WO2007074877A1

WO2007074877A1 - Method for production of long fiber-reinforced polyolefin resin molding material

Info

Publication number: WO2007074877A1
Application number: PCT/JP2006/326110
Authority: WO
Inventors: Masahiko Tominaga
Original assignee: Ocv Intellectual Capital, Llc
Priority date: 2005-12-27
Filing date: 2006-12-27
Publication date: 2007-07-05
Also published as: JP2007177028A; CN101365738A; JP5037820B2; CN101365738B

Abstract

Disclosed is a method for production of a long fiber-reinforced polyolefin resin molding material having excellent mechanical strength and durability, which can achieve the charge/feeding of a matrix resin into an immersion die by means of a single-screw extruder in a stable manner. The method comprises the steps of: plasticizing/melting a composition comprising a base resin and a master batch in a single-screw extruder; charging the resulting composition into an immersion die; passing a reinforcing fiber through the immersion die; and cutting a long fiber-reinforced polyolefin resin rod thus produced into pieces each having a predetermined length, wherein the base resin comprises a polyolefin resin, and the master batch is prepared by previously melting/dispersing an additive comprising a low-melting-point additive having a melting point of 125˚C or lower (i.e., a master batch component other than a polyolefin resin) into a polyolefin resin.

Description

Specification

Method for producing long fiber reinforced polyolefin resin molding material

Technical field

The present invention relates to a method for producing a long fiber reinforced polyolefin resin molding material used for obtaining a molded article having excellent mechanical strength and good appearance.

Background art

[0002] Polyolefin resin such as polypropylene resin is an inexpensive and lightweight material, and is a resin molding material that is widely used because of its easy molding. In order to improve the mechanical properties, particularly impact resistance, a long fiber reinforced polyolefin resin molding material in which a polyolefin fiber is impregnated into a reinforcing fiber such as glass fiber is known.

[0003] Such a long fiber reinforced polyolefin resin molding material, for example, a polyolefin resin used as a matrix resin is plasticized and melted by an extruder, and the molten polyolefin resin is filled in an impregnation die. At the same time, the reinforcing fiber drawn from the rotary body or the like is passed through the impregnation die, so that the reinforcing fiber is impregnated with the resin, and pulled out through the nozzle to obtain a predetermined shape. It is manufactured by shaping and cutting continuous reinforcing fiber.

[0004] On the other hand, polyolefin resin has a tendency to deteriorate due to the effects of oxygen, heat, light, etc., and is easily affected by these effects. Therefore, for example, as disclosed in Patent Document 1 below, in addition to the polyolefin resin, an antioxidant and a light stabilizer, an ultraviolet absorber, etc. are added to the polyolefin resin molded product to prevent acid resistance. It has improved durability such as chemical degradation, heat resistance, and weather resistance.

Patent Document 1: JP-A-9-207233

Disclosure of the invention

Problems to be solved by the invention

[0005] In general, single-screw extruders and twin-screw extruders are known as matrix resin resins used in the production process of long fiber reinforced polyolefin molding materials. In order to supply the same amount of molten matrix resin to the impregnation die, a single screw extruder is used. Compared to an extruder, the equipment cost is low, and the screw structure is not complicated. Therefore, there is an advantage that cleaning at the time of switching the molten resin material can be performed quickly and easily.

[0006] When a single-screw extruder is used as an extruder in the production of a long fiber reinforced polyolefin resin molding material, the impregnation die is filled with a plasticized and melted matrix resin. At this time, the supply of the matrix resin to the impregnation die becomes unstable, and there is a problem that poor filling occurs and it is difficult to adjust the supply amount of the matrix resin to the impregnation die immediately. For this reason, the amount of the resin supplied to the impregnation die is not stable, and the resin may not spread to the opening bar, etc., and the fiber breakage of the reinforcing fibers is likely to occur, and the long fiber reinforced polyolefin resin molding Inferior material productivity had a problem.

Accordingly, an object of the present invention is to provide a long-fiber reinforced polyolefin having excellent mechanical properties and durability, capable of stably filling and supplying matrix resin to an impregnation die using a single screw extruder. It is providing the manufacturing method of a resin molding material.

Means for solving the problem

[0008] In achieving the above object, the present inventor added a powdery antioxidant, a light stabilizer, an ultraviolet absorber, etc., as a cause of a steep decrease in the amount of supply of fat and an unstable cause. When it was considered that this was caused by the use of chemicals, it was found that there are many problems that cause significant problems when using these additives with low melting points. .

[0009] On the other hand, even when the above-mentioned various additives having a relatively high melting point are used, there are many resins having a melting point lower than that of the polyolefin resin, which is the main raw material. It was sufficient, and again, poor filling of the matrix resin impregnation die was likely to occur.

[0010] In addition, in order to improve the durability of the resin product, such as heat resistance, acid resistance, and deterioration resistance, it is effective to use a combination of a plurality of additives. If it cannot be used, the types of additives that can be selected will be limited, so the effect will be severely limited and the required performance may not be obtained.

[0011] It is also conceivable to produce a long fiber reinforced polyolefin resin composition using a matrix resin that does not contain additives, but it has excellent durability such as oxidation resistance, heat resistance, and weather resistance. Long-fiber-reinforced polypropylene resin molding materials and reinforcing fibers Necessary additives need to be blended when kneading and molding a dilution polypropylene resin containing no fiber into a molded product. However, when kneading the long fiber-reinforced polypropylene resin molding material, diluting polypropylene resin, and additives, the additives are classified according to the difference in particle size. There was a problem of loss of productivity.

[0012] Therefore, as a result of various studies, the present inventor has previously melted and dispersed additives such as an antioxidant, a light stabilizer, and an ultraviolet absorber in a polyolefin resin to form a master batch, and then the polyolefin used as a base. It has been found that by using a mixture with a resin, it is possible to drastically and stably fill the impregnation die with the melt matrix resin in the single-screw extruder, and the present invention has been made.

[0013] That is, in the method for producing a long fiber reinforced polyolefin resin molding material of the present invention, the polyolefin resin composition is plastic-melted by a single screw extruder and filled into an impregnation die. In the method for producing a long-fiber reinforced polyolefin resin composition, the long-fiber-reinforced polyolefin resin rod is cut into a predetermined length, and the polyolefin resin composition is used as the polyolefin resin composition. A mass obtained by pre-melting and dispersing in a polyolefin resin an additive containing a low-melting-point additive having a melting point of 125 ° C or lower, which is a component of a master batch (excluding polyolefin resin). And a composition containing a tarbatch.

In the present invention, the polyolefin resin of the master batch preferably has an MFR of 5 to 40 (gZ lOmin). According to this, since the kneadability of the additive and the polyolefin resin is improved, the content of the additive in the master batch can be increased. In addition, the shape and size of the master batch can be sufficiently adjusted by pelletizing, etc., so that the base resin and the master batch can be easily mixed, and the filling of the molten matrix resin into the impregnation die is stabilized. In addition, MFR means the mel flow rate value specified by JIS-K-7210, and indicates the amount of grease per 10 minutes when the cylinder force also flows at 230 ° C and a load of 2.16 kgf. If this MFR is high, it means that the viscosity of the resin is low.

[0015] The polyolefin resin of the base resin preferably has an MFR force of 0 to 200 (g / 10 min). According to this, the impregnation property to the reinforcing fiber becomes good and the mechanical strength is improved. An excellent long fiber reinforced polyolefin resin molding material can be obtained.

[0016] The polyolefin resin of the base resin and the polyolefin resin of the masterbatch are preferably polypropylene-based resins. Polypropylene-based resin is economical and general-purpose, and the base resin and master batch can be obtained by making the polyolefin resin of the base resin and the polyolefin resin of the master notch the same type of resin. And the filling of the molten matrix resin into the impregnation die becomes stable.

[0017] Preferably, the additive is at least one selected from an antioxidant, a light stabilizer and an ultraviolet absorber. By blending the above-mentioned additives into a long fiber reinforced polyolefin resin molding material, durability such as heat resistance and acid resistance deterioration of the polyolefin resin molded product obtained as a final product can be improved.

[0018] The masterbatch preferably contains 15 to 50% by mass of additives other than the polyolefin resin. Furthermore, the additive of the masterbatch preferably contains 30 to LOO% by mass of the low melting point additive. Furthermore, the polyolefin resin composition preferably contains 2 to 35 parts by mass of the masterbatch with respect to 100 parts by mass of the base resin.

The invention's effect

[0019] According to the present invention, in the production of a long fiber reinforced polyolefin resin molding material, it is possible to stably supply the matrix resin to the impregnation die using a single screw extruder, thereby reinforcing the long fiber reinforcement. The manufacturing cost and maintenance cost of the polyolefin resin molding material can be reduced.

[0020] Since the long fiber reinforced polyolefin resin molding material obtained by the present invention is a molding material containing additives such as an antioxidant, a light stabilizer, and an ultraviolet absorber, the molding material It is not necessary to add the above-mentioned additives in addition to the polyolefin resin for dilution without containing reinforcing fibers. That is, when a long-fiber reinforced polyolefin resin molding material, a dilution polyolefin resin, and an additive are melt-kneaded to form a resin molded product, the additive may be classified depending on the particle size and the like. However, according to the present invention, the above-mentioned long fiber reinforced polyolefin resin molding material and the dilution polyolefin resin are kneaded and molded without adding an additive, so that the oxidation deterioration resistance, heat resistance, Resin molded product that can be made into a resin molded product with good durability such as weather resistance and is difficult to classify Product production ^ fe will not be damaged.

Brief Description of Drawings

FIG. 1 is a basic configuration diagram showing a production process of a long fiber reinforced polyolefin resin molding material.

Explanation of symbols

[0022] 1: Reinforcing fiber

2: Molten resin supply route

3: Single screw extruder

4: Honoichi

5: Impregnation die

6: Nozzle

7: Long fiber reinforced polyolefin rod

8: Cooling tank

9: Picker

10: Pelletizer

11: Long fiber reinforced polyolefin resin molding material

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] In the method for producing a long fiber reinforced polyolefin resin molding material of the present invention, a polyolefin resin composition as a matrix resin is melted plastic by a single screw extruder and filled in an impregnation die. A long fiber reinforced polyolefin resin rod obtained by impregnating a reinforcing fiber with a polyolefin resin composition by passing the reinforcing fiber through an impregnation die is cut into a predetermined length.

[0024] As the reinforcing fiber, glass fiber, carbon fiber, metal fiber, high melting point fiber such as aromatic polyamide fiber, etc. can be used. These reinforcing fibers are used as fiber bundles obtained by bundling 100 to 10,000, preferably 400 to 6,000, of the single fibers with a commonly known sizing agent. Among these reinforcing fibers, glass fibers are preferable in consideration of the strength and price of the obtained long fiber reinforced polyolefin resin molding material. The diameter of the single fiber of the reinforcing fiber is preferably 6 to 30 μm, more preferably 9 to 23 μm.

[0025] The polyolefin resin composition used as a matrix resin for the reinforcing fiber of the present invention ( (Hereinafter referred to as “matrix resin”) is a low-melting additive with a melting point of 125 ° C or lower, which is a base resin composed of polyolefin resin and a master batch component (excluding polyolefin resin). It is a composition containing a master notch obtained by pre-melting and dispersing the additive contained in a polyolefin resin, and is a composition containing 2 to 35 parts by mass of a master batch with respect to 100 parts by mass of the base resin. U prefer that. If the content of the masterbatch is less than 2 in the above value, it is necessary to increase the additive content in the masterbatch in order to obtain the effectiveness of the additive that is difficult to obtain. This is not preferable because it becomes difficult. In addition, if the content of masterno << Tch exceeds 35 parts by mass, the material cost tends to increase, which is not preferable. Especially, it is more preferable that it is a composition containing 4-30 mass parts of master batches with respect to 100 mass parts of base resin.

[0026] The polyolefin resin of the base resin (hereinafter referred to as "base polyolefin resin") is a homopolymer or copolymer such as ethylene, propylene, butene, 4-methylpentene, vinyl acetate, Examples thereof include random, block or graft copolymers with polar monomers such as acrylic acid, acrylic acid ester and maleic anhydride. Of these, propylene homopolymers and graft polymers of polypropylene rosin and maleic anhydride are preferred because they are economical and versatile.

[0027] The MFR of the base polyolefin resin is preferably 20 to 200 (g / 10min). If the MFR is less than 20 (gZl0min), the impregnation of the reinforcing fiber is inferior, and if it exceeds 200 (g / lOmin), the impregnation is good. It is not preferable because the strength of the long fiber reinforced polyolefin resin molding material is inferior. The MFR of the base polyolefin resin is more preferably 50 to 150 (g / 10min).

[0028] As the master batch used for the matrix resin of the present invention, an additive containing a low melting point additive having a melting point of 125 ° C or lower, which is a component of the master batch (excluding polyolefin resin), is polyolefin. A master batch obtained by previously melting and dispersing in a resin is used.

[0029] As the polyolefin resin (hereinafter referred to as "MB polyolefin resin") for obtaining the above masterbatch, those similar to the base polyolefin resin without particular limitation can be used. Base polyolefin is preferred to be the same type of resin as the base polyolefin resin More preferably, the fin resin and the MB polyolefin resin are polypropylene resins. Polypropylene-based resin is economical and general-purpose, and also has a wide range of processing temperature conditions and MFR options, so that extrusion kneading can be easily performed when preparing the masterbatch. By making the base polyolefin resin and the MB polyolefin resin of the same system, the base resin and the master batch can be easily mixed, and the filling of the molten matrix resin into the impregnation die is stabilized. Here, examples of the polypropylene resin include a propylene homopolymer, a graft polymer of polypropylene resin and maleic anhydride, and a copolymer of propylene and ethylene.

[0030] The MFR of MB polyolefin resin is preferably 5 to 40 (g / 10 min), more preferably 10 to 30 (gZlOmin). If the MFR of the above MB polyolefin resin is less than 5 (gZlOmin), the difference in MFR value with the base polyolefin resin becomes large, and the master batch becomes difficult to disperse in the base polyolefin resin and is contained in the master batch. Are difficult to disperse uniformly in the long fiber reinforced polyolefin resin molding material. On the other hand, if the MFR force S40 (gZl0min) is exceeded, the kneading is insufficient during the kneading of the masterbatch, so the additive content cannot be increased. As a result, in order to contain the required amount of additive in the long fiber reinforced polyolefin resin molding material, it is necessary to increase the amount of the master batch, which is disadvantageous in terms of cost. Furthermore, during extrusion kneading for producing a master batch, the thickness of the melt-extrusion rod from the die for producing the master batch becomes uneven or too thin, and pelletizing (cutting) cannot be performed sufficiently. Since the masterbatch size and shape are likely to be non-uniform, the resulting long fiber reinforced polyolefin is inferior in meterability, and as the shape varies and the difference in shape increases, the mixing with the base polyolefin resin worsens. Variations in the additive content tend to occur in the resin molding material.

[0031] The additive used in the masterbatch of the present invention is an antioxidant, a light stabilizer, an ultraviolet absorber, etc. Among these additives, a melting point of 125 ° C or lower, more preferably a melting point of 100 °. It is essential that a low melting point additive (hereinafter also referred to as “low melting point additive”) having a melting point of not more than C, particularly preferably 40 to 80 ° C., in addition to the low melting point additive. More than C, more preferably a high melting point additive having a melting point of 150 ° C. or more (hereinafter also referred to as “high melting point additive”) may be used in combination. By using a combination of acid-proofing agents having a plurality of different melting points, it is possible to effectively improve the durability of the polyolefin resin-molded product, such as acid-resistant deterioration.

[0032] The additive used for the masterbatch contains a low-melting-point additive, preferably 30-: LOO mass%, more preferably 30-90 mass%, still more preferably 30-70 mass%. If the content of the low-melting-point additive is less than 30% by mass, effects such as improved durability due to the combined use with the high-melting-point additive may be obtained, and the effect of the additive may be insufficient. .

[0033] The content of the additive in the master batch is preferably 15 to 50% by mass, and more preferably 20 to 40% by mass. If the additive content of the masterbatch is less than 15% by mass, the amount of masterbatch used will increase, which tends to increase material costs. If it exceeds 50% by mass, it will be difficult to make a masterbatch. In addition, the stability as a master notch is inferior.

[0034] Antioxidant as a low melting point additive (melting point of 125 ° C or lower) is 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis- (4 ethyl) -6-tert-butylphenol), 2,6-di-tert-butyl-4-ethylphenol, n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenol) propionate, tetrakis [Methylene-3- (3,5-di-tert-butyl-4-hydroxyphenol) propionate] methane, triethylene glycol bis [3- (3-tert-butyl-4-hydroxy-5-methylphenol) Propionate], pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenol) propionate], diethylene-bis [3- (3,5-di-tert-butyl- 4-hydroxyphenol) propionate], 2,4-dimethyl-6- (1-methylpentadecyl) phenol, 4,6-bis (ota) Ruthiomethyl)-0-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di- tert-butyl-4-hydroxyphenol)] propionate, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazine-2-ilamino) phenol , Hindered phenolic antioxidants such as Jetyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenol] methyl] phosphonate; dilauryl thiopropionate, distearyl thiodipropio Acid, dimyristinorethiodipropionate, ditridecinoretiodipropionate, and other thioether antioxidants; bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl Ester phosphorous acid, tetrakis (2,4-di-tert-butylphenol) [1, 1-biphenyl] -4,4'-dirubisphosphonite, trinolephenol phosphonite, triphenyl phosphonate Phosphoric acid oxidants such as didodecyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate, dioctadecyl-3,3'-thiodipropionate And an anti-oxidation agent. In particular, when used in combination with a hindered phenolic acid antioxidant, a synergistic effect of thermal stability and an improvement effect such as durability are high, and thus a polyether ether acid antioxidant is particularly preferable. Are dimyristyl-3,3'-thiodibu oral pionate, dilauryl-3,3'-thiodipropionate, and distearyl-3,3'-thiodipropionate.

[0035] UV absorbers (melting point of 125 ° C or lower) as low melting point additives are 2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole, 2-2 ' -Hydroxy-5'-t-octylphenyl) benzotriazole and the like.

[0036] Examples of the light stabilizer (melting point of 125 ° C or lower) as the low melting point additive include bis (2, 2, 6, 6-tetramethyl-4-piperidyl) sebacate.

[0037] Antioxidant agents (melting point exceeding 125 ° C) as high melting point additives are 4, 4'-thiobis- (6-tert-butyl-3-methylphenol), 4, 4'- Butylidenebis- (6-tert-butyl-3-methylphenol), 2,2'-methylenebis- (4-methyl-6-tert-butylphenol), 1,1,3'-tris (2-methyl-4 -Hydroxy-5-tert-butylphenol) butane, N, Ν'-hexan-1,6'-dirubis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 3 , 3 ', 3 ", 5, 5', 5" -hexa-tert-butyl-a, a ', a',-(mesitylene-2,4,6- 卜 ylyl) tri-P-cresol, 1,3,5-tris [3,5-di-tert-butyl-4-hydroxybenzyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) _trione, 1, 3 , 5-tris [(4-tert-butyl-3-hydroxy-2,6-xylyl) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, Hindered phenolic antioxidants such as 2 ', 3-bis [3- (3,5-di-tert-butyl-4-hydroxyphenol) propiol] propionohydrazide; Tris (2, 4- Examples thereof include phosphoric acid inhibitors such as di-tert-butylphenol) phosphite and bis (2,4-di-tert-butylphenol) pentaerythritol diphosphonite. Of these, a combination of a hindered phenolic acid inhibitor and a phosphorus acid inhibitor is preferred. [0038] Ultraviolet absorbers (melting point above 125 ° C) as high melting point additives are 2- (5-methyl-2-hydroxyphenol) benzotriazole, 2- [2-hydroxy-3, 5 -Bis (α, αdimethylbenzyl) phenol] -2 --benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenol) benzotriazole, 2- (3-t -Butyl-5-methyl-2-hydroxyphenol) -5-Black mouth benzotriazole, 2- (3,5-di-t-butyl-2-hydroxy phenol) -5-Black mouth benzo And triazole.

[0039] The light stabilizer (melting point above 125 ° C) as a high melting point additive is 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonic acid Bis (1,2,2,6,6-pentamethyl-4-piperidyl), 2,4-di-t-butylphenyl-3,5-di-t-butyl 4-hydroxybenzoate, and the like.

[0040] Examples of additives other than antioxidants, ultraviolet absorbers, and light stabilizers include, for example, flame retardants; metal deactivators; magnesium stearate, calcium stearate, zinc stearate, barium stearate, stearin. Metal stalagmites such as aluminum oxide, lithium stearate, zinc laurate, barium laurate, barium p-t-butylbenzoate, zinc p-t-butylbenzoate; acid neutralizers such as hydrated talcite; dispersion Agent; lubricant; antistatic agent; plasticizer; mold release agent; crystallization accelerator (nucleating agent); antifogging agent; alkaline earth metal compound such as magnesium hydroxide and aluminum hydroxide; foaming agent; ; Antibacterial agents; Algae-proofing agents; Mold modifiers such as antifungal agents; Colorants such as carbon black, zinc sulfide, pigments, dyes; Titanium oxide, tar, calcium carbonate, My strength, clay, graph Particulate fillers such as eye and glass flakes; Organic fillers such as cellulose, bamboo fiber and aramide fibers; whiskers such as potassium titanate, etc., with melting point of 125 ° C or lower and additives exceeding 125 ° C These additives can be appropriately selected and used.

[0041] In addition to the base resin and the master batch, the matrix resin used in the present invention may further contain a low-melting additive, a high-melting additive, etc. that are not in a master batch. However, it is preferable that the resin composition comprises the base resin and the master batch.

In the present invention, the long fiber reinforced polyolefin resin molding material can be produced, for example, by a process as shown in FIG. [0043] First, a continuous reinforcing fiber 1 drawn from a rotating body force (not shown) is introduced into an impregnation die 5, and a matrix resin (polyolefin resin composition) having the above-described composition power supplied from a single screw extruder 3 is melted. Impregnated with reinforcing fiber 1 in the object. Here, in the single-screw extruder 3, a certain amount of matrix resin is supplied from the hopper 4, and the supplied matrix resin is melt-kneaded here, and from the molten resin supply path 2 to the impregnation die 5. Fill and supply molten matrix resin. The matrix resin having the above compositional power has good fluidity of the melted resin in the melt kneading in the single screw extruder 3, and therefore the impregnation die 5 in the single screw extruder 3 is filled with the molten resin. Supply can be performed stably.

Next, the reinforcing fiber 1 impregnated in the molten matrix resin is drawn out through the nozzle 6. As a result, excess matrix resin attached to the reinforcing fiber 1 is removed, and a desired long fiber reinforced polyolefin resin rod 7 having a predetermined fiber content and a predetermined cross-sectional shape is obtained. The long fiber reinforced polyolefin resin rod 7 is cooled in a cooling tank 8 and taken up by a take-up machine 9. The taken long fiber reinforced polyolefin resin rod 7 is cut to a predetermined length by a pelletizer 10 equipped with a rotary cutting blade, and a long fiber reinforced polyolefin resin molding material 11 is obtained.

[0045] The long fiber reinforced polyolefin resin molding material thus obtained contains reinforcing fibers having the same length in parallel and in the same direction in the polyolefin resin, which is a matrix resin. And speak. The shape of the long fiber reinforced polyolefin resin molding material is preferably a wire or pellet. Here, the reinforcing fibers are substantially the same length and are included in parallel in the same direction, which means that most of the reinforcing fibers are aligned in parallel in the same direction. In this case, some fibers may be partially bent and V entangled or entangled with each other.

[0046] The fiber content of the long fiber reinforced polyolefin resin molding material is not particularly limited, but is preferably 20 to 80% by mass, more preferably 30 to 75% by mass. If the fiber content is less than 20% by mass, the reinforcing effect by the reinforcing fibers cannot be sufficiently obtained. If the fiber content exceeds 80% by mass, the impregnation of the matrix resin is inferior, and it is immediately used in the nozzle drawing process described later! Since fuzz and disconnection are likely to occur, productivity is inferior.

[0047] The average diameter of the long fiber reinforced polyolefin resin molding material is 0.3 to 3.5 mm. It is more preferable that 0.4 to 3 mm is more preferable. If the average diameter is less than 0.3 mm, the bulk density of the molding material will be small, resulting in poor transportability. If the average diameter exceeds 3.5 mm, the dispersibility of the reinforcing fibers will be poor when molded by injection molding. Inferior.

[0048] The length of the long fiber reinforced polyolefin resin molding material is not particularly limited.

It is preferably 25 mm, more preferably 4 to 20 mm. If the length is less than 3 mm, cracking will occur when cutting with a pelletizer, etc. 10, and it will soon be difficult for the fiber reinforcement effect to be realized. If the length exceeds 25 mm, it will be molded by injection molding. At this time, it may be difficult to supply to the molding machine, and the dispersion of the reinforcing fibers and the fluidity may be reduced. Example

[0049] The present invention will be specifically described below with reference to examples. However, these examples are illustrative of embodiments of the present invention and are not intended to limit the scope of the present invention.

[0050] [Example 1]

Using the raw materials shown in Table 1 below, the matrix resin of Formulation Example 1 prepared at the mixing ratio shown in Table 2 was dissolved at 280 ° C at a screw speed of 50 rpm using a single screw extruder with a screw diameter of 65 mm. Then, molten matrix resin was supplied to the impregnation die, and the supply stability of the matrix resin was observed. In Example 1, antioxidants A and B were melt-dispersed in polypropylene resin B at 200 ° C. and used as a master batch (the content of an antioxidant was 25% by mass).

[0051] The stability of the resin supply is as follows: ○: [A certain amount of resin is supplied to the impregnation die from the single screw extruder], Δ: [Supply of the resin from the single screw extruder at the same screw speed as that of ○] There is little or the supply amount of the resin is increased or decreased.] X: [Single-screw extruder force No resin is supplied at all]. The evaluation results are shown in Table 2.

[0052] [Example 2]

The supply stability of the matrix resin was observed in the same manner as in Example 1 except that the raw material shown in Table 1 was used and the matrix resin of Preparation Example 2 prepared at the mixing ratio of Table 2 was used. In Example 2, antioxidant C was melt-dispersed in polypropylene resin B at 200 ° C. and used as a master batch. [0053] [Comparative Example 1]

Antioxidants A and B were not added as master batches to polypropylene resin A as a base resin, but were added as they were, and Example 1 was used except that the matrix resin of Preparation Example 3 prepared at the mixing ratio shown in Table 2 was used. In the same manner as above, molten matrix resin was supplied to the impregnation die, and the supply stability of the matrix resin was observed.

[0054] [Comparative Example 2]

Antioxidant C was not added as a masterbatch, but added directly to polypropylene resin A as the base resin, and Example 2 was used except that the matrix resin of Preparation Example 4 prepared at the mixing ratio shown in Table 2 was used. Similarly, the supply stability of the matrix resin was observed.

[0055] [Table 1]

[0056] [Table 2]

Formulation Example Formulation Example Formulation Example Formulation Example

1 2 3 4 Master / Without presence Yes Yes No No Polypropylene resin A

80.95 96.00 95.24 99.00 (Base resin)

Polypropylene resin B "14.29 3.00 ― ― In matrix resin

Antioxidant A * ¹ 3.33 ― 3.33 ― solid content

(Mass%)

Antioxidant B "1.43 * ¹ 0.33 1.43 0.33 Antioxidant C-" 0.67-0.67

By single screw extruder

Maruti 7s resin supply stability o O X Δ

* ¹ Used as a masterbatch with 25% by mass additive content after being melted in polypropylene resin B

[0057] From the above results, Example 1 in which an anti-oxidation agent containing an anti-oxidation agent having a melting point of 125 ° C or lower was melt-dispersed in polypropylene resin and used as a master batch, and was melted as an antioxidant. An example in which an anti-oxidation agent having a point of 125 ° C or lower and an anti-oxidation agent having a melting point of more than 125 ° C were used in combination, and these anti-oxidation agents were melt-dispersed in polypropylene resin and used as a master batch. In No. 2, it was possible to stably supply the molten matrix resin to the impregnation die using a single screw extruder.

[0058] On the other hand, in Comparative Example 1 in which an anti-oxidizing agent having a melting point of 125 ° C or lower was not used as a masterbatch but was added as it was to a polypropylene resin as a base resin, the single-screw extrusion was used. The machine was unable to supply the grease to the impregnation die.

[0059] Further, as an anti-oxidation agent, an anti-oxidation agent having a melting point of 125 ° C or lower and an anti-oxidation agent having a melting point of more than 125 ° C are used in combination to form a master batch of these anti-oxidation agents. In Comparative Example 2, which was added to the polypropylene resin as the base resin as it was, the supply of the resin to the impregnation die was unstable despite the low amount of the low melting point additive. there were.

Industrial applicability

[0060] The present invention is capable of stably supplying the matrix resin to the impregnation die using a single screw extruder, and producing a long fiber reinforced polyolefin resin composition having excellent mechanical strength and durability. Applicable to manufacture well. It should be noted that the entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2005-375302 filed on December 27, 2005 are cited here as disclosure of the specification of the present invention. Incorporate.

Claims

The scope of the claims

[1] The polyolefin resin composition is plastic-melted with a single screw extruder and filled into an impregnation die, the reinforcing fibers are passed through the impregnation die, and the long fiber-reinforced polyolefin resin rod obtained is passed through a predetermined rod. In a method for producing a long fiber reinforced polyolefin resin molding material that is cut into lengths,

As the polyolefin resin composition, an additive containing a base resin composed of polyolefin resin; a master batch component (excluding polyolefin resin), a low melting point additive having a melting point of 125 ° C or lower A masterbatch obtained by previously melt-dispersing in a polyolefin resin, and a composition containing: a method for producing a long fiber reinforced polyolefin resin molding material.

[2] The method for producing a long-fiber reinforced polyolefin resin composition according to claim 1, wherein the polyolefin resin in the master batch has an MFR of 5 to 40 (g / 10 min).

[3] The method for producing a long-fiber reinforced polyolefin resin composition according to claim 1 or 2, wherein the polyolefin resin of the base resin has an MFR force of 0 to 200 (g / 10 min).

[4] The polyolefin resin of the base resin and the polyolefin resin of the masterbatch are polypropylene-based resins. The production of a long fiber reinforced polyolefin resin composition according to any one of claims 1 to 3. Method.

[5] The additive is at least selected from an antioxidant, a light stabilizer and an ultraviolet absorber.

It is 1 type, The manufacturing method of the long fiber reinforcement polyolefin resin molding material of any one of Claims 1-4.

[6] The method for producing a long fiber reinforced polyolefin resin composition according to any one of claims 1 to 5, wherein the master batch contains 15 to 50% by mass of the additive.

[7] The method for producing a long fiber reinforced polyolefin resin composition according to any one of claims 1 to 6, wherein the additive contains 30 to LOO% by mass of the low melting point additive.

[8] The long fiber reinforcement according to any one of claims 1 to 7, wherein the polyolefin resin composition contains 2 to 35 parts by mass of the master batch with respect to 100 parts by mass of the base resin. A method for producing a polyolefin resin molding material.