JPH1135751A - Filament fiber-reinforced thermoplastic resin composition and molded product therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a filament fiber-reinforced thermoplastic resin composition high in mechanical strength and excellent in weatherability and bleed resistance of weathering agents and a molded product using the same. SOLUTION: This resin composition comprises a filament fiber-containing resin molded product obtained by impregnating a roving of filament fibers with a molten thermoplastic resin, then subjecting the resin-impregnated roving to pultrusion and cutting the obtained product into a length of 5-30 mm, a hindered amine-based weathering agent and a thermoplastic resin. In this case, the fiber content in the composition is 5-80 wt.% and the hindered amine-based weathering agent is 0.01-2 wt.%. It is preferred that the fiber is a glass fiber and the thermoplastic resin is a polypropylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a long fiber reinforced thermoplastic resin composition and a molded article using the same. More specifically, since the fiber can be kept in a relatively long state and the bleeding of the weathering agent (hereinafter referred to as bleed) can be prevented, the mechanical strength is high, and the long fiber has excellent weather resistance and bleeding resistance of the weathering agent. The present invention relates to a reinforced thermoplastic resin composition and a molded article using the same.

[0002]

2. Description of the Related Art Conventional fiber-reinforced thermoplastic resin molded products obtained from a thermoplastic resin composition containing reinforcing fibers are exposed to the surface of the molded product due to slight surface deterioration.
Since the physical properties of the molded article, particularly the mechanical strength, are significantly reduced, extreme care must be taken for surface deterioration due to ultraviolet rays. In order to solve only the surface deterioration of the molded article, it is effective to use a high molecular weight hindered amine-based weathering agent. However, in order to improve the weather resistance of the molded article, it is necessary to use a large amount of a weathering agent. Therefore, the application of such a molded article to the outer shell member is limited.

[0003]

The present inventors have conducted intensive studies in view of the above problems, and as a result, have found that it is effective to use a specific long-fiber-containing resin molded article and a specific weathering agent. Based on this finding, the present invention has been completed. As is apparent from the above description, an object of the present invention is to provide a long-fiber-reinforced thermoplastic resin composition having high mechanical strength and excellent bleeding resistance of a weathering agent and a weathering agent, and a molded article using the same. Things.

[0004]

The composition of the present invention is obtained by impregnating a roving made of filamentary fibers with a molten thermoplastic resin, drawing the molded product, and cutting it into a length of 5 to 30 mm. It is composed of the obtained long fiber-containing resin molded product, a hindered amine-based weathering agent having a molecular weight of 1,000 or more, and a thermoplastic resin, and the fiber content in the composition is 5 to 80% by weight, and the hindered amine-based weathering agent content is It can be easily obtained by adjusting the amount to be 0.01 to 2% by weight. Further, the molded article of the present invention can be easily obtained by using the composition of the present invention.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The present invention comprises a long-fiber-containing resin molded article, a hindered amine-based weathering agent and a thermoplastic resin,
Since a thermoplastic resin is also used when obtaining a long-fiber-containing resin molded article, the long-fiber-containing resin molded article and a hindered amine-based weathering agent have a fiber content of 5 to 80 wt% and a hindered amine-based resin. Only when a composition having a weathering agent content of 0.01 to 2% by weight can be obtained, the composition and molded article of the present invention may be obtained from the two components of the long fiber-containing resin molded article and the hindered amine weathering agent. .

As the thermoplastic resin used in the present invention, olefin resins, polyamides, polyesters and the like can be cited, and polypropylene is preferred from the viewpoint of weight reduction. Examples of the polypropylene include crystalline propylene homopolymer, crystalline propylene-α-olefin copolymer, and those obtained by modifying these homopolymers or copolymers with unsaturated carboxylic acids or anhydrides thereof. .

When polypropylene is used as a constituent component of the long-fiber-containing resin molded product, crystalline propylene-α having an α-olefin content of 8 to 10% by weight is taken into consideration in consideration of compatibility with fibers and fusibility. -Relative to the olefin copolymer, the unsaturated carboxylic acid or its acid anhydride is 0.1 to
Those modified by 1% by weight are preferred. Further, as the thermoplastic resin used together with the long fiber-containing resin molded product and the hindered amine-based weathering agent, a crystalline propylene homopolymer is preferable in consideration of rigidity.

As the fibers used in the present invention, known fibers such as glass fibers, carbon fibers, metal fibers, and polymer fibers can be used widely. These may be used alone or in combination of two or more. Glass fibers are preferred from the standpoint of reinforcing effect and availability. As glass fiber, E glass (Electrical glass), C glass (Chemi
cal glass), A glass (Alkali glass), S glass (High strength glass), and glass such as alkali resistant glass melt-spun into filamentous fibers. The fiber used in the present invention has a fiber diameter of 3 to 21 μm, and has been subjected to some treatment (for example, a silane coupling agent treatment) for imparting or improving interfacial adhesion to a thermoplastic resin on the fiber surface. Are preferred. The use of the fiber makes it possible to obtain a molded product having good strength and appearance.

[0008] The long fiber-containing resin molded article used in the present invention is:
The roving of several thousand fibers is guided to an impregnating die, and the molten thermoplastic resin between the filaments is uniformly impregnated, and then cut to a required length (5 to 30 mm) to be easily obtained. Although possible, the production method is not particularly limited. The method for impregnation is not particularly limited, and a glass fiber roving is passed through a thermoplastic resin powder fluidized bed, and the thermoplastic resin powder is adhered thereto, and then heated to a temperature equal to or higher than the melting point of the thermoplastic resin. (Japanese Patent Publication No. 52-3985) and a method in which a fiber roving is impregnated with a molten thermoplastic resin using a crosshead die (Japanese Patent Application Laid-Open No. Sho 62-60625).
JP-A-63-432036, JP-A-63-264326, JP-A-1-208118), using a resin fiber, and after blending this with a glass fiber roving, the melting point of the resin Any method such as the method of impregnating the resin by heating as described above (JP-A-61-118235) can be used.

The hindered amine weathering agent used in the present invention has a molecular weight of 1,000 or more. Molecular weight 10
If it is less than 00, the hindered amine-based weathering agent easily bleeds from the molded article. Preferably, the molecular weight is 1000-1
A range of 0000 is preferable. As the hindered amine-based weathering agent, specifically, dimethyl succinate 1- (2
-Hydroxyethyl) -4-hydroxy-2,2,6
6-tetramethylpiperidine polycondensate, poly [｛6-
(1,1,3,3-tetramethylbutyl) amino-1,
3,5-triazine-2,4-diyl {(2,2,
6,6-tetramethyl-4-piperidyl) imino {hexamethylene} (2,2,6,6-tetramethyl-4-
Piperidyl) imino}], N, N'-bis (3-aminopropyl) ethylenediamine 2,4-bis [N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino ] -6-chloro-1,3,5 triazine condensate and the like. Among them, poly [(6-morpholino-s-triazo-2,4-diyl)} 2,2,6
6-Tetramethyl-4-piperidyl) imino {-hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] is preferred. As a commercially available hindered amine-based weathering agent, a trade name “Siasorb UV334” is used.
6 ″ (Made by Cytec, molecular weight: 1600) is effective.
The amount of the hindered amine-based weathering agent to be added must be 0.01 to 2% by weight in the long fiber reinforced thermoplastic resin composition. If it is less than 0.01% by weight, sufficient weather resistance cannot be obtained, and if it exceeds 2% by weight, bleeding increases and the appearance of the molded product deteriorates.

The compositions and moldings according to the invention must have a fiber content in the range from 5 to 80% by weight. If the fiber content is less than 5% by weight, the mechanical strength is not sufficiently improved, and if it exceeds 80% by weight, the appearance of the molded article is deteriorated.

The composition and the molded article of the present invention contain various additives such as an antioxidant, an antistatic agent, a copper antioxidant, a neutralizing agent, a pigment and a dispersion within a range not to impair the object of the present invention. Agent, anti-aging agent, lubricant, mineral oil, silane coupling agent,
An additive such as a titanate coupling agent can be appropriately compounded.

The following method is effective as an example of a method for obtaining the long fiber reinforced thermoplastic resin composition used in the present invention. First, a masterbatch (U) in which a thermoplastic resin and a hindered amine-based weathering agent are mixed at a predetermined mixing ratio.
V) is obtained in the form of pellets by a general thermoplastic resin extruder to obtain a molded product (UV). Next, in a tumbler, the molded body (UV) and the long fiber-containing resin molded body,
A long-fiber-reinforced thermoplastic resin composition is obtained by mixing a thermoplastic resin for adjusting the composition and various additives as necessary.

The molded article of the present invention can be easily molded from the above-mentioned long fiber reinforced thermoplastic resin composition by a general thermoplastic resin molding machine. At this time, it is desirable to perform molding while adjusting the fibers contained in the molded article to have an average fiber length of 0.8 to 30 mm. When the average fiber length of the fibers in the molded article is less than 0.8 mm, the mechanical strength and impact strength of the molded article are not sufficiently exhibited, and the average fiber length of the fibers in the molded article exceeds 30 mm. In this case, moldability deteriorates. Factors that vary the average fiber length in the molded product include the specifications of the molding machine, molding conditions, gate diameter, fiber content, molten resin viscosity, and the like. Among them, the specifications of the molding machine, particularly the screw used, are a major factor. However, in the composition of the present invention, the average fiber length of the fibers in the molded product does not significantly fall below 0.8 mm as long as a general thermoplastic resin molding machine is used.

[0014]

EXAMPLES Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention should not be limited by these.

Test method (measurement of average fiber length) Long fiber-containing resin molded article (GF1),
Short fiber-containing resin molded product (GF2) and Examples 1-4
Each sample (approximately 5 g) obtained in Comparative Examples 1 to 3 was left in an electric furnace set at 600 ° C. for 5 hours, carbonized, and then the carbide was stirred in water, transferred to a glass petri dish and dried. Only the fiber portion was taken out, and the length of the taken out fiber was measured. The average of these fiber lengths was calculated and defined as the average fiber length. (Tensile Test) The tensile strength of each sample obtained in Examples 1 to 4 and Comparative Examples 1 to 3 was measured according to JIS K7113. (Bleed Resistance Test) Examples 1-4 and Comparative Examples 1-3
Each sample obtained in the above was used as a sunshine weather ometer (Suga Test Instruments Co., Ltd.) set at 63 ° C with rain.
And the time until the weathering agent bleeds on the surface of each sample was measured. The larger the value, the better the bleeding resistance. (Weather resistance test) Each sample obtained in Examples 1 to 4 and Comparative examples 1 to 3 (test piece according to JIS K7113)
Was left in a sunshine weather o-meter (manufactured by Suga Test Instruments Co., Ltd.) set at 63 ° C. with rain.
The samples were taken out at predetermined time intervals, and the tensile strength of each sample was measured. The measurement was repeated until the measured value became 50% or less of the measured value obtained in the above (tensile test), and the standing time until the measured value became 50% or less was measured. The larger the value, the better the weather resistance.

Examples 1-4 and Comparative Examples 1-3 Long-fiber-containing resin moldings (GF1), short-fiber-containing resin moldings (GF2), weathering agent masterbatch compositions (UV1, UV2) and formulations shown below A thermoplastic resin for composition adjustment (PP for dilution) was blended in the ratio shown in Table 1, and after dry blending, a cylinder temperature of 250 ° C. and a mold temperature of 50 were used.
Each sample was molded by an injection molding machine in which a full flight screw having a temperature of 30 ° C., a pressure in a mold of 30 MPa, and a compression ratio of 1.7 was used, and the clearance of a molten resin passage portion was set to 5 mm.
At this time, a mold that can obtain a test piece according to JIS K7113 was used. The average fiber length and various physical properties of each of the obtained samples were measured according to the above-mentioned test methods (mean fiber length measurement, tensile test, bleed resistance test, weather resistance test). Table 1 shows the results.

Long Fiber-Containing Resin Molded Body (GF1) A glass fiber obtained by roving a filamentous glass fiber having a fiber diameter of 17 μm into thousands of pieces is led to an impregnation die, and the melt flow rate melted between the filaments is 120 g / g.
10 minutes (temperature 230 ° C., load 2.16 kgf), impregnated with a crystalline propylene polymer grafted with maleic anhydride 0.2% by weight, cut into a length of 6 mm, and cut glass fiber into 50% by weight. The obtained long fiber-containing resin molded product (GF1) was obtained. When the average fiber length in the obtained molded body was measured according to the above (measurement of average fiber length), it was 6 mm, which is the same as the length of the molded article. Short fiber-containing resin molded product (GF2) Melt flow rate is 120 g / 10 min (temperature 23
0 ° C., load 2.16 kgf), a crystalline propylene polymer 5 grafted with 0.2% by weight of maleic anhydride
A composition consisting of 0% by weight and 50% by weight of chopped strand glass fiber having a fiber diameter of 17 μm and a fiber length of 3 mm,
The mixture was melt-kneaded by a twin-screw extruder to obtain a short fiber-containing resin molded product (GF2). When the average fiber length in the obtained molded body was examined in accordance with the above (measurement of average fiber length), it was cut to 0.6 mm, which corresponds to さ に of the length before compounding. Weatherproofing Masterbatch Composition (UV1) Poly [(6-morpholino-s-triazo-2,4-diyl) {2,2,6,6-tetramethyl-4-piperidyl) imino} -hexamethylene having a molecular weight of 1600 ｛(2,
2,6,6-tetramethyl-4-piperidyl) imino}] (trade name "Siasorb UV3346" (manufactured by Scitech)) and a melt flow rate of 20%
g / 10min (temperature 230 ° C, load 2.16kgf)
Was melt-kneaded with an extruder to obtain a pellet-shaped weathering agent master batch composition (UV1). Weatherproofing Masterbatch Composition (UV2) Bis (2,2,6,6-tetramethyl) having a molecular weight of 480
4-piperidyl) sebacate (trade name “TINUVIN”
A composition comprising 10% by weight of 770 "(manufactured by Ciba Geigy) and 90% by weight of a crystalline propylene polymer having a melt flow rate of 20 g / 10 min (temperature 230 ° C., load 2.16 kgf) is melted by an extruder. The mixture was kneaded to obtain a pellet-shaped weathering agent master batch composition (UV2) Thermoplastic resin for adjusting the composition (PP for dilution) As the thermoplastic resin for adjusting the composition (PP for dilution),
Melt flow rate is 20g / 10min (temperature 230
A crystalline propylene polymer having a load of 2.16 kgf) was used.

[0018]

[Table 1]

From the results in Table 1, it is found that each of the samples of Examples 1 to 4 which are molded articles of the present invention are molded articles using a short fiber-containing resin molded article (GF2) corresponding to a conventional molded article. It can be seen that, as compared with the samples of Examples 1 and 2, not only the mechanical strength is high, but also the bleed resistance and the weather resistance are excellent. The samples of Examples 1 to 4
Bleed resistance and weather resistance are extremely excellent as compared with the sample of Comparative Example 3 obtained by blending a low molecular weight weathering agent different from the high molecular weight hindered amine weathering agent, which is an essential component of the present invention. I understand. Further, Examples 1 to
Since each sample obtained in 4 can hold the fiber in a sample (molded article) in a long state, it can be seen that the mechanical strength is extremely high.

[0020]

Since the present invention is a special long-fiber-reinforced thermoplastic resin composition, the molded article of the present invention obtained by using the composition has high mechanical strength and bleed resistance of the weathering agent. And it is excellent in weather resistance, and is extremely suitable for outer shell members.
Therefore, it is extremely useful for various cable closures, power tool bodies and automobile outer panels.

Claims (7)

[Claims] 1. A long-fiber-containing resin molded product obtained by impregnating a roving made of filamentary fibers with a molten thermoplastic resin, followed by drawing and cutting into a length of 5 to 30 mm. A composition comprising the above hindered amine-based weathering agent and a thermoplastic resin, wherein the fiber content in the composition is 5 to 80% by weight, and the hindered amine-based weathering agent content is 0.01 to 2% by weight. A long-fiber-reinforced thermoplastic resin composition, characterized in that: 2. The long fiber reinforced thermoplastic resin composition according to claim 1, wherein the fibers are glass fibers. 3. The long fiber reinforced thermoplastic resin composition according to claim 1, wherein the thermoplastic resin is polypropylene. 4. A molded article characterized by using the long fiber reinforced thermoplastic resin composition according to claim 1. 5. The method according to claim 1, wherein the fibers present in the molded article have an average diameter of 3 to 3.
5. An average fiber length of 0.8 to 30 mm at 21 .mu.m.
The molded article as described. 6. The molded article according to claim 4, wherein the fibers are glass fibers. 7. The molded article according to claim 4, wherein the thermoplastic resin is polypropylene.