JP3385096B2 - Reinforced polyamide resin connector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced polyamide resin connector having less warpage and excellent mechanical strength, toughness, heat resistance and dimensional stability. Due to its excellent characteristics, the connector of the present invention can be widely used mainly in the fields of electric and electronic devices and automobiles.

[0002]

2. Description of the Related Art In the fields of electric and electronic equipment and automobiles, nylon 6, nylon 66, polybutylene terephthalate (P
BT), polyphenylene sulfide (PPS), etc. are used. These thermoplastic resins are easy to mold and the demand for them has been increasing in recent years. However, various problems have been pointed out in the performance of connectors made of these resins.

For example, a connector made of nylon 6 or nylon 66 has excellent chemical resistance and abrasion resistance,
It has been a problem that dimensional changes due to water absorption and mechanical strength decrease are large. Further, for the purpose of improving heat resistance and mechanical strength, it has been carried out to mix an inorganic reinforcing material such as glass fiber, but in this case, there is a new problem that the warpage of the molded connector becomes large. It may occur.

Although the PBT connector has little dimensional change and mechanical strength reduction due to water absorption as seen in polyamide resins such as nylon 6 and nylon 66, it has insufficient heat resistance and chemical resistance. In order to improve heat resistance, an inorganic reinforcing material such as glass fiber has been blended, but even in this case, there is a problem that the warpage of the molded product becomes large.

PPS has low crystallinity, and it is generally formed by mixing an inorganic reinforcing material such as glass fiber.
Also in this case, there is a problem that the warp of the molded product becomes large. Further, since PPS has poor resin fluidity and is inferior in toughness and abrasion resistance, there is a problem that a molded product becomes brittle, and its use range is limited.

Thus, there is little warpage, mechanical strength,
A connector made of a thermoplastic resin excellent in toughness, heat resistance and dimensional stability is required in industrial fields such as electric and electronic devices and automobiles, but none of them satisfies these performances.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and provides a connector having less warpage and excellent mechanical strength, toughness, heat resistance and dimensional stability. is there.

[0008]

Means for Solving the Problems As a result of intensive studies to solve such problems, the present inventors have formed a reinforced polyamide resin composition containing a polyamide and a specific fluoromica-based mineral. It was found that the connector obtained by doing so can solve the problems of the present invention, and arrived at the present invention.

That is, the gist of the present invention is as follows. A reinforced polyamide resin connector composed of a composition comprising 100 parts by weight of polyamide and 0.01 to 100 parts by weight of a swelling fluoromica-based mineral.

The polyamide used in the present invention means a polymer having an amide bond formed from an amino acid, a lactam or a diamine and a dicarboxylic acid. Examples of the monomer that forms such a polyamide include the following. Examples of amino acids include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and para-aminomethylbenzoic acid.

As the lactam, ε-caprolactam, ω
-Laurolactam, etc. Examples of diamines are tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2.
4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 2,4-dimethyloctamethylenediamine, metaxylylenediamine,
Paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-
3,5,5-Trimethylcyclohexane, 3,8-bis (aminomethyl) tricyclodecane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis ( 4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine and the like.

Examples of the dicarboxylic acid include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2
-Chloroterephthalic acid, 2-methylterephthalic acid, 5-
Examples include methyl isophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid and diglycolic acid.

Polyamides used in the present invention are preferably polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide. (Nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecamethylene adipamide (nylon 116), polyundecane amide (nylon 11), polydodecane amide (nylon 12), polytrimethylhexamethylene terephthalamide ( Nylon TMDT), polyhexamethylene terephthalamide (nylon 6T), polyhexamethylene isophthalamide (nylon 6I), polybis (4-aminocyclohexyl) methandodecamide, (nylon PACM
12), polybis (3-methyl-4-aminocyclohexyl) methandodecamide (nylon dimethyl PACM1)
2), polymeta-xylylene adipamide (nylon MXD
6), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylene hexahydroterephthalamide (nylon 11T (H)), and copolyamides and mixed polyamides thereof. Of these, nylon 6, nylon 46, and nylon 6 are particularly preferable.
6, Nylon 12, copolyamides of these, and mixed polyamides.

The polyamide used here is manufactured by a known melt polymerization method, or in combination with a solid phase polymerization method. The relative viscosity of the polyamide used in the present invention is not particularly limited, but phenol / tetrachloroethane = 60/40 (weight ratio) is used as a solvent, and the temperature is 25.
The relative viscosity determined under the conditions of ° C and a concentration of 1 g / dl is preferably in the range of 1.5 to 5.0. Relative viscosity is 1.
If it is less than 5, the mechanical performance of the resin composition deteriorates, which is not preferable. On the other hand, when it exceeds 5.0, the moldability of the resin composition rapidly decreases, which is not preferable.

The swellable fluoromica-based mineral used in the present invention is obtained by heat-treating a mixture of talc and sodium and / or lithium silicofluoride or fluoride. As a specific method, there is a method disclosed in Japanese Patent Laid-Open No. 2-149415. That is, it is a method in which talc is used as a starting material and sodium ions and / or lithium ions are intercalated into the starting material to obtain a swellable fluoromica-based mineral. In this method, a fluoric mica-based mineral is obtained by mixing talc with silicofluoride and / or fluoride and heat-treating in a magnetic crucible at about 700 to 1200 ° C. for a short time. The swellable fluoromica-based mineral used in the present invention is particularly preferably one produced by this method.

In order to obtain a swelling fluoromica-based mineral, it is necessary that the metal constituting the silicofluoride or fluoride is sodium or lithium among the alkali metals. These alkali metals may be used alone or in combination. Of the alkali metals, potassium is not preferable because it does not give a swelling fluoromica-based mineral, but it is used in combination with sodium or lithium, and if it is a limited amount, it is used for the purpose of adjusting the swelling property. Is also possible. The amount of silicofluoride and / or fluoride mixed with talc is 10% of the total mixture.
It is preferably in the range of up to 35% by weight, and if it is out of this range, the production rate of the swellable fluoromica-based mineral will be reduced.

The swellable fluoromica-based mineral produced by the above method has a structure represented by the following formula (1) as a general formula. α (MF) · β (aMgF ₂ · bMgO) · γSiO ₂ (1) (where M represents sodium or lithium, α,
β, γ, a and b each represent a coefficient, and 0.1 ≦ α ≦
2, 2 ≦ β ≦ 3.5, 3 ≦ γ ≦ 4, 0 ≦ a ≦ 1, 0 ≦ b
≦ 1, a + b = 1. )

The term "swelling property" as used in the present invention means that the fluoromica-based mineral absorbs polar molecules such as amino acids, nylon salts and water molecules or cations between the layers to increase the interlayer distance or further swelling and cleavage. The characteristic is that the particles become ultrafine particles. The fluoromica-based mineral represented by the formula (1) exhibits such swelling property. The preferred size of the swellable fluoromica-based mineral used in the present invention has an average particle size of 10 μm or less. The swelling fluoromica-based mineral used in the present invention has a layer thickness in the C-axis direction of 9 to 20 as measured by an X-ray powder method.
It is Å.

In the step of producing the swellable fluoromica-based mineral used in the present invention, alumina (Al ₂ O ₃ )
It is also possible to adjust the swelling property of the resulting swelling fluoromica-based mineral by blending a small amount of.

The amount of the swellable fluoromica-based mineral compounded is 0.01 to 100 parts by weight, preferably 0.1 to 2 parts by weight based on 100 parts by weight of the polyamide or the amount of the monomers forming the polyamide.
0 parts by weight. If it is less than 0.01 part by weight, the effect of improving the mechanical strength, heat resistance, and dimensional stability that is the object of the present invention cannot be obtained, and if it exceeds 100 parts by weight, the toughness is greatly reduced, which is not preferable.

As a method for producing the reinforced polyamide resin composition of the present invention, there is a method in which a polyamide and a swelling fluoromica-based mineral are melt-kneaded using a general extruder. 2 for better dispersion
Preference is given to using a screw extruder.

The most preferred method for producing the reinforced polyamide resin composition of the present invention is to strengthen the polyamide by polymerizing the monomer in the presence of a predetermined amount of the swelling fluoromica mineral with respect to the monomer forming the polyamide. It is a method of obtaining a resin composition. In this case, the swellable fluoromica-based mineral is sufficiently finely dispersed in the polyamide, and the effect of the present invention is most remarkable. in this case,
The swelling fluoromica-based mineral used in the present invention does not need to be subjected to a swelling treatment in advance, and may be mixed with a monomer in a predetermined amount and polymerized.

The reinforced polyamide resin composition of the present invention contains a pigment, a heat stabilizer, an antioxidant, a weathering agent, a flame retardant, a plasticizer, a release agent, and other reinforcing materials as long as the characteristics thereof are not significantly impaired. It is also possible to add. As the heat stabilizer and antioxidant, for example, hindered phenols, phosphorus compounds, hindered amines, sulfur compounds, copper compounds, alkali metal halides or a mixture thereof can be used. In particular, copper compounds and alkali metal halides are most effective. Additives such as these heat stabilizers, antioxidants and weathering agents are generally added during melt kneading or polymerization. Examples of the reinforcing material include clay, talc, calcium carbonate, zinc carbonate, wollastonite, silica, alumina, magnesium oxide, calcium silicate, asbestos, sodium aluminate, calcium aluminate, sodium aluminosilicate, magnesium silicate, glass balloon. , Carbon black, zinc oxide, antimony trioxide, zeolite, hydrotalcide, metal fibers, metal whiskers, ceramic whiskers, potassium titanate, boron nitride, graphite, glass fibers, carbon fibers and the like.

Further, if necessary, other polymers can be added to the resin composition of the present invention. Examples of such a polymer include polybutadiene, butadiene-styrene copolymer, acrylic rubber, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, natural rubber, chlorinated butyl rubber, chlorinated polyethylene and other elastomers, and Acid-modified products of these with maleic anhydride, styrene-maleic anhydride copolymer, styrene-phenylmaleimide copolymer, polyethylene, polypropylene, butadiene-acrylonitrile copolymer, polyvinyl chloride, polyethylene terephthalate, P
Examples include BT, polyacetal, polyvinylidene fluoride, polysulfone, PPS, polyether sulfone, phenoxy resin, polyphenylene ether, polymethyl methacrylate, polyether ketone, polyarylate, polycarbonate, and polytetrafluoroethylene.

The connector of the present invention can be obtained by molding by a general injection molding method using a general injection molding machine having a screw type thermoplasticization mechanism. Since the reinforced polyamide resin composition of the present invention has an extremely high crystallization rate as compared with the polyamide resin alone, a connector having a complicated shape can be molded in a short molding cycle without releasing trouble.

Further, since the connector of the present invention is superior in toughness as compared with the connector obtained by molding glass fiber reinforced polyamide resin, there is less problem such as cracking when attaching or detaching the connector to or from electric parts. Has the advantage.

[0027]

EXAMPLES Next, the present invention will be described more specifically by way of examples. The raw materials and measuring methods used for the evaluation of Examples and Comparative Examples are as follows. (1) For talc pulverized with a raw material swelling fluoromica-based mineral ball mill to have an average particle size of 2 μm, the total amount of silicofluoride, fluoride or alumina shown in Table 1 having the same average particle size of 2 μm is used. Of 20% by weight, and the mixture was placed in a magnetic crucible and kept at 800 ° C. for 1 hour in an electric furnace to synthesize M-1 to M-3 fluoromica minerals. The average particle diameter of the produced fluoromica-based mineral was 1.8 μm. In addition, as a result of measurement by the X-ray powder method, in M-1 to M-3, the peak corresponding to the thickness 9.2Å of the raw material talc in the C-axis direction disappeared, and the formation of swellable fluoromica-based minerals. Peaks corresponding to 12 to 16Å shown were recognized.

[0028]

[Table 1]

(2) Measuring method 1. Amount of compounded material The amount of the swellable fluoromica-based mineral compounded in the polyamide resin composition was determined from the residue of baked pellets at 600 ° C. (Wt%) 2. Measurements were made according to ASTM D638 using a tensile strength test piece. 3. The flexural modulus test piece was used to perform the measurement based on ASTM D790. 4. Heat Deflection Temperature (HDT) Measurements were made according to ASTM D648 using test pieces. The load was 18.6 kg / cm ² . 5. Moisture-absorption molded connector, 2 at the condition of 60 ℃, 95% RH
It was treated for 4 hours. 6. Moisture absorption rate It was calculated from the weight change of the molded connector after the moisture absorption treatment. 7. Dimensional change The dimensional change of L ₀ in FIG. 1 after the moisture absorption treatment of the molded connector was measured. 8. The sled moisture-absorbing connector was placed on a horizontal plate, and the gap d between the central portion of the connector and the horizontal plate shown in FIG. 3 was taken as the amount of sled.

Examples 1-3: 10 kg of ε-caprolactam, 2 kg of water and M
-1, M-2 or M-3 is blended with 200 g each,
This was placed in a reactor having an internal volume of 30 liters and ε-caprolactam was polymerized in the presence of a swelling fluoromica-based mineral to obtain a reinforced nylon 6 resin composition. The polymerization reaction was performed as follows. That is, it is heated to 250 ° C. with stirring, and while gradually releasing steam, 4 kg / cm ² to 1
The pressure was raised to a pressure of 5 kg / cm ² . Then 2 kg /
The pressure was released to a pressure of cm ² , and polymerization was carried out at 260 ° C for 3 hours.
When the polymerization was completed, the reinforced nylon 6 resin composition was discharged from the reactor and cut into pellets. The obtained pellets of the reinforced nylon 6 resin composition were treated with hot water at 95 ° C., scoured, dried and then used to mold a test piece. The obtained pellets are respectively A-1, A-2, A-
Set to 3. The relative viscosities of A-1, A-2, and A-3 were 2.60, 2.61, and 2.60, respectively. Molding of the test piece and connector is done by using each mold.
It was performed using an injection molding machine J100S manufactured by Nippon Steel Co., Ltd. The cylinder temperature during molding was 260 ° C., and the mold temperature was 80 ° C. Various performance evaluations were performed using the obtained test pieces and connectors. The results are shown in Table 2.
Listed in.

Examples 4 to 5 Pellets of a reinforced nylon 6 resin composition were obtained in the same manner as in Examples 1 to 3 except that 400 g of M-1 or M-2 was blended. The obtained pellets were labeled A-4 and A, respectively.
-5. The relative viscosities of A-4 and A-5 are both 2.57.
Met. Performance evaluation is performed in the same manner as in Examples 1 to 3,
The results are listed in Table 2.

[0032]

[Table 2]

Examples 6 to 8 To 10 kg of nylon 66 salt, 3 kg of water and M-
150 g of each of M-1, M-2 or M-3 was blended and placed in a reactor having an internal volume of 30 liters, and a nylon 66 salt was polymerized in the presence of a swelling fluoromica-based mineral to obtain a reinforced nylon 66. A resin composition was obtained. The polymerization reaction was performed as follows. That is, the mixture was heated at 230 ° C. with stirring until the internal pressure became 18 kg / cm ² . After reaching that pressure, the pressure was maintained by heating while gradually releasing steam. When it reaches 280 ° C, the pressure is released to normal pressure,
Polymerization was further performed for 2 hours. When the polymerization was completed, the reinforced nylon 66 resin composition was discharged and cut into pellets. The pellet was dried and used for the test. The obtained pellets are designated as A-6, A-7 and A-8, respectively. The relative viscosities of A-6, A-7, and A-8 are 2.
It was 70, 2.71, 2.70. Test pieces and connectors were molded using these reinforced nylon 66 resin compositions. Molding was performed using each mold using an injection molding machine J100S manufactured by Nippon Steel Co., Ltd. Cylinder temperature during molding is 280 ℃ and mold temperature is 9
Performed at 0 ° C. Various performance evaluations were performed using the obtained test pieces and connectors. The results are listed in Table 3.

[0034]

[Table 3]

Examples 9 to 10 Pellets of a reinforced nylon 66 resin composition were obtained in the same manner as in Examples 6 to 8 except that 300 g each of M-1 or M-2 was blended. The obtained pellets were A-9,
A-10. The relative viscosities of A-9 and A-10 were 2.67 and 2.68, respectively. The performance evaluation was performed in the same manner as in Examples 6 to 8 below. The results are listed in Table 3.

Comparative Examples 1 and 2 Commercially available non-reinforced nylon 6 resin (A103, manufactured by Unitika Ltd.)
0BRL) and glass fiber reinforced nylon 6 resin (A1030GFL20, manufactured by Unitika Ltd., compounded with 20% by weight of glass fiber) were used to mold test pieces and connectors under the same molding conditions as in Examples 1 to 5. Various performance evaluations were performed using the obtained test pieces and connectors. The results are listed in Table 4.

Comparative Examples 3 and 4 Commercially available unreinforced nylon 66 resin (IC10, A10)
0) and glass fiber reinforced nylon 66 resin (manufactured by ICI,
Using A190 and 33% by weight of glass fiber), a test piece and a connector were molded under the same molding conditions as in Examples 6 to 10. Various performance evaluations were performed using the obtained test pieces and connectors. The results are shown in Table 4.
Listed in.

[0038]

[Table 4]

[0039]

According to the present invention, a connector having less warpage and excellent mechanical strength, toughness, heat resistance and dimensional stability can be obtained.

[Brief description of drawings]

FIG. 1 shows a plan view of an example of a connector of the present invention.

FIG. 2A is a side view of an example of the connector of the present invention,
(B) shows a side view of the connector after warpage occurs.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Izumi Yoshida 23, Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Laboratory (56) Reference JP-A-6-80820 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 77/00-77/12

Claims (4)

(57) [Claims] 1. A reinforced polyamide resin connector composed of a composition comprising 100 parts by weight of polyamide and 0.01 to 100 parts by weight of a swelling fluoromica-based mineral. 2. The swellable fluoromica-based mineral is obtained by heating a mixture of talc and sodium and / or lithium silicofluoride or fluoride.
The listed connector. 3. The polyamide is polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 6).
6), polytetramethylene adipamide (nylon 4
The connector according to claim 1, which is one or more of 6), polydodecanamide (nylon 12), or a copolymer thereof. 4. A swelling fluoromica-based mineral is added in an amount of 0.01 to 1 with respect to the amount of monomers forming 100 parts by weight of polyamide.
A reinforced polyamide resin connector composed of a composition obtained by polymerizing a monomer in the presence of 100 parts by weight.