JP2012224815A - Method for producing carbon fiber composite material, carbon fiber composite material and oil field apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a carbon fiber composite material, and a carbon fiber composite material using carbon nanofiber and carbon black, and to provide an oil field apparatus using a carbon fiber composite material.SOLUTION: The method for producing a carbon fiber composite material includes a step (a), a step (b) and a step (c). In the step (a), after carbon nanofiber 80 is mixed in a first elastomer 30, the mixture is refined at 0°C to 50°C by use of open rolls 2 having a roll nip d of 0.5 mm or less to obtain a first composite elastomer. In the step (b), carbon black is mixed in a second elastomer to obtain a second composite elastomer. In the step (c), the first composite elastomer is mixed with the second composite elastomer to obtain a carbon fiber composite material.

Description

  The present invention relates to a method for producing a carbon fiber composite material using carbon nanofibers, a carbon fiber composite material, and an oil field device.

  Conventionally, it has been difficult to fibrillate carbon nanofibers that tend to aggregate and disperse them uniformly in a matrix such as an elastomer. However, by applying a strong shearing force to the elastomer, the elasticity and viscosity of the elastomer An epoch-making method for producing a carbon fiber composite material has been proposed in which carbon nanofibers can be disentangled and dispersed uniformly in an elastomer by chemical interaction with the fibers (see, for example, Patent Document 1). .

  Furthermore, when a change in the composite material of multi-walled carbon nanotubes and natural rubber immersed in a solvent was examined, multi-walled carbon nanotubes that were defibrated and dispersed uniformly were continuously at a high filling rate of 16% by mass or more. It has been found that a three-dimensional structure (cellation) is formed (for example, see Non-Patent Document 1). This continuous three-dimensional structure is formed by an interfacial phase of multi-walled carbon nanotubes and rubber bonded to the surface thereof, and has been found to have high elastic modulus and high heat resistance. However, the use of a large number of multi-walled carbon nanotubes tends to reduce processability and increase costs.

  In addition, a carbon fiber composite material has been proposed in which an appropriate amount of carbon nanofibers and carbon black is blended with an elastomer so that the thermal expansion is small and stable over a wide temperature range (for example, see Patent Document 2). Such a carbon fiber composite material can reduce the compounding quantity of carbon nanofiber, when carbon nanofiber and carbon black cooperate and form a continuous three-dimensional structure.

JP 2005-97525 A JP 2007-39649 A

Carbon TANSO 2010 No. 244 147-152 “Swelling and interface analysis of multi-walled carbon nanotube / natural rubber composites”

  An object of the present invention is to provide a method for producing a carbon fiber composite material using carbon nanofibers and carbon black, a carbon fiber composite material, and an oil field device using the carbon fiber composite material.

The method for producing a carbon fiber composite material according to the present invention includes:
(A) a step of obtaining a first composite elastomer by mixing carbon nanofibers with the first elastomer and then performing thinning at 0 ° C. to 50 ° C. using an open roll having a roll interval of 0.5 mm or less; ,
A step (b) of obtaining a second composite elastomer by mixing carbon black with the second elastomer;
A step (c) of obtaining a carbon fiber composite material by mixing the first composite elastomer and the second composite elastomer;
including.

  According to the method for producing a carbon fiber composite material according to the present invention, a carbon fiber composite material having improved shear fatigue life can be obtained. Moreover, according to the method for producing a carbon fiber composite material according to the present invention, a carbon fiber composite material having improved tensile strength and breaking elongation can be obtained. Moreover, according to the manufacturing method of the carbon fiber composite material concerning this invention, the fall of workability can be prevented by suppressing the increase in the compounding quantity of carbon nanofiber, and it can be excellent in cost effectiveness.

In the method for producing a carbon fiber composite material according to the present invention,
In the step (a), 60 parts by mass or more and 100 parts by mass or less of carbon nanofibers can be blended with respect to 100 parts by mass of the first elastomer.

In the method for producing a carbon fiber composite material according to the present invention,
The first composite elastomer has a first spin-spin relaxation time (T2n) of 100 to 3000 μsec in an uncrosslinked body, as measured at 150 ° C. by a Hahn echo method using pulsed NMR, The spin-spin relaxation time (T2nn) can be absent.

In the method for producing a carbon fiber composite material according to the present invention,
In the step (b), 20 parts by mass or more and 150 parts by mass or less of carbon black can be blended with respect to 100 parts by mass of the second elastomer.

In the method for producing a carbon fiber composite material according to the present invention,
The first elastomer and the second elastomer may be natural rubber.

  The carbon fiber composite material concerning this invention can be obtained with the manufacturing method of the said carbon fiber composite material.

  The oil field device according to the present invention can use the carbon fiber composite material.

It is a figure which shows a process (a) typically. It is a figure which shows a process (a) typically. It is a figure which shows a process (a) typically. It is a figure which shows a process (b) typically. It is a figure which shows a process (b) typically. It is a figure which shows a process (b) typically. It is a figure which shows a process (c) typically. It is a figure which shows a process (c) typically. It is sectional drawing which shows typically the logging apparatus for underground use concerning one Embodiment. It is sectional drawing which shows typically the logging apparatus for the seabed use concerning one Embodiment. It is a graph showing the tensile strength with respect to the hardness of Examples 1-2 and Comparative Examples 1-3. It is a graph showing the breaking elongation with respect to the hardness of Examples 1-2 and Comparative Examples 1-3. It is a graph showing the shear fatigue life with respect to the hardness of Examples 1-2 and Comparative Examples 1-3.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  In the method for producing a carbon fiber composite material according to one embodiment of the present invention, after mixing carbon nanofibers with the first elastomer, an open roll having a roll interval of 0.5 mm or less is used. (A) to obtain a first composite elastomer by thinning through, a step (b) to obtain a second composite elastomer by mixing carbon black with the second elastomer, and the first composite elastomer, Mixing the second composite elastomer to obtain a carbon fiber composite material (c).

  FIGS. 1-3 is a figure which shows typically the process (a) of the manufacturing method of the carbon fiber composite material which concerns on one embodiment. 4-6 is a figure which shows typically the process (b) of the manufacturing method of the carbon fiber composite material which concerns on one Embodiment. FIGS. 7-8 is a figure which shows typically the process (c) of the manufacturing method of the carbon fiber composite material which concerns on one Embodiment.

  A process (a) can be performed using the open roll 2 as shown in FIGS. 1-3, for example. The first roll 10 and the second roll 20 in the two-roll open roll 2 are arranged at a predetermined interval d, for example, 0.5 mm to 1.5 mm, and the rotational speed V1, in the direction indicated by the arrow. V2 rotates forward or backward.

  First, as shown in FIG. 1, the first elastomer 30 wound around the first roll 10 is masticated, and the molecular chain of the elastomer is appropriately cut to generate free radicals. Free radicals of the elastomer generated by mastication are likely to be combined with carbon nanofibers.

  Next, as shown in FIG. 2, a plurality of carbon nanofibers 80 are put into the bank 34 of the first elastomer 30 wound around the first roll 10 and kneaded to obtain the first mixture 36. Can do. The step of obtaining the first mixture 36 of FIGS. 1 to 2 in the step (a) is not limited to the open roll method, and for example, a closed kneading method or a multi-screw extrusion kneading method can be used.

  Further, as shown in FIG. 3, the roll interval d between the first roll 10 and the second roll 20 is set to, for example, 0.5 mm or less, more preferably 0 to 0.5 mm, and in FIG. The obtained 1st mixture 36 can be thrown into the open roll 2, and thinning can be performed once to several times. For example, the thinning can be performed about 1 to 10 times. When the surface speed of the first roll 10 is V1 and the surface speed of the second roll 20 is V2, the ratio of the surface speeds (V1 / V2) in thinness is 1.05 to 3.00. Furthermore, it is preferable that it is 1.05-1.2. By using such a surface velocity ratio, a desired shear force can be obtained. The first composite elastomer 50 extruded from between the narrow rolls as described above is further greatly deformed as shown in FIG. 3 by the restoring force due to the elasticity of the first elastomer 30, and at that time, together with the first elastomer 30, The fiber moves greatly. The first composite elastomer 50 obtained through thinning is rolled with a roll and dispensed into a sheet having a predetermined thickness, for example, 100 μm to 500 μm. In this thinning process, in order to obtain as high a shearing force as possible, the roll temperature can be set to 0 to 50 ° C., for example, and further set to a relatively low temperature of 5 to 30 ° C. it can. The actually measured temperature of the first elastomer 30 can also be adjusted to 0 to 50 ° C., and further adjusted to 5 to 30 ° C. By adjusting to such a temperature range, the carbon nanofibers can be dispersed using the elasticity of the first elastomer 30. Due to the shearing force thus obtained, a high shearing force acts on the first elastomer 30 and the aggregated carbon nanofibers are separated from each other so as to be pulled out one by one to the molecules of the first elastomer. , Dispersed in the first elastomer 30. In particular, since the first elastomer 30 has elasticity, viscosity, and chemical interaction with the carbon nanofibers, the carbon nanofibers can be easily dispersed. And the 1st composite elastomer 50 excellent in the dispersibility and dispersion stability of carbon nanofiber (it is hard to re-aggregate carbon nanofiber) can be obtained.

  More specifically, when the first elastomer and the carbon nanofibers are mixed with an open roll, the first elastomer having viscosity penetrates into the carbon nanofibers, and the specific molecules of the first elastomer are specified. The part binds to the highly active part of the carbon nanofiber by chemical interaction. When the surface of the carbon nanofibers is moderately high by, for example, oxidation treatment, it can be easily bonded to the molecules of the first elastomer. Next, when a strong shearing force acts on the first elastomer, the carbon nanofibers move with the movement of the molecules of the first elastomer, and further aggregate due to the restoring force of the first elastomer due to elasticity after shearing. The carbon nanofibers that have been separated are separated and dispersed in the first elastomer. In particular, the open roll method is preferable because it can measure and manage not only the roll temperature but also the actual temperature of the mixture.

  In the step (a), 60 parts by mass or more and 100 parts by mass or less of carbon nanofibers can be blended with respect to 100 parts by mass of the first elastomer, and can be 70 parts by mass or more and 90 parts by mass or less. In particular, it can be 75 parts by mass or more and 85 parts by mass or less. Considering the first composite elastomer consisting of only the first elastomer and the carbon nanofibers, if the carbon nanofibers are 60 parts by mass or more, the compounding amount of the carbon nanofibers in the first composite elastomer is about 28 masses. % Or more. By uniformly dispersing a predetermined amount or more of carbon nanofibers in the first composite elastomer, a three-dimensional network chain structure is formed by the carbon nanofibers and the interface phase formed around the carbon nanofibers. The region of elastomer surrounded by the network chain forms a small cell structure. By increasing the amount of carbon nanofiber blended, a small cell structure with small cell structures gathered together, and the carbon nanofibers that connect the small assemblies and the interfacial phase are band-shaped. (Tai) A structure is formed. It is considered that the small aggregate of cell structure and the tie structure greatly affect the physical strength and chemical strength (resistance to chemicals) of the first composite elastomer. By increasing the compounding amount of the carbon nanofibers in the first elastomer, the small aggregates and tie structures are increased, and the physical strength and chemical strength of the first composite elastomer can be improved. When about 60 parts by mass (about 37% by mass) of carbon nanofibers are contained in the first composite elastomer, about 80% of the total is considered to be a cell structure, and when the carbon nanofibers exceed 80 parts by mass. Processing tends to be difficult, and if it is 100 parts by mass or less, difficult processing is possible. Conversely, if the amount of the carbon nanofibers in the first composite elastomer is small, for example, less than 16.7% by mass, carbon nanofibers that do not become small cell assemblies or tie structures are relatively Many are thought to exist. Such carbon nanofibers are considered to tend to be defective portions in improving physical strength and chemical strength. Therefore, by using the first composite elastomer in which 60 parts by mass or more of carbon nanofibers are blended with respect to 100 parts by mass of the first elastomer, a carbon fiber composite material having few such defective portions can be obtained. A carbon fiber composite material in which such defective portions are reduced around 80 parts by mass can be obtained.

  The first composite elastomer thus obtained can be used as a master batch for producing a carbon fiber composite material, and the amount of carbon nanofibers in the carbon fiber composite material can be easily adjusted. Can do. In particular, since the first composite elastomer has a highly complete cell structure, a carbon fiber composite material having relatively high physical strength and chemical strength can be produced.

The first composite elastomer has a first spin-spin relaxation time (T2n) of 100 to 3000 μsec in a non-crosslinked body measured at 150 ° C. by the Hahn echo method using pulsed NMR and at ¹ H of the observation nucleus. And the component fraction (fnn) of the component having the second spin-spin relaxation time can be 0 to 0.2, in particular, the component fraction of the component having the second spin-spin relaxation time. (Fnn) can be zero. T2n and fnn measured at 150 ° C. of the first composite elastomer can represent that the carbon nanofibers are uniformly dispersed in the first elastomer as a matrix. In other words, the fact that the carbon nanofibers are uniformly dispersed in the first elastomer can be said to be in a state where the molecules of the first elastomer are constrained by the carbon nanofibers. In this state, the mobility of the molecules of the first elastomer constrained by the carbon nanofibers is smaller than that when not constrained by the carbon nanofibers. Therefore, the first spin-spin relaxation time (T2n), the second spin-spin relaxation time (T2nn), and the spin-lattice relaxation time (T1) of the first composite elastomer are the first values that do not include carbon nanofibers. It becomes shorter than the case of the elastomer alone, and in particular, it becomes shorter when the carbon nanofibers are uniformly dispersed. Moreover, in the state where the molecules of the first elastomer are constrained by the carbon nanofibers, the non-network component (non-network chain component) is considered to decrease for the following reason. That is, when the molecular mobility of the first elastomer is reduced overall by the carbon nanofibers, the portion where the non-network component cannot easily move increases, and it becomes easier to behave in the same manner as the network component. Since the network component (terminal chain) is easy to move, the non-network component is considered to decrease due to the fact that the network component (terminal chain) is easily adsorbed to the active site of the carbon nanofiber. Therefore, since the component fraction (fnn) of the component having the second spin-spin relaxation time (T2nn) is fn + fnn = 1, the component fraction is smaller than that of the first elastomer alone that does not include carbon nanofibers, and fnn It is considered that the cell structure approaches the completed body when becomes 0. Therefore, it can be seen that the first composite elastomer shows that the carbon nanofibers are uniformly dispersed when the measurement value obtained by the Hahn echo method using the pulse method NMR is in the above range, and the cell structure is completed. The degree can be estimated.

  The first elastomer used in step (a) has an unsaturated bond or group having affinity for the radical at the terminal of the carbon nanofiber in at least one of the main chain, the side chain, and the terminal chain, or Such a radical or group can be easily generated. Such unsaturated bonds or groups include double bonds, triple bonds, carbonyl groups, carboxyl groups, hydroxyl groups, amino groups, nitrile groups, ketone groups, amide groups, epoxy groups, ester groups, vinyl groups, halogen groups, urethane groups. , At least one selected from functional groups such as a burette group, an allophanate group and a urea group. The second elastomer may be the same elastomer as the first elastomer or may be a different elastomer.

  Since carbon nanofibers have a closed structure with a 5-membered ring introduced at the tip, it is easy to generate radicals and functional groups. By having an unsaturated bond or group having high affinity (reactivity or polarity) with the radical of carbon nanofiber in at least one of the main chain, side chain and terminal chain of the molecule of the first elastomer, the first elastomer Can be bonded to carbon nanofibers. This makes it possible to easily disperse the carbon nanofibers by overcoming the cohesive force. When the first elastomer and the carbon nanofibers are kneaded, the free radicals generated by cutting the molecular chain of the first elastomer attack the defects of the carbon nanofibers, and the surface of the carbon nanofibers. It can be assumed that a radical is generated.

  Examples of the first elastomer and the second elastomer include natural rubber (NR), epoxidized natural rubber (ENR), styrene-butadiene rubber (SBR), nitrile rubber (NBR), chloroprene rubber (CR), ethylene propylene rubber ( EPR, EPDM), butyl rubber (IIR), chlorobutyl rubber (CIIR), acrylic rubber (ACM), silicone rubber (Q), fluorine rubber (FKM), butadiene rubber (BR), epoxidized butadiene rubber (EBR), epichlorohydrin rubber Elastomers such as (CO, CEO), urethane rubber (U), polysulfide rubber (T); olefin (TPO), polyvinyl chloride (TPVC), polyester (TPEE), polyurethane (TPU), polyamide (TPEA), styrene (SBS Thermoplastic elastomers such as; can be used, and mixtures thereof. The first elastomer and the second elastomer may be either a rubber-based elastomer or a thermoplastic elastomer. In the case of a rubber-based elastomer, the elastomer is preferably an uncrosslinked product.

  The carbon nanofibers 80 can have an average diameter of 0.5 nm to 500 nm, an average diameter of 4 nm to 250 nm, and particularly an average diameter of 9 nm to 100 nm. Although it greatly depends on the blending amount of the carbon nanofibers, it is considered that the size of the voids in the three-dimensional network structure can be controlled by changing the average diameter of the carbon nanofibers. That is, when the average diameter of the carbon nanofiber is increased, the gap is increased, and when the average diameter of the carbon nanofiber is decreased, the gap is decreased. When the average diameter of the carbon nanofiber is 0.5 nm or more and 500 nm or less, it can be obtained on the market and can be processed in this embodiment. The average diameter of the carbon nanofiber is the outer diameter of the fiber. The carbon nanofibers can be straight fibers or curved fibers. The average diameter of the carbon nanofibers is obtained by, for example, measuring 200 or more diameters from an image taken with an electron microscope at a magnification of 5,000 (the magnification can be appropriately changed depending on the size of the carbon nanofibers), and calculating the arithmetic average value be able to.

  Examples of carbon nanofibers include so-called carbon nanotubes. Carbon nanotubes are single-walled carbon nanotubes (single wall carbon nanotubes: SWNT) in which one surface of graphite having a carbon hexagonal mesh surface is wound in one layer, and double-walled carbon nanotubes (double wall carbon nanotubes: DWNT) in two layers. Multi-walled carbon nanotubes (MWNT: multiwall carbon nanotubes) wound in three or more layers are used as appropriate. A carbon material partially having a carbon nanotube structure can also be used. In addition to the name of carbon nanotube, it may be referred to as a name such as graphite fibril nanotube or vapor grown carbon fiber.

  Single-walled carbon nanotubes or multi-walled carbon nanotubes are manufactured to a desired size by an arc discharge method, a laser ablation method, a vapor phase growth method, or the like. The carbon nanofibers may be improved in adhesion and wettability with the elastomer by performing surface treatment in advance, for example, ion implantation treatment, sputter etching treatment, plasma treatment, etc. before being kneaded with the elastomer. it can.

  Step (b) is a step of obtaining a second composite elastomer by mixing carbon black with the second elastomer. A process (b) can be performed using the open roll 2 as shown, for example in FIGS. About the open roll 2, since it is the same as FIGS. 1-3, the description is abbreviate | omitted using the same code | symbol.

  As shown in FIG. 4, the second elastomer 40 wound around the first roll 10 is masticated, and then the second elastomer wound around the first roll 10 as shown in FIG. Carbon black 90 is charged into 40 banks 44 and kneaded to obtain the second mixture 46. The mixing in the step (b) is not limited to the open roll method, and for example, a closed kneading method or a multi-screw extrusion kneading method can be used. Further, the second mixture 46 is put into the open roll 2 shown in FIG. 6 and subjected to thinning once to plural times to obtain the second composite elastomer 60 in the same manner as described in FIG. it can. Since the thinning condition is also as described with reference to FIG. 3, the description thereof is omitted here. Like the carbon nanofiber, the second composite elastomer 60 obtained in the step (b) can uniformly disperse the carbon black as a whole, and disperses the carbon black more evenly by being thinned. be able to.

  The second composite elastomer 60 thus obtained can be used as a master batch for mixing carbon black and the second elastomer into the first composite elastomer in the step (c). Therefore, by adjusting the blending amount of the second composite elastomer in the carbon fiber composite material, it is possible to match the required performance of the carbon fiber composite material without adjusting the blending amount of the first composite elastomer that is relatively difficult to process. Can be manufactured.

  As the carbon black, various grades of carbon black using various raw materials can be used. For example, as the carbon black, reinforcing carbon black such as SAF, ISAF, HAF, SRF, T, GPF, FT, and MT can be used. Carbon black, for example, can have an arithmetic average particle size of basic constituent particles of 1 nm to 10 μm, further 10 nm to 500 nm, and particularly 20 nm to 100 nm. If the average particle size of the carbon black is 1 nm or more and 10 μm or less, a reinforcing effect can be obtained. Although the compounding quantity of carbon black is not specifically limited, For example, carbon black can be 5 mass parts or more and 100 mass parts or less with respect to 100 mass parts of 2nd elastomers, Furthermore, 10 mass parts-80 mass parts In particular 20 to 60 parts by weight. If the blending amount of carbon black is 5 parts by mass or more, a reinforcing effect can be obtained, and if it is 100 parts by mass or less, it can be produced without greatly reducing workability.

  As the second elastomer, the elastomer exemplified for the first elastomer can be used. The second elastomer may be the same elastomer as the first elastomer or may be a different elastomer. The first elastomer and the second elastomer can be the same polar elastomer, for example, natural rubber. Since the first elastomer and the second elastomer have the same polarity, the first elastomer and the second elastomer are uniformly mixed throughout, and the effect of reinforcing the cell structure by the carbon nanofibers is the entire carbon fiber composite material. Can get to.

  Step (c) is a step of obtaining a carbon fiber composite material by mixing the first composite elastomer and the second composite elastomer. Step (c) can be performed, for example, using an open roll 2 as shown in FIGS. About the open roll 2, since it is the same as FIGS. 1-3, the description is abbreviate | omitted using the same code | symbol.

  As shown in FIG. 7, the second composite elastomer 60 is put into the bank 54 of the first composite elastomer 50 wound around the first roll 10 and kneaded to obtain the third mixture 56. . The mixing in the step (b) is not limited to the open roll method, and for example, a closed kneading method or a multi-screw extrusion kneading method can be used. Further, similarly to the method described with reference to FIG. 3, the third mixture is put into the open roll 2 shown in FIG. 8 and thinning is performed once to a plurality of times to obtain the carbon fiber composite material 70. Since the thinning condition is also as described with reference to FIG. 3, the description thereof is omitted here. The carbon fiber composite material 70 obtained in the step (c) can uniformly disperse carbon nanofibers and carbon black throughout.

  It is considered that the carbon fiber composite material 70 obtained in this way can add the second composite elastomer reinforced with carbon black without substantially destroying the cell structure in the first composite elastomer. Therefore, the carbon fiber composite material can effectively obtain reinforcement by the carbon nanofibers even if the amount of carbon nanofibers used is small. In particular, when the first composite elastomer is blended in an amount of 60 parts by mass or more of carbon nanofibers with respect to 100 parts by mass of the first elastomer, the cell structure has a high degree of completion with few defects in the first composite elastomer. Can be used to produce a carbon fiber composite material having relatively high physical strength and chemical strength. In particular, by thinly passing in the step (c), the second elastomer and the carbon black in the second composite elastomer can be dispersed more uniformly with respect to the first composite elastomer. The reinforcing effect by the cell structure and the tie structure in the material can be effectively obtained.

The carbon fiber composite material has a first spin-spin relaxation time (T2n) of 100 to 3000 μsec in a non-crosslinked body, measured at 150 ° C. by the Hahn echo method using pulsed NMR, and the observation nucleus is ¹ H. In addition, the component fraction (fnn) of the component having the second spin-spin relaxation time can be 0 to 0.2. The carbon fiber composite material has a first spin-spin relaxation time (T2n) longer than that of the first composite elastomer, and a component fraction (fnn) of the component having the second spin-spin relaxation time (T2nn). Is greater than that of the first composite elastomer.

  The carbon fiber composite material according to one embodiment of the present invention is obtained by the method for producing a carbon fiber composite material. The carbon fiber composite material can be crosslinked by a known method. The crosslinked carbon fiber composite material thus obtained can improve tensile strength, elongation at break and shear fatigue life. In particular, when compared at the same hardness, the carbon obtained by mixing the first composite elastomer and the second composite elastomer as compared with the carbon fiber composite material in which carbon black is mixed before the carbon nanofibers. The fiber composite material can improve tensile strength, elongation at break and shear fatigue life. The shear fatigue life can be measured by the number of times the test piece of the carbon fiber composite material is broken by repeatedly applying a shear stress.

  In the method for producing a carbon fiber composite material described here, a compounding agent usually used for processing an elastomer can be added. A well-known thing can be used as a compounding agent. Examples of the compounding agent include a crosslinking agent, a vulcanizing agent, a vulcanization accelerator, a vulcanization retarder, a softening agent, a plasticizer, a curing agent, a reinforcing agent, a filler, an anti-aging agent, a colorant, and an acid acceptor. Can be mentioned. These compounding agents can be added to the elastomer at an appropriate time during the mixing process.

  An oil field apparatus (Oilfield Apparatus) according to an embodiment of the present invention will be described. The carbon fiber composite material can be used in an oil field device. As an oil field device, for example, it can be used for a logging tool or the like. A typical embodiment of the oil field apparatus will be described below.

  For example, the logging equipment is used for physical properties such as formations and oil reservoirs in and around excavated boreholes, geometric properties of wells or casings (bore diameter, orientation, slope, etc.), flow of oil reservoirs, etc. Is a device for recording the behavior of each at every depth, and can be used, for example, in an oil field. Examples of the logging tool for oil field use include the underground use shown in FIG. 7 and the subsea use shown in FIG. The logging equipment includes wireline logging (muline logging) and mud logging (mud logging), etc., and the logging equipment (LWD: Logging Will Drilling) in which the measurement equipment is equipped in the drilling formation For example, there is a measurement while drilling (MWD). Since these logging devices work at a deep location in the ground, the surrounding environment becomes harsh for carbon fiber composite materials used for sealing materials and the like, and for example, high tensile strength and elongation at break are required. In addition, a long shear fatigue life may be required.

  FIG. 7 is a cross-sectional view schematically illustrating an underground logging tool according to one embodiment. FIG. 8 is a cross-sectional view schematically showing a logging tool for seabed use according to an embodiment.

  As shown in FIG. 7, the exploration of the underground resources on the ground surface 155 by the measuring device equipped in the excavation formation is performed from, for example, the platform and derrick formation 151 disposed above the borehole 156, and the derrick formation 151. For example, a bottom hole assembly (BHA) 160 is provided as a well logging device arranged in a well 156 formed of vertical holes and horizontal holes provided in the basement. The derrick organization 151 can include, for example, a hook 151a, a rotary swivel 151b, a kelly 151c, and a rotary table 151d. The bottom hole equipment formation 160 is fixed to the tip of a long drill string 153 extending from the derrick formation 151, for example. Inside the drill string 153, muddy water is fed from a pump (not shown) via the rotary swivel 151b, and the fluid drive motor of the bottom hole equipment organization 160 can be driven. The bottom hole equipment organization 160 includes a plurality of modules. For example, in order from the tip, a drill bit 162, a rotary steerable system (RSS) 164, a mud motor 166, a simultaneous drilling measurement module 168, And a simultaneous excavation logging module 170 can be provided. The drill bit 162 can advance excavation by rotation at the bottom portion 156 a of the well 156. A bottom hole assembly (BHA) 160 is made to enter the well 156, the underground geological structure and the like are searched, and the presence of, for example, petroleum as a target material is searched.

  In the excavation simultaneous measurement module 168, an unillustrated simultaneous excavation measurement instrument is arranged in a chamber provided in a wall portion of a pipe having a thick wall called a drill collar. The simultaneous excavation measuring instrument includes a battery, a capacitor, and various sensors that are selected according to the purpose of exploration. For example, it measures bottom hole data such as azimuth, inclination, bit direction, load, torque, temperature, and pressure. These measurement data can be transmitted to the ground in real time.

  In the excavation simultaneous logging module 170, an excavation simultaneous logging device (not shown) is disposed in a chamber provided in a wall portion of a pipe having a thick wall called a drill collar. Simultaneous drilling logging equipment includes batteries, capacitors, and various sensors that are selected for the purpose of exploration, and measures physical resistance data by measuring, for example, resistivity, porosity, sonic velocity, and gamma rays. This physical logging data can be transmitted to the ground in real time.

  The carbon fiber composite material can be used for, for example, a dynamic seal member, a static seal member, a mud motor 166, a packer, a vibration isolating / heat radiating member, etc. in the bottom hole equipment organization 160.

  In addition, the bottom hole equipment organization 160 demonstrates the example which has the drill bit 162, the rotation operation system 164, the mud motor 166, the excavation simultaneous measurement module 168, and the excavation simultaneous logging module 170 as one Embodiment. However, it is not limited to this, and can be selected and combined according to the logging application.

  As shown in FIG. 8, the exploration of underground resources using wireline logging in the ocean, for example, in a well 156 composed of vertical holes or horizontal holes provided in the seabed 154 from the platform 150 floating in the sea 152. For example, a downhole apparatus 160 ′ is entered as a logging apparatus, and the underground geological structure and the like are explored, and the presence or absence of, for example, petroleum as a target substance is explored. The downhole device 160 ′ is fixed to, for example, the end of a long cable or communication link extending from the platform, and has a housing such as a plurality of pressure vessels (not shown) inside. Inside the case, for example, electrical logging (SP logging, normal logging, induction logging, ratello logging, micro resistivity logging, etc.), radioactivity logging (gamma ray logging, neutron logging, density) Logging, nuclear magnetic resonance logging, etc.), acoustic logging (elastic wave logging, array acoustic logging, cement bond logging, etc.), geological information logging (dip meter, FMI, etc.), underground seismic survey (check) Shot velocity logging, VSP, etc.), sampling logging (sidewall / coring logging, fluid analysis logging, RFT, MDT, etc.), auxiliary logging (caliper measurement), well geometry logging , Temperature logging, etc.), special purpose logging (Logs in hostile environment), drilling pipe logging (measurement through drill drill pi) e), etc.) can be selected and enclosed in accordance with the purpose of the exploration, and the geological structure in the underground can be explored. The interior is exposed to high temperatures and is subject to vibration and impact when entering the well 156.

  The carbon fiber composite material can be used for, for example, a dynamic seal member, a static seal member, a packer, a vibration isolating / heat radiating member, etc. in the downhole device 160 '.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art can easily understand that many modifications can be made without departing from the novel matters and effects of the present invention. . Accordingly, all such modifications are intended to be included in the scope of the present invention.

(1) Sample creation step (a) of Examples 1-2:
A 6-inch open roll (roll temperature: 10 to 30 ° C., roll interval: 1.0 mm or less) is charged with 100 parts by weight (phr) of natural rubber having a weight average molecular weight of about 3 million and wound around the roll. After masticating for a minute, 80 parts by mass (phr) of carbon nanofibers (shown as “CNT” in Table 1) were added, and the first mixture was removed from the open roll. Then, the roll interval was narrowed to 0.1 mm or less, the first mixture was again put into the open roll, and thinning was repeated 5 times. At this time, the surface speed ratio of the two rolls was set to 1.1. Further, the first composite elastomer (shown as “MB1” in Table 1) obtained by setting the roll gap to 1.1 mm and passing through was fed and dispensed. The carbon nanofibers of Examples and Comparative Examples had an average diameter of 15 nm.

The uncrosslinked first composite elastomer (MB1) was measured by the Hahn echo method using pulse NMR. This measurement was performed using “JMN-MU25” manufactured by JEOL Ltd. The measurement was performed under the conditions of the observation nucleus of ¹ H, the resonant frequency of 25 MHz, and the 90 ° pulse width of 2 μsec. The decay curve was measured. Further, the sample was measured by inserting it into a sample tube up to an appropriate range of the magnetic field. The measurement temperature was 150 ° C. The measurement results are shown in Table 1 as NMR measurement values. There was no second spin-spin relaxation time (T2nn) of the first composite elastomer (MB1), and the component fraction (fnn) of the second spin-spin relaxation time was zero.

Step (b):
A 6-inch open roll (roll temperature: 10 to 30 ° C., roll interval: 1.0 mm or less) is charged with 300 mass parts (phr) of natural rubber having a weight average molecular weight of about 3 million and wound around the roll. After masticating for a minute, carbon black (shown as “CB” in Table 2) of parts by mass (phr) shown in Table 2 was added, and the second mixture was removed from the open roll. Then, the roll interval was narrowed to 0.1 mm or less, the second mixture was again put into the open roll, and thinning was repeated 5 times. At this time, the surface speed ratio of the two rolls was set to 1.1. Further, the second composite elastomer (shown as MB2 and MB3 in Table 2) obtained by setting the roll gap to 1.1 mm and passing through was fed and dispensed. The carbon black was a HAF grade having an arithmetic average particle size of 28 nm and a nitrogen adsorption specific surface area of 79 m ² / g.

Step (c):
The dispensed first composite elastomer (MB1) is again put into a 6-inch open roll (roll temperature: 10 to 30 ° C., roll interval: 1.0 mm or less), wound around the roll, and blended as shown in Table 2. A predetermined amount of the obtained second composite elastomer (MB2 in Example 1, MB3 in Example 2) was charged, and the third mixture was taken out from the open roll. The blending at this time was as shown in Table 3, assuming that the blending amount of the natural rubber combined with the first and second composite elastomers was 100 parts by mass (phr). And the roll space | interval was narrowed to 0.1 mm or less, the 3rd mixture was thrown into the open roll, and thinning was repeated 5 times. At this time, the surface speed ratio of the two rolls was set to 1.1. Furthermore, the carbon fiber composite material obtained by setting the roll gap to 1.1 mm and passing through was put and dispensed.

Further, the carbon fiber composite material was mixed with a predetermined amount of a crosslinking agent, dispensed, set in a mold, and press-crosslinked at 165 ° C. and 100 kgf / cm ^{2 for} 20 minutes, so that the carbon fibers of Examples 1 and 2 were used. A sample of composite material was obtained.

(2) Production of Samples of Comparative Examples 1 to 3 Natural rubber having a weight average molecular weight of about 3 million in 100 parts by mass (phr) on a 6-inch open roll (roll temperature: 10 to 30 ° C., roll interval: 1.0 mm or less) Is wound around a roll, masticated for 5 minutes, mixed with mass parts (phr) of carbon black shown in Table 4 and mixed with carbon nanofibers of mass parts (phr) shown in Table 4. And the mixture was removed from the open roll. And the roll space | interval was narrowed to 0.1 mm or less, this mixture was again thrown into the open roll, and thinning was repeated 5 times. At this time, the surface speed ratio of the two rolls was set to 1.1. Furthermore, the carbon fiber composite material obtained by setting the roll gap to 1.1 mm and passing through was put and dispensed.

Further, the carbon fiber composite material was mixed with a predetermined amount of a crosslinking agent, dispensed, set in a mold, and subjected to press crosslinking at 165 ° C. and 100 kgf / cm ^{2 for} 20 minutes to compare the carbons of Comparative Examples 1 to 3. A sample of fiber composite material was obtained.

(3) Measurement using pulsed NMR For the samples of carbon fiber composite materials of Examples 1 to 2 and Comparative Examples 1 to 3 of the non-crosslinked body in which no crosslinking agent is blended, the Hahn-echo method using pulsed NMR Measurement was carried out. This measurement was performed using “JMN-MU25” manufactured by JEOL Ltd. The measurement was performed under the conditions of the observation nucleus of ¹ H, the resonant frequency of 25 MHz, and the 90 ° pulse width of 2 μsec. The decay curve was measured. Further, the sample was measured by inserting it into a sample tube up to an appropriate range of the magnetic field. The measurement temperature was 150 ° C. The measurement results are shown in Tables 3 and 4 as NMR measurement values.

(4) Measurement of normal physical properties As the normal physical properties, hardness, tensile strength, elongation at break, 50% and 100% at room temperature for samples of the crosslinked carbon fiber composite materials of Examples 1-2 and Comparative Examples 1-3. The modulus was measured. The measurement results are shown in Tables 3-4. The measurement results are shown in FIG. 11 to FIG. 12 (hardness for the examples, and ▲ for the comparative examples) between hardness and tensile strength, or the relationship between hardness and elongation at break.
Rubber hardness (shown as "Hs (JIS-A)" in Tables 3 to 4) was measured based on JIS K 6253.
Tensile strength (shown as “TS (MPa)” in Tables 3 to 4), elongation at break (shown as “EB (%)” in Tables 3 to 4), stress at 50% elongation (Table 3) -4 and "σ50 (MPa)"), and stress at 100% elongation (shown as "σ100 (MPa)" in Tables 3 to 4) were cut into a JIS No. 6 dumbbell shape. The test piece was measured by performing a tensile test based on JIS K6251 using a tensile tester manufactured by Shimadzu Corporation at 23 ± 2 ° C. and a tensile speed of 500 mm / min. “Σ50” and “σ100” may be referred to as “50% modulus (M50)” and “100% modulus (M100)”.

  According to Tables 3-4 and FIGS. 11-12, when Examples 1-2 and Comparative Examples 1-3 were compared, if the hardness was approximately the same, Examples 1 and 2 were compared with Comparative Examples 1-3. Values of tensile strength and elongation at break were larger. In particular, Example 1 and Comparative Example 3 were the same in composition but different in mixing method. However, if the hardness was almost the same, the values of tensile strength and elongation at break were larger in Example 1. .

(5) Shear Test Samples of the crosslinked carbon fiber composite materials of Examples 1-2 and Comparative Examples 1-3 were cut into prismatic test pieces (5 mm × 5 mm × thickness 1 mm), and the two test pieces were double sandwiched. The test force (4MPa) was fixed by the method, the test force (4MPa) was kept constant, the shear test was conducted with reference to the JIS-K6394 forced vibration non-resonance method at a frequency of 3Hz and room temperature, and the number of times the test piece was broken was measured. . The measurement results are shown in Tables 5 and 6 as “fatigue frequency”. In addition, the measurement results are shown in FIG. 13 as a graph of the relationship between the hardness and the number of fatigues (Example: ●, Comparative Example: ▲).

  According to Tables 5 and 6 and FIG. 13, when Examples 1-2 and Comparative Examples 1-3 were compared, if the hardness was approximately the same, Examples 1-2 were more than Comparative Examples 1-3. There was a lot of fatigue. In particular, Example 1 and Comparative Example 3 had the same blending amount and differed only in the mixing method. However, even though the hardness was almost the same, Example 1 had a greater number of fatigues.

  2 Open roll, 10 1st roll, 20 2nd roll, 30 1st elastomer, 34 bank, 36 1st mixture, 40 2nd elastomer, 44 bank, 46 2nd mixture, 50 1st roll Composite elastomer, 54 banks, 56 third mixture, 60 second composite elastomer, 70 carbon fiber composite material, 80 carbon nanofiber, 90 carbon black, V1, V2 rotational speed, 150 platform, 151 derrick knitting, 151a hook, 151b rotary swivel, 151c kelly, 151d rotary table, 152 sea, 153 drill string, 154 sea bottom, 155 surface, 156 well, 156a bottom, 160 well bottom organization, 160 'downhole device, 162 drill bit, 164 Rotation System, 166 mud motor, 168 simultaneous drilling measurement module, 170 simultaneous drilling logging module

Claims (7)

(A) a step of obtaining a first composite elastomer by mixing carbon nanofibers with the first elastomer and then performing thinning at 0 ° C. to 50 ° C. using an open roll having a roll interval of 0.5 mm or less; ,
A step (b) of obtaining a second composite elastomer by mixing carbon black with the second elastomer;
A step (c) of obtaining a carbon fiber composite material by mixing the first composite elastomer and the second composite elastomer;
A method for producing a carbon fiber composite material, comprising: In claim 1,
The step (a) is a method for producing a carbon fiber composite material in which 60 parts by mass or more and 100 parts by mass or less of carbon nanofibers are blended with respect to 100 parts by mass of the first elastomer. In claim 1 or 2,
The first composite elastomer has a first spin-spin relaxation time (T2n) of 100 to 3000 μsec in an uncrosslinked body, as measured at 150 ° C. by a Hahn echo method using pulsed NMR, The spin-spin relaxation time (T2nn) does not exist in the method for producing a carbon fiber composite material. In any one of Claims 1 thru | or 3,
The step (b) is a method for producing a carbon fiber composite material in which 20 parts by mass or more and 150 parts by mass or less of carbon black are blended with respect to 100 parts by mass of the second elastomer. In any one of Claims 1 thru | or 4,
The method for producing a carbon fiber composite material, wherein the first elastomer and the second elastomer are natural rubber.   A carbon fiber composite material obtained by the method for producing a carbon fiber composite material according to any one of claims 1 to 5.   An oil field device using the carbon fiber composite material according to claim 6.

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