JP3150733B2 - Resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition, and more particularly to a polytetramethylene adipamide (nylon 46) exhibiting excellent heat resistance, mechanical properties, impact properties and oil resistance.
About resin.

[0002]

2. Description of the Related Art A nylon 46 resin obtained from tetramethylenediamine or a functional derivative thereof and adipic acid or a functional derivative thereof is known.

[0003] This nylon 46 resin is considered to have great utility value as a useful engineering plastic because it is excellent in heat resistance, mechanical properties such as tensile strength and bending strength, and sliding properties.

In particular, in the field of automobile parts and mechanical parts, while plastics are being pursued for the purpose of weight reduction, labor saving, low noise, etc., demands for heat resistance thereof have been increasing in recent years. Expectations for nylon 46 resin are great.

However, when used in these fields, there are many opportunities for the parts to come into contact with various oils and greases.

At room temperature, the contact between the resin and the oils hardly poses a problem. However, in many applications where the heat resistance of the nylon 46 resin is utilized, for example, when the resin comes into contact with oil or grease at a high temperature of 100 ° C. or higher. Although it is due to the action of various additives in these oils and greases, the degradation of the nylon 46 resin is promoted, and the deterioration of its mechanical properties becomes very large.

Reinforcing the nylon 46 resin with a fibrous reinforcing material such as glass fiber is effective not only in improving strength but also in improving oil resistance at high temperatures.

However, in applications where the toughness such as impact strength of nylon 46 resin must be utilized, when reinforced with a fibrous reinforcing material such as glass fiber, there is a problem that its characteristics are lost. Improvements in toughness and impact strength when reinforced with a reinforcing material are desired.

[0009]

An object of the present invention is to provide a nylon 46 resin composition having improved oil resistance and exhibiting well-balanced mechanical properties such as heat resistance and toughness. .

[0010]

The present inventors have conducted intensive studies to improve the oil resistance of nylon 46 resin. As a result, a carboxylic acid or a derivative thereof was added to a nylon 46 resin reinforced with a fibrous reinforcing material such as glass fiber to form a molecular chain. The present inventors have found that a composition containing a specific amount of the olefin copolymer contained therein meets the above-mentioned object, and reached the present invention.

That is, the resin composition of the present invention comprises (A)
Per 100 parts by weight of nylon 46 resin, (B) 3 to 40 parts by weight of an olefin copolymer containing a carboxylic acid or a derivative thereof in a molecular chain, and (C) 3 to 100 parts of a fibrous reinforcing material
It is a resin composition containing parts by weight.

The present invention will be described.

The nylon 46 resin as the component (A) used in the present invention is a polyamide obtained by a condensation reaction using adipic acid or a functional derivative thereof as an acid component and tetramethylene diamine or a functional derivative thereof as an amine component. However, the adipic acid component or the tetramethylenediamine component may be partially replaced by another copolymerization component.

Preferred embodiments of the nylon 46 resin are described in JP-A-56-149430 and JP-A-56-1494.
No. 31 is described.

The intrinsic viscosity of the nylon 46 resin used in the present invention, when measured at 35 ° C. using m-cresol, is in the range of 0.90 to 1.90, and more preferably 1.00 to 1.50. Is desirable.

Nylon 46 with intrinsic viscosity exceeding 1.90
When a resin is used, the fluidity of the composition in a molten state is poor, and not only is the gloss of the appearance of the obtained molded article lost, but also the dispersion of its mechanical properties and thermal properties is unfavorably large.

On the other hand, when the intrinsic viscosity is lower than 0.90, there is a disadvantage that the mechanical strength of the composition is reduced.

The olefin copolymer containing the carboxylic acid or the derivative thereof as the component (B) in the molecular chain used in the present invention includes ethylene and α-olefins having 3 to 20 carbon atoms and dienes such as propylene. 1-butene, 1
-Pentene, 4-methyl-1-pentene, 1,4-hexadiene, dicyclopentadiene, 2,5-norbornadiene, 5-ethyl-2,6-norbornadiene, 5-
Ethylidene norbornene, 5- (1'-propenyl)-
2-norbornene, butadiene, isoprene, or the like as a main component, and a carboxylic acid group or a derivative thereof such as at least one selected from carboxylic acid metal bases, carboxylic acid ester groups, acid anhydride groups, and acid amide groups. It refers to a copolymer into which a monomer component having a certain functional group is introduced.

Examples of the monomer having this functional group include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, methylmaleic acid, methylfumaric acid, mesaconic acid, citraconic acid, glutaconic acid and acrylic acid. Methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl methacrylate, aminoethyl methacrylate, dimethyl maleate, Dimethyl itaconate, sodium methacrylate, potassium methacrylate, magnesium methacrylate, zinc acrylate, maleic anhydride, itaconic anhydride, citraconic anhydride, glycidyl acrylate, glycidyl methacrylate, vinyl glycidyl Ether, vinyl acetate, alpha of acrylamide, such as β- unsaturated carboxylic acid derivatives.

Methods for introducing these functional group-containing monomer components include copolymerization with ethylene and α-olefin, and grafting to polyolefin.

The amount of the monomer component having a functional group to be introduced is 0.001 to 10 mol%, preferably 0.01 to 5 mol%, based on all components. This introduction amount is 0.001
When the amount is less than 10 mol%, the compatibility with the nylon 46 resin is not sufficient, and when the amount is 10 mol% or more, the stability of the polyolefin is lowered and a side reaction such as gelation is apt to occur.

Preferred examples of the olefin copolymer containing a carboxylic acid or a derivative thereof in the molecular chain used in the present invention include ethylene-acrylic acid copolymer and ethylene-methacrylic acid-sodium methacrylate. Copolymer, ethylene-methacrylic acid-zinc methacrylate copolymer, ethylene-methacrylic acid-magnesium methacrylate copolymer, ethylene-isobutyl acrylate-methacrylic acid-zinc methacrylate copolymer, Ethylene-methyl acrylate copolymer, ethylene-methyl acrylate-acrylic acid copolymer, ethylene
Ethyl acrylate copolymer, ethylene-glycidyl methacrylate copolymer, ethylene-vinyl acetate-glycidyl methacrylate copolymer, polyethylene-maleic anhydride copolymer, polypropylene-maleic anhydride copolymer, poly ( Ethylene / propylene) -maleic anhydride copolymer, poly (ethylene / butadiene) -maleic anhydride copolymer, poly (ethylene / propylene / 1,4-hexadiene) -maleic anhydride copolymer, poly (ethylene / Examples thereof include propylene / dicyclopentadiene) -maleic anhydride copolymer, poly (ethylene / propylene / 5-ethylidene norbornene) -maleic anhydride copolymer, and polyisoprene-maleic anhydride copolymer.

Further, these copolymers of the component (B) may be PQP type or PQP 'type block copolymers including the above-mentioned copolymers.

Examples of the fibrous reinforcing material of the component (C) used in the present invention include glass fiber, aramid fiber, carbon fiber, steel fiber, ceramic fiber, potassium titanate whisker, boron whisker and the like. A combination of more than one species can also be used.

Among these fibrous reinforcing materials, reinforcement by glass fiber is preferable, and the glass fiber is not particularly limited as long as it is generally used for reinforcing resin. For example, it can be used by selecting from long fiber type (glass roving), short fiber chopped strand, milled fiber and the like.

The fibrous reinforcing material such as glass fiber is treated with a sizing agent (eg, polyvinyl acetate, polyester sizing agent, etc.), a coupling agent (eg, silane compound, borane compound, titanium compound, etc.), and other surface treatment agents. It may be.

Usually, a long fiber type glass fiber is used after being cut into a desired length before or after blending with a resin, and this mode of use is also useful in the present invention.

The amount of the fibrous reinforcing material is preferably 3 to 100 parts by weight based on 100 parts by weight of the nylon 46 resin.
When the amount is less than 3 parts by weight, the effect of improving the heat resistance such as the mechanical strength and oil resistance of the molded product is not sufficient,
A satisfactory molded product cannot be obtained. On the other hand, if it exceeds 100 parts by weight, it is difficult to obtain a molded article having a good appearance because the fluidity of the composition in a molten state is remarkably inferior, and it also reaches saturation in strength. Absent.

When a glass fiber is used, a glass fiber having a length of 0.2 mm or more at the main part in the composition is preferably used.

When the nylon 46 resin is reinforced with this fibrous reinforcing material such as glass fiber, not only the mechanical strength but also the oil resistance of the nylon 46 resin at high temperatures is greatly improved, while the composition has a toughness such as impact strength. It also has the drawback of being inferior.

However, when the composition is further blended with an olefin copolymer containing a carboxylic acid or a derivative thereof in the molecular chain, it has been found that the effect of improving the toughness such as impact strength can be achieved without lowering the oil resistance. Was.

Olefin copolymers containing a carboxylic acid or a derivative thereof in the molecular chain may improve toughness such as impact strength when mixed alone with nylon 46 resin. It can be easily inferred that the same effect is exhibited when reinforced with the fibrous reinforcing material described above.

However, by blending this copolymer, which is less heat-resistant than nylon 46 resin itself, into nylon 46 resin, the effect of improving the oil resistance without deterioration is exhibited.

When a reinforcing material such as glass fiber is not contained, the oil resistance of the olefinic copolymer containing the carboxylic acid or a derivative thereof in the nylon 46 resin is hardly improved even if the olefinic copolymer containing the carboxylic acid or the derivative thereof in the molecular chain is blended in the nylon 46 resin.

Therefore, these effects in the present invention are:
It is completely unpredictable from each constitutional unit, and appears only when they are combined.

As a result, a nylon 46 resin composition having a good balance of mechanical properties, toughness, and oil resistance can be obtained, and the properties can be further improved while maintaining the characteristics of the nylon 46 resin.

The amount of the olefin copolymer containing the carboxylic acid or its derivative in the molecular chain relative to the nylon 46 resin is 3 parts per 100 parts by weight of the nylon 46 resin.
４０40 parts by weight.

When the amount is less than 3 parts by weight, the desired effect of improving toughness is not obtained. When the amount is more than 40 parts by weight, heat resistance such as deflection temperature under load is reduced, and the characteristics of nylon 46 resin are reduced. Will be lost.

In the present invention, a composition comprising (A) to (C) and hydrotalcite as a component (D) is also preferable, in which case the oil resistance of the composition is further improved. can get.

The hydrotalcite of the component (D) used in the present invention has the following general formula (Formula 1)

[0041]

## STR1 ## M _1-x M ′ _x (OH) ₂ R _{x / n} · mH ₂ O

Wherein M is Mg,
M 'is selected from the group consisting of Al, Fe, Cr, Co, and In from the group consisting of Mn, Fe, Co, Ni, Cu, and Zn, and R is OH, F, Cl, Br, N
O ₃ , CO ₃ , SO ₄ , Fe (CN) ₆ and CH ₃ CO
O is selected from the group consisting of Also, m is a positive number,
x is a number in the range of 0 <x ≦ 0.5, and n is the same number as the valence of the anion of R.

The hydrotalcite includes both natural compounds and synthetic compounds, and both can be used in the present invention.

To the resin composition of the present invention, a pigment or other compounding agent may be added if necessary. Such ingredients include fillers such as kaolin, clay,
Wollastonite, talc, mica, calcium carbonate,
Examples include powdery, granular or plate-like inorganic fillers such as barium sulfate, glass beads, and glass flakes. These fillers are usually compounded as a reinforcing material, a surface modifier, or for the purpose of improving electrical and thermal properties, etc. It should be blended within a range that does not lose excellent properties and molding advantages.

Also, flame retardants such as brominated polystyrene,
Brominated polyphenylene ether, brominated epoxy, brominated bisphenol-A-diglycidyl ether and its oligomers, polycarbonate oligomer produced from brominated bisphenol-A, brominated biphenyl ether, brominated diphthalimide compound, chlorinated hexa Halogen-containing compounds such as pentadiene dimer; phosphorus compounds such as red phosphorus and triphenyl phosphate; phosphorus-nitrogen compounds such as phosphonamide; triazine compounds such as methamine, melam, melem, melon, cyanuric acid, and melamine cyanurate. A metal hydroxide such as aluminum hydroxide, magnesium hydroxide, dawsonite, or dihydrated hydrate or a flame retardant auxiliary used alone or in combination with the halogen-containing compound, for example, an antimony compound such as antimony trioxide; Boron, it is possible to blend the metal oxides such as iron oxide.

Further, for the purpose of improving heat resistance, an antioxidant or a heat stabilizer such as a copper compound such as copper iodide, a hindered phenol compound, an aromatic amine compound, an organic phosphorus compound or a sulfur compound can be added. . Various epoxy compounds, oxazoline compounds and the like may be added for the purpose of improving the melt viscosity stability and hydrolysis resistance. As the epoxy compound, for example, bisphenol-
Bisphenol-A type epoxy compound obtained by reacting A with epichlorohydrin, aliphatic glycidyl ether obtained from reaction of various glycols and glycerol with epichlorohydrin, novolak type epoxy compound,
Aromatic or aliphatic carboxylic acid type epoxy compounds, alicyclic compound type epoxy compounds and the like are preferable, and as the oxazoline compound, aromatic or aliphatic bisoxazoline,
In particular, 2,2'-bis (2-oxazoline), 2,2'-
m-Phenylenebis (2-oxazoline) is preferred.

Other stabilizers, coloring agents, lubricants, ultraviolet absorbers and antistatic agents can also be added.

Further, a small amount of other thermoplastic resins, such as other polyamide resins, polyester resins, polyphenylene sulfide resins, polyphenylene ether resins, polycarbonate resins, phenoxy resins, polyamide elastomers, polyester elastomers, etc .; For example, a phenol resin, a melamine resin, an unsaturated polyester resin, a silicone resin, or the like may be blended.

To obtain the resin composition of the present invention, any mixing method can be used.

Usually, it is preferable to disperse these components more uniformly. A method of mixing all or a part of the components simultaneously or separately with a mixer such as a blender, kneader, roll, extruder, or the like, A method in which a part of the mixing portion is mixed simultaneously or separately with a blender, kneader, roll, extruder or the like, and the remaining components are mixed and homogenized with the mixer or extruder can be used. Furthermore, there is a method in which a composition that has been dry-blended in advance is melt-kneaded with a heated extruder, homogenized, extruded into a wire, and then cut into a desired length to granulate. The molding composition thus produced is usually kept in a sufficiently dried state, charged into a molding machine hopper and subjected to molding. Furthermore, it is also possible to dry blend the constituent materials of the composition, directly charge them into a molding machine hopper, and melt-knead them in a molding machine.

[0051]

The present invention will be described in detail with reference to the following examples. In addition,
Various properties in the examples were measured by the following methods.

(1) Mechanical strength: The tensile test was performed using ASTM.
D638, impact test conforms to ASTM D256 (Izod, with notch) respectively.

(2) Deflection temperature under load (HDT): AST
Complies with MDD648. (Load: 18.6 kilograms per square centimeter) (3) Body oiliness: A test piece for evaluating tensile properties was immersed in oil (Mobil SHC-629) heated to 140 ° C.
Evaluated by change in tensile strength with time.

(4) Intrinsic viscosity: measured at 35 ° C. using an Ostwald viscometer using m-cresol as a solvent.

[0055]

Examples 1-4 and Comparative Examples 1-5 110 ° C., 10 To
Nylon 46 resin with an intrinsic viscosity of 1.42 (“STANYL” DSM, The Netherlands) dried for 12 hours under reduced pressure of rr
/ Propylene copolymer containing maleic anhydride in its molecular chain (olefin-based copolymer 1, "EXX")
ELAR VA1801 (manufactured by Exxon) or a styrene-ethylene / butadiene-styrene block copolymer containing maleic anhydride in the molecular chain (olefin copolymer 2, "Clayton FG1901X" Shell Chemical Co., Ltd.)
), Hydrotalcite (“DHT-4A · 2”, manufactured by Kyowa Chemical Co., Ltd.), and glass fiber (manufactured by Nippon Electric Glass Co., Ltd.) in the amounts shown in Table 1 beforehand in a tumbler. After uniform mixing, the cylinder temperature was adjusted to 3 using a twin screw extruder with a screw diameter of 44 mm and vented.
30 ° C, screw rotation speed 160rpm, discharge amount 40kg
/ H, and the threads discharged from the dies were cooled and cut to obtain molding pellets.

Next, the pellets were used in an injection molding machine having an injection capacity of 5 ounces and a cylinder temperature of 300 ° C., a mold temperature of 120 ° C., an injection pressure of 800 kg / cm 2, a cooling time of 15 seconds, and a total molding cycle of 40 seconds. A molded product for measuring each characteristic was molded.

Each characteristic was measured using these molded articles. Before measurement, 23
Conditioning was performed for 88 hours in an atmosphere at 50 ° C. and a relative humidity of 50%. Table 1 shows the results.

[0058]

[Table 1]

Nylon 46 resin is excellent in heat resistance represented by HDT and toughness represented by impact strength, and also exhibits high tensile strength. However, when immersed in oil at a high temperature of 140 ° C., the decrease in tensile strength is extremely low. (Comparative Example 1).

Even if the above-mentioned olefin copolymer is blended therein, its oil resistance is not improved, and the impact strength is increased, but the HDT is greatly reduced and the characteristics of nylon 46 resin are lost (Comparative Example 2, Comparative Example 2). 3). Further, when glass fiber is blended with nylon 46 resin, the tensile strength and HDT are improved, and the tensile strength after immersion in high-temperature oil is maintained, but the impact strength is reduced and the toughness is reduced. (Comparative Examples 4 and 5).

However, when glass fiber and the above-mentioned olefin-based copolymer are simultaneously added to the nylon 46 resin, not only excellent in tensile strength, HDT and impact strength, but also in tensile strength after immersion in high-temperature oil. Almost no decrease is observed (Examples 1 to 3). The oil resistance is higher than that of the glass fiber alone having a higher content in the composition (Comparative Example 4), and it can be seen that the oil resistance is exhibited by the layer action of the glass fiber and the olefin-based copolymer.

When hydrotalcite is added to these compositions, the oil resistance can be further improved, and the utility value of nylon 46 resin can be further enhanced (Example 4).

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-138366 (JP, A) JP-A-3-243657 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 77/00-77/12

Claims (2)

(57) [Claims] 1. (A) 3 to 40 parts by weight of an olefin copolymer containing a carboxylic acid or a derivative thereof in a molecular chain per 100 parts by weight of a nylon 46 resin, and (C) a fibrous reinforcing material 3 To 100 parts by weight, and (D) hydrotal
A resin composition comprising 0.01 to 3 parts by weight of a site . 2. The composition according to claim 1, wherein the component (C) is glass fiber.
3. The resin composition according to item 1.