JP2004331741A - Composite resin material and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite material the mechanical properties of which can be improved even when an additive is added in a small amount. <P>SOLUTION: The composite resin material is characterized in that by crystallizing a crystalline resin material by mixing with vapor-phase-grown carbon fibers being a laminate of carbon network layers in the form of a bottomless cup, the resin material around the carbon fibers are crystallized, and an internal network structure is formed from the carbon fibers and the crystallized resin material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００３２】
実施例２
あらかじめ９０℃の真空オーブン中で８時間乾燥させ、水分を除去した粉状ポリプロピレン（ＰＰ）とジーエスアイクレオス社製カルベールＬｏｎｇＣＮＴ（底のないカップ状をなす炭素網層が多数積層した炭素繊維。直径８０〜１５０μｍ、アスペクト比が約２００に調整したもの）を、ＰＰに対して炭素繊維が０．３ｗｔ％となるように計りとった。これに溶媒としてヘキサンを加え、固形分が１０ｗｔ％になるように溶液を調整し、この溶液をガラスシャーレにキャスティングし、室温で乾燥させた。次ぎに、試料の熱履歴を取り、溶媒を完全に除去し、かつ一体化するために、混合材料を約１９０℃の温度で溶融し、次いで、融点温度よりも低い約１４０℃の温度で約１０分間保持し、結晶化を促進した。また得られた樹脂材料をホットプレスにより任意の形状に成形して複合樹脂材を得た。
実施例１と同様に、炭素繊維を０．３ｗｔ％配合したものは、炭素繊維を配合しないものに比して結晶化時間を約半分に短縮できた。またＰＰの結晶単位格子はａ、ｂ、ｃ軸共に約０．５％減少した。さらに弾性率も約２００％向上した。
また、前記図１１、図１２の、複合樹脂材をキシレンで約１０秒間エッチング処理したサンプルの表面の電子顕微鏡写真から明らかなように、炭素繊維および炭素繊維の周囲に結晶化した樹脂により網目構造が形成されていることがわかる。
【００３３】
【発明の効果】
以上のように本発明によれば、気相成長法による炭素繊維を配合して結晶化処理を行うことで、炭素繊維の周囲に結晶性樹脂材料を効率よく短時間で結晶させることができ、高速成形性が得られると同時に、炭素繊維、および炭素繊維の周囲に形成された結晶化した樹脂により網目構造が形成され、機械的強度に優れるとともに、導電性、熱伝導特性も向上する複合樹脂材を提供できる。
【図面の簡単な説明】
【図１】気相成長法によって製造したヘリンボン構造の炭素繊維の透過型電子顕微鏡写真の複写図である。
【図２】図１の拡大図である。
【図３】図２の模式図である。
【図４】約５３０℃の温度で、大気中１時間熱処理したヘリンボン構造の炭素繊維の透過型電子顕微鏡写真の複写図である。
【図５】図４の拡大図である。
【図６】図５のさらに拡大図である。
【図７】図６の模式図である。
【図８】ヘリンボン構造の炭素繊維（サンプルＮＯ．２４ＰＳ）を、大気中で、１時間、それぞれ５００℃、５２０℃、５３０℃、５４０℃で熱処理した後の、炭素繊維のラマンスペクトルを示す。
【図９】上記熱処理を行って炭素網層の端面を露出させた、サンプルＮＯ．１９ＰＳと、サンプルＮＯ．２４ＰＳの炭素繊維のラマンスペクトルを示す。
【図１０】上記炭素網層の端面を露出させた、サンプルＮＯ．１９ＰＳと、サンプルＮＯ．２４ＰＳの炭素繊維に３０００℃の熱処理を行った後の炭素繊維のラマンスペクトルを示す。
【図１１】複合樹脂材をキシレンでエッチング処理したサンプル表面の電子顕微鏡写真である。
【図１２】図１１の拡大図である。
【図１３】高分子の結晶化の過程を示す説明図である。
【図１４】炭素繊維の配合量と結晶化時間との関係を示すグラフである。
【図１５】ＰＥＴの結晶面の広角Ｘ線回折測定曲線を示すグラフである。
【符号の説明】
１０ 炭素網層
１２ 堆積層
１４ 中心孔
１６ 凹凸[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a composite resin material using a crystalline resin and a method for producing the same.
[0002]
[Prior art]
Conventionally, in order to improve the crystallinity of a crystalline polymer (resin), an additive such as talc or benzylidene sorbitol has been added to the crystalline resin.
[0003]
[Patent Document 1]
JP-A-2000-109657
[Patent Document 2]
JP-A-11-029690 [Patent Document 3]
JP-A-10-176084
[Problems to be solved by the invention]
By the way, in order to improve the crystallinity by adding additives such as talc and benzylidene sorbitol to the crystalline resin, there is a problem that these additives must be added in a relatively large amount. This is because when the amount of the additive is small, the strength of the composite resin material is hardly improved. It is considered that the strength is not improved because the adhesion between the additive and the crystalline resin is not so good.
[0005]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a composite resin material capable of improving mechanical properties even by adding a small amount of an additive, and a method for producing the same.
[0006]
[Means for Solving the Problems]
The composite resin material according to the present invention is characterized in that the crystalline resin material is mixed with a carbon fiber formed by a vapor growth method in which a carbon net layer having a bottomless cup shape is laminated, and is subjected to a crystallization treatment, whereby the carbon The resin material around the fiber is crystallized, and a network structure is formed inside by the carbon fiber and the crystallized resin material.
[0007]
The carbon fiber is a carbon fiber in which the deposited layer on the surface is removed and the end face of the carbon mesh layer is exposed.
Further, the carbon fiber has a hollow shape with no nodes.
Further, the end faces of the carbon mesh layer on the inner and outer surfaces of the carbon fiber are exposed.
Further, the end face of the carbon mesh layer is exposed on the outer surface of 2% or more of the carbon fiber.
[0008]
Further, the surface portion of the carbon fiber where the end face of the carbon netting layer is exposed is characterized in that the end face is irregular and presents fine irregularities on the level of the size of atoms. This further improves the adhesion to the resin material.
It is preferable that the compounding ratio of the carbon fiber with respect to the crystalline resin material is 0.001 to 1 wt%.
The carbon fiber preferably has a diameter of 80 to 150 nm and an average length of several hundred nm to several tens of μm.
A general-purpose resin such as polyethylene terephthalate or polypropylene can be used as the crystalline resin material.
[0009]
Further, the method for producing a composite resin material according to the present invention is a method of heating and melting a mixture of a crystalline resin material and a carbon fiber formed by a vapor growth method in which a carbon network layer having a bottomless cup shape is laminated, and then having a melting point or lower. Holding the required temperature to crystallize the crystalline resin material.
Further, the method includes a molding step of molding a mixed material obtained by crystallizing the crystalline resin material into an arbitrary shape.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
The carbon fiber formed by the vapor growth method according to the present invention has a structure in which carbon net layers having a bottomless cup shape are laminated (hereinafter referred to as a herringbone structure carbon fiber).
An example of the manufacturing method will be described.
As the reactor, a known vertical reactor was used.
Benzene was used as a raw material, and was fed into the reactor by a hydrogen stream at a partial pressure of approximately 20 ° C. and a flow rate of 0.3 l / h into the chamber. The catalyst was ferrocene, vaporized at 185 ° C., and fed into the chamber at a concentration of approximately 3 × 10 ⁻⁷ mol / s. The reaction temperature was about 1100 ° C., the reaction time was about 20 minutes, and a herringbone structure carbon fiber having an average diameter of about 100 nm was obtained. By adjusting the flow rate of the raw material and the reaction temperature (changed according to the size of the reactor), a large number of carbon net layers having a bottomless cup shape are stacked, and the carbon net layer ranges from several tens nm to several tens μm. A hollow carbon fiber having no nodes (bridges) can be obtained.
The obtained carbon fiber has a diameter of about 80 to 150 nm and a length of about several tens to several hundreds μm, and the length may be adjusted to several μm to several tens of μm. The adjustment of the length can be performed by cutting the carbon fiber on which a large number of carbon net layers having a cup shape without a bottom are laminated by grinding, as described later.
[0011]
Hereinafter, first, the characteristics of the carbon fiber will be described.
FIG. 1 is a copy of a transmission electron micrograph of a carbon fiber having a herringbone structure produced by the vapor phase growth method, FIG. 2 is an enlarged view thereof, and FIG. 3 is a schematic view thereof.
As is clear from the figure, it can be seen that the deposited layer 12 in which amorphous surplus carbon is deposited is formed so as to cover the inclined carbon netting layer 10. 14 is a center hole.
By heating the carbon fiber on which such a deposited layer 12 is formed at a temperature of 400 ° C. or higher, preferably 500 ° C. or higher, more preferably 520 ° C. or higher and 530 ° C. or lower in the atmosphere for one to several hours, The deposited layer 12 is oxidized, thermally decomposed, and removed, and the end face (six-membered ring end) of the carbon mesh layer is partially exposed.
Alternatively, the deposited layer 12 can be removed by washing the carbon fiber with supercritical water, and the end face of the carbon mesh layer can be exposed.
Alternatively, the deposited layer 12 can be removed by immersing the carbon fiber in hydrochloric acid or sulfuric acid and heating the carbon fiber to about 80 ° C. while stirring with a stirrer.
[0012]
FIG. 4 is a copy of a transmission electron micrograph of a herringbone-structured carbon fiber heat-treated in the air at a temperature of about 530 ° C. for one hour as described above, FIG. 5 is an enlarged view thereof, and FIG. 6 is a further enlarged view thereof. FIG. 7 is a schematic diagram thereof.
As is clear from FIGS. 5 to 7, by performing the heat treatment as described above, a part of the deposited layer 12 is removed, and the end face (the six-membered carbon end) of the carbon mesh layer 10 is exposed. I understand. Note that the remaining deposited layer 12 is also almost completely decomposed, and it is considered that the remaining deposited layer 12 is merely attached. If the heat treatment is performed for several hours and the cleaning with supercritical water is also used, 100% of the deposited layer 12 can be removed.
As is apparent from FIG. 4, the carbon fiber 10 is formed by laminating a large number of carbon net surfaces having a cup shape without a bottom, and has a hollow shape at least in a range of several tens nm to several tens μm.
The inclination angle of the carbon mesh layer with respect to the center line is about 20 ° to 35 °.
[0013]
As is clear from FIGS. 6 and 7, the outer and inner surface portions where the end faces of the carbon netting layer 10 are exposed have irregular end faces, and are expressed in nm (nanometers), that is, at the atomic size level. It can be seen that fine irregularities 16 are exhibited. As shown in FIG. 2, although it is not clear before the removal of the deposited layer 12, the unevenness 16 appears by removing the deposited layer 12 by the above-described heat treatment.
The exposed end face of the carbon mesh layer 10 is easily linked to other atoms and has extremely high activity. This is because the oxygen-containing functional groups such as a phenolic hydroxyl group, a carboxyl group, a quinone-type carbonyl group, and a lactone group increase on the exposed end face of the carbon mesh layer while the deposited layer 12 is removed by the heat treatment in the air, It is considered that these oxygen-containing functional groups have high hydrophilicity and high affinity for various substances.
The anchor effect due to the hollow structure and the unevenness 16 is large.
[0014]
FIG. 8 shows Raman spectra of a carbon fiber having a herringbone structure (sample No. 24PS) after being heat-treated at 500 ° C., 520 ° C., 530 ° C., and 540 ° C. for 1 hour in the air.
By performing the heat treatment, but the deposition layer 12 is removed as shown in FIGS. 5 to 7, as is clear from the Raman spectra of FIG. 8, D peak (1360 cm ^-1) and G peak (1580 cm ^{- The} presence of ¹ ) indicates that this is a carbon fiber and a carbon fiber having no graphitized structure.
[0015]
That is, it is considered that the herringbone structure carbon fiber has a (grinded) turbostratic structure in which the carbon network plane is shifted (grind).
This turbostratic carbon fiber has a laminated structure in which each carbon hexagonal mesh plane is parallel, but each hexagonal mesh plane is shifted or rotated in the plane direction and has a crystallographic regularity. Does not have.
The feature of this turbostratic structure is that intercalation of other atoms or the like between layers is unlikely to occur. This is also one advantage. That is, since it is difficult for a substance to enter between the layers, as described above, atoms and the like are likely to be supported on the end face of the exposed and highly active carbon netting layer, and therefore, it is expected to function as an efficient carrier. You.
[0016]
FIG. 9 shows a sample NO. In which the heat treatment was performed to expose the end face of the carbon netting layer. 19PS and sample NO. 3 shows a Raman spectrum of a 24 PS carbon fiber.
FIG. 10 shows a sample No. having the end face of the carbon mesh layer exposed. 19PS and sample NO. 4 shows a Raman spectrum of a carbon fiber after a heat treatment (normal graphitization treatment) of 3000 ° C. is performed on a 24PS carbon fiber.
As shown in FIG. 10, it can be seen that the D peak does not disappear even if the carbon fiber with the end face of the carbon netting layer exposed is subjected to the graphitization treatment. This indicates that no graphitization has occurred even after the graphitization treatment.
Although not shown, even when X-ray diffraction was performed, it was found that the above-mentioned carbon fibers were not graphitized from the fact that no diffraction lines were emitted on the 112 plane.
[0017]
The fact that the graphitization is not performed even when the graphitization treatment is performed is considered to be because the deposition layer 12 that is easily graphitized is removed. It was also found that the remaining herringbone structure was not graphitized.
As described above, the absence of graphitization even in a high-temperature atmosphere means that it is thermally stable.
[0018]
The carbon fiber having a herringbone structure obtained as described above has a cup shape without a bottom, that is, a short fiber (long) in which tens of thousands to hundreds of thousands of unit carbon net layers having a cross-section in a U shape are laminated. (Several tens μm to several hundred μm).
The short fibers can be separated by adding water or a solvent in an appropriate amount and gently grinding with a pestle using a mortar.
That is, the short fibers (either having the deposited layer 12 formed thereon, or having the deposited layer 12 partially or completely removed, whichever may be used) are placed in a mortar, and the short fibers are mechanically gently ground with a pestle. .
By empirically controlling the processing time in a mortar, a carbon fiber having a length of several hundred nm to several tens μm can be obtained.
[0019]
At that time, the annular carbon network layer has a relatively high strength, and the layers between the carbon network layers are connected only by a weak van der Waals force.Therefore, the annular carbon network layer does not collapse. It will be separated between the carbon netting layers.
It is preferred that the short fibers are ground in a liquid nitrogen with a mortar. When the liquid nitrogen evaporates, the moisture in the air is absorbed and becomes ice, so that the short fibers are crushed with a pestle together with the ice, so that the mechanical stress is reduced and the separation between the unit fiber layers can be performed.
Industrially, the carbon fiber may be subjected to a grinding treatment by ball milling.
[0020]
The end face of the carbon netting layer 10 exposed as described above is easily linked to other atoms, has extremely high activity, and has a large surface energy. This is because, as described above, while the deposited layer 12 is removed by the heat treatment in the air, the exposed end face of the carbon netting layer has an oxygen-containing group such as a phenolic hydroxyl group, a carboxyl group, a quinone-type carbonyl group, or a lactone group. This is presumably because the number of functional groups increases, and these oxygen-containing functional groups are hydrophilic and have high affinity for various substances.
[0021]
In the present invention, the above-mentioned carbon fibers are mixed into a crystalline resin material to form a composite resin material.
The manufacturing process of the composite resin material is a process in which the powdery crystalline resin material and the carbon fiber formed by the vapor growth method in which a carbon net layer having a bottomless cup shape is laminated in a solvent, and from the mixture, It is characterized by including a drying step of evaporating the solvent, and a step of heating and melting the dried mixture, and maintaining the required temperature to crystallize the crystalline resin material.
Further, a composite material obtained by crystallizing the crystalline resin material can be formed into an arbitrary shape to obtain a composite resin material.
[0022]
As described above, the carbon fiber is mixed into the crystalline resin material, and the crystallization treatment is performed, whereby the resin material around the carbon fiber is crystallized, and the network is formed by the carbon fiber and the crystallized resin material. It has been found that a structure is formed, which increases the mechanical strength.
FIG. 11 and FIG. 12 show electron micrographs of the surface of the composite resin material when the composite resin material manufactured as described above is etched with xylene. It can be seen that the resin material that has not been crystallized is etched away by the xylene etching treatment, leaving a network structure.
Since this network structure is present in the composite resin material, the mechanical strength of the composite resin material is improved, and the conductivity and heat conduction characteristics are also improved by mixing carbon fibers.
[0023]
As described above, the formation of this network structure is based on the fact that the surface of the carbon fiber has an extremely high degree of activity because the end surface of the cup-shaped carbon network layer is exposed, so that the crystalline resin material around the carbon fiber is formed. This is probably because crystallization is promoted.
In addition, since the carbon fiber has an extremely thin rod shape with a diameter of nanometer unit, it is presumed that the exclusion volume effect promotes the crystallization of the crystalline resin material around the carbon fiber.
[0024]
It is said that crystal growth of a polymer requires nucleation for crystallization before crystallization, that is, in a crystallization induction period.
The process of polymer crystallization is shown in FIG.
1. Orientation of polymer chains (crystallization induction period)
2. Follow close packing by crystallization.
1. Is a kind of spinodal decomposition, and a concentration fluctuation needs to be formed in order for spinodal decomposition to occur.
Therefore, when rod-like particles (carbon fibers) having a large excluded volume effect are blended with the crystalline resin material, the resin concentration around the carbon fibers becomes smaller than that of other parts, causing concentration fluctuations and spinodal decomposition. When the crystallized resin material has a melting point or lower, it becomes a trans-type (polymer chains extend in a wavy or straight line, that is, orientate) with low energy, are gradually oriented, and eventually crystallize (FIG. 13). is there.
Such small-diameter rod-like particles can serve as nuclei for promoting crystallization of the crystalline resin material due to the excluded volume effect.
Incidentally, the excluded volume of a rod-shaped particle having a diameter of 50 nm and a length of 1 μm is about 2.5 times the excluded volume of a spherical particle having the same volume.
Rod-like particles having a diameter of 150 nm or less and an aspect ratio of 2 or more can be a nucleating agent for crystallization.
[0025]
In the present invention, the carbon fiber, the edge portion of the carbon mesh layer on the surface thereof is exposed and the activity is very high, and the large volume exclusion effect described above is combined with the carbon fiber. It is considered that the crystallization of the surrounding resin material is promoted to form a network structure. In addition, the crystallization speed is increased, and the production efficiency of the composite resin material is also improved.
In view of the excluded volume effect, the longer the carbon fiber, the better. However, if the length is too long, the carbon fibers become entangled with each other and form a cocoon ball, and when blended in a resin material, the resin does not penetrate, and voids (voids) are generated, which is preferable because strength is reduced. Absent.
Therefore, it is preferable to use a carbon fiber having a diameter of 80 to 150 nm and an average length of several hundred nm to several tens μm (aspect ratio is 2 or more, particularly preferably about 10 to 200).
Further, the mixing ratio of the carbon fiber to the crystalline resin material is not particularly limited, but as long as the dispersibility is good, an improvement in strength is recognized even with an addition amount of about 0.001 wt%. Further, the addition amount of the carbon fiber may be more than 1 wt%, but it is advantageous to make the addition amount 1 wt% or less from the viewpoint of cost. As described above, the compounding ratio of the carbon fiber to the crystalline resin material is preferably 0.001 to 1 wt%, and most preferably about 0.01 to 0.3 wt%.
[0026]
The method of mixing the crystalline resin material with the carbon fibers is not particularly limited.
For example, the above-mentioned carbon fibers may be added at the time of polymerizing the crystalline resin material.
Alternatively, when the crystalline resin material is a fluororesin, the powdery fluororesin and the carbon fiber may be mixed using alcohol as a solvent.
Alternatively, the powdery crystalline resin material and the carbon fiber may be kneaded using an extruder and mixed.
The mixture is heated and melted, and then maintained at a required temperature equal to or lower than the melting point in a molding die to crystallize the crystalline resin material and to form a composite resin material having a required shape.
[0027]
The crystalline resin material is not particularly limited, but general-purpose resins such as polyethylene terephthalate, polypropylene, and fluororesin can be suitably used.
When the crystalline resin material is polyethylene terephthalate, the mixed material containing the carbon fibers is melted at a temperature of about 280 ° C., and is then crystallized at a temperature of about 230 ° C., which is lower than the melting point, for about 10 minutes. It is preferable to set to.
When the crystalline resin material is polypropylene, the mixed material is melted at a temperature of about 190 ° C., and in the crystallization step, the mixed material is crystallized by holding the mixed material at a temperature of about 140 ° C. lower than the melting point temperature for about 10 minutes. It is preferable to set to.
[0028]
The composite resin material obtained in the present invention can be used for various applications.
1) The diaphragm can be suitably used for a diaphragm incorporated in a vibrator, a speaker, a microphone, or the like. This is advantageous because the strength of the diaphragm can be increased so that the diaphragm can be made thinner and the energy required for vibration can be reduced.
2) Wrapping film Wrapping film can be suitably used as a wrapping film for covering the surface layer of trains, automobiles, sporting goods, buses, buildings and the like. It is possible to make the film thinner by improving the film strength and thereby reduce the cost, and the handleability is improved by making the film thinner.
3) When used as a base material such as a product protection film, a packaging film, a sticker seal base material, a magnetic tape, etc., it is possible to reduce the thickness and thereby reduce the cost.
4) Extrusion molded products, injection molded products The mechanical strength and dimensional stability of these products can be improved.
It can be suitably used for electronic equipment parts, IT-related product parts, members of automobile parts and the like, members of micromachines and the like, members of precision instruments such as watches, members of fuel cell separators and the like.
5) FRTP (Fiber Reinforced Thermoplastic: Fiber Reinforced Thermoplastic)
By mixing the carbon fiber and promoting crystallization of the resin, the mechanical properties of FRTP can be improved, the weight can be reduced, the structure can be simplified, the dimensional stability, and the thermal expansion coefficient can be stabilized.
6) As a structural material for aircraft, objects that fly or fly in the air, equipment used in outer space, and as a member of medical equipment that wants to transmit radiation such as X-rays, and to reduce weight. It is suitable for housings of home electric appliances such as personal computers.
Further, it is suitable for a strength member of sporting goods such as a hanging rod, a shaft of a golf club, and a frame of a tennis racket.
It is also suitable for members of measuring instruments, exteriors of moving objects such as automobile motorcycles, members of structures, buildings and structures such as houses and buildings.
It is also suitable for interior / exterior and structural materials of ships such as leisure boats and yachts, submarines and the like.
7) The wire diameter can be reduced by improving the strength of the resin yarn.
8) It is possible to improve the film strength of a coating material such as a coating metal, wood, plastic, rubber, elastomer, inorganic substance, etc., and to make it thinner and impart strength.
[0029]
【Example】
Example 1
Powdered polyethylene terephthalate (PET) from which water has been removed by previously drying in a vacuum oven at 90 ° C. for 8 hours and carve LongCNT made by GS Icleos Co. (Diameter: 80 to 150 μm, aspect ratio adjusted to about 200) was measured so that the carbon fiber was 0.3 wt% with respect to PET. Hexafluoropropanol (HFIP) was added as a solvent thereto, and the solution was adjusted to have a solid content of 10% by weight. The solution was cast on a glass Petri dish and dried at room temperature. Next, the mixed material is melted at a temperature of about 280 ° C. to take a thermal history of the sample, completely remove the solvent and integrate, and then at a temperature of about 230 ° C. below the melting point temperature. Hold for 10 minutes to promote crystallization. Further, the obtained resin material was molded into an arbitrary shape by hot pressing to obtain a composite resin material.
[0030]
FIG. 14 is a graph showing the relationship between the blending amount of carbon fibers and the crystallization time. As is clear from FIG. 14, the crystallization time of the carbon fiber blended at 0.3 wt% was reduced to about half that of the carbon fiber blended without carbon fiber.
FIG. 15 shows a wide-angle X-ray diffraction measurement curve. As is clear from the figure, in the case where 0.3% by weight of carbon fiber was blended, the crystal plane spacing of PET was reduced by about 0.5% in each of the 011 plane, the 010 plane, the 110 plane, and the 100 plane.
Table 1 shows the results of measuring the yield point and the elastic modulus of a sample prepared by adding the above carbon fiber to PET at 0.15 wt% and preparing a sample having a length of 50 mm and a thickness of 3 mm by the above method. The yield point and the elastic modulus are improved by 209% and 251%, respectively, as compared with the sample of PET alone.
[0031]
[Table 1]

[0032]
Example 2
Powdered polypropylene (PP) which had been dried in a vacuum oven at 90 ° C. for 8 hours in advance to remove water, and carve LongCNT made by GS Icleos Co., Ltd. (80-150 μm, aspect ratio adjusted to about 200) was measured so that the carbon fiber was 0.3 wt% with respect to PP. Hexane was added as a solvent to the solution, and the solution was adjusted so that the solid content became 10 wt%. The solution was cast on a glass petri dish and dried at room temperature. Next, the mixed material is melted at a temperature of about 190 ° C. to take a thermal history of the sample, completely remove the solvent and integrate, and then at a temperature of about 140 ° C. below the melting point temperature. Hold for 10 minutes to promote crystallization. Further, the obtained resin material was molded into an arbitrary shape by hot pressing to obtain a composite resin material.
As in the case of Example 1, the one containing 0.3% by weight of carbon fiber was able to shorten the crystallization time by about half as compared with the one not containing carbon fiber. The crystal unit cell of PP decreased by about 0.5% in all of the a, b, and c axes. Further, the elastic modulus was improved by about 200%.
Further, as is apparent from the electron micrographs of the surface of the sample obtained by etching the composite resin material with xylene for about 10 seconds in FIGS. 11 and 12, the carbon fiber and the resin crystallized around the carbon fiber have a network structure. It can be seen that is formed.
[0033]
【The invention's effect】
As described above, according to the present invention, a crystalline resin material can be efficiently crystallized around carbon fibers in a short time by performing crystallization treatment by blending carbon fibers by a vapor growth method, At the same time as high-speed moldability, a composite resin that forms a network structure with carbon fiber and crystallized resin formed around the carbon fiber, has excellent mechanical strength, and also has improved electrical and thermal conductivity characteristics Material can be provided.
[Brief description of the drawings]
FIG. 1 is a copy of a transmission electron micrograph of a carbon fiber having a herringbone structure manufactured by a vapor phase growth method.
FIG. 2 is an enlarged view of FIG.
FIG. 3 is a schematic diagram of FIG. 2;
FIG. 4 is a copy of a transmission electron micrograph of a herringbone-structured carbon fiber that has been heat-treated in the air at a temperature of about 530 ° C. for one hour.
FIG. 5 is an enlarged view of FIG. 4;
FIG. 6 is a further enlarged view of FIG. 5;
FIG. 7 is a schematic diagram of FIG. 6;
FIG. 8 shows Raman spectra of a carbon fiber having a herringbone structure (sample No. 24PS) after being heat-treated at 500 ° C., 520 ° C., 530 ° C., and 540 ° C. for 1 hour in the air.
FIG. 9 shows a sample NO. In which an end face of a carbon netting layer was exposed by performing the above heat treatment. 19PS and sample NO. 3 shows a Raman spectrum of a 24 PS carbon fiber.
FIG. 10 shows a sample NO. 19PS and sample NO. 4 shows a Raman spectrum of a carbon fiber after heat treatment of 24 PS carbon fiber at 3000 ° C. FIG.
FIG. 11 is an electron micrograph of a sample surface obtained by etching a composite resin material with xylene.
FIG. 12 is an enlarged view of FIG. 11;
FIG. 13 is an explanatory view showing a process of crystallization of a polymer.
FIG. 14 is a graph showing the relationship between the blending amount of carbon fibers and the crystallization time.
FIG. 15 is a graph showing a wide-angle X-ray diffraction measurement curve of a crystal plane of PET.
[Explanation of symbols]
Reference Signs List 10 carbon netting layer 12 deposition layer 14 center hole 16 unevenness

Claims (14)

In the crystalline resin material, carbon fibers formed by a vapor growth method in which a carbon net layer having a bottomless cup shape is laminated are mixed and crystallized, whereby the resin material around the carbon fibers is crystallized. A composite resin material, wherein a network structure is formed inside the carbon fiber and the crystallized resin material. 2. The composite resin material according to claim 1, wherein the carbon fiber is a carbon fiber from which an end face of a carbon netting layer is exposed by removing a deposited layer on a surface. 3. The composite resin material according to claim 1, wherein the carbon fiber has a knotless hollow shape. The composite resin material according to claim 2, wherein the end faces of the carbon mesh layer on the inner and outer surfaces of the carbon fiber are exposed. The composite resin material according to any one of claims 2 to 4, wherein an end face of the carbon mesh layer is exposed on an outer surface of 2% or more of the carbon fiber. The surface portion where the end face of the carbon netting layer of the carbon fiber is exposed, the end face is irregular and presents fine irregularities on the level of the size of atoms. 2. The composite resin material according to claim 1. The composite resin material according to any one of claims 1 to 6, wherein a compounding ratio of the carbon fiber to the crystalline resin material is 0.001 to 1 wt%. The composite resin material according to claim 1, wherein the carbon fiber has a diameter of 80 to 150 nm and an average length of several hundred nm to several tens μm. The composite resin material according to any one of claims 1 to 8, wherein the crystalline resin material is polyethylene terephthalate or polypropylene. A mixture of a crystalline resin material and a carbon fiber formed by a vapor phase growth method in which a carbon net layer having a bottomless cup shape is laminated is heated and melted, and then the crystalline resin material is crystallized by maintaining the required temperature below the melting point. A method of producing a composite resin material. The method for producing a composite material according to claim 10, further comprising a molding step of molding a mixed material obtained by crystallizing the crystalline resin material into an arbitrary shape. The method for producing a composite resin material according to claim 10, wherein the carbon fiber is a carbon fiber from which a deposited layer on a surface is removed and an end face of a carbon mesh layer is exposed. The method for producing a composite resin material according to any one of claims 10 to 12, wherein a mixing ratio of the carbon fiber to the crystalline resin material is 0.001 to 1 wt%. The method for producing a composite resin material according to claim 10, wherein a carbon fiber having a diameter of 80 to 150 nm and an average length of several hundred nm to several tens μm is used as the carbon fiber.

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