JPH0749515B2 - Resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polycyanoaryl ether resin composition, and more specifically, to a polycyanoaryl ether compounded with a specific fibrous filler and a non-tackifying agent. The present invention relates to a resin composition useful as a raw material for molded articles having excellent mechanical properties and sliding characteristics.

[Problems to be Solved by Prior Art and Invention]

Polycyanoaryl ether is known as an engineering plastic excellent in heat resistance, flame retardancy, chemical resistance and the like. However, this resin alone does not have sufficient rigidity (elastic modulus), and in the field of machine parts and the like where high rigidity is required, by filling with a fibrous reinforcing material such as glass fiber or carbon fiber. The application of compositions with improved stiffness has been investigated.

However, the composition filled with glass fiber or carbon fiber has a problem that the anisotropy of molding shrinkage is large and the surface appearance is rough. Furthermore, for parts such as bearings and gears that require mechanical properties at high temperatures as well as surface smoothness, sliding characteristics, and high dimensional stability, surface smoothness is low, friction and wear are large, and sliding There is a drawback in that the dimensional accuracy is not sufficient because the mating material is damaged during movement and the anisotropy is large. For these reasons, application is limited in mechanical parts and their peripheral fields.

Therefore, the present inventor intends to develop a polycyanoaryl ether resin composition which is excellent in surface smoothness, rigidity, sliding characteristics and dimensional accuracy and can be used as a material for a molded product that does not damage the mating material during sliding. , Repeated intensive research.

[Means for Solving the Problems]

As a result, they have found that the above problem can be solved by blending a polycyanoaryl ether having a repeating unit of a specific structure with a fibrous filler having a Mohs hardness of 6 or less and a non-tackifier. The present invention has been completed based on such findings.

That is, the present invention has the formula The present invention provides a resin composition comprising a polycyanoaryl ether having a repeating unit represented by the following as a main constituent, a fibrous filler having a Mohs hardness of 6 or less, and a non-tackifying agent.

The polycyanoaryl ether used in the present invention may be one having a repeating unit represented by the formula (I) as a main constituent component, and its specific ratio varies depending on the type and the like, and is not necessarily uniquely determined. However, it is generally preferable that the content of the repeating unit of the above formula (I) is 90% by weight or more. Also, a small amount, preferably 10
If less than wt%, the general formula Etc. ] The repeating unit or formula The repeating unit represented by may be included.

However, if the content of the repeating units of the general formulas (II) and (III) is 10% by weight or more, the characteristics of the polycyanoaryl ether may be impaired, which is not preferable.

The above-mentioned polycyanoaryl ether has, for example, the general formula [In the formula, X and X'represent a halogen atom. ] It is manufactured by reacting a dihalogenobenzonitrile represented by the following formula and resorcin in an equimolar ratio in the presence of an alkali metal carbonate in an aprotic polar solvent in an inert gas atmosphere.

Here, as the alkali metal carbonate, for example, sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate,
Carbonates such as rubidium carbonate and the corresponding hydrogencarbonates can be used. The amount of these alkali metal carbonates used may be appropriately selected depending on the situation, and is generally 1.0 to 1.3 times equivalent to resorcin, and in the case of hydrogen carbonate, 2.0 to 2.6 times equivalent to resorcin. It is particularly preferable that the amount is slightly excessive.

Examples of the aprotic polar solvent that can be used include N-methylpyrrolidone, 1,3-dimethylimidazolidinone, dimethylsulfoxide, dimethylformamide, dimethylacetamide, and the like. The amount may be sufficient to dissolve the compound of 1 and resorcin.

Furthermore, before or during the polymerization reaction, a chain extender or a terminal terminator, such as fluorobenzonitrile, can be appropriately added.

Other reaction conditions vary depending on various situations and cannot be uniquely determined, but the reaction temperature is usually 200 ° C. or higher, preferably 200 to 210 ° C., and the reaction time is 2 to 6 hours.

There are various polycyanoaryl ethers thus obtained, and the polycondensation is not particularly limited, but a reduced viscosity of a solution of 0.2 g / dl concentration using p-chlorophenol as a solvent at 60 ° C. is 0.3 to 2.0 dl / g, especially 0.6 ~
It is preferably 1.5 dl / g.

In the resin composition of the present invention, the compounding ratio of the above polycyanoaryl ether is not particularly limited, but is preferably
It is selected in the range of 20 to 95% by weight. Here, if the proportion of the polycyanoaryl ether is less than 20% by weight, the problem of poor molding (lack of fluidity) occurs, and if it exceeds 95% by weight, the intended modifying effect is not sufficiently exhibited.

The resin composition of the present invention is obtained by blending the above polycyanoaryl ether with a fibrous filler having a Mohs hardness of 6 or less and a non-tackifier.

The fibrous filler used in the present invention improves the rigidity, anisotropy and dimensional stability of the polycyanoaryl ether, is a reinforcing material for preventing damage to the mating material, and has a Mohs hardness. A fiber having an average fiber length of 5 to 100 μm and an average fiber diameter of 0.05 to 2 μm, preferably an average fiber length of 20 to 50 μm and an average fiber diameter of 0.1 to 0.5 μm
Used. Further, although the fiber can be used without treatment, a surface treatment agent such as a silane coupling agent or a titanate coupling agent can be used in order to have an affinity with the polycyanoaryl ether. This fibrous filler is contained in the resin composition of the present invention in an amount of 3 to 70% by weight.
It is preferably included. If this amount is less than 3% by weight, the effect will be insufficient, but if it is too large, there will be disadvantages such as loss of surface smoothness.

Examples of the fibrous filler that can be used in the present invention include potassium titanate whiskers and wollastonite. Here, as the potassium titanate whiskers, commercially available ones may be used. For example, Tismo D 101 (Mohs hardness 4.0, average fiber length 20 μm, manufactured by Otsuka Chemical Co., Ltd.,
An average fiber diameter of 0.1 μm), B type (Mohs hardness of 4.0, average fiber length of 45 μm, average fiber diameter of 0.5 μm) manufactured by Kubota Tekko KK can be preferably used. Wollastonite is a cyclosilicate of calcium, iron, and manganese, which is also called wollastonite, and a commercially available product can be used for this.
For example, Maruwa Biochemical Co., Ltd. chemolite (Mohs hardness
4.5, average fiber length 20 μm, average fiber diameter 0.16 μm) and the like.

On the other hand, there are various non-tackiness-imparting agents, and examples thereof include fluororesin, graphite, molybdenum disulfide, and the like. Among these, polytetrafluoroethylene and graphite are particularly preferable. The particle size of the non-tackifying agent is
There is no particular limitation, and various types can be used, but generally, the average particle size is 0.5 to 50 μm, preferably 1 to 30 μm.
Use m. This non-tackifying agent may be a commercially available product, but specifically, it is polytetrafluoroethylene (trade name: Lubron L-2, L manufactured by Daikin Industries, Ltd.).
-5: Average particle size 5μ, 7μ), scaly graphite manufactured by Nippon Graphite Industry Co., Ltd. (trade name CSSP: average particle size 1 μm, ACP-1000: average particle size 6μ
m), molybdenum disulfide manufactured by Nippon Graphite Industry Co., Ltd. (Mori powder B: average particle size 5 μm), PFA manufactured by Mitsui DuPont Fluorochemicals (trade name Teflon PFA-1), and the like. The non-tackifying agent can be mixed in the resin composition of the present invention in various proportions, but it is usually preferable to be contained in the resin composition in an amount of about 2 to 40% by weight. If this amount is too small, the effect will not be exhibited, but if it exceeds 40% by weight, the mechanical strength will be lowered.

The resin composition of the present invention includes, in addition to the above fibrous filler and non-tackifying agent, additives commonly used in this type of resin composition, for example, reinforced filling of glass fiber, carbon fiber and the like. Agents, antioxidants, ultraviolet absorbers, lubricants, release agents, colorants or inorganic fillers such as talc and mica can be added.

In order to produce the resin composition of the present invention, the polycyanoaryl ether is blended with a fibrous filler, a non-tackifying agent, and optionally other additives in the above mixing ratio, and this is mixed in a conventional manner. Therefore, it may be melt-kneaded. The temperature at this time is usually 350 to 400 ° C, preferably 350 to 370 ° C,
The kneading time is 1 to 10 minutes, preferably 2 to 5 minutes.

The resin composition thus obtained is optionally pelletized using a single-screw or twin-screw extruder and molded by injection molding or the like.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Production Example (Production of Polycyanoaryl Ether) 2,6-Dichlorobenzonitrile 103 was placed in a separable three-necked flask equipped with a stirrer and an argon blowing tube.
05g (59.91mol), resorcin 6607g (60mol), sodium carbonate 6995g (66mol), N-methylpyrrolidone 75
And toluene 3 were added, and the mixture was stirred at 200 ° C. for 3 hours.
To this, 104 g (0.75 mol) of 2,6-difluorobenzonitrile as a chain extender was added, and the mixture was further stirred for 2 hours. Then, 417 g of difluorobenzonitrile as a terminal stopper
(3 mol) was added and reacted for 15 minutes. Methyl ethyl ketone was added to the obtained polymer solution to precipitate a polymer powder, which was separated by filtration. Then, N-methylpyrrolidone-
The mixture was washed successively with a mixed solution of methyl ethyl ketone, acetone and water to obtain a polymer powder. This polymer is a solution of p-chlorophenol at a concentration of 0.2 g / dl at 60 ° C.
The reduced viscosity was 1.2 dl / g. Further, this polymer has the following repeating units.

Examples 1 to 8 and Comparative Examples 1 to 4 Polycyanoaryl ether having a reduced viscosity of 1.2 dl / g prepared in the above Production Example, a fibrous filler and a non-tackifying agent were mixed in the composition shown in Table 1. Then, the mixture was melt-kneaded at a temperature of 355 ° C. by a twin-screw extruder (PCM-30 manufactured by Ikegai Tekko Co., Ltd.), and the obtained strand was water-cooled and cut to obtain pellets.

The obtained pellets are 80 × 80 × 3.2m with an injection molding machine (Toshiba IS45P) at a cylinder temperature of 360 ° C and a mold temperature of 200 ° C.
Injection molding was performed on a flat plate of m to obtain a test piece for measuring the molding shrinkage and the bending elastic modulus. Furthermore, 30 × 30 × 3.2m from this plate
A flat plate of m was cut and used as a test piece for measuring sliding characteristics.

Mold shrinkage, flexural modulus, friction coefficient, wear coefficient, and mating material damage were tested by the following test methods.

(A) Mold Shrinkage A test piece for measuring mold shrinkage was obtained by injection molding a resin composition from a film gate having a thickness of 1 mm on one side of 80 mm of a flat plate mold of 80 × 80 × 3.2 mm. 80 × of the base of the test piece
The shrinkage ratio with respect to the length of 80 × 3.2 mm was represented by MD (machine direction) in the flow direction of the resin composition and TD (transverse direction) in the direction perpendicular to the flow.

(B) Flexural modulus Measured according to ASTM D 790.

(C) Sliding characteristics Using a thrust wear tester (Friction wear tester EFM-III-F manufactured by Orientec Co., Ltd.), friction was performed with S45C as the mating material under a pressure of 7 kg / cm ² and a speed of 15 m / min. The coefficient and wear coefficient were measured.

The degree of damage to the mating material was visually observed.

The test results are shown in Table 2.

[Effects of the Invention] According to the present invention, as compared with a conventional resin composition containing a polycyanoaryl ether as a main component, it has high rigidity over a wide temperature range, and has a small friction coefficient and wear coefficient,
It is possible to obtain a resin composition which produces a molded article having excellent sliding properties.

Therefore, the resin composition of the present invention is suitable for molding sliding parts such as bearings and gears, and is expected to be effectively used in the field of sliding equipment.

Claims (2)

[Claims] 1. A formula A resin composition comprising a fibrous filler having a Mohs hardness of 6 or less and a non-tackifying agent selected from polycyanoaryl ether having a repeating unit represented by the following as a main constituent, potassium titanate whiskers, and wollastonite. 2. 20 to 95% by weight of the polycyanoaryl ether according to claim 1, 3 to 70% by weight of a fibrous filler having a Mohs hardness of 6 or less, selected from potassium titanate whiskers and wollastonite, and non-adhesive. A resin composition comprising 2 to 40% by weight of an imparting agent.