molar ratio of the halogen element to the copper element is 1 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin. Range,

7). 7. The polyamide resin composition according to the above item 6, wherein, when the finely pulverized component (G) is produced, the polyamide resin, the component (E) and the component (F) are previously finely pulverized and melt-kneaded. object,
8). An injection-molded product for a sliding part, which is obtained from the polyamide resin composition according to any one of the above 1 to 7,
9. 9. The injection molded product according to the above item 8, wherein the sliding component is a component selected from a tensioner, a guide, and a cam, a high torque gear and a gear of an endless member for power transmission.
It is.

  The polyamide resin composition of the present invention has excellent melt viscosity during molding and has excellent moldability in which contamination of a mold by a thermal decomposition component is reduced, and the sliding property of the obtained molded article Excellent in abrasion resistance and appearance. In particular, the improvement effect is remarkable in injection molding.

Hereinafter, the present invention will be described in detail.
The molecular weight of the polyamide 66 in the present invention is a molecular weight (RV) determined by measuring according to ASTM D789, and is 80 or more from the viewpoint of abrasion resistance and durability of a molded article, and from the viewpoint of injection moldability and the like. 350 or less. Preferably it is 100 or more and 250 or less, more preferably 100 or more and 200 or less. The molecular weight (RV) is measured at a temperature of 25 ° C. at a concentration of 3 g sample / 30 ml formic acid using 90% formic acid as a solvent.
Polyamide 66 of the present invention includes polyamide 6, polyamide 610, polyamide 612, polyamide 6T (T: terephthalic acid), polyamide 6I (I: isophthalic acid), etc. other than polyamide 66 to the extent that the object of the present invention is not impaired. Other polyamide components may be mixed or copolymerized.

The polyamide 66 of the present invention may contain a copper compound and a halogen compound other than halogen copper as a heat stabilizer. Examples of the copper compound include metal compounds of copper element, for example, copper halide, sulfate, acetate, propionate, benzoate, adipate, terephthalate, salicylate, nicotine And chelate compounds such as ethylenediamine (en) and ethylenediaminetetraacetic acid, and mixtures thereof. Among them, preferred are copper iodide, cuprous bromide, cupric bromide, cuprous chloride and copper acetate.
Such a halogen compound other than copper halide is a salt of iodine with a metal element belonging to Group 1 or 2 of the periodic table, and preferable examples thereof include potassium iodide, sodium iodide, and the like, or a mixture thereof. The most preferable one is potassium iodide.

The compounding amount of the copper compound of the present invention and the halogen compound other than halogen copper is 0.01 or more from the viewpoint of exhibiting the effect of suppressing thermal deterioration with respect to 100 parts by weight of the polyamide, and the amount of metal in the molding machine or on the surface of the molded product is The amount is preferably 1 part by weight, more preferably 0.05 to 0.75 parts by weight, and most preferably 0.05 to 0.5 parts by weight from the viewpoints of copper precipitation and color change due to thermal oxidation deterioration.
In the present invention, the copper compound and a halogen compound other than halogen copper are used in combination, but from the viewpoint that the mold contamination is further improved, the molar ratio of the halogen element to the copper element is in the range of 1 to 50. Preferably, the range of 5 to 30 is more preferable.

  Methods for blending a copper compound and a halogen compound other than halogen copper in polyamide include, for example, a method of blending the compound with a polyamide raw material, a method of blending in a polyamide polymerization process, a method of adhering to a polyamide pellet surface, and a method of melt-kneading polyamide. Any method may be used, such as a method of blending with a polyamide, a method of blending with a polyamide as a master batch, or a method of blending these methods in combination. In the present invention, among these, a method of blending with a polyamide raw material and a method of blending with a polyamide as a master batch can be mentioned as preferred methods.

The heat stabilizer masterbatch of the present invention (hereinafter sometimes referred to as a heat energy masterbatch) is used for improving the dispersibility of the heat stabilizer. Is mixed with a polyamide resin further blended with a dispersant such as a higher fatty acid metal salt, specifically calcium stearate, and then mechanically crushed such as freeze grinding to form a finely ground powder mixture having an average particle size of less than 100 μm. It is obtained by melt-kneading. If the powder particle diameters of the copper compound and the halogen compound other than halogen copper to be compounded are too large, the mechanical properties, particularly toughness, of the obtained molded article are greatly reduced.
In addition, the compounding amount of the copper compound and the halogen compound other than the halogen copper in the heat stabilizer masterbatch of the present invention is 0.01 part by weight or more from the viewpoint of exhibiting the heat stability effect, and is difficult to melt and knead. 30 parts by weight or less. It is preferably 0.5 to 20 parts by weight, more preferably 1 to 15 parts by weight.

  A preferred polymerization method of the polyamide of the present invention is more specifically, a compound of polyamide 66, hexamethylene adipamide, if necessary, a copper compound, an iodine compound other than copper iodine, an antifoaming agent, etc. A hot-melt polycondensation method in which the mixture is concentrated under heating at a temperature of 40 to 300 ° C., and the generated steam pressure is maintained at a pressure between normal pressure and 20 atm. It is. Further, a solid phase polymerization method performed at a temperature equal to or lower than the melting point of the diamine / dicarboxylate solid salt or polycondensate, a solution method in which a dicarboxylate halide component and a diamine component are polycondensed in a solution, and the like can also be used. These methods may be combined as needed. Further, the polymerization form may be a batch type or a continuous type. The polymerization apparatus is not particularly limited, and a known apparatus, for example, an extruder-type reactor such as an autoclave-type reactor, a tumbler-type reactor, or a kneader can be used.

The organic heat stabilizer of the present invention is a heat stabilizer selected from hindered phenols.
The hindered phenols include, for example, pentaeristol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], thiodiethylene-bis [3- (3,5-di- tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N'-hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propioamide], 3,5-bis (1,1-dimethylethyl) -4-hydroxy C7-C9 side chain alkyl ester of benzenepropanoic acid, 2,4 -Dimethyl-6- (1-methylpentadecyl) phenol.

Also, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexane-tert-butyl- 4-a, a ', a "-(mesitylene-2,4,6-tolyl) tri-p-cresol, calcium diethylbis [[[3,5-bis- (1,1-dimethylethyl) -4- [Hydroxyphenyl] methyl] phosphonate], 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate] Is mentioned.
Also, hexamethylene bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione, the reaction product of N-phenylbenzeneamine with 2,4,4-trimethylpentene, -Tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol or a mixture thereof.

The amount of the organic heat stabilizer of the present invention is 0.005 to 0.1 part by weight, preferably 0.01 to 0.1 part by weight, more preferably 0 to 100 parts by weight of the polyamide of the present invention. 0.02 to 0.05 parts by weight. The amount of the organic heat stabilizer to be added is determined from the viewpoints of improvement effects such as mold contamination, occurrence of silvery defects on the surface of the molded product, and toughness.
As the higher fatty acid ester in the present invention, an ester of a higher alcohol and a higher fatty acid, an ester of a polyhydric alcohol and a higher fatty acid, or a mixture thereof is preferably used.

(C-1) Ester of higher alcohol and higher fatty acid As the ester of higher alcohol and higher fatty acid, an ester of an aliphatic alcohol having 8 or more carbon atoms and a higher fatty acid having 8 or more carbon atoms is preferable. Preferably, it is an ester of an aliphatic alcohol having 12 or more carbon atoms and a higher fatty acid having 12 or more carbon atoms, and most preferably, an ester of an aliphatic alcohol having 12 or more carbon atoms and a higher fatty acid having 16 or more carbon atoms. .

Examples of the aliphatic alcohol having 8 or more carbon atoms include octyl alcohol, caprylic alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, lauryl alcohol, tridecyl alcohol, myristine alcohol, pentadecyl alcohol, cetyl alcohol, heptadecyl alcohol, Examples thereof include stearyl alcohol, nonadecyl alcohol, eicosyl alcohol, seryl alcohol, and melisyl alcohol.
Examples of the higher fatty acid having 8 or more carbon atoms include capric acid, uradecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, and lignoceric acid. , Cerotic acid, heptacosanoic acid, montanic acid, melicic acid, lacceric acid and the like.

  Any ester may be used as long as it is an ester composed of the higher alcohol and the higher fatty acid. More preferable higher fatty acid esters include, for example, lauryl laurate, lauryl myristate, lauryl palmitate, lauryl stearate, lauryl behenate, lauryl Lignocerate, lauryl mesylate, myristyl laurate, myristyl myristate, myristyl stearate, myristyl behenate, myristyl lignocerate, myristyl melisate, palmityl laurate, palmityl myristate, palmityl stearate, pal Mytilbehenate, palmityl lignoserate, palmityl melisate, stearyl laurate, stearyl myristate, stearyl palmitate, stearyl stearate, stearyl behene , Stearyl araquinate, stearyl lignoserate, stearyl melisate, eicosyl laurate, eicosyl palmitate, eicosyl stearate, eicosyl behenate, eicosyl lignoserate, eicosyl melissate, behenyl laurate, Behenyl myristate, behenyl palmitate, behenyl stearate, behenyl behenate, behenyl araquinate, behenyl melisate, tetracosanyl laurate, tetracosa palmitate, tetracosanyl stearate, tetracosanyl behenate, tetra Cosanyl lignocerate, tetracosanyl serate, cellotinyl stearate, celloinyl behenate, cellotinyl celloate, mesilyl laurate, mesilyl stearate, mesilyl behenate, melisil Riseto or can mixtures thereof.

(C-2) Ester of Polyhydric Alcohol and Higher Fatty Acid Partial ester of polyhydric alcohol and higher fatty acid is a polyhydric alcohol, for example, glycerin, 1,2,3-butanetriol, 1,2,3-pentanetriol , Erythrit, pentaerythritol, trimethylolpropane, mannitol, sorbitol and the like are preferably used, and as higher fatty acids, for example, capric acid, uradecyl acid, lauric acid, tridecyl acid, myristic acid, pentadecyl acid, palmitic acid, heptadecyl acid , Stearic acid, nonadecanoic acid, arachiic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melicic acid, lacceric acid and the like are preferably used.

  These esters of polyhydric alcohols and higher fatty acids may be any of monoesters, diesters and triesters. More preferred are, for example, higher fatty acid monoglycerides such as glycerin monolaurate, glycerin monomyristate, glycerin monostearate, glycerin monobehenate, glycerin monolignoserate and glycerin monomelisate, pentaerythritol-mono or di-glycerol. Laurate, pentaerythritol-mono or di-laurate, pentaerythritol-mono or di-myristate, pentaerythritol-mono or di-palmitate, pentaerythritol-mono or di-stearate, pentaerythritol-mono or Mono- or di-higher fats of pentaerythritol such as di-behenate, pentaerythritol-mono or di-lignoserate, pentaerythritol-mono or di-melisate Esters, trimethylolpropane-mono- or di-laurate, trimethylolpropane-mono- or di-myristate, trimethylolpropane-mono- or di-palmitate, trimethylolpropane-mono- or di-stearate, trimethylol Mono- or di-higher fatty acid esters of trimethylolpropane, such as propane-mono- or di-behenate, trimethylolpropane-mono- or di-lignoserate, trimethylolpropane-mono- or di-melisate, sorbitan-mono, di- Or tri-laurate, sorbitan-mono, di- or tri-myristate, sorbitan-mono, di- or tri-stearate, sorbitan-mono, di- or tri-behenate, sorbitan-mono, di- or tri-rig Sorbitan-mono, di- or tri-higher fatty acid esters such as serrate, sorbitan-mono, di- or tri-melisate, mannitan-mono, di- or tri-laurate, mannitan-mono, di- or tri-myristate, mannitan-mono, Mannitane- such as di- or tri-palmitate, mannitan-mono, di- or tri-stearate, mannitan-mono, di- or tri-behenate, mannitan-mono, di- or tri-lignocerate, mannitan-mono, di or tri-mericerate. Mono-, di- or tri-higher fatty acid esters or mixtures thereof can be mentioned.

The higher fatty acid ester in the present invention has an acid value of 5 (mg KOH / g) or more from the viewpoint of the effect of improving the mold fouling property and 50 (mg KOH / g) from the viewpoint of preventing the molecular weight from decreasing during molding. mgKOH / g), and the saponification value measured by ASTM D1387 is 50 (mgKOH / g) or more from the viewpoint of the effect of improving mold contamination, and the viewpoint of preventing mold contamination due to deterioration of heat resistance. To 200 (mgKOH / g) or less. The acid value is preferably from 10 to 40, and more preferably from 10 to 30. The saponification value is preferably from 100 to 200, and more preferably from 110 to 180.
The compounding amount of the higher fatty acid ester in the present invention is 0.005 to 0.1 part by weight, preferably 0.01 to 0.1 part by weight, more preferably 100 to 100 parts by weight of the polyamide of the present invention. Is 0.01 to 0.05 parts by weight. The amount of the higher fatty acid ester is determined from the viewpoint of the effect of improving the contamination of the mold and the occurrence of silveriness on the surface of the molded article.

The fatty acid metal salt of the present invention is represented by the following general formula.
CH ₃ (CH ₂ ) _n COO (M)
Here, n = 8 to 32, and the metal element (M) is preferably an element belonging to Group 1, 2, or 3 of the periodic table, zinc, or aluminum. Among them, more preferred are, for example, capric acid, uradecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachinic acid, behenic acid, lignoceric acid, and serotonic acid , Lithium salts, sodium salts, magnesium salts, calcium salts, zinc salts, aluminum salts of heptacosanoic acid, montanic acid, melicic acid and lacceric acid, and mixtures thereof.

The compounding amount of the fatty acid metal salt of the present invention is 0.01 parts by weight or more for the effect of improving plasticization and releasability with respect to 100 parts by weight of the polyamide of the present invention, silvery defects on the surface of the molded product, and molecular weight. 0.1 part by weight or less, preferably from 0.02 to 0.075 part by weight, more preferably from 0.025 to 0.05 part by weight from the viewpoint of prevention of the decrease in the amount of phenol.
The method for producing the polyamide resin composition of the present invention is not particularly limited as long as it is a method of blending an organic heat stabilizer, a higher fatty acid ester, and a higher fatty acid metal salt with a polyamide resin. Organic heat stabilizer and higher fatty acid ester, higher fatty acid metal salt and a mixture thereof are surface-adhered method, and organic heat stabilizer, higher fatty acid ester and higher fatty acid metal salt are mixed with polyamide resin by melt kneader. Melt kneading method, organic heat stabilizer and higher fatty acid ester, masterbatch method of compounding a masterbatch of higher fatty acid metal salt and a mixture thereof with polyamide resin, or a method of combining these methods, etc. May be used.

In the polyamide resin composition of the present invention, to the extent that the object of the present invention is not impaired, additives commonly used in polyamide resins, such as pigments and dyes, flame retardants, lubricants, fluorescent bleaching agents, plasticizers, UV absorbers, nucleating agents, rubbers, other polyamides, resins other than polyamides, and reinforcing agents can also be contained.
The polyamide resin composition of the present invention can be obtained by a known molding method such as press molding, injection molding, gas assist injection molding, welding molding, extrusion molding, blow molding, film molding, hollow molding, multilayer molding, melt spinning, and the like. Even with the plastic molding method used, good molding can be performed. Among them, it is excellent in injection moldability.
The injection-molded product in the present invention is not particularly limited as long as it is a molded product obtained by injection molding, but in particular, a thin-walled molded product such as a binding band, a tag pin or the like requiring a high cycle, or a molded product having a complicated shape, Warping, thin flat or long molded products requiring dimensional characteristics, sliding parts such as gears, gears, shoes, tensioners, guide rails, cams, etc., which require molded product surface smoothness and slidability. is there.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In addition, the physical property evaluation described in the following Examples and Comparative Examples was performed as follows.
1. Characteristics of polyamide resin composition (1-1) Molecular weight (RV) of polyamide
The reaction is performed at a temperature of 25 ° C. at a concentration of 3 g sample / 30 ml formic acid using 90% formic acid as a solvent.
(1-2) Acid Value and Saponification Value of Higher Fatty Acid Ester The acid value conforms to ASTM D1386, and the saponification value conforms to ASTM D1387.

2. Physical properties of polyamide resin composition (2-1) Sublimate generation by thermal decomposition of pellets (visual)
20 g of the dried pellets are placed in a 50 ml glass test tube, and the opening is covered with aluminum foil. Then, the aluminum pellet is set on an aluminum block heater (Taiyo Kagaku Kogyo Co., Ltd. dry thermo unit TAH-1B), and the temperature is set to 200 ° C. And heated for 4 hours. At this time, the state of adhesion of the sublimate adhered to the inner wall surface of the test tube was visually observed.
：: Almost no adhesion is observed △: Intermediate adhesion that can be clearly confirmed ×: A large amount of adhesion

(2-2) Mold Contamination Using an injection molding machine (PS40E manufactured by Nissei Plastics Co., Ltd.), the cylinder temperature was set at 285 ° C., the mold temperature was set at 70 ° C., the injection speed was 35%, the injection was 8 seconds, and the cooling was 10%. The injection molding of the cap-shaped part was performed 100 shots under the injection molding conditions of a molding cycle of 22 seconds and a molding cycle of 22 seconds, and the state of the stain on the gas vent portion of the mold was visually evaluated.
：: Almost no contamination.
Δ: Slightly adhered and stained.
×: considerably adhered and dirty.

(2-3) Sliding characteristics
Using an injection molding machine (FN3000 manufactured by Nissei Plastics Co., Ltd.), the cylinder temperature was set to 290 ° C., the mold temperature was set to 80 ° C., and the evaluation plate (90 mm × 60 mm, 3 mm) was set under the injection conditions of injection 14 seconds and cooling 15 seconds. Thick plate).
In the friction and wear test, the friction coefficient and the amount of wear were measured under the following conditions at room temperature using a pin / plate tester AFT-15MS manufactured by Tosoh Seimitsu Industry Co., Ltd.
Pin material: SUS314
Reciprocating speed: 30 mm / sec Reciprocating distance: 20 mm
Load: 2kg

(2-4) Mechanical Properties Using an injection molding machine (FN3000 manufactured by Nissei Plastics Co., Ltd.), the cylinder temperature was set at 300 ° C., the mold temperature was set at 80 ° C., and the injection molding conditions were 14 seconds for injection and 15 seconds for cooling. A test piece was obtained.
(A) Flexural modulus and flexural strength (MPa)
Performed according to ASTM D790.
(B) Tensile strength (MPa) and tensile elongation (%)
Performed according to ASTM D638.

[Production Example 1]
Production of Polyamide Resin (1) Polyamide 66 raw material (equimolar salt of hexamethylenediamine and adipic acid) is used. A 50% by weight aqueous solution containing 1600 Kg is used, and 60 g of acetic acid and 70 g of a silicone-based antifoaming agent are compounded as a terminal blocking agent. The mixture was charged in an autoclave of about 4000 liters having a discharge nozzle at the bottom, mixed at a temperature of 50 ° C., and replaced with nitrogen. Next, the temperature was raised from 50 ° C. to about 150 ° C. over about 1 hour. At this time, heating was continued while removing water from the system in order to keep the pressure in the autoclave at a gauge pressure of about 0.15 MPa. Further, the autoclave was closed, and the temperature was raised from 150 ° C. to about 220 ° C. over about 1 hour, and the pressure was increased to a gauge pressure of about 1.77 MPa. Thereafter, the temperature was raised from about 220 ° C. to about 280 ° C. over about 1 hour, and heating was performed while removing water outside the system so as to maintain the pressure at about 1.77 MPa. Finally, the pressure was reduced to the atmospheric pressure over about one hour, and after the pressure was reduced to the atmospheric pressure, the polymer was discharged in a strand form from the lower nozzle, water-cooled, and cut to obtain a polyamide resin (1) pellet. The obtained pellets were dried in a nitrogen stream at 90 ° C. for 4 hours. The relative viscosity (RV) of the polyamide pellet was 45. The water content measured by the Karl Fischer method was 0.08% by weight.

[Production Example 2]
Production of Polyamide Resin (2) Polyamide 66 Raw material (equimolar salt of hexamethylenediamine and adipic acid) 50% by weight aqueous solution containing 1600 Kg, a mixture of copper acetate 0.276 kg and potassium iodide 3.17 kg, silicone-based resin 70 g of a foaming agent was blended, charged in an autoclave of about 4000 liters having a discharge nozzle at the bottom, mixed at a temperature of 50 ° C., and replaced with nitrogen. Next, the temperature was raised from 50 ° C. to about 150 ° C. over about 1 hour. At this time, heating was continued while removing water from the system in order to keep the pressure in the autoclave at a gauge pressure of about 0.15 MPa. Further, the autoclave was closed, and the temperature was raised from 150 ° C. to about 220 ° C. over about 1 hour, and the pressure was increased to a gauge pressure of about 1.77 MPa. Thereafter, the temperature was raised from about 220 ° C. to about 280 ° C. over about 1 hour, and heating was performed while removing water outside the system so as to maintain the pressure at about 1.77 MPa. Finally, the pressure was reduced to the atmospheric pressure over about one hour, and after the pressure was reduced to the atmospheric pressure, the polymer was discharged in a strand form from the lower nozzle, water-cooled, and cut to obtain a polyamide resin (2) pellet. The obtained pellets were dried in a nitrogen stream at 90 ° C. for 4 hours. The relative viscosity (RV) of the polyamide pellet was 43. The water content measured by the Karl Fischer method was 0.10% by weight.

[Production Example 3]
Production of Polyamide Resin (3) Four batches of 5 tons of pellets obtained in Production Example 1 were charged into a 10000 L solid-state polymerization apparatus, and nitrogen replacement was sufficiently performed. Thereafter, the heater temperature was set to 220 ° C. using a steam line, and solid-state polymerization was performed while flowing nitrogen at 30,000 L / hour.
At that time, the internal temperature changed from 190 to 200 ° C., heating was stopped after about 15 hours, and the pellets were taken out after cooling. The relative viscosity (RV) of the obtained pellet was 265.

[Production Example 4]
Manufacture of polyamide resin (4) It carried out similarly to manufacture example 3 except having used 5 tons of 4 batches of pellets obtained in manufacture example 2. The molecular weight (RV) of the obtained pellet was 260.

[Production Example 5]
Production of polyamide resin (5) The production was carried out in the same manner as in Production Example 3 except that the heating time for the solid-phase polymerization was changed to 20 hours. The relative viscosity (RV) of the obtained pellet was 380.

[Production Example 6]
Production of polyamide resin (6) A polyamide resin pellet was obtained in the same manner as in Production Example 2, except that a mixture of 0.0276 kg of copper acetate and 0.317 kg of potassium iodide was added. It carried out similarly to manufacture example 3 using this pellet. The molecular weight (RV) of the obtained pellet was 280.

[Production Example 7]
Manufacture of heat-resistant master batch (1) 100 parts by weight of Leona 9200 pellets (polyamide 66/6 copolymer manufactured by Asahi Kasei Chemicals Corporation), 1.5 parts by weight of copper iodide powder, and an average particle diameter previously refined to 20 μm Were mixed with 12 parts by weight of potassium iodide powder and 0.27 parts by weight of calcium stearate powder to prepare a finely powdered mixed powder raw material. This material was melt-kneaded with a twin-screw extruder at a melting temperature of 280 ° C. to obtain a hot-air masterbatch.

[Production Example 8]
Manufacture of Onan masterbatch (2) The procedure was carried out in the same manner as in Production Example 7, except that potassium iodide powder having an average particle size of 500 μm or more was freeze-pulverized and a mixed powder was not prepared in advance.

[Production Example 9]
Manufacture of Hot-An master batch (3) The same procedure as in Production Example 7 was carried out except that 0.05 parts by weight of copper iodide powder and 3 parts by weight of potassium iodide powder were used.

[Production Example 10]
An attempt was made in the same manner as in Production Example 7 except that 5 parts by weight of copper iodide powder and 30 parts by weight of potassium iodide powder were used, but they could not be melt-kneaded and a hot-air masterbatch could not be obtained. .

[Example 1]
Irganox 1098 (N, N'-hexane-1,6-diylbis [3- (3,5-di-produced by Ciba Specialty Chemicals), based on 100 parts by weight of the polyamide resin (3) pellets of Production Example 3. -Tert-butyl-4-hydroxyphenyl) propioamide]), 0.05 parts by weight of Licowax-E (Montanate ester wax manufactured by Clariant Japan K.K.), SA-1500 (Sakai Chemical Industry Co., Ltd. 0.05 parts by weight of an aluminum distearate manufactured by K.K.) and 0.05 parts by weight of a spreading agent (PEG-400 manufactured by Nippon Oil & Fats Co., Ltd.) using a tumbler to mix the polyamide resin composition. Obtained. Table 1 shows the evaluation results.

[Example 2]
Irganox 1098 (N, N'-hexane-1,6-diylbis [3- (3,5-di-produced by Ciba Specialty Chemicals), based on 100 parts by weight of the polyamide resin (4) pellets of Production Example 4. -Tert-butyl-4-hydroxyphenyl) propioamide]), 0.025 part by weight of Licowax-E (Montanate ester wax manufactured by Clariant Japan K.K.), SA-1000 (Sakai Chemical Industry Co., Ltd.) Using a tumbler so that 0.05 parts by weight of aluminum monostearate (manufactured by K.K.) and 0.03 parts by weight of a spreading agent (PEG-400 manufactured by NOF CORPORATION) are mixed together to obtain a polyamide resin composition. Got. Table 1 shows the evaluation results.

[Example 3]
It carried out like Example 2 except adding 5 weight part of black coloring master batches. Table 1 shows the evaluation results.

[Comparative Example 1]
It carried out similarly to Example 1 except having used the polyamide resin (1) of the manufacture example 1 instead of the polyamide resin (3). Table 1 shows the evaluation results.

[Comparative Example 2]
It carried out similarly to Example 1 except having used the polyamide resin (5) of the manufacture example 5 instead of the polyamide resin (3). Table 1 shows the evaluation results.

[Comparative Example 3]
It carried out similarly to Example 1 except not adding Irganox1098. Table 1 shows the evaluation results.

[Comparative Example 4]
It carried out like Example 1 except not adding Licowax-E. Table 1 shows the evaluation results.

[Comparative Example 5]
It carried out like Example 1 except not adding SA-1500. Table 1 shows the evaluation results.

[Example 4]
The procedure was carried out in the same manner as in Example 3 except that a twin screw extruder (TEM35 manufactured by Toshiba Machine Co., Ltd.) was used instead of a tumbler and melt-kneaded at 290 ° C. to obtain a polyamide resin composition. Table 1 shows the evaluation results.

[Example 5]
Instead of Irganox 1098, 0.1 part by weight of Irganox 1010 (pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] manufactured by Ciba Specialty Chemicals Co., Ltd.) And Licowax-E in place of Licowax-OP (partially saponified montanic acid ester wax manufactured by Clariant Japan KK) in an amount of 0.05 part by weight.

[Example 6]
The procedure was performed in the same manner as in Example 2 except that the polyamide resin (6) pellets of Production Example 6 were used. The evaluation results are shown in Table 2.

[Example 7]
The procedure was performed in the same manner as in Example 1 except that 100 parts by weight of the polyamide resin (3) pellets of Production Example 3 were further mixed with 3 parts by weight of the pellets of the heat-resistant masterbatch (1) of Production Example 7. The evaluation results are shown in Table 2.

[Comparative Example 6]
Example 8 was carried out in the same manner as in Example 6, except that the hot-air masterbatch (2) of Production Example 8 was used. The evaluation results are shown in Table 2.

[Comparative Example 7]
Example 6 was carried out in the same manner as in Example 6, except that the hot-air masterbatch (3) of Production Example 9 was used. The evaluation results are shown in Table 2.

  Thin-walled molded products such as binding bands and tag pins that require high cycles, molded products with complicated shapes, warpage, thin-walled flat and long molded products that require dimensional characteristics, molded product surface smoothness and slidability Is preferably used for sliding parts such as gears, gears, shoes, tensioners, guide rails, cams, etc., which require the following.

Claims (9)

  0.005 to 0.1 parts by weight of an organic heat stabilizer (B) selected from hindered phenols, based on 100 parts by weight of a high molecular weight polyamide 66 (A) having a relative viscosity RV of 80 to 350, 0.005 to 0.1 parts by weight of a higher fatty acid ester (C) having a value of 5 to 50 (mgKOH / g) and a saponification value of 50 to 200 (mgKOH / g), and 0.1 to 0.1 parts by weight of a higher fatty acid metal salt (D). A polyamide resin composition comprising from 0.1 to 0.1 part by weight.   The polyamide resin composition according to claim 1, wherein the component (B), the component (C), and the component (D) adhere to the surface of the pellet of the component (A). The polyamide resin composition according to claim 1, wherein the component (A) contains a copper compound (E) and a halogen compound (F) other than halogen copper as a heat stabilizer. 4.
However, (1) the total amount of the component (E) and the component (F) is 0.01 to 1 part by weight with respect to 100 parts by weight of the component (A),
(2) The molar ratio between the halogen element and the copper element is in the range of 1 to 50.   The heat stabilizer master batch (G) comprising a polyamide resin, a component (E) and a component (F) is compounded in an amount of 0.1 to 100 parts by weight with respect to 100 parts by weight of the component (A). The polyamide resin composition according to any one of claims 1 to 3.   The polyamide resin composition according to claim 4, wherein the component (B), the component (C) and the component (D) are attached to the surface of the pellet of the component (A) and the component (G). The polyamide resin composition according to claim 4, wherein the component (G) contains a component (E) and a component (F) as a heat stabilizer.
However, (1) the total amount of the component (E) and the component (F) is 0.01 to 30 parts by weight, and (2) the molar ratio of the halogen element to the copper element is 1 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin. Range.   7. The polyamide resin according to claim 6, wherein, in producing the finely pulverized component (G), a polyamide resin, a component (E) and a component (F) which have been finely pulverized are melt-kneaded. Composition.   An injection-molded article for a sliding part, obtained from the polyamide resin composition according to claim 1.   The injection molded product according to claim 8, wherein the sliding component is a component selected from a tensioner, a guide, and a cam, a high torque gear, and a gear of an endless member for power transmission.