JP2014000789A - Resin multilayered molded product and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin multilayer molded product which is high in orientation of a filler and high in mechanical strength, and a method for manufacturing the same.SOLUTION: There are provided a resin multilayer molded product 1 which includes a thermoplastic resin 11a and a filler 15 formed of a carbon material having a graphene structure and in which the filler 15 is scattered in the thermoplastic resin 11a and a plurality of resin composition layers 11 are laminated, wherein an angle formed between the longitudinal direction of each filler 15 and the direction of the average of the longitudinal direction of all fillers 15 is ±6° or less, and there is provided a method for manufacturing the resin multilayer molded product 1.

Description

  The present invention relates to a resin multilayer molded body in which a filler is dispersed in a thermoplastic resin and a method for producing the same, and in particular, a resin multilayer molded body in which a filler made of a carbon material having a graphene structure is dispersed in a thermoplastic resin, and It relates to the manufacturing method.

  In recent years, there has been a strong demand for resin moldings having high mechanical strength such as elastic modulus. As a material for a resin molded body having high mechanical strength, for example, a resin composite material in which a filler having a size of several nm to several tens of nm is dispersed in a thermoplastic resin has attracted attention. As such nano-level fillers, carbon carbon fibers, multi-walled carbon nanotubes, carbon fibers, exfoliated graphene, clay and the like are known.

  In order to effectively increase the mechanical strength of the resin molded body made of the resin composite material, it is necessary to orient the nano-level filler as described above in one direction in the resin molded body. For example, in Patent Document 1 below, a filler made of a carbon material is extruded into a fiber shape, and the filler made of the carbon material is mixed in the matrix by aligning and solidifying the direction of the fiber shaped product. A method for orienting is disclosed. Patent Document 2 below discloses a method for orienting a filler in a specific direction in a matrix by applying an electric field to a mixture of a filler made of a carbon material and a matrix, and a connected film in which the filler is oriented. It is disclosed.

US Pat. No. 7,186,092 JP 2006-312677 A

  However, in the resin molded body in which the nano-level filler is oriented by the methods of Patent Documents 1 and 2, the orientation of the filler is low. Therefore, there has been a problem that the mechanical strength of the resin molding cannot be sufficiently increased.

  An object of the present invention is to provide a resin multilayer molded article having high filler orientation and high mechanical strength and a method for producing the same.

  The resin multilayer molded body of the present invention includes a thermoplastic resin and a filler made of a carbon material having a graphene structure, and a plurality of resin composition layers in which the filler is dispersed in the thermoplastic resin are laminated. Yes. In the resin multilayer molded body of the present invention, the angle formed between the longitudinal direction of each of the fillers and the average direction of the longitudinal directions of all the fillers is ± 6 ° or less.

  In a specific aspect of the resin multilayer molded body of the present invention, the thickness of each of the plurality of resin composition layers is 1 to 3 times the thickness of the filler. In that case, since the said filler orientates in the direction parallel to the layer surface of the said resin composition layer, the orientation of the said filler can be improved more. Therefore, the mechanical strength of the resin multilayer molded body can be further increased.

  In another specific aspect of the resin multilayer molded body of the present invention, an aspect ratio of the carbon material having the graphene structure is in the range of 10 to 500. In that case, the reinforcement effect with respect to the external force applied to the direction which cross | intersects the lamination surface of the carbon material which has the said graphene structure can be heightened effectively.

  In another specific aspect of the resin multilayer molded body of the present invention, the carbon material having the graphene structure is at least one selected from the group consisting of exfoliated graphite, carbon fibers, and carbon nanotubes. In that case, exfoliated graphite has a nano size and a large specific surface area. Therefore, the mechanical strength of the resin multilayer molded body can be further increased.

  In still another specific aspect of the resin multilayer molded body of the present invention, the thermoplastic resin is at least one selected from the group consisting of polyolefin resins, polyamides, and ABS resins. In that case, the cost of the resin multilayer molded body can be reduced by using a polyolefin resin that is widely used.

  In still another specific aspect of the resin multilayer molded body of the present invention, the filler is contained in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin. In that case, the mechanical strength of the resin multilayer molded body can be increased more effectively.

  In another specific aspect of the resin multilayer molded body of the present invention, the resin multilayer molded body has a sheet shape. In that case, the resin multilayer molded body can be easily molded by laminating a plurality of sheet-shaped resin composition layers.

  The method for producing a resin multilayer molded body of the present invention includes a step of preparing a resin composite composition including the thermoplastic resin and the filler, and the filler is dispersed in the thermoplastic resin, and the resin composite composition A step of forming a laminate of the resin composition layer by co-extrusion molding, and a step of dividing the laminate and further laminating the divided laminate. Various resin multilayer molded products of the present invention can be produced by the production method described above.

  In the resin multilayer molded body of the present invention, the angle between the longitudinal direction of each filler made of a carbon material having a graphene structure and the average direction of the longitudinal directions of all the fillers is ± 6 ° or less, The orientation of the filler is high. Therefore, the mechanical strength of the resin multilayer molded body can be effectively increased.

  In the method for producing a resin multilayer molded body of the present invention, the laminate is formed by coextrusion molding, and then the laminate is divided, and the divided laminate is further laminated to form a multilayer. The orientation can be increased. Therefore, a resin multilayer molded body with high mechanical strength can be produced.

It is typical sectional drawing of the resin multilayer molded object in one Embodiment of this invention. It is typical sectional drawing of the resin multilayer molded object in other embodiment of this invention. It is a schematic diagram for demonstrating each process for obtaining a multilayer molded object in the case of manufacture of the resin compound molded object of this invention. It is a schematic perspective view which shows the shunt adapter used in laminating | stacking a some layer in forming the resin compound molded object which concerns on this invention.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

(Resin multilayer molded body 1)
FIG. 1 is a schematic cross-sectional view of a resin multilayer molded body of the present invention. In FIG. 1, hatching indicating a cross section is omitted in order to clarify the presence of the filler 15.

  As shown in FIG. 1, in the resin multilayer molded body 1, a plurality of resin composition layers 11 are laminated. Although the shape of the resin multilayer molded body 1 is not particularly limited, for example, a sheet shape is preferable. In that case, the resin multilayer molded body 1 can be easily molded by laminating a plurality of thin sheet-shaped resin composition layers 11.

  Although the thickness of the resin multilayer molded body 1 is not specifically limited, For example, it can be set as the range of 0.01-1.0 micrometer. Further, from the thickness of the resin composition layer 11, the number of layers of the resin multilayer molded body 1 necessary for making the resin multilayer molded body 1 a desired thickness may be determined.

  The number of laminated resin composition layers 11 in the resin multilayer molded body 1 is preferably 10 or more, more preferably 20 or more, and even more preferably 30 or more. By increasing the number of laminated resin composition layers 11, the mechanical strength of the resin multilayer molded body 1 can be further increased. Even when the thickness of the resin multilayer molded body 1 is the same, the mechanical strength of the resin multilayer molded body 1 increases as the number of the resin composition layers 11 stacked increases.

  The resin composition layer 11 includes a thermoplastic resin 11a, and a filler 15 is dispersed in the thermoplastic resin 11a. In the resin multilayer molded body 1 using the thermoplastic resin 11a, various molded products can be easily obtained by using various molding methods by heating.

  The thermoplastic resin 11a is not particularly limited, and various thermoplastic resins such as polyolefin, polyamide, polyester, polystyrene, polyvinyl chloride, polyvinyl acetate, and ABS resin can be used. Preferably, as the thermoplastic resin 11a, polyolefin resin such as polypropylene, polyethylene, random copolymer of ethylene and propylene, block copolymer of ethylene and propylene, copolymer of ethylene and α-olefin, polyamide At least one selected from the group consisting of ABS resins is used. More preferably, as the thermoplastic resin 11a, a polypropylene resin, that is, a propylene homopolymer, a copolymer of propylene and ethylene, or the like is used. The polypropylene resin is widely used in various resin moldings and is inexpensive. Moreover, the polypropylene resin can be easily molded at a relatively low temperature. Therefore, by using a polypropylene resin, the cost of the resin multilayer molded body 1 can be reduced, and the resin multilayer molded body 1 can be manufactured more easily.

  In the resin composition layer 11, a filler 15 made of a carbon material having a graphene structure is dispersed in the thermoplastic resin 11a. As the carbon material, preferably, at least one selected from the group consisting of graphite, exfoliated graphite, graphite, carbon fiber, and carbon nanotube can be used. More preferably, the carbon material is a laminate of a plurality of graphene sheets, that is, at least one selected from the group consisting of exfoliated graphite, carbon fibers, and carbon nanotubes. In the present invention, graphite refers to a laminate in which a number of graphene sheets are laminated. Exfoliated graphite is obtained by exfoliating graphite and refers to a graphene sheet laminate that is thinner than graphite. The number of graphene sheets laminated in exfoliated graphite may be less than that of graphite, but is usually about several layers to 200 layers, preferably about several layers to 10 layers. A thin graphene sheet is laminated on the exfoliated graphite, and the exfoliated graphite has a shape with a relatively large aspect ratio. Therefore, in the resin multilayer molded body of the present invention, when the filler 15 made of exfoliated graphite is uniformly dispersed in the thermoplastic resin 11a included in the resin composition layer 11, the laminated surface of the exfoliated graphite is used. The reinforcing effect against the external force applied in the direction intersecting with can be effectively enhanced.

  The preferable lower limit of the aspect ratio of the carbon material is 10, and the preferable upper limit is 500. In addition, an aspect ratio shall mean the ratio with respect to the thickness of the said carbon material of the largest dimension in the graphene sheet lamination surface direction of the said carbon material. If the aspect ratio of the carbon material is too low, the reinforcing effect against an external force applied in a direction intersecting the laminated surface may not be sufficient. On the other hand, even if the aspect ratio of the carbon material is too high, the effect may be saturated and a further reinforcing effect may not be expected. More preferably, the lower limit of the aspect ratio of the carbon material is 90, and the upper limit is 500.

  In the resin composition layer 11, all the fillers 15 in the thermoplastic resin 11 a are oriented in a certain direction, and the longitudinal direction of each filler 15 and the direction that is the average of the longitudinal directions of all the fillers 15. The formed angle is ± 6 ° or less. That is, the variation in the orientation angle of each filler 15 is small. Thereby, the orientation of the whole filler 15 is high. Therefore, the mechanical strength of the resin composition layer 11 is effectively increased. Therefore, mechanical strength such as tensile elastic modulus of the resin multilayer molded body 1 on which the resin composition layer 11 is laminated is increased.

  In this embodiment, the entire filler 15 is oriented in a direction parallel to the layer surface of the resin composition layer 11, but the orientation direction of the filler composed of the carbon material contained in the resin multilayer molded body of the present invention is as follows. It is not limited to the above direction. That is, the filler contained in the resin multilayer molded body of the present invention is an average of the longitudinal direction of each filler and the longitudinal direction of all the fillers as long as the entire filler has high orientation. As long as the angle formed with the direction is ± 6 ° or less, it may be oriented in any direction. But it is preferable that the said filler is orientated in the direction parallel to the layer surface of the resin composition layer of the said resin multilayer molded object. In that case, the mechanical strength of the resin composition layer and the resin multilayer molded body is further increased.

  The method for obtaining the angle is not particularly limited, but in the resin composition layer, a thin film slice of the central portion in the thickness direction is produced in the direction in which the filler is most oriented, the direction parallel to the resin flow direction during normal molding The thin film slice is obtained by observing the filler at a magnification of 500 to 10,000 times with a scanning electron microscope (SEM) and measuring the angle formed with the average direction in the longitudinal direction of the observed filler. be able to.

  The thickness of the resin composition layer 11 is not particularly limited, but it is preferable that the thickness be 1 to 3 times the thickness of the filler 15. Thereby, the filler 15 sandwiched between the upper layer surface and the lower layer surface of the resin composition layer 11 in the resin composition layer 11 is oriented in a direction parallel to the layer surface of the resin composition layer 11. Therefore, the mechanical strength such as the tensile elastic modulus of the resin composition layer 11 and the resin multilayer molded body 1 can be further increased. More preferably, the thickness of the plurality of resin composition layers 11 may be 1 to 2 times the thickness of the filler 15.

  The amount of the filler 15 contained in the thermoplastic resin contained in the resin composition layer 11 is preferably in the range of 1 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin 11a. By setting the amount of the filler 15 contained in the thermoplastic resin 11a within the above range, it is possible to obtain the resin multilayer molded body 1 having an increased mechanical strength such as a tensile elastic modulus. If the amount of the filler 15 contained in the thermoplastic resin 11a is less than 1 part by weight, the mechanical strength of the resin multilayer molded body 1 may not be sufficiently increased. When the amount of the filler 15 contained in the thermoplastic resin 11a exceeds 50 parts by weight, the rigidity of the resin multilayer molded body 1 becomes high and the resin multilayer molded body 1 may become brittle.

(Resin multilayer molded body 2)
FIG. 2 is a schematic cross-sectional view showing a resin multilayer molded body 2 according to a modification of the resin multilayer molded body 1 according to the embodiment of the present invention. In FIG. 2, hatching indicating a cross section is omitted to clarify the presence of the filler 15.

  As shown in FIG. 2, in the resin multilayer molded body 2, a plurality of first resin composition layers 21 and a plurality of second resin composition layers 22 are laminated. The first resin composition layer 21 corresponds to the resin composition layer 11 of the resin multilayer molded body 1. That is, the first resin composition layer 21 includes the thermoplastic resin 21a, and the filler 15 is dispersed in the thermoplastic resin 21a. In the present modification, the second resin composition layer 22 is made of the thermoplastic resin 22a, but may be composed mainly of the thermoplastic resin 22a. The main component means that at least half of the weight of the second resin composition layer 22 is composed of the weight of the thermoplastic resin 22 a included in the second resin composition layer 22.

  Like the resin multilayer molded body 2 of this modification, in the resin multilayer molded body of the present invention, the second resin composition layer 22 may be laminated together with the first resin composition layer 21. Even in this case, the resin multilayer molded body of the present invention can effectively increase the mechanical strength of the resin multilayer molded body because the orientation of the filler 15 in the first resin composition layer 21 is enhanced. it can.

  As the thermoplastic resins 21a and 22a, the same thermoplastic resins as those mentioned in the thermoplastic resin 11a of the resin multilayer molded body 1 can be used. Further, the thermoplastic resins 21a and 22a may be the same resin or different resins. When the thermoplastic resins 21a and 22a are the same resin, the adhesion between the first resin composition layer 21 and the second resin composition layer 22 can be enhanced. Moreover, when the thermoplastic resins 21a and 22a are different resins, for example, a first resin composition layer 21 including the thermoplastic resin 21a, and a second resin composition layer 22 including the thermoplastic resin 22a, By separating the functions, functionalities other than mechanical strength can be imparted to the resin multilayer molded body 1. For example, by using polyethylene oxide having a high gas barrier property as the thermoplastic resin 22a, the resin multilayer molded body 2 having a high gas barrier property can be obtained. Moreover, the resin multilayer molded object 2 with high impact resistance can be obtained by using ABS with high impact resistance as the thermoplastic resin 22a.

  In this modification, the second resin composition layer 22 does not include a filler made of a carbon material having a graphene structure, but the second resin composition layer 22 contains a filler made of a carbon material having a graphene structure. You may go out. However, the smaller the amount of the filler made of the carbon material having a graphene structure contained in the second resin composition layer 22, the less the mechanical strength of the resin multilayer molded body 2 is reduced. The amount of filler used can be reduced efficiently.

  The thickness of the second resin composition layer 22 can be approximately the same as the thickness of the first resin composition layer 21. In addition, from the thickness of the 1st resin composition layer 21 and the 2nd resin composition layer 22, the total number of layers of the resin multilayer molded object required in order to make the resin multilayer molded object 2 desired thickness is determined. Also good.

(Method for producing resin multilayer molded body)
Next, an embodiment of a method for producing the resin multilayer molded body 1 of the present invention will be described.

  First, a filler 15 made of a carbon material having a graphene structure is uniformly dispersed in the thermoplastic resin 11a to obtain a resin composition in which the filler 15 is uniformly dispersed in the thermoplastic resin 11a. In the dispersion method, for example, the thermoplastic resin 11a and the filler 15 are kneaded under heating using a twin screw kneader or a twin screw extruder such as a plast mill, so that the filler 15 becomes the thermoplastic resin 11a. The above resin composition uniformly dispersed therein can be obtained.

  In addition, when obtaining the resin composition in which the filler 15 made of exfoliated graphite is uniformly dispersed in the thermoplastic resin 11a, the above resin is also obtained by a method of kneading the expanded graphite with the thermoplastic resin 11a under heating. A composition can be obtained. In expanded graphite, the interlayer distance of graphite is widened. However, expanded graphite is separated into a plurality of exfoliated graphite by melting and kneading under heating with a thermoplastic resin, and the exfoliated graphite is homogeneous in the molten kneaded product. To be distributed. The expanded graphite can be obtained by increasing the interlayer distance of graphite by an electrochemical method in which electrolyte ions such as nitrate ions are inserted between the graphite layers.

  Next, the resin composition is coextruded to obtain a laminate of two or more layers in which the resin composition layer 11 made of the thermoplastic composition is laminated. The method for obtaining the laminate is not particularly limited, and examples thereof include a wet lamination method, a dry lamination method, a melt heat press lamination method, an extrusion coating method, a multilayer melt extrusion method, a hot melt lamination method, and a heat lamination method.

  Preferably, as the production method, a multilayer melt extrusion method that facilitates production of the resin multilayer molded body 1 of the present invention can be used. Examples of the multilayer melt extrusion method include a multi-manifold method and a feed block method. Specifically, the resin composition is introduced into both the first extruder and the second extruder, and the resin composition is extruded simultaneously from the first extruder and the second extruder. The resin composition extruded from the first extruder and the second extruder is sent to a feed block. In the feed block, the resin composition extruded from the first extruder and the second extruder joins. Thereby, the laminated body by which the resin composition layer 11 containing the said resin composition was laminated | stacked can be obtained.

  Next, the laminated body is transferred to a multilayer forming block and multi-layered in the multilayer forming block to obtain a resin multilayer molded body 1 having 10 or more layers.

  An example of a method for obtaining a resin composite molded body composed of a laminate of 10 layers or more will be described with reference to FIG. As shown in FIG. 3, the laminated body 31 formed by laminating the first layer 32 and the second layer 33 is extruded from an extruder. In the extrusion direction, the laminate 31 is divided into a plurality of pieces in the step I. That is, the laminated body 31 is divided along a plurality of surfaces that are parallel to the extrusion direction of the laminated body 31 and are perpendicular to the laminated surface. In this way, divided laminates 31A, 31B, 31C, 31D are obtained.

  Next, in step II, the stacked bodies 31A to 31D obtained by the division using a diversion adapter or the like are moved so as to be aligned in the stacking direction. Here, the laminated body 31B, the laminated body 31D, the laminated body 31A, and the laminated body 31C are arranged in this order from the top.

  Thereafter, in step III, the stacked body 31B, the stacked body 31D, the stacked body 31A, and the stacked body 31C are expanded in a direction parallel to the stacked surface. Next, in the IV process, the expanded laminates 31A to 31D are superposed and then compressed in a direction perpendicular to the laminate surface. In this way, an eight-layer laminate 34 can be obtained. By repeating these steps I to IV, a multilayer molded article having 10 or more layers can be obtained.

  An example of the diversion adapter is shown in FIG. In the shunt adapter shown in FIG. 4, the stacked bodies 36 </ b> A to 36 </ b> D are stacked according to the steps I to IV shown in FIG. 3 described above. A multilayer molded body can be obtained by using a plurality of stages of the diversion adapter.

  The multilayer molding is not limited to the method of the present embodiment as described above, and can be performed by an appropriate multilayering method and apparatus. For example, the laminated body may be multilayered by repeatedly folding back to obtain a resin multilayer molded body 1 having 10 or more layers.

  In the multilayer molding, the thickness of the resin composition layer 11 is preferably thinned to 1 to 3 times the thickness of the filler 15. Thereby, the filler 15 is oriented in a direction parallel to the layer surface of the resin composition layer 11. Thereby, mechanical strength such as tensile elastic modulus of the obtained resin multilayer molded body 1 can be further increased. Moreover, the resin multilayer molded body 1 having a high mechanical strength and a large thickness can be obtained by laminating a large number of the resin composition layers 11 formed thin as described above.

  The resin multilayer molded body 2 in the modified example of the present invention can be manufactured by the above manufacturing method using the second thermoplastic resin 22a together with the resin composition. Specifically, the resin composition is introduced into the first extruder, the second thermoplastic resin 22a is introduced into the second extruder, and merged in the feed block. The laminated body by which the 1st resin composition layer 21 containing and the 2nd resin composition layer 22 containing the thermoplastic resin 22a were laminated | stacked can be obtained. Then, the resin multilayer molded body 2 can be obtained by multilayer molding of the laminate.

  Hereinafter, the present invention will be clarified by giving specific examples of the present invention. In addition, this invention is not limited to the following Example.

(Flaky graphite)
Exfoliated graphite used in Examples 2 to 4 and Comparative Examples 2 to 4 was produced by the following method.

  2.5 g of graphite single crystal powder was supplied to 115 ml of 65 wt% concentrated sulfuric acid, and the resulting mixture was stirred while being cooled in a 10 ° C. water bath. Next, the mixture was stirred while gradually adding 15 g of potassium permanganate to the mixture obtained by stirring the graphite single crystal powder and concentrated sulfuric acid, and the mixture was reacted at 35 ° C. for 30 minutes.

  Next, 230 g of water was gradually added to the reaction mixture, and the mixture was reacted at 98 ° C. for 15 minutes. Thereafter, 700 g of water and 45 g of 30% by weight of hydrogen peroxide were added to the reaction mixture to stop the reaction. After centrifuging the mixture at a rotational speed of 14000 rpm for 30 minutes, the obtained graphite oxide was thoroughly washed with 5% by weight of diluted hydrochloric acid and water and then dried. The obtained graphite oxide is dispersed in water in an amount of 2 mg / ml, and then ultrasonic waves are irradiated to the graphite oxide for the following time using an ultrasonic cleaner at 45 kHz and 600 W. Thus, exfoliated graphite was exfoliated and fragmented between the layer interfaces to obtain exfoliated graphite in which the layer surface was oxidized. Hydrazine was added to exfoliated graphite in which the obtained layer surface was oxidized and reduced for 10 minutes. Reduced exfoliated graphite was classified using filters with pore sizes of 100 μm, 50 μm, 20 μm, and 10 μm (all manufactured by ADVANTEC) in order from the filter with the largest pore size. Thereafter, the classified exfoliated graphite was dried to obtain exfoliated graphite.

(Manufacture of multilayer molded products)
The multilayer molded articles of Examples 1 to 10 were produced by the following method.

  The material of the resin composition layer was extruded with two extruders to form a resin composition layer. The extruded resin composition layer was laminated in a feed block to form a laminate. Next, in the multilayer forming block, the laminate was repeatedly folded to obtain a multilayer molded body.

Example 1
100 parts by weight of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec EA9), graphite (manufactured by SEC Carbon Co., Ltd., high-purity graphite, grade “SNO-5”, maximum dimension in the plane direction of the layer surface of the graphene layer, 5 μm, lamination Several 1500 layers and an aspect ratio of 10) 40 parts by weight were melt-kneaded at 200 ° C. with an extruder to produce a resin composite composition.

  Next, using the resin composite composition as a material for the resin composition layer, the multilayer forming block is adjusted so that the thickness per layer is 1000 nm (2.0 times the exfoliated graphite), and the manufacturing is performed. A sheet-like multilayer molded body having a thickness of 300 μm was produced by the method.

(Example 2)
Exfoliated graphite was obtained by the above production method with an ultrasonic irradiation time of 5 minutes. The exfoliated graphite had a maximum dimension in the plane direction of the layer surface of the graphene layer of 5 μm, a stacking number of 180 layers, and an aspect ratio of 90.

  Next, 100 parts by weight of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec EA9) and 40 parts by weight of exfoliated graphite were melt-kneaded at 200 ° C. with an extruder to produce a resin composite composition. .

  Next, using the resin composite composition as a material for the resin composition layer, the multilayer forming block is adjusted so that the thickness per layer is 150 nm (2.5 times the exfoliated graphite), and the manufacturing is performed. A sheet-like multilayer molded body having a thickness of 300 μm was produced by the method.

(Example 3)
Exfoliated graphite was obtained by the above production method with an ultrasonic irradiation time of 10 minutes. The exfoliated graphite had a maximum dimension in the surface direction of the layer surface of the graphene layer of 5 μm, a stacking number of 90 layers, and an aspect ratio of 180.

  Next, 100 parts by weight of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec EA9) and 40 parts by weight of exfoliated graphite were melt-kneaded at 200 ° C. with an extruder to produce a resin composite composition. .

  Next, using the resin composite composition as a material for the resin composition layer, the multilayer forming block is adjusted so that the thickness per layer is 100 nm (3.3 times the exfoliated graphite), and the manufacturing is performed. A sheet-like multilayer molded body having a thickness of 300 μm was produced by the method.

Example 4
Exfoliated graphite was obtained by the above production method with an ultrasonic irradiation time of 15 minutes. The exfoliated graphite had a maximum dimension of 5 μm in the surface direction of the layer surface of the graphene layer, 20 laminated layers, and an aspect ratio of 300.

  Next, 100 parts by weight of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec EA9) and 40 parts by weight of exfoliated graphite were melt-kneaded at 200 ° C. with an extruder to produce a resin composite composition. .

  Next, using the resin composite composition as a material for the resin composition layer, the multilayer forming block is adjusted so that the thickness per layer is 25 nm (3.0 times the exfoliated graphite), and the manufacturing is performed. A sheet-like multilayer molded body having a thickness of 300 μm was produced by the method.

(Comparative Examples 1-4)
The resin composite products obtained in Examples 1 to 4 were subjected to single layer extrusion using an extruder, thereby obtaining a sheet-shaped single layer molded body having a thickness of 300 μm.

(Example 5)
In the same manner as in Example 2 except that 20 parts by weight of carbon nanotubes (trade name “CTUBE-100” manufactured by CNT) was used instead of exfoliated graphite, the above multilayer was formed so that the thickness per layer was 150 nm. A forming block was prepared, and a sheet-like multilayer molded body having a thickness of 300 μm was produced by the above production method.

(Comparative Example 5)
The resin composite product obtained in Example 5 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

(Example 6)
The thickness per layer was 150 nm in the same manner as in Example 2 except that 20 parts by weight of carbon nanofiber (trade name “CNF-T” manufactured by MD Nanotech) was used instead of exfoliated graphite. The multilayer forming block was prepared, and a sheet-shaped multilayer molded body having a thickness of 300 μm was manufactured by the manufacturing method.

(Comparative Example 6)
The resin composite product obtained in Example 6 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

(Example 7)
Instead of polypropylene, polyamide (trade name “1300S” manufactured by Asahi Kasei Co., Ltd., flexural modulus: 2.7 GPa, linear expansion coefficient: 8 × 10 ⁻⁵ / K) 100 parts by weight, graphite (manufactured by SEC Carbon Co., high purity) Per layer, similar to Example 1 except that 20 parts by weight of graphite, grade “SNO-5”, maximum dimension 5 μm in the plane direction of the layer surface of the graphene layer, 1500 layers, aspect ratio 10) are used. The multilayer forming block was prepared so that the thickness of the sheet became 1000 nm, and a sheet-like multilayer molded body having a thickness of 300 μm was manufactured by the manufacturing method.

(Comparative Example 7)
The resin composite product obtained in Example 7 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

(Example 8)
Example 1 was used except that 100 parts by weight of polyamide and 20 parts by weight of exfoliated graphite (the maximum dimension in the plane direction of the graphene layer was 5 μm, the number of layers was 90 layers, and the aspect ratio was 180) were used. The multilayer forming block was adjusted so that the thickness per layer was 150 nm, and a sheet-like multilayer molded body having a thickness of 300 μm was manufactured by the manufacturing method.

(Comparative Example 8)
The resin composite product obtained in Example 8 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

Example 9
Instead of polypropylene, ABS (trade name “S210B” manufactured by UMG ABS Co., Ltd., flexural modulus: 2.3 GPa, linear expansion coefficient: 7 × 10 ⁻⁵ / K) and 100 parts by weight of graphite (manufactured by SEC Carbon Co., Ltd., high One layer as in Example 1 except that 20 parts by weight of pure graphite, grade “SNO-5”, the maximum dimension in the plane direction of the layer surface of the graphene layer was 5 μm, the number of layers was 1500, and the aspect ratio was 10). The multilayer forming block was prepared so that the per-thickness was 1000 nm, and a sheet-shaped multilayer molded body having a thickness of 300 μm was manufactured by the manufacturing method.

(Comparative Example 9)
The resin composite product obtained in Example 9 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

(Example 10)
Except for using 100 parts by weight of ABS and 20 parts by weight of exfoliated graphite (the maximum dimension in the surface direction of the graphene layer is 5 μm, the number of layers is 90 layers, and the aspect ratio is 180), the same as in Example 1, The multilayer forming block was prepared so as to have a thickness of 150 nm per layer, and a sheet-like multilayer molded body having a thickness of 300 μm was manufactured by the manufacturing method.

(Comparative Example 10)
The resin composite product obtained in Example 10 was subjected to single layer extrusion molding with an extruder to obtain a sheet-shaped single layer molded body having a thickness of 300 μm.

(Evaluation of Examples and Comparative Examples)
About the multilayer molded object obtained by Examples 1-10 and the single layer molded object obtained by Comparative Examples 1-10, the tensile elasticity modulus and the orientation angle of the filler were evaluated by the following procedures.

(1) Tensile Elastic Modulus According to JIS K7113, the tensile elastic modulus of the multilayer molded body obtained in Examples 1 to 10 and the single layer molded body obtained in Comparative Examples 1 to 10 was measured. The results are shown in Table 1.

(2) Orientation angle of filler The multilayer molded body obtained in Examples 1-10 and the single-layer molded body obtained in Comparative Examples 1-10 were cut. The cut surface was photographed with a scanning electron microscope (SEM), and the angle between the longitudinal direction of each filler and the average direction of the longitudinal directions of all the fillers was measured from the image of the cut surface. . The results are shown in Table 1.

  As is clear from Table 1, in the multilayer molded articles of Examples 1 to 10, the orientation angle of the filler is small as compared with the single-layer molded articles of Comparative Examples 1 to 10. That is, it can be seen that the variation in the orientation angle of each filler is small, and the whole filler is oriented in a more constant direction. This is considered that the orientation of the whole filler was improved by multilayering the molded articles of Examples 1 to 10.

  In addition, it can be seen that the multilayer molded articles of Examples 1 to 10 have higher tensile elastic modulus than the single-layer molded articles of Comparative Examples 1 to 10. This is considered that the mechanical strength of the multilayer molded body was increased by reducing the orientation angle of the filler and increasing the orientation of the entire filler.

DESCRIPTION OF SYMBOLS 1 ... Resin multilayer molded object 2 ... Resin multilayer molded object 11 ... Resin composition layer 11a ... Thermoplastic resin 15 ... Filler 21 ... 1st resin composition layer 22 ... 2nd resin composition layer 21a, 22a ... Thermoplastic Resin 31 ... Laminated body 31A, 31B, 31C, 31D ... Laminated body 32 ... First layer 33 ... Second layer 34 ... Laminated body 36A, 36B, 36C, 36D ... Laminated body

Claims (8)

A resin multilayer molded body comprising a thermoplastic resin and a filler made of a carbon material having a graphene structure, wherein a plurality of resin composition layers in which the filler is dispersed in the thermoplastic resin are laminated,
A resin multilayer molded body in which an angle formed between the longitudinal direction of each filler and the average direction of all the fillers is ± 6 ° or less.   The resin multilayer molded body according to claim 1, wherein the thickness of each of the plurality of resin composition layers is 1 to 3 times the thickness of the filler.   The resin multilayer molded body according to any one of claims 1 to 2, wherein an aspect ratio of the carbon material having the graphene structure is in a range of 10 to 500.   The resin multilayer molded body according to any one of claims 1 to 3, wherein the carbon material having a graphene structure is at least one selected from the group consisting of exfoliated graphite, carbon fibers, and carbon nanotubes.   The resin multilayer molded body according to any one of claims 1 to 4, wherein the thermoplastic resin is at least one selected from the group consisting of a polyolefin resin, a polyamide, and an ABS resin.   The resin multilayer molded body according to any one of claims 1 to 5, wherein the filler is contained at a ratio of 1 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin.   The resin multilayer molded body according to any one of claims 1 to 6, wherein the resin multilayer molded body has a sheet shape. It is a manufacturing method of the resin multilayer molded object according to any one of claims 1 to 7,
Preparing a resin composite composition comprising the thermoplastic resin and the filler, wherein the filler is dispersed in the thermoplastic resin;
Forming a laminate of the resin composition layer by co-extrusion molding the resin composite composition;
Dividing the laminate, and further laminating the divided laminate. A method for producing a resin multilayer molded body.

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