JP2016199730A - Production method of foam-molded article of carbon fiber-reinforced modified polyester resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a novel material having a reduced weight by foaming a carbon fiber-reinforced modified PET resin having improved strength.SOLUTION: A thermoplastic composite material of a carbon fiber-reinforced modified polyester resin is obtained by kneading a polyester resin and carbon fiber while modifying terminal functional groups of the polyester by using an epoxy resin-based binder and an organic acid metal-based catalyst by a reaction extrusion method. From pellets of the composite material having improved melt viscosity and moldability, there is produced a foamed molded article to develop a new material having improved light weight and physical properties such as strength and the like.SELECTED DRAWING: None

Description

  In the present invention, the thermoplastic polyester (A), carbon fiber (B), multifunctional epoxy resin binder (C) and catalyst (D) are heated to a temperature equal to or higher than the melting point of the polyester to increase the melt viscosity. The present invention relates to providing a method for producing a foamed article of carbon fiber reinforced / modified polyester resin.

Conventional thermoplastic polyesters include, for example, polyethylene terephthalate (hereinafter referred to as PET or pet), polybutylene terephthalate (PBT), polycarbonate (PC) and the like as aromatic saturated polyesters. These have excellent physical properties such as transparency, mechanical strength and rigidity as thermoplastic resins, and are widely used as fibers, films, 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.
In addition, these polyesters have been used for higher-grade applications because they have improved properties such as mechanical strength and heat resistance by mixing glass fibers or carbon fibers into thermoplastic composites. ing. In particular, since glass fibers are inexpensive, PET composites, PBT composites, and PC composites reinforced with this are used in large quantities. On the other hand, because carbon fibers are high in strength but too expensive, these polyester composites have been used only in small amounts for special applications.

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.
Synthetic resins generally have improved moldability and physical properties if their molecular weight is increased. However, polyester is difficult to obtain, for example, a polymer having a molecular weight of 50,000 or more due to the production method being a polycondensation method. It is extremely difficult to stably produce an extruded foam molded article. In addition, the solid layer polymerization method for increasing the molecular weight of the polyester to about twice the molecular weight requires several hours, so that the productivity is low. In addition, there was a weak point that required large-scale production facilities for petrochemical complexes.

As shown in Patent Document 1, Patent Document 2 and Patent Document 3, the present inventors adopted a reactive extrusion method for a medium molecular weight body having a carboxyl group at the terminal of these polyesters, and an epoxy resin binder ( Reactive extrusion process that uses compact and inexpensive equipment that achieves high productivity by reacting polyesters and achieving high molecular weight in a short time of several minutes or less, depending on the chain extender and thickener) and catalyst. Provided a manufacturing method. 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 a thick PAN-based rayon as a raw material, and similarly ZOLTEK carbon fiber reinforced / modified pet. Resins are used, and their mechanical strength has been greatly improved from about 3 to 4 times in tensile strength and from about 6 to 10 times in flexural modulus.

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

  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-resistant enclosure and heat dissipation are required. In particular, the present invention relates to a structure outside a house by improving the strength of synthetic timber with insufficient strength, a lightening material for a high-rise building, a high strength / corrosion resistant material for a coastal expressway, a corrosion resistant / high strength material for a marine structure, The purpose is to develop applications for anti-corrosion materials such as surface flying boats.

Means to try to solve the problem

  An object of the present invention is to provide a method for producing a lightweight new material by foaming a carbon fiber reinforced / modified pet resin having improved strength. That is, the present invention has a high melt viscosity by heating and mixing thermoplastic polyester (A), carbon fiber (B), multifunctional epoxy resin binder (C) and catalyst (D). To produce a carbon fiber reinforced polyester resin having improved molding processability, and then producing a foam molded article that has been reduced in weight by a foam molding method and improved in physical properties such as mechanical strength and corrosion resistance. Is.

More specifically, the present invention provides the following production method.
The present invention first includes 100 parts by weight of the polyester as the component (A), 5 to 150 parts by weight of the carbon fiber as the component (B), and two or more epoxy groups in the molecule as a binder for the component (C). A composition composed of 0.1 to 2 parts by weight of a polyfunctional epoxy compound and 0.01 to 1 part by weight of a (D) component binding reaction catalyst is heated at a temperature equal to or higher than the melting point of the polyester to obtain a high melt viscosity. The present invention provides a method for producing a foamed article of carbon fiber reinforced / modified polyester resin, characterized in that the carbon fiber reinforced / modified polyester resin is foamed by adding a foaming agent.

  The second aspect of the present invention is that the polyester as the component (A) contains at least one of polyethylene terephthalate, polybutylene terephthalate, polycarbonate, or a recycled product of the recovered molded product thereof. Item 8. A method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to Item 1. .

  The third aspect of the present invention is that the carbon fiber of component (B) is any one or more of the group consisting of recovered short fiber or powdered carbon fiber, regenerated carbon fiber short fiber or powdered fiber The method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, comprising:

Fourthly, the carbon fiber of the component (B) is an industrial product carbon fiber short fiber or powdered fiber, an electrochemically oxidized industrial product carbon fiber short fiber or powdered fiber, or 2. The carbon fiber reinforced / modified polyester resin foam-molded article according to claim 1, comprising at least one of short fibers or powder fibers of industrially carbonized industrial products. The manufacturing method of this is provided.

The fifth aspect of the present invention is the carbon fiber-reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a volatile foaming agent and is an inert gas such as carbon dioxide and / or nitrogen gas. The manufacturing method of a foaming molding is provided.

  Sixthly, the present invention provides the method for producing a foamed molded article of carbon fiber reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a heat decomposable foaming agent. .

Claim 6

  The present invention seventhly provides the method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a hydrocarbon compound having a low boiling point. It is.

Effect of the invention

According to the present invention, a new ester bond containing a hydroxy group is first formed by a chemical reaction involving cleavage of the epoxy ring of a polyfunctional epoxy resin as a binder in the presence of a catalyst at the carboxyl group at the molecular end of the polyester. It can be made into a high molecular weight polyester resin with a high melt viscosity.
In addition, the carbon fiber reinforced / modified polyester resin of the present invention is produced at a high speed with pellets having a JIS melt flow rate (280 ° C., load 2.16 Kg) of 20 to 40 g / 10 min with few strand breaks. easy. However, in the horizontal extrusion type foaming method, if the melt viscosity is insufficient, the molding stability is not good. Therefore, in the present invention, the resin containing either the binder of component (C) and the coupling reaction catalyst of component (D) at the time of molding, or one or more of the group consisting of amorphous polyester or polyolefin is used. The manufacturing method which uses together the masterbatch which makes a base | substrate at the time of foam molding is provided. The addition amount of the masterbatch is 1 to 10 parts by weight, preferably 2 to 6 parts by weight, based on the carbon fiber reinforced polyester resin. A JIS method melt flow rate (280 ° C., load 2.16 Kg) and 0.1 to 20 g / 10 min are preferable for extrusion foam molding.
In the present invention, inexpensive industrial carbon fibers, more inexpensive recovered carbon fibers, and recycled carbon fibers from carbon fiber reinforced composites (CFRP) for aircraft end materials can be suitably used as raw materials.

Hereinafter, the present invention will be described in detail.
[Polyester of component (A)]
The polyester of component (A) as the main raw material in the present invention is an aromatic saturated polyester. Specific examples of this series of polyesters include polyethylene terephthalate (PET), low melting point PET copolymerized with a small amount of isophthalic acid, a copolymer of ethylene glycol, cyclohexanedimethanol and terephthalic acid (PETG), polytetramethylene terephthalate (poly Butylene terephthalate (PBT), polyethylene-2,6-naphthalate (PEN), and the like. Polybutylene terephthalate (PBT) is preferred. Polyethylene terephthalate (PET) that is mass-produced and extremely inexpensive is particularly preferred.
In the present invention, as the polyester of the component (A) as the main raw material, polycarbonate (PC; poly-4,4′-isopropylene diphenyl carbonate) having bisphenol A as the main raw material can be used as another series.

  PET as a representative polyester that can be used in the present invention has an intrinsic viscosity of 0.50 dl / g or more measured at 25 ° C. by dissolving in a 1,1,2,2-tetrachloroethane / phenol (1: 1) mixed solvent. (For fibers) is preferred, 0.70 dl / g or more (for sheets) is more preferred, and 0.80 dl / g or more (for bottles) is even more preferred. When the intrinsic viscosity is less than 0.50 dl / g, the bonding reaction is difficult even according to the present invention, and the obtained polyester / carbon copolymer may not always have excellent mechanical strength. The upper limit of the intrinsic viscosity is not particularly limited, but is usually 1.1 dl / g or less, preferably about 0.80 dl / g, which is mass-produced for PET bottles and relatively inexpensive. The upper limit for the availability of commercially available PET is an intrinsic viscosity of 1.25 dl / g. However, since the moldability deteriorates when used alone, the intrinsic viscosity is 0.60-0.80 dl / g in the present invention. It is preferable to use a mixture.

[Carbon fiber of component (B)]
The carbon fiber of the component (B) in the present invention preferably has an oxygen-containing functional group, particularly a carboxyl group on its surface. As the carbon fiber, it is preferable to use a PAN-based industrial product as the first series. For example, an inexpensive carbon fiber chop manufactured by ZOLTEK (USA) (a rattan (LT) PAN-based carbon fiber “Panex 35” 6 mm long manufactured by ZOLTEK, USA) is particularly preferable. Toray Industries' high-performance carbon fiber "Torayca" T500, T600, T700 series for aircraft can also be used. In addition, T008 series, T010 series, TS12-006 (cut length 3-12 mm) of cut fibers for industrial use, or MLD series (fiber length 30-150 μm) of “Torayca” milled fibers can also be used as raw materials. In general, these carbon fiber industrial products have a relatively high carboxyl group content.
Pitch-based carbon fiber industrial products of Kureha Co., Ltd. and Osaka Gas Chemical Co., Ltd. can be used as the second series. These have a relatively large functional group content, but have a slightly lower strength. Since the strength of the molded product has an isotropic advantage, it can be preferably used.

As the carbon fiber of the component (B) of the present invention, regenerated carbon fiber recovered from a carbon fiber reinforced thermosetting epoxy resin composite (CFRP) can be preferably used as a third series. Carbon fiber reinforced thermosetting epoxy resin composite (CFRP), which is the raw material, is currently milled by about 40% when milling aircraft, drill chips by-produced during boring, fishing rods, golf Obtained from tees, etc. The future is expected to be derived in large quantities from CFRP scrap, which accounts for about 65% of large aircraft bodies.
In addition, bobbin-wrapped long-fiber cut fibers (cut length: 3-12 mm) collected as semi-finished products at the time of manufacturing aircraft bodies and the like can be used satisfactorily because they are of good quality and extremely inexpensive.
Recycled carbon fiber introduces a large number of carboxyl groups by performing electrolytic oxidation treatment under the control of reaction conditions according to the Sugiyama teaching method of Hachinohe and National College of Technology as illustrated in Production Example 1 of the Example. The product obtained can be used particularly preferably. The amount of carboxyl groups in the regenerated carbon fiber of the present invention usually contains a range of 0.01-0.20 mmol / g. The range that can be preferably used is 0.02-0.15 mmol / g.
The fiber length of the regenerated carbon fiber depends on the size of the CFRP end material of an aircraft or the like and the size of the chips by boring at the time of assembly. In the present invention, the fiber length is referred to as long fiber (100 mm or more), medium fiber (3-100 mm) or powdered fiber (3 mm or less). Either can be preferably used in the present invention.

[Binder for component (C)]
The binder of the component (C) 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. As the skeleton resin, an acrylic resin system or a styrene acrylic resin system is more preferable than a polyolefin system (PP, PS, PE). This is because the solubility parameter of the resin is: raw material PET 10.7, epoxy resin 10.8, polymethyl acrylate 10.2, polyethyl acrylate 9.4, polypropylene (PP) 9.3, polyethyl methacrylate This is because 9.0, POLIS scatter (PS) 8.9, polyethylene (PE) 8.0, and the closer the numerical value, the better the mixing property.
In addition, even if the polyolefin type is mixed at 1-2%, the PET resin film / sheet is clouded, so it is not suitable when the molded product requires transparency. However, since the foam and pipe or the 220 ° C. heat and oil resistant container are white, they can be used for those applications that do not require transparency and for the black molded body of the present invention.

  (C) The compounding quantity of the polyfunctional epoxy compound of a 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 of component (C) and the type and amount of carbon fiber (B). In general, if the amount is less than 0.1 parts by weight, the effect of increasing the molecular weight and melt viscosity is insufficient, so that the moldability is 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 moldability deteriorates, and the resin is yellowed / colored and gel or fish eye (FE) is by-produced.

[(D) Component Binding Reaction Catalyst]
The coupling reaction catalyst as the component (D) 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 polyester (A). 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.

  In the present invention, the binder of component (C) and the coupling reaction catalyst of component (D) are in the form of a masterbatch based on a resin containing at least one of the group consisting of amorphous polyester or polyolefin. Can be used. The actual example was illustrated in Production Example 2 and Production Example 3.

  In the present invention, a spreading agent can be used effectively, but it is particularly effective when the polyester (A) and the carbon fiber (B) are powders. Usually, paraffin oil, liquid paraffin, trimethylsilane or the like can be used. Liquid paraffin is particularly preferred because it is nonpolar, has a high boiling point and is a moderately viscous fluid. The addition amount is 0.01-1 part by weight with respect to the component (A). These spreading agents are necessary for uniformly adhering the (B) component carbon fibers to the (A) polyester pellets or powder, and the carbon fibers / powder soars into the atmosphere. It is an indispensable auxiliary agent necessary to prevent adverse effects on electrical instrumentation equipment.

As the foaming agent of the present invention, a conventional foaming agent can be used. For example, an inert gas such as carbon dioxide and / or nitrogen gas can be used as the volatile foaming agent. These do not cause fires and do not require explosion-proof equipment, so they can be operated in small and medium-sized town factories. Suitable for industrial production of the foam of the present invention having a low expansion ratio.
As the foaming agent of the present invention, a heat decomposable foaming agent can be used. Since the melting point of the polyester resin exceeds 200 ° C., there are few chemical substances that can actually be used. A baking soda-based blowing agent used for low foaming of polypropylene can be used. However, since it is accompanied by the generation of water vapor, short-term equipment maintenance is required for foam molding of polyester resin which is easily hydrolyzed.
Low boiling hydrocarbon compounds such as furopan, butane and hexane can also be used. Suitable for 5 to 20 times higher foaming. However, since the strength of the foam according to the increase in the expansion ratio is drastically reduced, a problem remains. The handling of combustible gas requires explosion-proofing of facilities and buildings, leaving the problem that only large-scale operators can operate.

[Formulation method, reactive extrusion method]
Next, a method for blending the polyester resin of the present invention will be described. As the polyester (A), those having an arbitrary shape such as ordinary virgin pellets, recovered flakes, granules, powders and chips can be used. In general, it is preferable to dry the main component polyester. 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. Suitable when the carbon fiber is in powder form. It is desirable from the viewpoint of the reactive extrusion method that the temperature for melting by heating is 250 degrees or more and 300 degrees or less of the melting point of the polyester. In particular, it is preferably 280 ° C. or lower, particularly preferably 265 ° C. If it exceeds 300 ° C., the surface treatment agent or sizing agent of the carbon fiber may be altered, and the polyester may be discolored or thermally decomposed.
In addition to the simultaneous mixing method described above, as a side feed method, a polyester (A) component, a binder (C) component, and a catalyst (D) component are fed into a twin-screw extruder and subjected to reactive extrusion. The composite material can be produced by injecting the carbon fiber of the component (B) into the outlet portion of the shaft extrusion apparatus to prevent the carbon fiber from being cut. Suitable when the carbon fiber is a short fiber.
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 in powder form. The twin screw extruder is expensive, but is suitable for side-feeding short carbon fibers.

As an application example of the high-strength, lightweight low-foam material of the present invention, for the time being, residential outdoor deck materials and marine 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, the strength of synthetic wood of wood flour / polyethylene (1-3 GPa) and wood flour / polypropylene (about 5 GPa) is too weak compared to the strong strength of natural wood (flexural modulus 6-14 GPa). 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%.
Since the carbon fiber reinforced / modified polyester resin of the present invention has a high strength of a solid molded body (ZOLTEK 30% and a flexural modulus of 22 GPa), development of a low-magnification foam molded body is expected.

Next, the present invention will be described in detail based on examples. The evaluation methods for the polyester and the polyester / carbon fiber composite of the present invention are as follows.
(1) Measuring method of intrinsic viscosity (IV value) of PET, etc. Using a mixed solvent of equal weight of 1,1,2,2-tetrachloroethane and phenol, it was measured at 25 ° C. with a Canon Fuenske viscometer. Or, the manufacturer's catalog value was adopted.
(2) Measurement method of melt flow rate (MFR) According to the condition 20 of JIS K7210, it measured on condition of temperature 280 degreeC or temperature 260 degreeC, and load 2.16kg. However, the resin used was 120 ° C. × 12 hours or 140 ° C. × 4 hours in advance and dried with hot air or vacuum.
(3) Measuring method of specific gravity According to JIS K7112, Method A (submersion method), the resin pellets or small pieces of the molded body were measured with alcohol as a liquid. Or it measured also by the dimension measuring method of JISK7222.
(4) Measuring method of mechanical strength (1) When a small amount of prototype pellets was produced, 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, total 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.).
(5) Measuring method of the amount of acidic functional groups and the amount of carboxyl groups It measured with the Boehm method according to JISK0070. Sodium hydroxide and sodium hydrogen carbonate were individually added to a sample of carbon fiber or polyester, 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. For example, the amount of carboxyl groups is 0.01-0.15 mmol / g on the surface of the carbon material of the battery negative electrode, and 0.04 or less mmol / g for the PET resin.

  The manufacture example about the characteristic raw material concerning this invention is shown. About the carbon fiber of the (B) component which is the main component of this invention, it is preferable to contain an acidic functional group and a carboxyl group for adhesiveness with a polyester resin and bond reactivity with a modifier. New industrial products also contain acidic functional groups and carboxyl groups, though large and small.

Production 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、本発明の焼成後の再生炭素繊維には０．０３−０．０５ｍ ｍｏｌ／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０．１０ｍ ｍｏｌ／ｇ にまで増加していた。尚、ＰＥＴ樹脂では０．０４以下ｍ ｍｏｌ／ｇであるので、本発明の再生炭素繊維のカルボキシル基量は充分である。(B) Manufacture of Regenerated Carbon Fiber Containing Component Acidic Functional Group and Carboxyl Group [Production Examples and Analytical Examples Based on Firing Method of Regenerated Carbon Fiber and Electrolytic Oxidation Method of Alkaline Solution]
According to the patent document (Japanese Patent Laid-Open No. 2013-249386), about 30 kg of CFRP end material generated as a by-product during the assembly of the aircraft is cut to 10 cm square or less, and the thermosetting epoxy resin portion is cut at 400-500 ° C. in an electric furnace. About 15 kg of regenerated carbon fiber (aggregate) was obtained by firing and removal.
5 g of regenerated carbon fiber (aggregate) was placed in a 500 cc beaker and immersed in 200 mL of a 0.1 mol / L sodium hydroxide aqueous solution. Using the regenerated carbon fiber aggregate side as an anode and the cathode side as a titanium electrode, a direct current electrolysis reaction was carried out at 3 V × 0.5 A for 1 hour. The regenerated carbon fiber opened by this electrolytic oxidation treatment was washed with water until neutral, dried and stored. This was repeated three times.
1 g of regenerated carbon fiber was weighed in each 200 cc Erlenmeyer flask and immersed in 50 mL of a 0.1 mol / L sodium hydroxide aqueous solution or sodium hydrogen carbonate aqueous solution. 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 only in a very small amount in new carbon fibers, but 0.03-0.05 mmol / g is also present in the regenerated carbon fiber after firing according to the present invention. Increased 2-3 times to 0.10 mmol / g. In addition, since it is 0.04 or less mmol / g in PET resin, the amount of carboxyl groups of the regenerated carbon fiber of the present invention is sufficient.

  About 1 kg of the regenerated carbon fiber aggregate obtained above was placed in a 10 L electrolytic cell, and a potassium hydroxide aqueous solution was filled. The regenerated carbon fiber aggregate was used as a copper anode side, and the cathode side was used as a titanium electrode, and a low current / low voltage DC electrolytic reaction was carried out for 4 hours. Although most of the regenerated carbon fiber aggregates were opened, they were further mechanically opened to obtain a black glossy regenerated carbon fiber. The fiber length was 5-10 cm. Regenerated carbon fiber containing about 50% alkaline water was neutralized with an acidic solution, washed with water, dried at 180 ° C. overnight and stored. The same operation was repeated several times to produce 5 kg of regenerated carbon fiber.

Production Example 2

(C) Component and (D) component modifier master batch (MB-G)
[Manufacturing example of modifier masterbatch (MB-G) using PETG as a substrate for component (C) and component (D)]
The modifier master batch (MB-G) is usually composed of a one-to-one blend of the pellets for the binder master batch of component (C) and the catalyst master batch of component (D).
[1] Example of production of binder masterbatch of component (C) As a binder of component (C), as a representative example of a polyfunctional epoxy compound containing two or more epoxy groups in the molecule, NOF Corporation's Employing “Marproof G-0130SP” (epoxy number 10 / number average molecular weight, number average molecular weight 5,500, epoxy equivalent 530 g / eq .: abbreviation “EP-A”) A non-crystalline copolyester “Eastar PETG 6763” was used.
First, 15 parts by weight (15 Kg, white powder) of this EP-A, 50 parts by weight (50 Kg) of pulverized white powder of PETG 6763 as a base resin, 50 parts by weight (50 Kg) of transparent pellets of PETG 6763, and a spreading agent 115.1 kg of the liquid paraffin 0.1 wt. (0.10 kg) was mixed with a Henschel mixer.
Using the same direction twin screw extruder (screw diameter 70 mm, L / D = 32, 2 vent type) manufactured by Toshiba Machine Co., Ltd., the set temperature of the cylinder and the die is 100-220 ° C. and the screw rotation speed is 160 rpm, 115 kg of the blend was top fed from the hopper via a volume feeder. The resin pressure of the strand mold was 4.9 to 5.0 MPa, the strand from the mold outlet to the water basin was linear and stable, and the discharge speed was 117 kg / h.
This warm white pellet A agent (the binder masterbatch of component (C)) was immediately transferred to a hopper at 70 ° C., fluidized and dried overnight, and then stored in a three-layer moisture-proof bag of paper, aluminum, and polyethylene. Yield was 107 kg.

[2] Example of production of catalyst masterbatch of component (D) White powdery composite catalyst (abbreviation: "" comprising 50% calcium stearate, 25% lithium stearate and 25% sodium stearate as a representative example of the catalyst for the binding reaction. C10 ") 10 parts by weight (10 Kg), 50 parts by weight (50 Kg) of pulverized white powder of PETG 6763 as a base resin, 50 parts by weight (50 Kg) of transparent pellets of PETG 6863, and liquid paraffin 0.2 as a spreading agent Part by weight (0.20 Kg) of the formulation, 110.2 Kg, was mixed with a Henschel mixer. This was transferred to a hopper on the extruder. Extrusion was carried out in substantially the same manner as described above. The resin pressure of the strand mold was 7.1 to 9.6 MPa, the white strand from the mold outlet to the water basin was linear and stable, and the discharge speed was 200 kg / h. This warm white pellet B agent (catalyst masterbatch of component (D)) was immediately transferred to a hopper at 70 ° C., fluidized and dried overnight, and then stored in a three-layer moisture-proof bag of paper, aluminum and polyethylene. Yield was 102 kg.
100 kg of binder master batch A agent of component (C) and 100 kg of catalyst master batch B agent of component (D) were blended one-on-one to produce 200 kg of modifier master batch (MB-G). .

Production Example 3

(C) Component and (D) component modifier masterbatch (MB-E)
[Production Example of Modifier Master Batch (MB-E) Using Polyethylene as Base for Component (C) and Component (D)]
The modifier masterbatch (MB-E) is usually composed of a 2 to 1 blend of the pellets for the binder masterbatch of component (C) and the catalyst masterbatch of component (D).
[1] Example of production of binder masterbatch of component (C) A pulverized product of low density polyethylene (MI 2) was used instead of PETG as a base resin, and a binder of component (C): abbreviation EP-A The same procedure as in Production Example 2 was carried out with a concentration of 15 parts by weight and 1 part by weight of talc as a crystal nucleating agent. This warm white pellet AE agent (the binder masterbatch of component (C)) was immediately transferred to a hopper at 70 ° C., fluidized and dried overnight, and then stored in a three-layer moisture-proof bag of paper, aluminum, and polyethylene. The yield was about 100 kg.
[2] Production example of catalyst master batch of component (D) Low-density polyethylene pulverized product (MI 2) was used as the base resin instead of PETG, and composite catalyst of component (D): 10 parts by weight of abbreviation C10 This was carried out in the same manner as in Production Example 2. This warm white pellet BE agent (catalyst masterbatch of component (D)) was immediately transferred to a hopper at 70 ° C., fluidized and dried overnight, and stored in a three-layer moisture-proof bag of paper, aluminum, and polyethylene. The yield was about 100 kg.
The binder master batch AE agent of component (C) and the white pellets of catalyst master batch BE agent of component (D) were blended 2 to 1 to produce 150 kg of modifier master batch (MB-E).

Production Example 4

[Production of ZOLTEK Carbon Fiber Reinforced / Modified Pet Resin Pellets R1 Consisting of 15% Pet Resin, Carbon Fiber Chop, and Modifier]
General-purpose pet resin pellets (bottle grade: Taiwan / South Asia 3802T, IV value 0.80) as polyester for component A, polyfunctional epoxy resin as binder for component C and 100 parts by weight (moisture content after drying of about 100 ppm or less) 0.60 part by weight, 0.16 part by weight of the mixed catalyst for the D component binding reaction and 0.06 part by weight of liquid paraffin as a spreading agent for the E component were uniformly mixed by a super mixer. These were delivered to the first hopper for main resin extrusion. On the other hand, as the carbon fiber of component B, Toshiba carbon fiber chops (PAN-based carbon fiber “Panex35” 6 mm long from Taito (LT) rayon from ZOLTEK, USA) were delivered to the second hopper for the side feeder. The same direction twin screw extruder (caliber: 60 mm, 1 vent type) manufactured by Co., Ltd. was used, and the set temperature of the cylinder and the die consisting of 10 blocks of this extruder was 150 to 270 ° C. and the screw rotation speed was 150 rpm. Using a gravimetric weighing feeder, a mixed resin such as A component, C component, and D component is reactively extruded from the first hopper at a rate of 100 kg / h, and a carbon fiber chop is fed from the second hopper to 17.6 kg / h. Side feed was continuously performed at a rate of (carbon fiber content: 15%).
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 180 kg of black resin pellet R1. The strand from the mold outlet to the basin was 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 (260 degreeC, load 2.16Kg) was 6.2g / 10min.
This carbon fiber reinforced / modified pet resin black pellet R1 is dried with hot air overnight at 120 ° C., and a hybrid injection molding machine FNZ60 manufactured by Nissei Plastic Industry Co., Ltd. (clamping pressure 140 tons, screw diameter 60 mm) is used. The following injection molded article was molded under the conditions of a molding temperature of 280 ° C., a mold temperature of 130 to 145 ° C., an injection pressure of 53 MPa, an injection speed of 12 mm / s, a screw rotation speed of 80 rpm, and a cooling time of 20 seconds.
Shape of multi-purpose test piece: ISO 20553, 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)
This ZOITEK carbon fiber (CF15%) reinforced / modified pet resin pellet R1 showed no injection by-product and showed good injection moldability. The surface of the test piece was smooth and glossy. The test was performed at a tensile speed of 2 mm / min and a bending speed of 5 mm / min. The physical property values of the pellets are shown in Table 1.
Compared to the sticky resin-only transparent pellet P1 of Production Example 8, the mixing effect of ZOLTEK carbon fiber of about 15% in this Example R1 is 2.9 times the tensile strength, 4.1 times the Young's modulus, and the bending strength. It is 3.5 times and the flexural modulus is 5.7 times.

Production Example 5

[Production of ZOLTEK Carbon Fiber Reinforced / Modified Pet Resin Pellets R2 Composed of PET Resin, Carbon Fiber Chop 30%, and Modifier] ZOL 30%
Pellets R2 were produced under substantially the same conditions as in Production Example 4 above. However, the side feed speed was doubled to reduce the carbon fiber chop content to about 30%. General-purpose pet resin pellets (bottle grade: Taiwan / South Asia 3802T, IV value 0.80) as polyester for component A, polyfunctional epoxy resin as binder for component C and 100 parts by weight (moisture content after drying of about 100 ppm or less) 0.56 parts by weight, 0.16 parts by weight of the mixed catalyst for the D component binding reaction and 0.06 parts by weight of liquid paraffin as the E component spreading agent were uniformly mixed by a super mixer. These were delivered to the first hopper for main resin extrusion. Meanwhile, an LT carbon fiber chop (a rattan PAN-based carbon fiber “Panex 35”, 6 mm long from ZOLTEK, USA) as a B-component carbon fiber was delivered to a second hopper for a side feeder.
A twin-screw extruder in the same direction (caliber 60 mm, 1 vent type) was used, and the set temperature of the cylinder and die comprising 10 blocks of this extruder was 150 to 270 ° C. and the screw rotation speed was 150 rpm. Using a gravimetric weighing feeder, a mixed resin such as A component, C component, and D component is reactively extruded from the first hopper at a rate of 100 Kg / h, and a carbon fiber chop from the second hopper is 42 Kg / h (carbon Side feed was continuously performed at a rate of 30% fiber content).
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 250 kg of black resin pellet R2. The strand from the mold outlet to the water basin was linear and the melt tension was increased. The shape of the strand was cylindrical and the diameter was about 3.4 mm × length was about 6 mm. Moreover, MFR (260 degreeC, load 2.16Kg) was 6.7 g / 10min. This carbon fiber (CF 15%) reinforced / modified pet resin pellet R2 showed no injection by-product and showed good injection moldability, and the surface of the test piece was almost smooth and glossy. The physical property values of the pellets are shown in Table 1. Compared with the transparent pellet P1 made only of the PET resin of Production Example 8, the mixing effect of ZOLTEK carbon fiber of about 30% of this Example R2 is 3.5 times the tensile strength, 6.1 times the Young's modulus, and 3 times the bending strength. It was 9 times and the flexural modulus was 10.3 times. Carbon fiber reinforced / modified PET resin pellets with good injection moldability and greatly improved mechanical strength were obtained.

Production Example 6

[Manufacture of recovered carbon fiber reinforced / modified pet resin pellets R3 consisting of approximately 15% PET resin and recovered carbon fiber chop and a master batch of modifier]
Commercially available PET (PET) resin pellets (polyester bottle grade: IV value 0.80, MFR 35 g / 10 min, 280 ° C., 2.16 Kg) as component A polyester 100 parts by weight (120 Kg; hot air at 120 ° C. for 12 hours Moisture content after drying of about 100 ppm) and modifier masterbatch (MB-G: PETG substrate, Production Example 2) 6 parts by weight (7.2 Kg; polyfunctional epoxy resin as conjugate of component C: EP-A And 0.45 parts by weight of D component coupling reaction catalyst: 0.30 parts by weight of C10) were mixed using a tumbler at 30 rpm × 10 minutes. These were delivered to the first hopper.
A recovered carbon fiber chop (collected bobbin-wound PAN-based carbon fiber and cut into 6 mm length, 40 kg) was delivered to the second hopper as the B component carbon fiber.
The same direction twin screw extruder (ZE40E: screw diameter 42 mm, L / D = 38) manufactured by Berstolf, Germany, was used, and the set temperature of the cylinder and the die consisting of 10 blocks of this extruder was 150-270 ° C. and The screw rotation speed was 100 rpm, and the recovered carbon fiber chop was continuously injected into the fifth block.
Using a gravimetric weighing single screw feeder, mixed resin pellets of A component, C component and D component from the first hopper at a speed of 18.02 kg / h, and recovered carbon fiber chop from the second hopper at 3.0 kg / h It was charged into the extruder at a rate of h (carbon fiber content 14.3%).
Three strands were continuously extruded into water from a diagonally downward nozzle having a diameter of 3 mm, and cut with a rotary cutter at a take-up speed of 20 m / min to produce a black resin pellet R1. The resin pressure of the strand mold was 0.90 to 1.2 MPa, and the strand from the mold outlet to the basin was linear and the melt tension increased.
The yield of this warm black resin pellet was (20.6 kg) R3 was immediately dried in hot air at 120 ° C. overnight and stored in a three-layer moisture-proof bag of paper, aluminum and polyethylene. The shape was cylindrical and had a diameter of about 2.5 mm and a length of about 4.5 mm. Moreover, MFR (280 degreeC, load 2.16Kg) was 35 g / 10min.

This recovered carbon fiber (15%) reinforced / modified pet resin black pellet R3 was re-dried under vacuum, and an injection molding machine SE18DUZ manufactured by Sumitomo Heavy Industries, Ltd. (clamping pressure 18 tons, screw diameter 16 mm / SL screw), molding temperature 270-280 ° C., mold temperature 37-38 ° C., injection pressure 64-70 MPa, injection speed 20 mm / s, screw rotation speed 100 rpm, and cooling time 15 seconds. An injection molded body was molded.
Shape of injection-molded body: small piece for tensile test JIS K7162 5A type (thickness 2 mm)
In addition, the same molding apparatus was used and the following injection molded body was molded under the conditions of almost the same conditions but with an injection pressure of 115 to 123 MPa and a cooling time of 20 seconds. Shape of injection molded body: small piece for bending test The strip type was 80 mm long × 10 mm wide (thickness 4 mm). Both showed no injection of burrs and showed good injection moldability. The physical properties of the pellet R3 are shown in Table 2. Compared to the transparent pellet P1 made only of Pette resin in Production Example 8, the tensile strength was 2.0 times, Young's modulus was 2.1 times, flexural strength was 2.3 times, and flexural modulus was 3.9 times. .

Production Example 7

[Manufacture of recovered carbon fiber reinforced PET resin pellet R4 consisting of approximately 30% PET resin and recovered carbon fiber chop and a master batch of modifier]
Pellets R4 were produced under substantially the same conditions as in Production Example 6 above. However, in order to reduce the content of the recovered carbon fiber chop to about 30%, the supply rate was doubled to reduce the supply rate of the pet resin.
That is, as a polyester of component A, commercially available PET (PET) resin pellets (general-purpose bottle grade: IV value 0.80, MFR 25 g / 10 minutes, 280 ° C., 2.16 Kg) 100 parts by weight (120 Kg; 120 ° C., 12 hours) Water content after hot air drying of about 100 ppm) and modifier masterbatch (MB-G: PETG substrate, Production Example 2) 6 parts by weight (7.2 Kg; polyfunctional epoxy resin 0.45 as a C component conjugate) Parts by weight and 0.30 parts by weight of the D component coupling reaction catalyst) were mixed using a tumbler at 30 rpm × 10 minutes. These were delivered to the first hopper. A recovered carbon fiber chop (collected bobbin-wound PAN-based carbon fiber and cut into 6 mm length, 40 kg) was delivered to the second hopper as the B component carbon fiber.
The same direction twin screw extruder (ZE40E: screw diameter 42 mm, L / D = 38) manufactured by Berstolf, Germany, was used, and the set temperature of the cylinder and the die consisting of 10 blocks of this extruder was 150-270 ° C. and The screw rotation speed was 150 rpm, and the recovered carbon fiber chop was continuously injected into the fifth block.
Using a gravimetric weighing single screw feeder, mixed resin pellets of A component, C component and D component from the first hopper at a speed of 14.84 kg / h, and recovered carbon fiber chop from the second hopper to 6.0 kg / The extruder was charged at a rate of h (carbon fiber content: 28.8%).
Three strands were continuously extruded into water from an obliquely downward nozzle having a diameter of 3 mm, and cut with a rotary cutter at a take-up speed of 20 m / min to produce black resin pellets R2. The resin pressure of the strand mold was 1.1 to 1.2 MPa, and the strand from the mold outlet to the water basin was linear and the melt tension increased.
This warm black resin pellet R465 Kg was immediately dried with hot air overnight at 120 ° C. and then stored in a three-layer moisture-proof bag of paper, aluminum, and polyethylene. The shape was cylindrical and had a diameter of about 3 mm and a length of about 5 mm. Moreover, MFR (280 degreeC, load 2.16Kg) was 25 g / 10min.
This black pellet R4 was re-dried under vacuum, using an injection molding machine SE18DUZ manufactured by Sumitomo Heavy Industries, Ltd. (clamping pressure: 18 tons, screw diameter: 16 mm / SL screw), under substantially the same conditions as in Production Example 6. However, the following injection-molded article was molded under the condition of an injection pressure of 116 to 121 MPa. Shape of injection-molded body: JIS K7162 5A type (thickness 2 mm) for tensile test pieces. Further, the same molding apparatus was used, and the following injection molded body was molded under the conditions of injection pressure 120 to 124 MPa under substantially the same conditions as in Production Example 6: Shape of injection molded body: for bending test piece Strip type Length 80 mm x width 10 mm (thickness 4 mm).
This carbon fiber reinforced pet resin pellet R6 has a mixed strength of about 30% recovered carbon fiber (6 mm long chop) compared to the transparent pellet P1 made only of PET resin in Production Example 8, and has a tensile strength of 2.4. The Young's modulus was 5.0 times, the flexural strength was 2.8 times, and the flexural modulus was 6.8 times.

Production Example 6

[Manufacture of pellets P1 using only pet resin]
Production Examples 4 and 5 using only 100 parts by weight (3 Kg) of component A PET resin (Pellets of commercially available general-purpose products for PET bottles: IV value 0.80, MFR 35 g / 10 min, 280 ° C., 2.16 Kg) Repellet P1 was produced under substantially the same extrusion conditions as in Example 1, and 2.9 kg of transparent pellets were obtained. The strand drooped in an arc from the mold outlet to the water surface, meandering in the basin, indicating a low melt tension. The transparent pellet P1 was cylindrical and had a diameter of about 3 mm and a length of about 5 mm. Moreover, MFR (280 degreeC, load 2.16Kg) was 57 g / 10min, and was comparatively low melt viscosity.
This PET resin-only pellet P1 was injection-molded to form tensile test pieces and bending test pieces in the same manner as in Production Examples 6 and 7. The tensile strength was 59 MPa, the Young's modulus was 1.9 GPa, the bending strength was 84 MPa, and the flexural modulus was 2.1 GPa.

Production Example 9

[Production of recovered carbon fiber reinforced / modified PET bottle flake pellets R5 (99% recycled) consisting of 15% PET bottle flakes and recovered carbon fiber chop and a modifier]
Commercially available PET bottle flakes as a polyester of A component (general-purpose product of Nishitokyo Tsusho Co., Ltd .: IV value 0.73, MFR 57 g / 10 min, 280 ° C., 2.16 Kg) 100 parts by weight (at 120 ° C. for 2 hours) Water content after vacuum drying of about 100 ppm or less), 0.70 part by weight of a polyfunctional epoxy resin (EP-A) as a binder for component C, 0.15 part by weight of a mixed catalyst for the binding reaction of component D and component E 0.05 parts by weight of liquid paraffin as a spreading agent was uniformly mixed with a tumbler. These were delivered to the first hopper for main resin extrusion. On the other hand, the recovered carbon fiber chop (collected bobbin-rolled PAN-based carbon fiber and cut into 6 mm length) was delivered to the second hopper for the side feeder.
Using a twin-screw extruder in the same direction (caliber 35 mm, L / D 35) manufactured by Hitachi Zosen Co., Ltd., the set temperature of the cylinder and strand mold of this extruder is 150-270 ° C. and the screw rotation speed is 150 rpm. did. Using a capacity-type weighing feeder, reactive extrusion of the composition of component A, component C and component D from the first hopper at a rate of 17 kg / h, and carbon fiber chop using the meter from the second hopper Was continuously side-fed at a rate of 3 kg / h (carbon fiber content: 15%).
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 200 kg of black resin pellet R5. The strand from the mold outlet to the basin was linear and the melt tension increased. The shape was cylindrical and the diameter was about 3.4 mm × length was about 6 mm. Further, MFR (260 ° C., load 2.16 Kg) was 4.2 g / 10 minutes, and the melt viscosity was sufficiently increased.

[Manufacture of thin flat plate and foamed plate by horizontal extrusion method from ZOLTEK carbon fiber reinforced / modified pet resin pellet R1 composition consisting of 15% pet resin, new carbon fiber chop and modifier]
ZOLTEK carbon fiber (15%) reinforced PET resin dried black pellets R1 (MFR 6.2 g / 10 min: 260 ° C., load 2.16 Kg) 100 parts by weight, binder (EP-A) zero or 0.4 weight Part, catalyst (C10) zero or 0.2 parts by weight and chemical blowing agent pellet EE405F (manufactured by Eiwa Kasei Kogyo Co., Ltd., baking soda-based polyethylene substrate, gas generation amount 66 ml / g, mainly carbon dioxide) zero or 2.5 Part by weight and 0.1 part by weight of liquid paraffin as a spreading agent were mixed in advance and put into a hopper.
A raw material feeder, a deformed mold, a resin pressure measuring sensor, an air cooler, a stainless steel sliding plate, a water pan, and a take-up machine were installed in a twin-screw extruder (caliber 15 mm, L / D30) manufactured by Technobel. At the screw temperature of 245 to 280 ° C., the rotational speed of 1150 rpm, the mold temperature of 250 to 260 ° C., the feed rate of the blend such as pellets is 1-2 kg / h, and the take-up speed is 1-2 m / min. Extruded horizontally. Taking into account the resin's melt viscosity, fluidity, shrinkage, etc., the deformed mold has a drum shape (width 25 mm: center gap 2.5 mm, gap at both ends 1.5 mm), and foam plate for thin flat plates For this purpose, a drum shape (width 25 mm: center gap 2.5 mm, both end gap 4.5 mm) was used. The test results are summarized in Table 3.
In the deformed shape by the horizontal extrusion method, as the resin pressure increases, the production of the molded body becomes more stable, and as the molded body approaches the width (25 mm) and the gap (25 mm) of the deformed mold, the molding process is successful. Get closer to. In the present invention, the expansion ratio is preferably 1.5-3 times. It is aimed at huge uses of natural and synthetic wood.
In the production of the thin flat plate of Example 1-S1, the resin pressure was 0.1 MPa, the melt tension of the resin was low, neck-in occurred on the left and right and top and bottom of the thin flat plate, and the molded body became thin and thin. In the production of the foam board of Example 1-F1, the width and thickness were increased when 2.5 parts of the foaming agent was added, but this was insufficient. Furthermore, in the production of the foam plate of Example 1-F2, when 2.5 parts by weight of the binder (EP-A) and 0.2 parts by weight of the catalyst (C10) were added as modifiers in addition to 2.5 parts of the foaming agent, As the resin pressure doubled, the width (19 mm) and thickness (2.3 mm) of the foam plate increased, and the foaming ratio reached 1.5 times. These can be further improved and controlled by increasing the amount of foaming agent added from 2.5 parts to 3-4 parts. In particular, the foamed plate of Example 1-F2 had good surface smoothness, a stable molding state, and a remarkable effect of adding a modifier regardless of the use of a dimension adjusting mold.

[Manufacture of thin flat plates and foamed plates by horizontal extrusion from a composition such as ZOLTEK carbon fiber reinforced / modified pet resin pellets R2 comprising 30% pet resin, 30% carbon fiber chop and a modifier]
Production of thin flat plates and foamed plates was carried out under the same extrusion conditions and operations as in Example 1. The test results are summarized in Table 3. ZOLTEK carbon fiber (30%) reinforced PET resin dried black pellet R2 (MFR 6.7 g / 10 min: 260 ° C., load 2.16 Kg) 100 parts by weight, binder (EP-A) zero or 0.4 weight Parts, catalyst (C10) zero or 0.2 parts by weight and chemical blowing agent pellet EE405F (manufactured by Eiwa Chemical Industry Co., Ltd., gas generation amount 66 ml / g) zero or 2.5 parts by weight, and liquid paraffin as a spreading agent Zero or 0.1 parts by weight were premixed and charged into the hopper.
In the production of the thin flat plate of Example 2-S2, the resin pressure was 0.2 MPa and the melt tension of the resin was slightly low, so that neck-in occurred on the thin flat plate from left to right and up and down, and the compact was thin and thin. Next, in the production of the foam board of Example 2-F3, when 2.5 parts of the foaming agent was added, the width (18 mm) and thickness (2.1 mm) were increased, and the foaming ratio reached 1.5 times. . In addition, in the production of the foam plate of Example 2-F4, when 2.5 parts by weight of a binder was added as a modifier in addition to 2.5 parts by weight of the foaming agent, the resin pressure was increased 10 times. While increasing to 2.3 MPa, the width (18 mm) and thickness (2.1 mm) of the foam plate increased, and the expansion ratio reached 2.0 times the target for the time being. As can be seen from the examples, the addition of a modifier is necessary and indispensable in the production of foamed plates.

[Manufacture of thin flat plate and wide foamed plate by extrusion method from recovered carbon fiber reinforced / modified PET resin pellet R3 consisting of 15% PET resin, recovered carbon fiber chop and modifier masterbatch]
Recovered carbon fiber (15%) reinforced / modified PET resin dried black pellets R3 (MFR 35 g / 10 min: 280 ° C., load 2.16 Kg) has a relatively high melt viscosity due to its high MFR. Therefore, in the same manner as in Example 1, a thin flat plate was horizontally extruded to test and determine in advance the amount of modifier masterbatch necessary for foaming. Using the test equipment of Example 1, a thin flat plate was horizontally extruded with 100 parts by weight of black pellets R3, zero modifier masterbatch (MB-E), and 2, 4 parts by weight. However, taking into account the melt viscosity, fluidity, and shrinkage of the resin, the deformed mold was a rectangular shape (width 25 mm: center gap 1.5 mm). The test results are summarized in Table 4. As the addition amount of the modifier (MB-G) was increased, the resin pressure increased and the width and thickness of the thin flat plate increased remarkably, so the optimum addition amount was 6 parts by weight.
A wide foamed plate was produced using a T-die type film / sheet extrusion production apparatus manufactured by Soken Co., Ltd. (Example 3-F5). The main extruder is a single screw, 30 mm diameter, L / D 38, and the sub-extruder is a single screw, 25 mm diameter, L / D 25. The T-die has a width of 250 mm, a lip gap of 1.5 mm, a vertical type, and a feed block type. The polishing roll is made of stainless steel with a mirror finish and oil temperature control. The guide roll is hot water controlled. The take-up machine is a pneumatically controlled rubber roll.
Dry recovered carbon fiber (15%) reinforced / modified PET resin black pellet R3 (MFR 35 g / 10 min: 280 ° C., load 2.16 Kg) 100 parts by weight, modifier masterbatch (MB-E) 6 parts by weight Parts, chemical foaming agent pellets EE405F (manufactured by Eiwa Chemical Industry Co., Ltd., gas generation amount 66 ml / g) 2.5 parts by weight, calcium stearate 0.1 parts by weight as a lubricant and liquid paraffin 0.05 parts by weight The parts were mixed in advance and charged into the hopper of the main extruder. The sub-extruder was stopped from heating. A wide foam plate was produced at a cylinder temperature of 255-265 ° C., a T-die temperature of 245-260 ° C., a screw rotation of 70 rpm, and a roll temperature of 40-70 ° C., and a take-up speed of 0.4 m / min. The resin pressure was 5.5 MPa. The wide foam plate had a width of 25 cm, no neck-in, a thickness of 2.8 mm, twice the lip gap, and a foaming ratio of 2.1 times. According to the present invention, a substantially targeted foam could be produced (Example 3-F5).

[Manufacture of thin flat plate and 2 types, 3 layers wide foamed plate by extrusion method from recovered carbon fiber reinforced / modified PET resin pellet R4 consisting of PET resin, recovered carbon fiber chop 30% and modifier masterbatch]
Recovered carbon fiber (30%) reinforced / modified PET resin dried black pellet R4 (MFR 25 g / 10 min: 280 ° C., load 2.16 Kg) has a relatively low melt viscosity. The amount of modifier masterbatch, which is indispensable for foaming, was tested and determined in advance by horizontally extruding a flat plate. Using the test facility of practical example 1, 100 parts by weight of black pellet R4, 4 parts by weight of modifier masterbatch (MB-E), 0.1 parts by weight of calcium stearate as a lubricant and fluid as a spreading agent A composition of 0.05 part by weight of paraffin was premixed and a thin flat plate was produced by a horizontal extrusion method. The test results are summarized in Table 5. In the thin flat plate, as the amount of the modifier (MB-G) added was increased, the resin pressure increased and the thickness of the thin flat plate increased slightly, so the optimum addition amount was 6 parts by weight.
The production of the two-type, three-layer wide foam plate was carried out using a T-die type film / sheet extrusion production apparatus manufactured by Soken Co., Ltd. in Example 3 (Example 4-F6). In the main extruder, a composition of 0.1 part by weight of calcium stearate as a modifier, a foaming agent, a lubricant and 0.05 part by weight of liquid paraffin as a spreading agent was extruded onto a single-layer foamed plate. On the other hand, the same resin R4, 0.1 parts by weight of calcium stearate as a lubricant and 0.05 parts by weight of liquid paraffin as a spreading agent were extruded from the sub-extruder, and covered with a feed block T-die as a skin layer from the outside. Thus, a wide foam plate of 2 types and 3 layers was obtained. Dry recovered carbon fiber (30%) reinforced / modified PET resin black pellets R4 (MFR 25 g / 10 min: 280 ° C., load 2.16 Kg) 100 parts by weight, modifier masterbatch (MB-E) 6 parts by weight And 2.5 parts by weight of chemical foaming agent pellets EE405F (manufactured by Eiwa Kasei Kogyo Co., Ltd., gas generation amount 66 ml / g) were mixed in advance and charged into the hopper of the main extruder. The cylinder temperature of the main extruder was 255-265 ° C., the temperature of the T die was 245-260 ° C., the screw rotation was 70 rpm, the resin pressure was 5 MPa, and the roll temperature was 40-70 ° C. On the other hand, the pellet R4 was put into the hopper of the sub-extruder, the cylinder temperature was set to 260-270 ° C., the screw rotation was 15 rpm, and the resin pressure was 3 MPa. As a result, a two-type, three-layer wide foam plate could be produced at a take-up speed of 0.4 m / min. This wide foam plate had a width of 24 cm, had a slight neck-in, a thickness of 3.0 mm, twice the lip gap, and an expansion ratio of 1.9 times as an average of the three-layered body. According to the present invention, almost the target two-kind three-layer foam could be produced (Example 4-F6).

[Manufacturing of foamed board by carbon dioxide gas method of recovered carbon fiber reinforced / modified PET bottle flake pellets R5 (99% recycled) consisting of 15% PET bottle flakes and recovered carbon fiber chop and a modifier]
Hitachi Zosen's twin screw extruder (caliber 60 mm, L / D 40), first hopper and weight-type weighing machine, second hopper and capacity-type weighing machine, vent type vacuum line, temperature control device, carbonic acid A gas injection device, an injection line, a gear pump, a T die (width 1,200 mm, for horizontal extrusion), a cooling device, a take-up device, an automatic cutter, and the like were installed.
The first hopper is loaded with undried recovered carbon fiber reinforced / modified PET bottles / flakes pellets R5 (MFR 4.2 g / 10 min: 260 ° C., load 2.16 Kg), and the second hopper is modified. Agent pellets (MB-E) were charged. In the extruder, the temperature of the cylinder, gear pump and T die was set to 240 to 280 ° C., the extrusion rate of the resin composition was 75 kg / h, and the carbon dioxide injection rate was 2.5 to 5 g / min under high vacuum. . The addition amount of modifier pellets (MB-E) in the second hopper was controlled to control the screw tip pressure to 6-7 MPa. In this way, a foam board having a width of 120 cm, an average thickness of 2.2 to 2.4 mm, and a foaming ratio of 2 to 4 times was produced.

According to the present invention, in the production of carbon fiber reinforced / modified polyester resin, by using a modifier (a binder and a catalyst) in combination, and by increasing its melt viscosity, it has been difficult to perform conventional extrusion molding. In addition, it has become possible to produce a molded product of the horizontal extrusion method very stably. In addition, this new material has been able to dramatically increase the mechanical strength by strengthening the carbon fiber, and has been able to reduce the weight by foaming. Various physical properties such as corrosion resistance, heat resistance, heat transfer conductivity, oil resistance, and weather resistance can also be improved. Also, recovered carbon fiber, recycled carbon fiber from carbon fiber reinforced epoxy resin composite, and inexpensive new carbon fiber strength can be used.
The present invention is intended for civil engineering and building materials for the time being. In the near future, we will target applications for further weight and energy savings by improving the strength of interior materials and components in advanced industries such as the railway vehicle, automobile industry, Shinkansen vehicle industry, linear motor car and aerospace industry. To do. 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 (7)

Polyfunctional epoxy compound containing 100 parts by weight of (A) component polyester, 5 to 150 parts by weight of (B) component carbon fiber, and two or more epoxy groups in the molecule as binder for (C) component. A composition composed of 1 to 2 parts by weight and 0.01 to 1 part by weight of the (D) component binding reaction catalyst is heated at a temperature equal to or higher than the melting point of the polyester to reinforce and modify carbon fiber with high melt viscosity A method for producing a foamed article of carbon fiber reinforced / modified polyester resin, wherein a foaming agent is added to foam after forming a polyester resin. 2. The carbon fiber according to claim 1, wherein the polyester as component (A) contains at least one of polyethylene terephthalate, polybutylene terephthalate, polycarbonate, or a recycled product of the recovered molded product thereof A method for producing a foamed molded article of a reinforced / modified polyester resin. The carbon fiber of the component (B) contains at least one of the group consisting of recovered carbon fiber short fiber or powdered fiber, regenerated carbon fiber short fiber or powdered fiber, The manufacturing method of the foaming molding of the carbon fiber reinforced and modified polyester resin of Claim 1. (B) Carbon fiber short fiber or powder fiber of industrial product, carbon fiber short fiber or powder fiber of industrial product that has been subjected to electrochemical oxidation treatment, or chemical oxidation-treated industry The method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, comprising at least one of short fibers or powder fibers of carbon fibers of the product. The method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a volatile foaming agent and is an inert gas such as carbon dioxide gas or nitrogen gas. The method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a heat decomposable foaming agent. The method for producing a foamed article of carbon fiber reinforced / modified polyester resin according to claim 1, wherein the foaming agent is a hydrocarbon compound having a low boiling point.