JP5639381B2 - Glass fiber reinforced polyamide resin composition - Google Patents

Description

  The present invention relates to a glass fiber reinforced polyamide resin composition.

  Polyamide resins and polyester resins are used in various industrial fields because they have excellent mechanical properties (such as mechanical strength, rigidity, and impact resistance). Of these, polyamide is often used in combination with an inorganic compound filler such as glass fiber, glass flake, alumina fiber or layered inorganic compound for the purpose of enhancing mechanical properties. Among these, when compounding with glass fiber as an inorganic compound, a silane coupling agent or a film forming agent is generally used to modify the interface state when compounded with polyamide.

  Furthermore, in order to further improve the mechanical properties of the polyamide resin, a technique relating to a glass fiber reinforced polyamide resin composition has attracted attention. For example, polyamide is compounded with a glass fiber surface-treated with a glass fiber sizing agent containing a maleic anhydride and unsaturated monomer copolymer and a silane coupling agent as main components. Thereby, the technique of improving antifreeze liquid resistance is disclosed (patent document 1). Moreover, the technique which improves the fluidity | liquidity of the glass fiber in molten resin is disclosed by using the compound which introduce | transduced the allyl group into the terminal of a silane coupling agent (patent document 2). Furthermore, the technique which improves the water resistance of a glass fiber surface and a polyamide resin using polycarbodiimide resin, a polyurethane resin, and a silane coupling agent is disclosed (patent document 3).

JP-A-6-128479 JP 2000-303359 A JP-A-9-227173

  However, when a polyamide resin composition is used for automobile parts, various electronic parts, etc., mechanical strength at high temperatures, toughness, heat resistance, and workability are required at a high level. However, it is difficult to stably obtain a polyamide resin composition that reaches such a level with the conventional techniques described above. Therefore, the request | requirement with respect to the stable supply of the glass fiber reinforced polyamide resin composition applicable to said components is increasing.

  Then, the subject of this invention is providing the glass fiber reinforced polyamide resin composition excellent in the mechanical strength at high temperature, toughness, heat resistance, and workability.

  The present inventors have intensively studied to solve the above problems. As a result, the inventors have found that the above problems can be solved by using a glass fiber reinforced polyamide resin composition containing a polyamide resin having a predetermined condition and containing a predetermined glass fiber, and completed the present invention.

  That is, the glass fiber reinforced polyamide resin composition according to the present invention is a glass fiber reinforced polyamide resin composition comprising (A) a polyamide resin and (B) a glass fiber containing a glass fiber sizing agent containing a polycarbodiimide compound. In the component (A), the ratio of the amino group terminal concentration to the carboxyl group terminal concentration exceeds 0.63.

  In one embodiment of the present invention, the carboxyl group terminal concentration of the component (A) is preferably 50 μmol / g or more.

  In another aspect of the present invention, the component (B) is preferably 1 to 200 parts by mass with respect to 100 parts by mass of the component (A).

  According to the present invention, a glass fiber reinforced polyamide resin composition excellent in mechanical strength, toughness, heat resistance and processability at high temperatures can be obtained.

  Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. In addition, this invention is not restrict | limited to the following embodiment, In the range of the summary, various deformation | transformation can be implemented.

  The present embodiment is a glass fiber reinforced polyamide resin composition comprising (A) a polyamide resin and (B) a glass fiber containing a glass fiber sizing agent containing a polycarbodiimide compound, the component (A) Among them, the ratio of the amino group terminal concentration to the carboxyl group terminal concentration is more than 0.63, and relates to a glass fiber reinforced polyamide resin composition.

  Hereinafter, each component of the glass fiber reinforced polyamide resin composition will be described in detail.

[(A) Polyamide resin]
Polyamide means a polymer compound having a —CO—NH— (amide) bond in the main chain. Although not limited to the following, for example, polyamide obtained by ring-opening polymerization of lactam, polyamide obtained by self-condensation of ω-aminocarboxylic acid, polyamide obtained by condensing diamine and dicarboxylic acid, and copolymers thereof Is mentioned. Polyamide may be used alone or as a mixture of two or more. Hereinafter, the raw material of the (A) polyamide resin in the present embodiment will be described.

  The lactam as a monomer which is a constituent component of polyamide is not limited to the following, and examples thereof include pyrrolidone, caprolactam, undecaractam and dodecaractam. On the other hand, the ω-aminocarboxylic acid is not limited to the following, and examples thereof include ω-amino fatty acid which is a ring-opening compound of the above lactam with water. In addition, as lactam or ω-aminocarboxylic acid, two or more monomers may be used together and condensed.

  Next, the polyamide obtained by condensing diamine and dicarboxylic acid will be described. First, the diamine (monomer) is not limited to the following. For example, a linear aliphatic diamine such as hexamethylene diamine or pentamethylene diamine; 2-methylpentane diamine or 2-ethylhexamethylene diamine Branched aliphatic diamines such as: aromatic diamines such as p-phenylenediamine and m-phenylenediamine; and alicyclic diamines such as cyclohexanediamine, cyclopentanediamine and cyclooctanediamine. On the other hand, the dicarboxylic acid (monomer) is not limited to the following, but examples thereof include aliphatic dicarboxylic acids such as adipic acid, pimelic acid and sebacic acid; aromatic dicarboxylic acids such as phthalic acid and isophthalic acid; cyclohexane And alicyclic dicarboxylic acids such as dicarboxylic acids. The diamines and dicarboxylic acids as the above-described monomers may be condensed individually by one kind or in combination of two or more kinds.

  Examples of the polyamide include, but are not limited to, polyamide 4 (poly α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecanamide), polyamide 12 (polydodecanamide), and polyamide 46 (polytetraamide). Methylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610, polyamide 612, polyamide 6T (polyhexamethylene terephthalamide), polyamide 9T (polynonamethylene terephthalamide), polyamide 6I (polyhexamethylene isophthalamide) Amide), polyamide 2Me5C (polycondensate of 2-methylpentamethylenediamine and 1,4-cyclohexanedicarboxylic acid), and a copolymerized polyamide containing at least one of these as a constituent component It is below. Among them, preferably selected from the group consisting of polyamide 6, polyamide 66, polyamide 610, polyamide 612, polyamide 6T, polyamide 6I, polyamide 9T, and polyamide 2Me5C, and a copolymerized polyamide containing at least one of these as a constituent component. One or more.

  The polyamide that is a copolymer is not limited to the following, but includes, for example, a copolymer of hexamethylene adipamide and hexamethylene terephthalamide, a copolymer of hexamethylene adipamide and hexamethylene isophthalamide, Copolymers of amide and 2-methylpentanediamine terephthalamide, polycondensate of 2-methylpentamethylenediamine and 1,4-cyclohexanedicarboxylic acid, and polycondensate of 2-methylpentamethylenediamine and sebacic acid. Examples thereof include a polymer, a polycondensate of 2-methylpentamethylenediamine and 1,4-cyclohexanedicarboxylic acid, and a copolymer of a polycondensate of 2-methylpentamethylenediamine and dodecanedioic acid.

  In general, an amino group or a carboxyl group is present as an end group of the polyamide in the present embodiment. In the present embodiment, the ratio of these terminal groups is determined from the viewpoint of improving mechanical strength, toughness (bending deflection), heat resistance and workability of the composition at high temperatures, and amino group terminal concentration / carboxyl terminal concentration. Becomes a value exceeding 0.63. Here, “high temperature” in the present specification means 50 ° C. or higher.

  The lower limit of amino group terminal concentration / carboxyl terminal concentration is preferably 0.65 or more, more preferably 0.7 or more. On the other hand, the upper limit of amino group terminal concentration / carboxyl terminal concentration is preferably 2.5 or less, more preferably 2.0 or less. In the case of the above range, the fluidity of the glass fiber reinforced polyamide resin composition is further improved.

  The concentration of the terminal carboxyl group is preferably 30 μmol / g or more, more preferably 50 μmol / g or more, still more preferably 50 to 150 μmol / g, and particularly preferably 50 to 100 μmol / g. When the concentration of the terminal carboxyl group is within the above range, the mechanical strength can be significantly improved.

Here, as a measuring method of the concentration of the terminal amino group and the terminal carboxyl group in the present specification, a method for determining by an integral value of a characteristic signal corresponding to each terminal group, measured by ¹ H-NMR, or a titration method. The way you ask can be.

  Furthermore, the end group of the polyamide resin may be adjusted separately. As the adjustment method, a known method can be used. Although it does not restrict | limit to the following, For example, the method of using a terminal regulator is mentioned. As a specific example, at least one selected from the group consisting of a monoamine compound, a diamine compound, a monocarboxylic acid compound, and a dicarboxylic acid compound can be added so as to have a predetermined terminal concentration during polymerization of the polyamide resin. The addition timing of these components to the solvent is not particularly limited as long as it functions originally as a terminal regulator, and for example, the above-described polyamide resin raw material may be added to the solvent.

  Examples of the monoamine compound include, but are not limited to, aliphatics such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine. Examples include monoamines; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine, and any mixtures thereof. Of these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are preferable from the viewpoints of reactivity, boiling point, stability of the sealing end and price.

  The above-mentioned illustrations can be cited as they are for the diamine compound.

  Examples of the monocarboxylic acid compound include, but are not limited to, for example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecyl acid, myristic acid, palmitic acid, stearic acid, and pivalic acid. And aliphatic monocarboxylic acids such as isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid Aromatic monocarboxylic acids are mentioned. In this Embodiment, these carboxylic acid compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

  Examples of the dicarboxylic acid compound include, but are not limited to, for example, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethyl Aliphatic dicarboxylic acids such as glutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; Isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, Diphenylmethane-4,4′-dicarboxylic acid, diphenylsulfone-4,4′-dicarbo Units derived from an aromatic dicarboxylic acid such as an acid and 4,4'-biphenyl dicarboxylic acid (unit) and the like. These can be used either alone or in combination of two or more.

[(B) Glass fiber containing glass fiber sizing agent containing polycarbodiimide compound]
The glass fiber used for this Embodiment contains the glass fiber sizing agent containing a polycarbodiimide compound. More specifically, the glass fiber is obtained by surface treatment with the sizing agent. The polycarbodiimide compound is obtained by condensing a compound containing one or more carbodiimide groups (—N═C═N—).

  The degree of condensation of the polycarbodiimide is preferably 1-20, and more preferably 1-10. When the degree of condensation is in the range of 1 to 20, a good aqueous solution or aqueous dispersion can be obtained. Furthermore, when the condensation degree is in the range of 1 to 10, a better aqueous solution or aqueous dispersion can be obtained.

  Moreover, it is preferable that it is a polycarbodiimide compound which has a polyol segment partially. By having a polyol segment, the polycarbodiimide compound is easily water-soluble and can be more suitably used as a glass fiber sizing agent.

  These carbodiimide compounds can be obtained by decarboxylating a diisocyanate compound in the presence of a known carbodiimidization catalyst such as 3-methyl-1-phenyl-3-phospholene-1-oxide. As the diisocyanate compound, aromatic diisocyanates, aliphatic diisocyanates and alicyclic diisocyanates, and mixtures thereof can be used. Although not limited to the following, for example, 1,5-naphthalene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4 -Tolylene diisocyanate, 2,6-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, hexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate , Dicyclohexylmethane-4,4′-diisocyanate, methylcyclohexane diisocyanate, tetramethylxylylene diisocyanate, 2,6-diisopropylphenyl Such as isocyanate and 1,3,5-triisopropylbenzene 2,4-diisocyanate. And the polycarbodiimide compound which has two isocyanate groups at the terminal is obtained by carbodiimidizing these diisocyanate compounds. Of these, dicyclohexylmethane carbodiimide can be suitably used from the viewpoint of improving reactivity.

  With respect to the polycarbodiimide compound having two isocyanate groups at the terminal, a method in which a monoisocyanate compound is carbodiimidized in an equimolar amount, or a method in which an equimolar amount is reacted with a polyalkylene glycol monoalkyl ether to form a urethane bond, etc. A polycarbodiimide compound having one isocyanate group at the terminal is obtained. Examples of the monoisocyanate compound include, but are not limited to, hexyl isocyanate, phenyl isocyanate, cyclohexyl isocyanate, and the like. The polyalkylene glycol monoalkyl ether described above is not limited to the following, and examples thereof include polyethylene glycol monomethyl ether and polyethylene glycol monoethyl ether.

  In addition to the polycarbodiimide compound, as the glass fiber sizing agent, polyurethane resin, homopolymer of acrylic acid, copolymer of acrylic acid and other copolymerizable monomers, and primary, secondary and tertiary of these. A salt with an amine and a copolymer containing a carboxylic anhydride-containing unsaturated vinyl monomer and another unsaturated vinyl monomer may also be included. These can be used alone or in combination of two or more.

  The polyurethane resin is not particularly limited as long as it is generally used as a glass fiber sizing agent for glass fibers. For example, m-xylylene diisocyanate (XDI), 4,4′-methylenebis (cyclohexyl isocyanate) ( Those synthesized from an isocyanate such as HMDI) or isophorone diisocyanate (IPDI) and a polyester or polyether diol can be suitably used.

  As a homopolymer of acrylic acid, the weight average molecular weight is preferably 1,000 to 90,000, more preferably 1,000 to 25,000. In addition, the measuring method of the weight average molecular weight in this specification is the value measured by GPC.

  The polymer of acrylic acid may be a copolymer of acrylic acid and other copolymerizable monomers. The monomer that forms the copolymer with acrylic acid is not limited to the following, but examples of the monomer having a hydroxyl group and / or a carboxyl group include acrylic acid, maleic acid, methacrylic acid, vinyl acetic acid, crotonic acid, and isocrotone. One or more types selected from the group consisting of acid, fumaric acid, itaconic acid, citraconic acid and mesaconic acid are mentioned (except for the case of acrylic acid only). Preferably, it has 1 or more types of ester monomers among the above-mentioned monomers.

  Polymers of acrylic acid (including both homopolymers and copolymers) may be in salt form. The salt of acrylic acid polymer includes, but is not limited to, primary, secondary, or tertiary amines. Although not limited to the following, specific examples include triethylamine, triethanolamine, and glycine. The degree of neutralization is preferably 20 to 90%, preferably 40 to 60% from the viewpoint of improving the stability of the mixed solution with other concomitant drugs (such as a silane coupling agent) and reducing the amine odor. Is more preferable.

  The weight average molecular weight of the acrylic acid polymer forming the salt is not particularly limited, but is preferably in the range of 3,000 to 50,000. 3,000 or more are preferable from the viewpoint of improving the converging property of the glass fiber, and 50,000 or less are preferable from the viewpoint of improving the mechanical properties when the resin composition is obtained.

  Among the copolymers comprising a carboxylic acid anhydride-containing unsaturated vinyl monomer and other unsaturated vinyl monomers, the carboxylic acid anhydride-containing unsaturated vinyl monomer is particularly limited. There is nothing. Examples thereof include maleic anhydride, itaconic anhydride and citraconic anhydride, and maleic anhydride is particularly preferable. On the other hand, the unsaturated vinyl monomer is not limited to, for example, styrene, α-methylstyrene, ethylene, propylene, butadiene, isoprene, chloroprene, 2,3-dichlorobutadiene, 1,3-pentadiene, Examples include cyclooctadiene, methyl methacrylate, methyl acrylate, ethyl acrylate, and ethyl methacrylate. Of these, styrene and butadiene are preferred.

  Among these combinations, a copolymer of maleic anhydride and butadiene, a copolymer of maleic anhydride and ethylene, a copolymer of maleic anhydride and styrene, and a mixture thereof are more preferable.

  The copolymer of the carboxylic acid anhydride-containing unsaturated vinyl monomer and other unsaturated vinyl monomer preferably has a weight average molecular weight of 2,000 or more. Moreover, from a viewpoint of the fluidity | liquidity improvement of a glass fiber reinforced polyamide resin composition, More preferably, it is 2,000-1,000,000, More preferably, it is 5,000-500,000.

  It is also preferable to use a silane coupling agent as the surface treatment agent for glass fibers. Although it does not restrict | limit especially as said silane coupling agent, For example, aminosilanes, such as (gamma) -aminopropyl triethoxysilane, (gamma) -aminopropyl trimethoxysilane, and N- (beta)-(aminoethyl) -gamma-aminopropylmethyldimethoxysilane. And the like; mercaptosilanes such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane; epoxysilanes; vinylsilanes. Especially, it is preferable that it is 1 or more types selected from said enumeration component, and aminosilanes are more preferable.

  It is preferable to use a lubricant when preparing the glass fiber sizing agent. As the lubricant, any normal liquid or solid lubricant material suitable for the purpose can be used. Although not limited to the following, surfactants such as animal and plant or mineral waxes such as carnauba wax and lanolin wax, or fatty acid amides, fatty acid esters or fatty acid ethers, or aromatic esters or aromatic ethers may be used. It can be used.

  The glass fiber sizing agent used in this embodiment has a solid content of 1 to 5% by weight of a polycarbodiimide compound, 1 to 5% by weight of a polyurethane resin, 0.1 to 1% by weight of a silane coupling agent, and 0 lubricant. It is preferable to prepare the glass fiber sizing agent by diluting 0.01 to 0.5% by mass with water and adjusting the total mass to 100% by mass.

  Further, if desired, a homopolymer of acrylic acid or a copolymer of acrylic acid and other monomer components is preferably 1 to 10% by mass, more preferably 2 to 5% by mass, and an active amino group in the main chain skeleton. The reactive polyurethane resin is preferably 1 to 5% by mass, more preferably 2 to 4% by mass, and a copolymer of a carboxylic acid anhydride-containing unsaturated vinyl monomer and another unsaturated vinyl monomer is preferable. May be contained in an amount of 1 to 5% by mass, more preferably 2 to 4% by mass.

  The blending amount of the polycarbodiimide compound with respect to 100% by mass of the glass fiber sizing agent is preferably 1% by mass or more from the viewpoint of improving the mechanical strength of the glass fiber reinforced polyamide resin composition. In view of the above, it is preferably 5% by mass or less. The blending amount of the polyurethane resin is preferably 1% by mass or more with respect to 100% by mass of the glass fiber sizing agent, from the viewpoint of improving the sizing property of the glass fiber, and the mechanical strength of the glass fiber reinforced polyamide resin composition. From the viewpoint of improvement, it is preferably 5% by mass or less.

  Selected from homopolymers of acrylic acid and copolymers of acrylic acid with other monomer components and their primary, secondary and tertiary amine salts, based on 100% by weight of the glass fiber sizing agent The blending amount of the one or more polymers is preferably 1% by mass or more from the viewpoint of improving the mechanical strength of the glass fiber reinforced polyamide resin composition at the time of water absorption in a field requiring water resistance strength. From the viewpoint of improving the color tone, appearance and surface smoothness of the composition, the content is preferably 10% by mass or less.

  Next, the blending amount of the silane coupling agent in the glass fiber sizing agent is preferably 0.1 to 1% by mass from the viewpoint of improving the glass fiber sizing property and improving the mechanical strength of the glass fiber reinforced polyamide resin composition. . Further, the blending amount of the lubricant in the glass fiber sizing agent is preferably 0.01% by mass or more from the viewpoint of providing sufficient lubricity, and a viewpoint of improving the mechanical strength of the glass fiber reinforced polyamide resin composition. To 0.5% by mass or less.

  The glass fiber is continuous by drying the glass fiber strand produced by applying the glass fiber sizing agent to the glass fiber using a known method such as a roller-type applicator in the known glass fiber production process. Obtained by reaction. The glass fiber strand may be used as a roving as it is, or may be used as a chopped glass strand after further obtaining a cutting step. Such a glass fiber sizing agent preferably imparts (adds) a solid content of 0.2 to 3% by mass, more preferably 0.3 to 2% by mass (adds) to 100% by mass of glass fiber. ) From the standpoint of maintaining the glass fiber bundling, the addition amount of the glass fiber bundling agent is preferably 0.2% by mass or more as a solid content with respect to 100% by mass of the glass fiber. On the other hand, it is preferably 3% by mass or less from the viewpoint of improving the thermal stability of the glass fiber reinforced polyamide resin composition. The strand may be dried after the cutting step, or may be cut after the strand is dried.

  Here, with respect to 100 parts by mass of the component (A) (polyamide resin) described above, the content of the component (B) (predetermined glass resin) is preferably 1 to 200 parts by mass, and more preferably. Is 5 to 150 parts by mass, and more preferably 15 to 100 parts by mass. When it is within the above range, both the fluidity and appearance of the glass fiber reinforced polyamide resin composition tend to be more excellent.

[Lubricant]
In the glass fiber reinforced polyamide resin composition according to the present embodiment, a lubricant may be further added. Although it does not restrict | limit especially as a lubricant, As a preferable lubricant, a monoamide compound, a substituted amide compound, a methylol amide compound, a bisamide compound, etc. are mentioned. More preferred is a bisamide compound. Among the bisamide compounds, ethylene bis stearic acid amide is particularly preferable.

  When using a lubricant, the blending amount of the lubricant in the glass fiber reinforced polyamide resin composition is preferably 0.05 to 5 parts by mass, more preferably 0.2 to 2 parts by mass with respect to 100 parts by mass of the polyamide resin. Part. When it is within the above range, the plasticization stability is further improved and the amount of generated gas tends to be reduced.

[Other components that can be contained in the glass fiber reinforced polyamide resin composition]
In addition to the above-described components, other components may be added as necessary within a range not impairing the effects of the present embodiment.

  Although not limited to the following, for example, inorganic fillers other than glass fibers, antioxidants, ultraviolet absorbers, heat stabilizers, light deterioration inhibitors, plasticizers, mold release agents, nucleating agents, flame retardants, colorants, dyeing An agent or pigment may be added, or other thermoplastic resin may be mixed. Here, since the above-mentioned other components are greatly different in properties, there are various suitable contents for each component that hardly impair the effects of the present embodiment. A person skilled in the art can easily set a suitable content for each of the other components described above.

  In the present embodiment, the method of compounding the glass fiber and the polyamide resin may be a method of kneading the polyamide resin in a melted state using a single-screw or multi-screw extruder. When using chopped strands, use a twin screw extruder equipped with an upstream supply port and a downstream supply port. After feeding and melting polyamide resin from the upstream supply port, chopped strands from the downstream supply port It is preferable to use a method of supplying and melt kneading. Moreover, also when using glass fiber roving, it can compound by a well-known method.

  The resin composition as the target product thus obtained is not particularly limited, and can be used, for example, as a molded body of various parts by injection molding.

  These various parts can be suitably used, for example, for automobiles, machine industries, electrical / electronics, industrial materials, industrial materials, and daily / household goods. Among them, it is suitable as an underhood part for automobiles that are used at high temperatures.

  Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples, but the present embodiment is not limited to only these examples.

[Preparation of raw materials]
1. Polyamide resin (1) Polyamide 66 (hereinafter abbreviated as “PA-1”)

  1600 kg of equimolar salt of hexamethylenediamine (manufactured by Asahi Kasei Chemicals) and adipic acid (manufactured by Asahi Kasei Chemicals) as a polyamide raw material was added to distilled water to obtain a 50% by mass aqueous solution as a polyamide raw material. The obtained aqueous solution was charged into an autoclave of about 4,000 liters having a discharge nozzle at the bottom, and replaced with nitrogen while mixing at 50 ° C.

  Subsequently, the temperature was raised from 50 ° C. to about 150 ° C. over about 1 hour. At that time, in order to keep the pressure in the autoclave at about 0.15 MPa (gauge pressure), heating was continued while removing water out of the system. Thereafter, the autoclave was sealed, and the temperature was raised from 150 ° C. to about 220 ° C. over about 1 hour to raise the pressure to about 1.77 MPa (gauge pressure).

  Subsequently, the temperature was raised from about 220 ° C. to about 280 ° C. over about 1 hour, while maintaining the pressure at about 1.77 MPa, heating was performed by removing water from the system. Thereafter, the pressure was reduced to atmospheric pressure over about 1 hour, and after reaching atmospheric pressure, the pellets were discharged in a strand form from the lower nozzle, water-cooled and cut to obtain PA-1 pellets. The obtained pellets were dried in a nitrogen stream at 90 ° C. for 4 hours.

PA-1 had a 98% sulfuric acid relative viscosity [ηr: 25 ° C., 1 g / 100 ml] of 2.79. The amino group terminal was 46 μmol / g, the carboxyl group terminal was 72 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 0.639. In addition, the measurement of the terminal group was carried out by measuring ¹ H-NMR at 60 ° C. using a bisulfate solvent and calculating from the integrated value (hereinafter also referred to as “NMR method”). Further, JIS K 6920 was adopted as a method for measuring sulfuric acid relative viscosity in the present specification.

(2) Polyamide 66 (hereinafter abbreviated as “PA-2”)
PA-2 was obtained in the same manner as in the case of PA-1 except that 0.5 kg of hexamethylenediamine was added as a terminal adjusting agent. Here, ηr was 2.78, the amino group terminal was 50 μmol / g, the carboxyl group terminal was 67 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 0.746. In addition, the terminal group was calculated | required by the said NMR method.

(3) Polyamide 66 (hereinafter abbreviated as “PA-3”)
PA-3 was obtained in the same manner as in the case of PA-2 except that the amount of hexamethylenediamine added as a terminal modifier was changed to 1.5 kg. Here, ηr was 2.78, the amino group terminal was 58 μmol / g, the carboxyl group terminal was 62 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 0.935. In addition, the terminal group was calculated | required by the said NMR method.

(4) Polyamide 66 (hereinafter abbreviated as “PA-4”)
PA-4 was obtained in the same manner as in the case of PA-1 except that 1.0 kg of adipic acid was added as a terminal regulator. Here, ηr was 2.78, the amino group terminal was 42 μmol / g, the carboxyl group terminal was 79 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 0.532. In addition, the terminal group was calculated | required by the said NMR method.

(5) Polyamide 66 (hereinafter abbreviated as “PA-5”)
PA-5 was obtained in the same manner as in the case of PA-2 except that the amount of hesamethylenediamine as a terminal modifier was changed to 6.4 kg. Here, ηr was 2.75, the amino group terminal was 80 μmol / g, the carboxyl group terminal was 37 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 2.162. In addition, the terminal group was calculated | required by the said NMR method.

(6) Polyamide 2Me5C (hereinafter abbreviated as “PA-6”)
604 g (5.20 mol) of 2-methylpentamethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 896 g (5.20 of 1,4-cyclohexanedicarboxylic acid (manufactured by Eastman Chemical Co., Ltd .: trade name 1,4-CHDA HP grade) Mol) was dissolved in 1,500 g of distilled water to make an equimolar 50 mass% homogeneous aqueous solution of the raw material monomer.

The obtained aqueous solution and 24 g (0.21 mol) of 2-methylpentamethylenediamine, which is an additive at the time of melt polymerization, were charged into an autoclave (made by Nitto High Pressure Co., Ltd.) having an internal volume of 5.4 L, and the liquid temperature (internal temperature) ) Was kept at 50 ° C., and the autoclave was purged with nitrogen. The liquid temperature was continuously heated from about 145 ° C. until the pressure in the autoclave tank reached about 2.5 kg / cm ² as gauge pressure (hereinafter, all pressure in the tank was expressed as gauge pressure). . In order to keep the pressure in the tank at about 2.5 kg / cm ² , heating was continued while removing water out of the system, and the solution was concentrated until the concentration of the aqueous solution became about 75%. The removal of water was stopped, and heating was continued until the pressure in the tank reached about 30 kg / cm ² . In order to keep the pressure in the tank at 30 kg / cm ² , heating was continued until the temperature reached 315 ° C. while removing water out of the system. While further heating, the pressure in the tank was reduced from 30 kg / cm ² to atmospheric pressure (gauge pressure was 0 kg / cm ² ) over 100 minutes.

Thereafter, the heater temperature was adjusted so that the final temperature of the resin temperature (liquid temperature) in the tank was 345 ° C. The resin temperature was kept at 345 ° C., and the inside of the tank was maintained under a reduced pressure of 1.33 × 10 ⁴ Pa (100 torr) for 10 minutes by a vacuum apparatus. Thereafter, the inside of the tank was pressurized with nitrogen, and the resin was discharged in a strand form from the lower nozzle (nozzle). Furthermore, the strand-shaped resin was cooled with water, cut, and discharged in the form of pellets to obtain PA-6 pellets. The obtained pellets were dried at 120 ° C. for 10 hours in a nitrogen stream. Here, the amino group terminal was 52 μmol / g, the carboxyl group terminal was 32 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 1.625. In addition, the measurement of each terminal group density | concentration was calculated | required by the titration method similar to the Example of Unexamined-Japanese-Patent No. 2003-119376 as follows.
<Amino group terminal concentration measurement method>
After dissolving 2 g of polyamide resin in 50 mL of phenol at 60 ° C., 40 mL of ethanol and 10 mL of pure water were added and titrated with 0.01 N HCl using a potentiometric titrator GT-06 manufactured by Mitsubishi Chemical Corporation.
<Measurement method of carboxyl group end concentration>
After dissolving 0.1 g of polyamide resin in 8 mL of benzyl alcohol at 180 ° C., titration was performed with 0.01 N NaOH / benzyl alcohol using phenol red as an indicator.

(7) Polyamide 2Me5C (hereinafter abbreviated as “PA-7”)
604 g (5.20 mol) of 2-methylpentamethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 896 g (5.20 of 1,4-cyclohexanedicarboxylic acid (manufactured by Eastman Chemical Co., Ltd .: trade name 1,4-CHDA HP grade) Mol) was dissolved in 1,500 g of distilled water to make an equimolar 50 mass% homogeneous aqueous solution of the raw material monomer.

The obtained aqueous solution and 15 g (0.13 mol) of 2-methylpentamethylenediamine, which is an additive at the time of melt polymerization, were charged into an autoclave (made by Nitto Koatsu) with an internal volume of 5.4 L, and the liquid temperature (internal temperature) ) Was kept at 50 ° C., and the autoclave was purged with nitrogen. The liquid temperature was continuously heated from about 145 ° C. until the pressure in the autoclave tank reached about 2.5 kg / cm ² as gauge pressure (hereinafter, all pressure in the tank was expressed as gauge pressure). . In order to keep the pressure in the tank at about 2.5 kg / cm ² , heating was continued while removing water out of the system, and the aqueous solution was concentrated to a concentration of about 85%. The removal of water was stopped, and heating was continued until the pressure in the tank reached about 30 kg / cm ² . In order to keep the pressure in the tank at 30 kg / cm ² , heating was continued until the temperature reached 300 ° C. while removing water out of the system. Further, while continuing the heating, the pressure in the tank was reduced from 30 kg / cm ² to atmospheric pressure (gauge pressure was 0 kg / cm ² ) over 120 minutes.

Thereafter, the heater temperature was adjusted so that the final temperature of the resin temperature (liquid temperature) in the tank was 350 ° C. The resin temperature was maintained at 350 ° C., and the inside of the tank was maintained under a reduced pressure of 1.33 × 10 ⁴ Pa (100 torr) for 10 minutes by a vacuum apparatus. Thereafter, the inside of the tank was pressurized with nitrogen, and the resin was discharged in a strand form from the lower nozzle (nozzle). Further, the strand-like resin was cooled with water and cut to discharge in a pellet form to obtain a PA-7 pellet. The obtained pellets were dried at 120 ° C. for 10 hours in a nitrogen stream. Here, the amino group terminal was 22 μmol / g, the carboxyl group terminal was 94 μmol / g, and the amino group terminal concentration / carboxyl group terminal concentration was 0.234. In addition, the measurement of each terminal group density | concentration was calculated | required by the titration method similar to the Example of Unexamined-Japanese-Patent No. 2003-119376 as mentioned above.

2. Carbodiimide compound As the carbodiimide compound, Nisshinbo Co., Ltd. trade name: Carbodilite (registered trademark) V-02 (an aqueous solution having a solid content of 40% by mass) was used.

3. Polyurethane resin emulsion The product name: Bondic (registered trademark) 1050: (an aqueous solution having a solid content of 50% by mass) manufactured by Dainippon Ink Co., Ltd. was used as the polyurethane resin emulsion.

4). Maleic anhydride copolymer As a maleic anhydride-butadiene copolymer aqueous solution, trade name: Acro Binder (registered trademark) BG-7 (an aqueous solution having a solid content of 25% by mass) manufactured by Sanyo Chemical Industries, Ltd. was used. .

5. Aminosilane coupling agent γ-aminopropyltriethoxysilane (trade name: KBE-903, manufactured by Shin-Etsu Chemical Co., Ltd.) was used.

6). Lubricant Brand name: Carnauba wax (manufactured by Yoko Kato) was used.

7). Lubricant Ethylene bis stearic acid amide (hereinafter abbreviated as “EBS”) (trade name: Kao Wax EB-P, manufactured by Kao Corporation) was used.

[Manufacture of glass fiber]
<Production Example 1>
First, it is diluted with water so that the solid content is 4% by mass of a carbodiimide compound, 2% by mass of a polyurethane resin, 0.6% by mass of γ-aminopropyltriethoxysilane, and 0.1% by mass of carnauba wax. A fiber sizing agent was obtained. The obtained glass fiber sizing agent was adhered to the glass fiber by an applicator provided in the middle of being wound around the rotating drum with respect to the melt-proofed glass fiber having an average diameter of 10 μm. And the roving of the glass fiber bundle surface-treated with the said glass fiber sizing agent was obtained by drying after that. At that time, the glass fiber was made to be a bundle of 1,000 pieces. The adhesion amount of the glass fiber sizing agent was 0.6% by mass. This was cut into a length of 3 mm to obtain a chopped strand (hereinafter abbreviated as “GF-1”).

<Production Example 2>
The solid content is 2% by weight of polyurethane resin, 4% by weight of maleic anhydride-butadiene copolymer, 0.6% by weight of γ-aminopropyltriethoxysilane, and 0.1% by weight of carnauba wax. Dilution was performed to obtain a glass fiber sizing agent. The obtained glass fiber sizing agent was adhered to the glass fiber by an applicator provided in the middle of being wound around the rotating drum with respect to the melt-proofed glass fiber having an average diameter of 10 μm. And the roving of the glass fiber bundle surface-treated with the said glass fiber sizing agent was obtained by drying after that. At that time, the glass fiber was made to be a bundle of 1,000 pieces. The adhesion amount of the glass fiber sizing agent was 0.6% by mass. This was cut into a length of 3 mm to obtain a chopped strand (hereinafter abbreviated as “GF-2”).

[Evaluation method]
Below, the evaluation method performed by the Example and the comparative example is demonstrated.

<Adhesion amount of glass fiber sizing agent>
After weighing 10 g of the glass fiber surface-treated with the glass fiber sizing agent, it was heated in an electric furnace at 650 ° C. for 1 hour. The amount of mass decrease during this period was defined as the amount of glass fiber sizing agent attached.

<Bending deflection amount>
Using the injection molding machine (PS-40E: made by Nissei Resin Co., Ltd.), the pellets of the polyamide resin compositions obtained in the examples and comparative examples were formed into multi-purpose test pieces A-type molded pieces in accordance with ISO 3167. Molded. At that time, injection and holding pressure time 25 seconds, cooling time 15 seconds, mold temperature 80 ° C (PA-1 to PA5) or 120 ° C (PA-6 to PA-7), molten resin temperature 290 ° C (PA- 1 to PA5) or 345 ° C. (PA-6 to PA-7). The obtained molded piece was cut and used, and a bending test was performed in accordance with ISO 178 using a test piece of thickness 80 mm × width 10 mm × length 4 mm, and the amount of deflection at the maximum load point was measured.

<Tensile strength at 80 ° C>
The above-mentioned multipurpose test piece (A type) was held at 80 ° C. for 2 hours, and in accordance with ISO 527, a tensile test was performed at a tensile speed of 5 mm / min to measure the tensile strength.

<Processability (Chip generation amount)>
1 kg of the polyamide resin composition pellets obtained in the examples and comparative examples were sieved for 1 minute using a 40-mesh sieve (opening: 0.425 mm), and the amount of falling chips was measured.

<Plasticization stability>
Using the injection molding machine (PS-40E: made by Nissei Resin Co., Ltd.), the pellets of the polyamide resin compositions obtained in the examples and comparative examples were formed into multi-purpose test pieces A-type molded pieces in accordance with ISO 3167. Molded. At that time, the injection and pressure holding time were set to 25 seconds, the cooling time was set to 15 seconds, the mold temperature was 80 ° C., and the molten resin temperature was 290 ° C. Molding was performed up to 50 shots, and the plasticization stability was determined from the difference (xy) between the maximum plasticization time (x seconds) and the minimum plasticization time (y seconds) between 10 shots and 50 shots. The smaller the difference between the maximum plasticization time and the minimum plasticization time, the better the plasticization stability.

[ Reference Example 1, Examples 2-4 , Comparative Examples 1-2]
L / D (extruder cylinder length / extruder cylinder diameter) having an upstream supply port in the first barrel from the upstream side of the extruder and a downstream supply port in the ninth barrel = 48 (number of barrels: 12) twin screw extruder (ZSK-26MC: manufactured by Coperion (Germany)) was used. In the twin-screw extruder, the distance from the upstream supply port to the die was set to 290 ° C., screw rotation speed 200 rpm, and discharge rate 20 kg / hour. Under such conditions, polyamide (PA-1 to PA-5) is supplied from the upstream supply port so as to have the ratio described in the upper part of Table 1 below, and glass fiber chopped strands (GF) are supplied from the downstream supply port. -1 to GF-2). And the pellet of the resin composition was manufactured by melt-kneading these. The obtained resin composition was molded at a resin temperature of 290 ° C. and a mold temperature of 80 ° C., and the bending deflection amount and the tensile strength were evaluated. In addition, the amount of chips generated was measured. These evaluation results are shown in Table 1 below.

From Table 1, when Reference Example 1 and Examples 2 to 4 are compared with Comparative Example 1, when the amino group terminal concentration / carboxyl terminal concentration of the polyamide resin is more than 0.63, 0.63 or less In comparison, it was confirmed that the amount of bending deflection and the tensile strength at 80 ° C. were significantly high, and the amount of chips generated was significantly small.

In addition, when Reference Example 1 and Comparative Example 2 are compared, when the sizing agent containing the polycarbodiimide compound is used, the bending deflection amount and the tensile strength at 80 ° C. are compared with the case of using the sizing agent not containing the polycarbodiimide compound. It was confirmed that the strength was significantly high and the amount of chips generated was significantly small.

[Examples 5 and 6, Comparative Examples 3 and 4]
L / D (extruder cylinder length / extruder cylinder diameter) having an upstream supply port in the first barrel from the upstream side of the extruder and a downstream supply port in the ninth barrel = 48 (number of barrels: 12) twin screw extruder (ZSK-26MC: manufactured by Coperion (Germany)) was used. In the twin-screw extruder, the distance from the upstream supply port to the die was set to 290 ° C., screw rotation speed 200 rpm, and discharge rate 20 kg / hour. Under such conditions, polyamide (PA-2) and lubricant (EBS) are supplied from the upstream supply port so that the ratio described in the upper part of Table 2 below is obtained, and glass fiber chopped strands (from the downstream supply port) GF-1 to GF-2) were supplied. And the pellet of the resin composition was manufactured by melt-kneading these. The obtained resin composition was molded at a resin temperature of 290 ° C. and a mold temperature of 80 ° C., and the bending deflection amount and the tensile strength were evaluated. In addition, the amount of chips generated was measured. Furthermore, plasticization stability was evaluated. These evaluation results are shown in Table 2 below.

  From Table 2, when Example 5 and Comparative Example 3 and Example 6 and Comparative Example 4 are respectively compared, when a sizing agent containing a polycarbodiimide compound is used, a sizing agent not containing a polycarbodiimide compound is used. As compared with the above, it was confirmed that the bending deflection amount and the tensile strength at 80 ° C. were significantly high, and the amount of chips generated was significantly small. Moreover, in the case containing a lubricant, it was confirmed that the plasticization stability during molding was also excellent.

[Examples 7 and 8, Comparative Examples 5 and 6]
L / D (extruder cylinder length / extruder cylinder diameter) having an upstream supply port in the first barrel from the upstream side of the extruder and a downstream supply port in the ninth barrel = 48 (number of barrels: 12) twin screw extruder (ZSK-26MC: manufactured by Coperion (Germany)) was used. In the twin-screw extruder, the distance from the upstream supply port to the die was set to 340 ° C., the screw rotation speed 250 rpm, and the discharge amount 25 kg / hour. Under such conditions, polyamide (PA-6 to PA-7) is supplied from the upstream supply port so that the ratio described in the upper part of Table 3 below is obtained, and glass fiber chopped strands (GF) are supplied from the downstream supply port. -1 to GF-2). And the pellet of the resin composition was manufactured by melt-kneading these. The obtained resin composition was molded at a resin temperature of 345 ° C. and a mold temperature of 120 ° C., and the bending deflection amount and the tensile strength were evaluated. In addition, the amount of chips generated was measured. These evaluation results are shown in Table 3 below.

  From Table 3, when Example 7 and Comparative Example 5 and Example 8 and Comparative Example 6 are respectively compared, when a sizing agent containing a polycarbodiimide compound is used, a sizing agent not containing a polycarbodiimide compound is used. As compared with the above, it was confirmed that the bending deflection amount and the tensile strength at 80 ° C. were significantly high, and the amount of chips generated was significantly small.

  From the above, by adopting the present embodiment, the mechanical strength, toughness (bending deflection), heat resistance and workability can be remarkably improved particularly at high temperatures, such as automobile parts and various electronic parts. It can be seen that can be applied sufficiently.

  Since the resin composition according to the present invention is excellent in mechanical strength, toughness, heat resistance and processability at high temperatures, it can be suitably used as a molded product requiring high mechanical properties such as automobile parts.

Claims (4)

A glass fiber reinforced polyamide resin composition comprising (A) a polyamide resin and (B) a glass fiber containing a glass fiber sizing agent containing a polycarbodiimide compound,
The glass fiber sizing agent is a polyurethane resin, a homopolymer of acrylic acid, a copolymer of acrylic acid and other copolymerizable monomers, a salt of a polymer of acrylic acid with a primary, secondary or tertiary amine, and And further comprising at least one selected from the group consisting of copolymers comprising a carboxylic acid anhydride-containing unsaturated vinyl monomer and other unsaturated vinyl monomers,
In the component (A), a glass fiber reinforced polyamide resin composition having a ratio of amino group terminal concentration to carboxyl group terminal concentration of 0.65 or more .   The glass fiber reinforced polyamide resin composition according to claim 1, wherein the glass fiber sizing agent comprises a polycarbodiimide compound and a polyurethane resin.   The glass fiber-reinforced polyamide resin composition according to claim 1 or 2, wherein a carboxyl group terminal concentration of the component (A) is 50 µmol / g or more.   The glass fiber reinforced polyamide resin composition according to any one of claims 1 to 3, wherein the component (B) is 1 to 200 parts by mass with respect to 100 parts by mass of the component (A).