JP2017075290A - Manufacturing method of carbon fiber reinforced and modified polypropylene resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome current situation that a polypropylene resin does not reach large adoption because a carbon fiber is expensive and adhesive with nonpolar polypropylene is bad although the polypropylene has light specific gravity of 0.90, is excellent in molding processability, is expected to have higher strength by carbon fiber reinforcement and reduction of weight and recyclability as well as to expand applications as an ocean civil engineering material, a high rise building material, a railway vehicle material, an automobile material and other advanced materials while utilizing characteristics of more corrosion resistance than that of iron or concrete.SOLUTION: A polypropylene resin and a maleic acid compound are modified at high speed by a reaction extrusion method with organic peroxide as a catalyst and mixed with an inexpensive carbon fiber which is largely produced by a large tow method. Further a thermoplastic composite material of a carbon fiber reinforced and modified polypropylene resin is manufactured by using an epoxy resin binder and an organic acid metal catalyst for increasing reduced molecular weight and melting viscosity. Properties of the composite material with ZOLTEK made carbon fiber chip 30% (comparison with raw material polypropylene) is light weight and high rigidity with specific gravity of 1.07 (1.2 times) and flexure elastic modulus of 16 GPa (9 times).SELECTED DRAWING: None

Description

  The present invention relates to providing a method for producing a lightweight, high-strength, recyclable carbon fiber reinforced / modified polypropylene resin.

Conventionally, a polypropylene resin is a thermoplastic resin having excellent molding processability, light weight, mechanical strength, rigidity, and the like, and has been widely used as a fiber, film, plastics and the like. In particular, in the plastics field, molded products are widely used for bottles, sheets, containers, daily necessities, automobile interior materials, machine parts, electrical / electronic materials, building materials, earth and wood, various industrial products, and the like.
Polypropylene resin has been used for higher-grade applications because it has improved properties such as mechanical strength and heat resistance by further mixing glass fiber or carbon fiber into a thermoplastic composite material. Yes. In particular, since glass fibers are inexpensive, composite materials reinforced with this are used in large quantities. On the other hand, since carbon fiber has high strength but is too expensive, it has been used only in a small amount for special applications as a composite material with ABS resin.

  In recent years, in the advanced industrial fields such as civil engineering / architecture, automobile industry, Shinkansen vehicle industry, aerospace industry, linear motor car, etc. Further improvements in performance such as corrosion resistance, electrical characteristics, heat resistance, and heat dissipation are required.

As shown in Patent Document 1, Patent Document 2 and Patent Document 3 as the previous prior invention, the present inventors adopted a reactive extrusion method for a middle molecular weight body having a carboxyl group at the terminal with a polyester resin, Depending on resin binder (also called chain extender, thickener) and catalyst, polyester can be reacted with each other to achieve high productivity with high molecular weight in a few minutes or less. The production method by the reactive extrusion method used was provided. However, although there has been a breakthrough in moldability due to an increase in the melt tension of polyester, on the other hand, with respect to the improvement of mechanical properties, the effect that was originally expected in the present invention was hardly seen.
In addition, as shown in Patent Document 4 and Patent Document 5, the present inventor recovered polyethylene fiber terephthalate (PET) with 15% and 30% by weight of 6 mm long recovered carbon fiber and epoxy resin binder (chain extender) and In the presence of a catalyst, the reaction is carried out by a reactive extrusion method using a twin screw extruder to obtain a recovered carbon fiber reinforced / modified pet resin, which has a mechanical strength of about 2 to 2.4 times in tensile strength and flexural elasticity. The rate has greatly improved from about 4 times to 6.8 times. In addition, in the patent document 6, the present inventor uses an inexpensive new carbon fiber 6 mm long (manufactured by ZOLTEK) made of large tow PAN-based rayon, and similarly uses ZOLTEK carbon fiber reinforced / modified pet. Resins are used, and their mechanical strength is further greatly improved from about 3 to 4 times in tensile strength and from about 6 to 10 times in flexural modulus.
However, it has been pointed out that the pet resin has a specific gravity of 1.35, which is about 40% heavier than the specific gravity of polypropylene of 0.90.

Notice No. 3503952 International Publication WO2009 / 004745 A1 US 8258239B2 registration Japanese Patent Application No. 2014-179595 Japanese Patent Application No. 2014-225597 Japanese Patent Application No. 2015-024685

Problems to be solved by the invention

  Corrosion resistance and electrical conductivity, including further weight reduction and energy saving by improving mechanical strength of components in advanced industrial fields such as civil engineering / architecture, automobile industry, Shinkansen vehicle industry, aerospace industry, linear motor car, etc. Further improvements in performance such as heat resistance and heat dissipation are required. In particular, the present invention is an outdoor structure by improving the strength of synthetic timber that lacks strength, lightweight materials for high-rise buildings, high strength and corrosion resistant materials for coastal expressways, corrosion resistant and high strength materials for marine structures, etc. The purpose is to develop applications such as anti-corrosion materials and automobiles.

Means to try to solve the problem

  It is an object of the present invention to provide a method for producing a carbon fiber reinforced / modified polypropylene resin that is lightweight and has improved strength. That is, the present invention produces a modified polypropylene resin by heating and mixing the polypropylenes (A) and (B), the modifiers (C) and (D), and the spreading agent (E). And a method for producing a carbon fiber reinforced polyester resin by melt-mixing with carbon fiber (F).

More specifically, the present invention provides the following production method.
The present invention includes (A) 100 parts by weight of a polypropylene resin, (B) 10-30 parts by weight of a polypropylene powder resin, (C) 0.1-3 parts by weight of an organic unsaturated acid compound, (D) After reacting a mixture composed of 0.01 to 0.50 parts by weight of an organic peroxide and (E) 0.01 to 1 part by weight of a spreading agent at a temperature equal to or higher than the melting point of polypropylene by a reactive extrusion method, (F) Carbon fiber characterized in that MFR (230 ° C., load 2.16 Kg) based on JIS-K7210 method is 1 to 40 g / 10 min by melting and mixing with 5 to 150 parts by weight of carbon fiber. A method for producing a reinforced / modified polypropylene resin is provided.

The present invention secondly includes (A) 100 parts by weight of a polypropylene resin, (B) 10-30 parts by weight of a polypropylene powder resin, (C) 0.1-3 parts by weight of an organic unsaturated acid compound, (D) After reacting a mixture composed of 0.01 to 0.50 parts by weight of an organic peroxide and (E) 0.01 to 1 part by weight of a spreading agent at a temperature equal to or higher than the melting point of polypropylene by a reactive extrusion method, (F) 5 to 150 parts by weight of carbon fiber and (G) a polyfunctional epoxy compound having two or more epoxy groups in the molecule and having a weight average molecular weight of 2.000 to 10,000. MI (230 ° C., load 2.16 Kg) based on JIS-K7210 method is reduced to 0 by mixing 0.1 to 2 parts by weight of binder and 0.01 to 1 part by weight of (H) binding reaction catalyst. .5-10 g / 10 min There is provided a method of producing a carbon fiber-reinforced-modified polypropylene resin, characterized.

In the present invention, thirdly, the polypropylene resin (A) and the polypropylene powder resin (B) have an MI (230 ° C., load 2.16 Kg) in accordance with JIS-K7210 method of 0.5 to 10 g / 10 minutes, one or more selected from the group consisting of polypropylene homopolymer, polypropylene / ethylene block copolymer, polypropylene / ethylene random copolymer, polypropylene / ethylene super random copolymer, or recycled products of these recovered molded articles The method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 1 or 2 is provided.

4thly, the said organic unsaturated acid compound (C) contains maleic anhydride, The manufacturing method of the carbon fiber reinforced and modified polypropylene resin of Claim 1 or 2 characterized by the above-mentioned. It is to provide.

  5. The method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 1, wherein the organic peroxide (D) contains cumyl diperoxide. 5. Is to provide.

  The present invention sixthly provides the method for producing a carbon fiber-reinforced / modified polypropylene resin according to claim 1 or 2, wherein the spreading agent (E) contains liquid paraffin. It is.

  In the present invention, seventhly, the carbon fiber (F) has a number of filaments of 50,000 or more, a specific gravity of 1.5-2.2, a fiber diameter of 7-18 μm, a tensile strength of 580-4,200 MPa, and a tensile modulus. The carbon according to claim 1, comprising carbon fiber having 35 to 250 GPa, elongation of 0.3 to 3%, carbon content of 95% or more, and produced at a high speed by a large tow system. A method for producing a fiber-reinforced / modified polypropylene resin is provided.

  In the present invention, eighthly, the binder (G) has a polyfunctional epoxy compound having two or more epoxy groups in the molecule and a weight average molecular weight of 2.000 to 10,000. The method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 2, comprising:

  In the present invention, eighthly, the binding reaction catalyst (H) is an alkali metal carboxylate, an alkaline earth metal carboxylate, an alkali metal carbonate or hydrogen carbonate, or an alkaline earth metal carbonate. The method for producing a carbon fiber-reinforced / modified polypropylene resin according to claim 2, comprising at least one selected from the group consisting of a salt or a bicarbonate.

Effect of the invention

  According to the present invention, by modifying a polypropylene resin with a modifier (catalyst of an unsaturated organic acid compound and an organic peroxide), the adhesion with carbon fiber, which has been difficult in the past, is epoch-making. And improved the mechanical strength of the composite. Furthermore, it has been demonstrated that a composite made of a large tow type carbon fiber (ZOLTEK chop), which is undergoing mass production and cost reduction, and a modified polypropylene resin can be mass-produced by a reactive extrusion method. This new material is lightweight, strong and recyclable, and is expected to be used in a huge market for future automotive applications with further improvements. Excellent physical properties such as corrosion resistance, heat resistance, heat transfer, conductivity, oil resistance, and weather resistance. In addition, currently recovered carbon fibers by-produced at the time of assembling the aircraft and recycled carbon fibers from a carbon fiber reinforced epoxy resin composite material when a large amount of future aircraft body is expected to be scrapped can be used.

Hereinafter, the present invention will be described in detail.
[(A) component polypropylene resin]
The polypropylene resin of the component (A) as a main raw material in the present invention is a polypropylene homopolymer, a polypropylene / ethylene block copolymer, a polypropylene / ethylene random copolymer, a polypropylene / ethylene superrandom copolymer, or a recycled product of a recovered molded product thereof. Circulating products can be used. If a strong carbon fiber reinforced composite is desired, a polypropylene homopolymer is selected. If a carbon fiber reinforced composite with high impact strength is desired, a polypropylene block copolymer is selected. In the present invention, since the molecular weight is lowered by molecular cleavage due to the catalytic action of the organic peroxide of component D, it is preferable to select a grade having a large molecular weight and a small MI as the main raw material. That is, it is preferable that MI (230 degreeC, load 2.16Kg) based on JIS-K7210 method is 0.5-10 g / 10min. A hollow molding grade is preferable, and the blending amount of the main raw material is 100 parts by weight.

[(B) Component Polypropylene Powder Resin]
Component (B) is an auxiliary that uniformly disperses 0.1 to 3 parts by weight of the organic unsaturated acid compound of component (C) and 0.01 to 0.50 parts by weight of organic peroxide of component (D). As a role. Polypropylene homopolymer, polypropylene / ethylene block copolymer, polypropylene / ethylene random copolymer, polypropylene / ethylene super random copolymer, or a recycled product of these recovered molded articles can be used in a powder state. MI is also preferably 0.5 to 10 g / 10 min. The amount of the auxiliary material is 10-30 parts by weight.

[Organic unsaturated acid compound of component (C)]
As the component (C), maleic anhydride and derivatives thereof can be used, but maleic anhydride is preferable. Its role is to react when the organic peroxide of component (D) attacks the polypropylene to generate radicals in the molecular chain, and stops by giving a carboxyl group to the polypropylene, thereby modifying the originally nonpolar polypropylene. There is. The amount is 0.1 to 3 parts by weight, preferably 0.2 to 1 part by weight. If the amount is 0.1 parts by weight or less, the modification effect of the polypropylene resin is insufficient. If the amount exceeds 3 parts by weight, unreacted substances remain during reaction extrusion and volatilize to cause damage to the human body.

[Organic peroxide of component (D)]
The component (D) organic peroxide can be used as a resin melt flow modifier, maleating agent, and grafting agent, such as Perhexa Series (HC, C, 22, 25B) from NOF Corporation. Etc.), perbutyl series (C, D, P etc.), park mill series (D etc.) can be used. Commercially available dicumyl diperoxide (manufactured by Aldrich) could be suitably used.
The amount is 0.01 to 0.50 parts by weight. If the amount is 0.01 parts by weight or less, the modification effect of the polypropylene resin is insufficient. If it is 0.50 part by weight or more, the lowering of the molecular weight of the polypropylene resin proceeds excessively.

[(E) Component spreading agent]
The component (E) has a role of 0.1 to 3 parts by weight of a fine powder of the organic unsaturated acid compound (C) and a fine powder of the organic peroxide 0.01 to 0 as the component (D). .50 parts by weight have a role of uniformly adhering to the surface of the component (B) polypropylene powder resin. Liquid paraffin is preferred. Paraffin oil and petroleum wax can also be used. A compounding quantity is 0.01-1 weight part.

[Carbon fiber of component (F)]
It is preferable to use a high-strength PAN-based industrial product as the (F) component carbon fiber in the present invention. The top priority candidate is an inexpensive carbon fiber chop that can be mass-produced by high-speed firing of large tow (LT: 50,000 filaments) manufactured by ZOLTEK, USA (LT-PAN-based carbon fiber “Panex35” manufactured by ZOLTEK, USA, 6 mm long) Is particularly preferred. As a second priority, Toray Corp.'s high-performance carbon fiber “Torayca” T500, T600, and T700 series for aircraft aircraft can also be used. Also, industrial use cut fibers T008 series, T010 series, and TS12-006 (cut length 3-12 mm) can be used as raw materials, but they are expensive. On the other hand, “Torayca” milled fiber MLD series (fiber length 30-150 μm) can also be used as a raw material, but the strength of the composite material is small. On the other hand, these carbon fiber industrial products generally have a relatively high carboxyl group content.
As a third priority, pitch-based carbon fiber industrial products of Kureha Co., Ltd. and Osaka Gas Chemical Co., Ltd. can also be used. These have a relatively high content of functional groups, but have a considerably low strength. Since the strength of the molded product has an isotropic advantage, it can be preferably used in the precision molding field.
Table 1 shows the specifications of carbon fibers of typical industrial products in comparison with glass fibers. If carbon fiber can be reduced in cost by mass production, it can be assumed that the advantages of weight reduction, high strength, and recyclability can be greatly exhibited compared to cheap glass fiber.

[Binder for component (G)]
The binder of the component (G) of the present invention preferably has a weight average molecular weight of 1,000 to 300,000, and a polymer type polyfunctional epoxy compound containing 2 to 100 epoxy groups in the molecule. Can be used alone or as a mixture of two or more. A product in which a glycidyl group containing an epoxy ring is suspended in a resin that forms a high molecular weight skeleton in a pendant form, or a product containing an epoxy group in the molecule, such as NOF's "Murproof" series, BASF Japan Co., Ltd.'s “John Krill ADR” series can be used.
The compounding quantity of the polyfunctional epoxy compound of (G) component is 0.1-5 weight part with respect to 100 weight part of polyester of (A) component. It varies greatly depending on the type and amount of carbon fiber that has a thickening effect on component (B) .In general, the effect of increasing molecular weight and melt viscosity is insufficient at less than 0.1 part by weight. Therefore, the molding processability is also insufficient and the basic physical properties and mechanical properties of the molded product are inferior.On the other hand, if it exceeds 2 parts by weight, the molding processability deteriorates, and the yellowing / coloring of the resin and the gel or fish Eye (FE) is a by-product.

[(H) Component Binding Reaction Catalyst]
The coupling reaction catalyst as the component (H) in the present invention includes (1) alkali metal organic acid salts, carbonates and hydrogen carbonates, and (2) alkaline earth metal organic acid salts, carbonates and hydrogen carbonates. A catalyst containing at least one selected from the group consisting of: As the organic acid salt, carboxylate, acetate and the like can be used, but stearates are particularly preferable among the carboxylates. The metal that forms the metal salt of the carboxylic acid can be an alkali metal such as lithium, sodium and potassium; an alkaline earth metal such as magnesium, calcium, strontium and barium.
The compounding amount of the carboxylate as the binding reaction catalyst is 0.01 to 1 part by weight with respect to 100 parts by weight of the component (A) polypropylene. In particular, the amount is preferably 0.1 to 0.5 part by weight. If the amount is less than 0.01 parts by weight, the catalytic effect is small, the copolymerization reaction is not achieved, and the molecular weight may not be sufficiently increased. If the amount exceeds 1 part by weight, problems such as gel generation due to local reactions and troubles in the extruder due to rapid increase in melt viscosity due to acceleration of hydrolysis are caused.

[Formulation method, reactive extrusion method]
Next, a method for blending the polypropylene resin of the present invention will be described. Each component is mixed with a mixer such as a tumbler or a Henschel mixer, and then supplied to the extrusion apparatus as a top feed method. The heating and melting temperature is desirably 220 ° C. to 240 ° C. above the melting point of polypropylene from the viewpoint of the reactive extrusion method. In particular, it is preferably 250 ° C. or lower, particularly preferably 230 ° C. If the temperature exceeds 250 ° C., the surface treatment agent or sizing agent of the carbon fiber may change, and the discoloration or thermal decomposition of polypropylene may occur.
In addition to the above simultaneous mixing method, as a side feed method, a mixture of (A) polypropylene, (B) component, (C) component, and (D) component is supplied to a twin-screw extruder while performing reactive extrusion. The composite material can be produced by preventing the carbon fiber from being cut by injecting the carbon fiber of the component (F) into the outlet portion of the twin-screw extruder. Suitable when the carbon fiber is chopped.
As the reactive extrusion apparatus, a single screw extruder, a twin screw extruder, a two-stage extruder of a combination thereof, or the like can be used. Single screw extruders are inexpensive and are suitable when the carbon fiber is powdery or short. The twin screw extruder is expensive, but is suitable for side-feeding chopped carbon fibers.

As an application example of the high-strength and lightweight composite of the present invention, for the time being, residential outdoor deck materials and offshore construction materials are assumed. In particular, the outdoor deck materials for houses in the US and Europe reach 2.6 million tons per year. Traditionally, it has relied on natural timber, but there is no prospect of recovery in the face of depletion of South and South American wood resources. Currently, wood flour / polyethylene and wood flour / polypropylene synthetic wood are used. However, compared to the high strength of natural wood (flexural modulus 6-14 GPa), the strength of synthetic wood of wood flour / polyethylene (1-3 GPa) and wood flour / polypropylene (about 5 GPa) is too weak. However, the synthetic wood market in North America is about 690,000 tons (2013), with wood flour / polyethylene 83%, wood flour / polypropylene 9%, wood flour / vinyl chloride 7%, and others 1%.
The carbon fiber reinforced / modified polypropylene resin of the present invention has a high strength of a solid molded body (ZOLTEK 30% and a flexural modulus of 16 GPa), so that an increase in strength due to addition to synthetic wood is expected.

Next, the present invention will be described in detail based on examples. Evaluation methods for the polypropylene and the carbon fiber reinforced / modified polypropylene resin of the present invention are as follows.
(1) Measurement method of melt index (MI) According to the conditions of JIS K7210 (ISO 1133, ASTM D 1238), the measurement was performed under the conditions of a temperature of 230 ° C. and a load of 2.16 kg. However, the resin used was previously dried in hot air or vacuum at 80 ° C. for 2 hours. Or, the manufacturer's catalog value was adopted.
(2) Measuring method of specific gravity According to JIS K7112 method A (submerged in water method), resin pellets or small pieces of molded articles were measured as alcohol as a liquid. Or it measured also by the dimension measuring method of JISK7222.
(3) Measuring method of mechanical strength (1) When the prototype pellet was a small amount of 1 kg or less, a small test piece was prepared and carried out.
For example, using an injection molding machine SE18DUZ manufactured by Sumitomo Heavy Industries, Ltd. (with a clamping pressure of 18 tons and a screw diameter of 16 mm), the molding temperature is 270 ° C., the mold temperature is 35 ° C., and the cooling time is 15-20 seconds. Molded.
Shape of test piece: Tensile test piece JIS K7162 5A type (thickness 2 mm)
Bending specimen strip type 80mm x 10mm (thickness 4mm)
(2) When a large amount of prototype pellets (3 kg or more), a multi-purpose test piece was prepared and carried out.
Shape of test piece: ISO 20753, JIS K7139 A1 type
Length 120mm, thickness 4mm, chuck width 20mm, constriction width 10mm, length 80mm (Z runner method)
Tensile test: The tensile strength was measured at a test speed of 2 mm / min, and evaluated by an average value of 3-5 points. Young's modulus was calculated by linear regression of 25% and 75% of the maximum load (JIS K7073 and others).
Bending test: The bending strength was evaluated by an average value of 3 to 5 points by carrying out 3 point bending at a test speed of 5 mm / min. The flexural modulus was calculated by linear regression of 25% and 75% of the maximum load (JIS K7074 et al.).
(4) Measuring method of amount of acidic functional group and amount of carboxyl group of carbon fiber Measurement was performed by Boehm method according to JIS K 0070. Sodium hydroxide and sodium hydrogen carbonate were individually added to the carbon fiber samples, and back titration was performed using a hydrochloric acid solution using an automatic potentiometer. Total acidic functional group amount (total acid amount) was measured by back titration with hydrochloric acid solution after addition of sodium hydroxide, and strong acidic functional group amount (carboxyl group amount) was measured by back titration with hydrochloric acid solution after addition of sodium bicarbonate. . The weakly acidic functional group amount (phenolic hydroxyl group amount) was determined from the total acid amount-carboxyl group amount.

  The main constituent elements of the present invention, (A) and (B) component polypropylene, and (F) component carbon fiber contain acidic functional groups and carboxyl groups in order to improve their adhesion and increase strength. It is preferable to make it. Carbon fibers contain acidic functional groups and carboxyl groups, though large and small.

Analysis example 1

カルボキシル基は、新品炭素繊維には極めて微量にしか存在しないが、約５００℃焼成後の再生炭素繊維には０．０３−０．０５ｍｍｏｌ／ｇも存在し、電解酸化後の再生炭素繊維にはその２−３倍の０．１０ｍｍｏｌ／ｇ にまで増加していた。Analysis of acidic functional group and carboxyl group of component (F) carbon fiber 1 g of carbon fiber is weighed in each 200 cc Erlenmeyer flask and immersed in 50 mL of 0.1 mol / L sodium hydroxide aqueous solution or sodium hydrogen carbonate aqueous solution. It was. After plugging, the two bodies were put on a permeator for 24 hours. The supernatant of each container (5 mL) was titrated with 0.05 mol / L hydrochloric acid aqueous solution to identify the total acid amount and the carboxyl group amount. The analysis based on the Boehm method was also performed on the regenerated carbon fiber and the new carbon fiber after firing, and the results are compared and shown below.

Carboxyl groups are present in a very small amount in new carbon fibers, but 0.03-0.05 mmol / g is present in regenerated carbon fibers after firing at about 500 ° C., and in regenerated carbon fibers after electrolytic oxidation, It increased to 0.10 mmol / g 2 to 3 times that.

[Production Examples of Modified Polypropylene Resin P1, P2, P3 and P4]
[Production Example 1] Polypropylene homopolymer pellets (hollow grade, MI 0.5: flexural modulus 1.8 GPa, Charpy impact strength 9.0 KJ / m ² ) 100 parts by weight as component A, polypropylene / powder as component B 20 parts by weight (manufactured by Sun Allomer Co., Ltd., MI 0.3), 1 part by weight of maleic anhydride (reagent grade 1) as C component, 0.100 part by weight of dicumyl peroxide (manufactured by ALDLICH) as D component, As an E component, 0.2 part by weight of liquid paraffin was used.
First, polypropylene powder P was charged into a tumbler, and then liquid paraffin E was added and stirred for 5 minutes, and then finely pulverized dicumyl peroxide D was added and stirred for another 5 minutes. Then, finely pulverized maleic anhydride C was added and stirred for another 5 minutes. Finally, the polypropylene homopolymer pellet A was added and stirred for 10 minutes for uniform mixing.
Using a single-screw extruder (65 mm diameter, L / D30, modified / single vent type, modified / compressed screw) manufactured by Toshiba Machine Co., Ltd., set the cylinder and die set temperature consisting of 7 blocks of this extruder. It was set to 170-280 degreeC. The modified polypropylene resin P1 is manufactured by putting the mixed composition of the above-mentioned A, B, C, D and E components into a raw material supply hopper, extruding while measuring with a capacity-type measuring feeder and performing reactive extrusion. did. The resin temperature was 244 ° C. and the resin pressure was 10 MPa.
The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm, and cut with a rotary cutter to produce about 20 kg of translucent white resin pellets P1. The strand from the mold outlet to the water basin was bow-shaped and the melt tension was very low. The pellet shape was cylindrical and had a diameter of about 2.5 mm and a length of about 3 mm.

  [Production Example 2] The component A polypropylene / homopolymer pellets, component B polypropylene / powder, component C maleic anhydride and component E liquid paraffin are the same and in the same ratio, but the component D The modified polypropylene resin P2 was produced under the same conditions as in Production Example 1, with only the ratio of the mill peroxide being halved to 0.050 part by weight. The resin temperature was 241 ° C. and the resin pressure was 16 MPa. The strand was continuously extruded into water from a diagonally downward nozzle having a diameter of 3 mm, and cut with a rotary cutter to produce about 20 kg of translucent white resin pellets P2. The strand from the mold outlet to the basin was almost linear, and the melt tension was fairly maintained. The pellet shape was cylindrical and had a diameter of about 2.5 mm and a length of about 3 mm.

  [Production Example 3] The component A polypropylene / homopolymer pellets, component B polypropylene / powder, and component E liquid paraffin are the same and in the same ratio, but the ratio of component C maleic anhydride is 2. The modified polypropylene resin P3 was produced under the same conditions as in Production Example 1, with the ratio of the D component dicumyl peroxide being 0.075 parts by weight and intermediate between Production Examples 1 and 2. . The resin temperature was 238 ° C. and the resin pressure was 14 MPa. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm and cut with a rotary cutter to produce about 20 kg of translucent white resin pellets P3. The strand from the mold outlet to the basin was somewhat bowed and melt tension was considerably reduced, but the water-cooled strand was significantly improved by double addition of maleic anhydride, unlike unmodified polypropylene. It was. The pellet shape was cylindrical and had a diameter of about 2.5 mm and a length of about 3 mm.

[Production Example 4] Polypropylene block copolymer pellets as the A component (hollow grade, MI 0.7: flexural modulus 1.1 GPa, Charpy impact strength 91 KJ / m ² ) 100 parts by weight, B component as the polypropylene powder (Sun Aroma) Manufactured by Co., Ltd., MI 0.3) 20 parts by weight, maleic anhydride (reagent grade 1) 2 parts by weight as C component, dicumyl peroxide 0.075 parts by weight as D component, liquid paraffin 0.2 as E component Part by weight was used.
The modified polypropylene resin P4 was produced under the same conditions as in Production Example 1. The resin temperature was 238 ° C. and the resin pressure was 16 MPa. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm and cut with a rotary cutter to produce about 20 kg of translucent white resin pellets P4. The strand from the mold outlet to the basin is slightly bowed and melt tension is considerably reduced, but the water-cooled strand is significantly improved in water-retaining properties due to the double addition of maleic anhydride, unlike unmodified polypropylene. It was done. The pellet shape was cylindrical and had a diameter of about 2.5 mm and a length of about 3 mm.

[Production Example of Carbon Fiber Reinforced / Modified Polypropylene Resin Pellets ZP1-4 Consisting of Modified Polypropylene Resin P1-P4 and ZOLTEK Carbon Fiber Chop 23%]
PAN-based carbon fiber “Panex 35” (6 mm long chop: manufactured from Large Tow with 50,000 filaments. Specific gravity 1.81, tensile strength 4,137 MPa, tensile modulus 242 GPa, elongation at break Degree 1.5%) was selected.
[Production Example 5] In order to top feed the raw material composition, it was uniformly blended in advance by the following operation. In a polyethylene bag, 300 g (23.1%) of ZOLTEK 6 mm chop was put, and 3 g of liquid paraffin was added to wet the surface. Next, 200 g of polypropylene powder was added and mixed. Finally, 800 g of modified polypropylene pellets P1 (on the other hand, in the case of Comparative Example 1, only polypropylene homopolymer pellets) were added and mixed uniformly.
Using the same-direction twin screw extruder (caliber 15 mm, L / D30, 1 vent type) manufactured by Technobel Co., Ltd., the cylinder and die temperatures of 160 to 280 ° C. and screw rotation It was set to several 150-200 rpm. The above composition was put into a hopper and stably supplied to an extrusion apparatus using a capacity-type weighing feeder. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm and cut with a rotary cutter to produce about 1.2 kg of black resin pellets ZP1. The resin pressure was 0.2 MPa, which was slightly low. The strand from the mold outlet to the water basin was thick but bowed downward, and the melt tension tended to decrease slightly. The shape of the pellet was cylindrical and had a diameter of about 2.5 mm and a length of about 3 mm. Moreover, MFR (230 degreeC, load 2.16Kg) was 23 g / 10min. Suitable for injection molding grade

  [Production Example 6] The same operation as in Production Example 5 was performed. However, 800 g of modified polypropylene pellets P2 was used. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm, and cut with a rotary cutter to produce about 1.2 kg of black resin pellets ZP2. The resin pressure doubled to 0.4 MPa. The strand from the mold outlet to the water basin was linear and had a slightly high melt tension. Moreover, MFR (230 degreeC, load 2.16Kg) is 9.8g / 10min, and is suitable for extrusion molding.

  [Production Example 7] The same operation as in Production Example 5 was performed. However, 800 g of modified polypropylene pellets P3 was used. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm, and cut with a rotary cutter to produce about 1.2 kg of black resin pellets ZP3. The resin pressure was 0.3 MPa. The strand from the mold outlet to the water basin was slightly bowed downward and the melt tension tended to be slightly lower. Moreover, MFR (230 degreeC, load 2.16Kg) is 16 g / 10min, and is suitable for injection molding.

[Production Example 8] The same operation as in Production Example 5 was performed. However, 800 g of modified polypropylene pellets P4 was used. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm, and cut with a rotary cutter to produce about 1.2 kg of black resin pellets ZP3. The resin pressure was 0.3 MPa. The strand from the mold outlet to the basin was almost linear and the melt tension was almost good. Moreover, MFR (230 degreeC, load 2.16Kg) is 11 g / 10min, and is suitable for injection molding.
The results of Example 2 are summarized in Table 2.

[Physical property evaluation of carbon fiber reinforced / modified polypropylene resin pellets ZP1-4 consisting of modified polypropylene resins P1-P4 and ZOLTEK carbon fiber chops 23%]
The physical properties of the carbon fiber reinforced / modified polypropylene resin pellets ZP1-4 produced in Example 2 were evaluated together with Comparative Examples 1 and 2. A flat plate (4 mm thickness × 20 cm square) was molded from each pellet by a hot pressing method at 230 ° C. × 7 minutes using a 4.2 mm × 20 cm square sbaser and a hydraulic hot press.
The sheet was cut to a width of 10 mm with an electric saw and various evaluation tests were performed. The results are shown in Table 3. ZP1 of Production Example 5 demonstrated the highest mechanical strength value. That is, the tensile strength 71 MPa of ZP1 is 3.2 times that of the blend of Comparative Example 1 and 2.5 times that of the polypropylene homopolymer of Comparative Example 2. The flexural modulus of 8.5 GPa is 3.1 times that of the blend of Comparative Example 1 and 7.1 times that of the polypropylene homopolymer of Comparative Example 2. The other ZP2, ZP3 and ZP4 also showed superior physical properties compared to the blend of Comparative Example 1 and the polypropylene homopolymer of Comparative Example 2.

Comparative Example 1

  A blend of ZOLTEK carbon fiber (23.1%) and polypropylene homopolymer was produced in substantially the same manner as in Production Example 5 of Example 2. In a polyethylene bag, 300 g (23.1%) of ZOLTEK 6 mm chop was put, and 3 g of liquid paraffin was added to wet the surface. Next, 200 g of polypropylene powder was added and mixed. Finally, 800 g of polypropylene homopolymer pellets (the same as in Production Example 1 of Example 1) were added and mixed uniformly. It knead | mixed with the twin-screw extruder by substantially the same operation. In the same manner as in Example 3, a hot press plate (4 mm thick × 20 cm square) was molded and a physical property test was performed.

Comparative Example 2

  Polypropylene homopolymer pellets (the same as in Production Example 1 of Example 1) were used, using a 4.2 mm x 20 cm square baser and a hydraulic heat press machine, and a hot press plate (4 mm thickness x 20 cm square) Molded. At 220 ° C. × 7 minutes, bubbles remained in a part of the translucent milky white plate, and therefore, the test was performed at 230 ° C. × 7 minutes. The physical property test was conducted in the same manner as in Example 3.

[Production and Evaluation of Carbon Fiber Reinforced / Modified Polypropylene Resin Pellets NZP1-4 Mixed with Modified Polypropylene Resin P1-P4 with 30% ZOLTEK Carbon Fiber Chop by Side Feed Method]
[Production Example 9-12] Using the same direction twin screw extruder (35 mm diameter, L / D30: modified with side feeder) manufactured by Hitachi Zosen Corporation, cylinder and die comprising 8 blocks of this extruder Were set to 150 to 260 ° C. and the screw rotation speed to 150 rpm. Using a capacity-type weighing feeder, the modified polypropylene resin pellets P1-P4 were extruded from the first hopper in each case, and the ZOLTEK carbon fiber chop was extruded from the second hopper at a rate that the carbon fiber content was 30%. Side fed continuously.
The strand was continuously extruded into water from a diagonally downward nozzle having a diameter of 3 mm and cut with a rotary cutter to produce about 5 kg of black resin pellets in each case. The strand from the mold outlet to the basin was almost linear, and the melt tension increased. The shape was cylindrical and the diameter was about 3.4 mm × length was about 6 mm. Moreover, MFR (230 degreeC, load 2.16Kg) was 1.1-4.8 g / 10min. Both are suitable for extrusion molding.
[Example of Injection Molding Piece] This carbon fiber reinforced / modified pet resin black pellet NZP1-4 was dried with hot air at 80 ° C. for 2 hours to produce a hybrid injection molding machine FNZ140 (mold clamping pressure) manufactured by Nissei Plastic Industry Co., Ltd. 140 tons, screw diameter 40 mm), molding temperature 230 ° C., mold temperature 67-68 ° C., injection pressure 30-40 MPa, injection speed 160 mm / s, screw rotation speed 80 rpm and cooling time 15 seconds, The following injection molded body was molded.
Multi-purpose test piece shape: ISO 7139, JIS K7139 A1 type, total length 120 mm, thickness 4 mm, chuck portion width 20 mm, constriction portion width 10 mm,
Same length 80mm (Z runner method)
The four kinds of ZOITEK carbon fiber (CF 30%) reinforced / modified pet resin pellets showed good injection moldability with few burrs. The surface of the test piece was smooth. A test of mechanical strength at a tensile speed of 2 mm / min and a bending speed of 5 mm / min was performed. Table 4 shows the physical property values of the pellets.
In this example 4, the side feed method of ZOLTEK 30% has few carbon fiber cracks, and the carbon fiber is easily aligned in the injection molded piece. Therefore, the top feed method of ZOLTEK 23% of Example 2-3 is used. Compared to the case where there were many cracks and it was difficult to align the carbon fibers on the hot press plate, the mechanical strength was observed to be large.
NZP1 of Preparation Example 9 demonstrated even higher maximum mechanical strength values. That is, the tensile strength of 94 MPa of NZP1 is 2.4 times that of the blend of Comparative Example 3 and 3.1 times that of the polypropylene homopolymer of Comparative Example 1. The flexural modulus 15.8 GPa is 1.1 times that of the blend of Comparative Example 3 and 13.2 times that of the polypropylene homopolymer of Comparative Example 2. The other NZP2, NZP3 and NZP4 also showed superior physical properties compared to the blend of Comparative Example 3 and the polypropylene homopolymer of Comparative Example 2. In addition, the fishing body reel body was formed in 30 consecutive shots.

In this example, the modified polypropylene and the carbon fiber composite material were separately manufactured off-line, but in an extruder with a side feeder, continuous production can be performed in-line.

Comparative Example 3

  A blend of ZOLTEK carbon fiber (30%) and polypropylene homopolymer was produced by the side feed method in substantially the same manner as in Production Example 9-12 of Example 4. However, an equal amount of mixed pellets of recycled polypropylene homopolymer (MI 1.5) and polypropylene homopolymer (MI 30: Novatec) was used. Moreover, the injection test piece was produced in substantially the same operation, and tests, such as mechanical evaluation, were implemented.

[Production Examples and Evaluation of High Viscosity / Carbon Fiber Reinforced / Modified Polypropylene Resin Pellets VZP1-4 Consisting of Modified Polypropylene Resin P1-P4, ZOLTEK Carbon Fiber Chop 23%, and Modifier]
The molecular weight of the modified polypropylene resin is reduced by the addition of an organic peroxide. However, since the reacted maleic acid is chemically bonded and contains a carboxyl group, an example in which a special epoxy compound and a catalyst are added and the molecular weight and melt viscosity are increased by a reactive extrusion method is shown. For example, the injection grade can be upgraded to an extrusion grade or a foam grade.
[Production Examples 13-16] In the same manner as in Example 1, in order to top-feed the raw material composition, it was uniformly blended by the following operation in advance. In a polyethylene bag, 150 g (23.1%) of ZOLTEK 6 mm chop was put, and 1.5 g of liquid paraffin was added to wet the surface. Next, 100 g of polypropylene powder was added and mixed. Furthermore, 0.75-3 g of thickener was added and stirred. Finally, 400 g of modified polypropylene pellets P1-P4 were added and mixed uniformly.
Using the same-direction twin-screw extruder (caliber 15 mm, L / D30, 1 vent type) manufactured by Technobel Co., Ltd., the temperature of the cylinder and die consisting of 4 blocks of this extruder was 160-280 ° C and the screw rotation speed Set to 150-200 rpm. The above composition was put into a hopper and stably supplied to an extrusion apparatus using a capacity-type weighing feeder. The strand was continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm and cut with a rotary cutter to produce about 500 g of black resin pellets VZP1-VZP4. The resin pressure increased to 0.6-0.8 MPa. The strand from the mold exit into the basin was almost linear and the melt tension increased considerably. MFR (230 degreeC, load 2.16Kg) was 2.4-12 g / 10min. Suitable for extrusion grade
The results of Example 5 are summarized in Table 5.

[Physical property evaluation of high viscosity, carbon fiber reinforced / modified polypropylene resin pellets VZP1-4]
The physical properties of the carbon fiber reinforced / modified polypropylene resin pellets ZP1-4 were evaluated in the same manner as in Example 3. Each pellet was formed into a flat plate (4 mm thickness × 20 cm square) by a hot press method of 230 ° C. × 7 minutes using a 4.2 mm × 20 cm square sbaser and a hydraulic hot press.
The sheet was cut to a width of 10 mm with an electric saw and various evaluation tests were performed. The results are shown in Table 6. VZP2 of Production Example 14 demonstrated the highest mechanical strength value. That is, the flexural modulus 5.7 GPa is 1.6 times that of the blend of Comparative Example 1 and 4.8 times that of the polypropylene homopolymer of Comparative Example 2. The other VZP2, VZP3 and VZP4 also showed superior physical properties compared to the blend of Comparative Example 1 and the polypropylene homopolymer of Comparative Example 2. In particular, VZP4 of Production Example 16 uses polypropylene block polymer as a raw material, so its strength is generally smaller than that of homopolymer, but Charpy impact strength of 7.3 KJ / m ² is 1 of the blend of Comparative Example 1 2 times, 6 times that of the polypropylene homopolymer of Comparative Example 2. Suitable for molding large containers.

According to the present invention, by modifying a polypropylene resin with a modifier (catalyst of unsaturated organic acid compound and organic peroxide), the adhesion to carbon fiber, which has been difficult in the past, has been dramatically improved. The mechanical strength of the composite material was also greatly improved. Furthermore, it has been demonstrated that a composite made of a large tow type carbon fiber (ZOLTEK chop), which is undergoing mass production and cost reduction, and a modified polypropylene resin can be mass-produced by a reactive extrusion method. This new material is lightweight, strong and recyclable. Excellent physical properties such as corrosion resistance, heat resistance, heat transfer, conductivity, oil resistance, and weather resistance. In the future, recycled carbon fibers from recovered carbon fibers and carbon fiber reinforced epoxy resin composites can also be used.
The present invention is intended for civil engineering and building materials for the time being. In the near future, it will be targeted for further lightening and energy-saving applications by improving the strength of interior materials and components in advanced industries such as the railway vehicle, automobile industry, Shinkansen vehicle industry, and linear motor cars. Moreover, since further performance improvements such as radio wave absorption, conductivity, heat resistance, and heat dissipation can be achieved, the applicability in this functional material field is great.

Claims (9)

(A) 100 parts by weight of polypropylene resin, (B) 10-30 parts by weight of polypropylene powder resin, (C) 0.1-3 parts by weight of organic unsaturated acid compound, (D) 0.01% of organic peroxide -0.50 parts by weight, and (E) a mixture composed of 0.01-1 part by weight of a spreading agent is reacted at a temperature equal to or higher than the melting point of polypropylene by a reactive extrusion method. A carbon fiber reinforced / modified polypropylene resin characterized in that MFR (230 ° C., load 2.16 Kg) based on JIS-K7210 method is 1 to 40 g / 10 min by melt mixing with 150 parts by weight. Production method. (A) 100 parts by weight of polypropylene resin, (B) 10-30 parts by weight of polypropylene powder resin, (C) 0.1-3 parts by weight of organic unsaturated acid compound, (D) 0.01% of organic peroxide -0.50 parts by weight, and (E) a mixture composed of 0.01-1 part by weight of a spreading agent is reacted at a temperature equal to or higher than the melting point of polypropylene by a reactive extrusion method. 0.1 to 2 binders comprising 150 parts by weight and (G) a polyfunctional epoxy compound having two or more epoxy groups in the molecule and having a weight average molecular weight of 2.000 to 10,000. MI (230 ° C., load 2.16 Kg) based on JIS-K7210 method by 0.5 to 10 g / 10 minutes by melting and mixing with parts by weight, 0.01 to 1 part by weight of (H) binding reaction catalyst Carbon characterized by Method for producing a fiber-reinforced-modified polypropylene resin.   The polypropylene resin (A) and the polypropylene powder resin (B) have an MI (230 ° C., load 2.16 kg) in accordance with the JIS-K7210 method of 0.5 to 10 g / 10 min. It is at least one selected from the group consisting of homopolymers, polypropylene / ethylene block copolymers, polypropylene / ethylene random copolymers, polypropylene / ethylene super random copolymers, or recycled products of these recovered molded articles. A method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 1.   The method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 1 or 2, wherein the organic unsaturated acid compound (C) contains maleic anhydride.   The method for producing a carbon fiber-reinforced / modified polypropylene resin according to claim 1 or 2, wherein the organic peroxide (D) contains cumyl diperoxide.   The method for producing a carbon fiber-reinforced / modified polypropylene resin according to claim 1 or 2, wherein the spreading agent (E) contains liquid paraffin.   The carbon fiber (F) has a filament number of 50,000 or more, a specific gravity of 1.5-2.2, a fiber diameter of 7-18 μm, a tensile strength of 580-4,200 MPa, a tensile elastic modulus of 35-250 GPa, and an elongation of 0. The carbon fiber-reinforced / modified polypropylene resin according to claim 1 or 2, comprising carbon fiber having a 3-3% and carbon content of 95% or more, and produced at a high speed by a large tow system. Manufacturing method.   The binder (G) contains a polyfunctional epoxy compound having two or more epoxy groups in the molecule and a weight average molecular weight of 2.000 to 10,000. A method for producing a carbon fiber reinforced / modified polypropylene resin according to claim 1 or 2.   The binding reaction catalyst (H) comprises an alkali metal carboxylate, an alkaline earth metal carboxylate, an alkali metal carbonate or hydrogen carbonate, or an alkaline earth metal carbonate or hydrogen carbonate. The method for producing a carbon fiber-reinforced / modified polypropylene resin according to claim 1, comprising at least one selected from the group.