JP2015071759A - Production method of carbon nanotube-including polyurethane composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of carbon nanotube-including polyurethane composite and a composite, in which the polyurethane composite on which carbon nanotubes are dispersed in a uniform state can be produced with a simple method, and the composite can exhibit improved conductivity and mechanical physical properties.SOLUTION: The production method of carbon nanotube-including polyurethane composite of the embodiment comprises: a step for preparing dispersion fluid in which a polyol and a self-aligned carbon nanotube are mixed; and a step for adding a diisocyanate compound to the dispersion fluid for polymerization reaction under the presence of a chain extender.

Description

  The present invention relates to a method for producing a carbon nanotube-containing polyurethane composite.

  Polyurethane is a polymer that is applied to various industrial fields such as automobile field, electronic material field, clothing field, and paint field, and many physical properties such as tensile strength, wear degree, and elongation rate are adjusted according to the application field. Is required.

  Generally, the physical properties of polymers are adjusted by changing the mixing ratio of raw materials or mixing functional additives. Recently, carbon-based materials such as carbon black, carbon nanotubes, and graphene are used as polymers. Attempts have been made to control the physical properties of polymers by combining them.

  Among the carbon-based materials, carbon nanotubes are typical carbon nanostructures, which are excellent in thermal conductivity, electrical conductivity, mechanical strength, etc., and can be applied to various electrical devices and high-strength nanocomposites. Has attracted attention as a new material.

  However, since carbon nanotubes are entangled by a strong van der Waals force, there is a problem that they are not uniformly dispersed in the polymer medium to be combined. For this purpose, attempts have been made to introduce a functional group on the surface of the carbon nanotube for modification, or to apply a multi-step physical process. However, such a method requires a complicated pretreatment process, which leads to a decrease in productivity, and not only an organic solvent harmful to the human body or the environment is used. There are many problems such as deterioration of physical properties due to damage.

  The present invention is to provide a method capable of producing a polyurethane composite in which carbon nanotubes are uniformly dispersed by a simpler method.

  The present invention also provides a carbon nanotube-polyurethane composite produced by the above method and having improved electrical conductivity and mechanical properties.

  According to the present invention, preparing a dispersion in which a polyol and a self-aligned carbon nanotube are mixed, and in the presence of a chain extender, a diisocyanate compound is added to the dispersion. And a method for producing a carbon nanotube-polyurethane composite comprising the steps of adding and polymerizing.

  The present invention also provides a method for producing a carbon nanotube-polyurethane composite comprising a step of polymerizing a dispersion containing a polyol, a self-aligning carbon nanotube and a diisocyanate compound in the presence of a chain extender.

  According to one embodiment, the dispersion comprises a composition comprising a polyol and self-aligning carbon nanotubes, or a composition comprising a polyol, self-aligning carbon nanotubes and a diisocyanate compound for 30-300 under a bead mill. Can be prepared by mixing for minutes.

  And according to one embodiment, 0.5 to 5 parts by weight of self-aligned carbon nanotubes, 1 to 10 parts by weight of chain extender, and 5 to 30 parts by weight of diisocyanate with respect to 100 parts by weight of the polyol. Compounds can be used.

  Further, according to an embodiment, the self-aligned carbon nanotube may include a plurality of carbon nanotubes having a diameter of 5 to 20 nm and a length of 1 to 600 μm.

  In addition, according to an embodiment, the polyol may have a weight average molecular weight of 500 to 10,000. The polyol may be one or more compounds selected from the group consisting of polytetramethylene glycol, polyethylene glycol, polypropylene glycol, and polycaprolactone diol.

  According to one embodiment, the diisocyanate compound may be 1,6-hexamethylene diisocyanate, 4,4′-methylene diphenyl diisocyanate, isophorone diisocyanate. (Isophorone diisocyanate), 4,4'-diisocyanatodicyclohexylmethane (4,4'-diisocyanato dicyclohexylmethane), tetramethylene diisocyanate, methylpentamethylene diisocyanate (methylethylene diisocyanate) anate), todecamethylene diisocyanate, 1,4-diisocyanatocyclohexane, 4,4'-diisocyanatodicyclohexylpropane- (2,2) (4,4 ' -Diisocyanato dichrohexylpropane- (2,2)), 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene (2,4-diisocyanatotoluene), 2,6-di- Isocyanatotoluene (2,6-diisocyanatotoluene), diisocyanatodiphenylmethane (diisocyanatodiphenyl) 1 or more kinds selected from the group consisting of phenylmethane, tetramethylxylene diisocyanate, p-xylene diisocyanate, and p-isopropylidene diisocyanate.

  In one embodiment, the chain extender may be one or more compounds selected from the group consisting of ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol.

  Meanwhile, the carbon nanotube-polyurethane composite according to an embodiment has an electrical conductivity (S / cm) increased by 10 to 10,000 times as compared with polyurethane compounded with a networked carbon nanotube. Can have.

In addition, the carbon nanotube-polyurethane composite according to an embodiment may have a tensile strength (kgf / cm ² ) increased by 10 to 100% as compared to polyurethane combined with a network-structured carbon nanotube.

  In addition, the carbon nanotube-polyurethane composite according to an embodiment may have an elongation (%) increased by 50 to 400% as compared to polyurethane combined with a network-structured carbon nanotube.

  According to the present invention, it is possible to produce a polyurethane composite in which carbon nanotubes are uniformly dispersed by a simpler method, and the composite can exhibit improved electrical conductivity and mechanical properties. . The carbon nanotube-polyurethane composite can be usefully used in various industrial fields such as automobile field, electronic material field, clothing field, and paint field.

Self-aligned carbon nanotubes [FIG. 1 (a)] and entangled carbon nanotubes [FIG. 1 (b)] were magnified using a scanning electron microscope (SEM). It is a photograph. The surface of the carbon nanotube-polyurethane composite [FIG. 2 (a)] according to one embodiment of the present invention and the composite according to the comparative example [FIG. 2 (b)] are enlarged using a scanning electron microscope (SEM). It is an observed photograph.

  Hereinafter, a method for producing a carbon nanotube-polyurethane composite according to a specific embodiment of the present invention and a composite therewith will be described in more detail.

  Prior to that, unless expressly stated throughout the specification, the terminology is only for the purpose of referring to particular embodiments and is not intended to limit the invention. As used herein, the singular form includes plural forms unless the word clearly indicates the opposite meaning. Also, as used herein, the meaning of “comprising” embodies specific characteristics, regions, integers, steps, operations, elements and / or components, and other specific properties, regions, integers, steps, operations, It does not exclude the presence or addition of elements, components and / or groups.

  Meanwhile, in the process of researching the carbon nanotube (hereinafter referred to as “CNT”)-containing polyurethane composite, the present inventors have developed a self-aligned CNT form as a general CNT form. Compared to the above, it was confirmed that excellent dispersibility with respect to polyurethane was exhibited even without a separate pretreatment. Accordingly, when using the self-aligned CNT, the CNT-polyurethane composite having significantly improved electrical conductivity and mechanical properties can be obtained through a simplified method that does not require a separate pretreatment process for the CNT. Confirmed that it can be provided.

  According to such an embodiment of the present invention, preparing a dispersion in which a polyol and a self-aligned carbon nanotube are mixed, and in the presence of a chain extender, And a step of adding a diisocyanate compound to the dispersion to cause a polymerization reaction, and a method for producing a carbon nanotube-polyurethane composite.

  Hereinafter, each step that may be included in the manufacturing method will be described in detail.

  First, a method of manufacturing a CNT-polyurethane composite according to an embodiment may include a step of preparing a dispersion in which a polyol and a self-aligned CNT are mixed.

  The polyol is a compound having an equivalent of 2 or more hydroxy groups per molecule, and forms a urethane bond by reaction with an isocyanate compound. In the present invention, as the polyol, ordinary compounds used for forming polyurethane can be applied without any particular limitation. However, as a non-limiting example, the polyol may be one or more compounds selected from the group consisting of polytetramethylene glycol, polyethylene glycol, polypropylene glycol, and polycaprolactone diol. In order to ensure the mechanical properties required for polyurethane, the polyol has a weight average molecular weight of 500 to 10,000, or 1,000 to 5,000, or 1,000 to 4,000, or 1 , 500 to 3,500, or 2,000 to 3,500.

  On the other hand, as shown in FIG. 1, the self-aligned CNT [FIG. 1 (a)] is different from a general CNT having an entangled structure (FIG. 1 (b)). It includes a plurality of self-aligned bundles of CNTs having a diameter of ten nanometer scale and a length of several to several hundred micrometers. Accordingly, when the self-aligned CNTs are mixed with a polyol (medium), the plurality of CNTs forming a bundle can be uniformly dispersed in the polyol in a form of being unwound. However, a general CNT having an entangled structure has an agglomerate due to a decrease in dispersibility due to a strong van der Waals force between the CNTs, whereas the self-aligned CNT has a separate structure. More uniform and improved electrical, mechanical, and thermal properties with excellent dispersibility without applying pretreatment (for example, introducing functional groups on the CNT surface) or multi-step physical dispersion methods It is possible to provide a composite having specific physical properties.

  As the self-aligned CNT, a normal CNT having a shape in which a plurality of CNTs are arranged in a bundle shape may be used, and a single walled carbon nanotube or a multiwalled carbon nanotube. The structure such as) is not particularly limited. However, according to an embodiment, the self-aligned CNT includes a plurality of carbon nanotubes having a diameter of 5 to 20 nm and a length of 1 to 600 μm, which is more advantageous in realizing the physical property improving effect according to the present invention. Can be.

  Meanwhile, according to one embodiment, the dispersion of the polyol and the self-aligned CNT is mixed for 30 to 300 minutes, or 30 to 120 minutes, or 30 to 90 minutes, or 30 under a bead mill. Can be prepared through a method of mixing for ~ 60 minutes. In other words, the self-aligned CNT may be restricted in the expression of a uniform dispersion state in a general mixing process, but by applying the optimum dispersion method as in the above-described embodiment, a network-structured CNT is obtained. A dispersion having an excellent dispersibility compared to the above can be prepared.

  At this time, the self-aligned CNT is 0.5 to 5 parts by weight, or 0.5 to 3.5 parts by weight, or 1 to 3.5 parts by weight, or 1 to 3 parts by weight based on 100 parts by weight of the polyol. It can be included in parts by weight. That is, it is advantageous that the self-aligned CNT is contained in an amount of 0.5 parts by weight or more with respect to 100 parts by weight of the polyol so that the effect of improving the physical properties required in the present invention is sufficiently exhibited. However, when an excessive amount of CNTs is added, the dispersion state of CNTs becomes poor and CNT aggregates are formed in the composite, which can reduce the mechanical properties of the composite. Therefore, it is advantageous that the self-aligned CNT is contained in an amount of 5 parts by weight or less based on 100 parts by weight of the polyol.

  And if necessary, the dispersion may further contain a hydrocarbon-based diluent. The hydrocarbon-based diluent is a component for adjusting the viscosity of the composite to optimize the workability according to the application field, and is an aliphatic hydrocarbon or aromatic hydrocarbon having 6 to 10 carbon atoms, Or a mixture thereof. The hydrocarbon diluent may be included in an amount of 0.5 to 5 parts by weight with respect to 100 parts by weight of the polyol.

  On the other hand, the method for producing a CNT-polyurethane composite according to an embodiment may include a step of adding a diisocyanate compound to the dispersion and causing a polymerization reaction in the presence of a chain extender.

  According to one embodiment, the diisocyanate compound is a compound that forms a urethane bond by reaction with the polyol, and a normal compound used for forming a polyurethane can be applied without any particular limitation. However, as a non-limiting example, the diisocyanate compound may be 1,6-hexamethylene diisocyanate, 4,4′-methylene diphenyl diisocyanate, isophorone diisocyanate. (Isophorone diisocyanate), 4,4'-diisocyanatodicyclohexylmethane (4,4'-diisocyanato dicyclohexylmethane), tetramethylene diisocyanate, methylpentamethylene diisocyanate (methylethylene diisocyanate) anate), todecamethylene diisocyanate, 1,4-diisocyanatocyclohexane, 4,4'-diisocyanatodicyclohexylpropane- (2,2) (4,4 ' -Diisocyanato dichrohexylpropane- (2,2)), 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene (2,4-diisocyanatotoluene), 2,6-di- Isocyanatotoluene (2,6-diisocyanatotoluene), diisocyanatodiphenylmethane (diisocyanatodiphenyl) 1 or more kinds selected from the group consisting of phenylmethane, tetramethylxylene diisocyanate, p-xylene diisocyanate, and p-isopropylidene diisocyanate.

  At this time, the content of the diisocyanate compound is not particularly limited because it can be determined in consideration of the equivalent ratio with the polyol, the physical properties of the polyurethane to be obtained, and the like. However, according to one embodiment, the diisocyanate compound is included in 5 to 30 parts by weight, or 15 to 30 parts by weight, or 20 to 30 parts by weight, or 25 to 30 parts by weight with respect to 100 parts by weight of the polyol. It can be advantageous to ensure sufficient physical properties.

  In addition, the chain extender can be applied without any particular limitation to the usual compounds used to form polyurethane. However, as a non-limiting example, it may be one or more compounds selected from the group consisting of ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol.

  The content of the chain extender is not particularly limited because it can be determined in consideration of the physical properties of the polyurethane to be finally formed. However, according to an embodiment, the chain extender may be contained in 1 to 10 parts by weight, or 5 to 10 parts by weight with respect to 100 parts by weight of the polyol, which may be advantageous for securing sufficient physical properties. .

  In the polymerization reaction, an organic solvent such as dimethylformamide, methyl ethyl ketone, methyl isobutyl ketone, xylene, toluene, 1-methyl-2-pyrrolidone can be used. At this time, it is preferable that the organic solvent does not contain moisture. If water is contained in the organic solvent, the water and the isocyanate group react to generate carbon dioxide, thereby forming an unintended foam-form composite. According to an embodiment, the organic solvent may be included at 100 to 500 parts by weight, or 200 to 500 parts by weight, or 200 to 400 parts by weight, or 200 to 300 parts by weight with respect to 100 parts by weight of the polyol. . In other words, when the content of the organic solvent is small, sufficient viscosity may not be secured and stirring may be difficult, and when the content of the organic solvent is excessively large, the drying time may be long and process efficiency may be lowered. Therefore, it is advantageous to adjust within the above range.

  The composite obtained through the polymerization reaction may include an unreacted isocyanate group. In order to remove the unreacted isocyanate group, a post-treatment process may be further performed by adding a compound such as dibutylamine.

  Meanwhile, according to another embodiment of the present invention, a method for producing a carbon nanotube-polyurethane composite including a step of polymerizing a dispersion containing a polyol, a self-aligning carbon nanotube and a diisocyanate compound in the presence of a chain extender. Is provided.

  That is, in the method for producing a composite according to the present invention, i) as in the above-described embodiment, a dispersion in which polyol and self-aligned CNT are mixed is separately prepared, and a diisocyanate compound is added thereto to perform a polymerization reaction. Can be done in a way that And the manufacturing method of the composite_body | complex by this invention may be performed by the method of carrying out the polymerization reaction, mixing a polyol, self-alignment CNT, and a diisocyanate compound.

  Here, the dispersion liquid may be prepared by a method of mixing a composition containing a polyol, a self-aligning carbon nanotube and a diisocyanate compound in a bead mill for 30 to 300 minutes as described above.

  The description of the polyol, the self-aligned CNT, the diisocyanate compound, the chain extender and the like is replaced with the above-described content.

  Meanwhile, according to still another embodiment of the present invention, a CNT-polyurethane composite including polyurethane and CNT dispersed in the polyurethane is provided.

  The composite is a composite in which CNTs are uniformly dispersed in a matrix containing polyurethane, and is manufactured by the method described above. As described above, self-aligned CNTs are used in the composite manufacturing method, so that the composites have excellent CNT dispersibility and more uniform electrical, mechanical, and thermal properties. Can be provided.

  According to one embodiment, the CNT-polyurethane composite produced by the above-described method is about 10 to 10,000 times as compared to polyurethane compounded using the same amount of common CNTs having a network structure. Or about 50 to 10,000 times, or 70 to 10,000 times, or 70 to 9,600 times improved electrical conductivity.

And, according to one embodiment, the CNT-polyurethane composite produced by the above-described method is about 10 to 100% when compared with polyurethane compounded using the same amount of common CNT having a network structure. Or about 15-30%, or 15-25% improved tensile strength (kgf / cm < ² >).

  As a result, the CNT-polyurethane composite produced by the above-described method can exhibit excellent elongation while having improved tensile strength. That is, according to one embodiment, the CNT-polyurethane composite produced by the above-described method is approximately 50-400% when compared to polyurethane compounded using the same amount of common CNTs having a network structure. Or about 100-200%, or 100-150% improved elongation (%).

  In particular, the CNT-polyurethane composite produced by the above-described method can effectively maintain the initial excellent physical properties even after being stored in a poor environment by including CNTs with an improved degree of dispersion. Can do. According to one embodiment, when the tensile strength and the elongation are measured after storing the CNT-polyurethane composite at about 80 ° C. for 2 weeks, the tensile strength and the elongation measured in the initial measurement are 80 % Or more, or a level of 90% or more can be maintained.

  However, the physical properties of the CNT-polyurethane composite may vary depending on the structure, type, molecular weight, and the like of polyurethane as a medium. If the person has ordinary knowledge in the technical field to which the present invention belongs, the composite can be obtained through the manufacturing method. You will be able to adjust the physical properties.

  Such a CNT-polyurethane composite of the present invention can be usefully used in various industrial fields such as the automobile field, electronic material field, clothing field, and paint field.

  Hereinafter, preferred examples for understanding the present invention will be presented. However, the following examples are only for illustrating the present invention, and the present invention is not limited thereto.

Example 1
A bead mill comprising a composition comprising about 2% by weight of self-aligned CNT (manufacturer: Hanwha Chemical, product name: CM-250) and about 98% by weight of polyol (polypropylene glycol, weight average molecular weight of about 3,000). The dispersion liquid was prepared by mixing for about 60 minutes using a mill, bead 0.8Φ).

  Then, about 80 g of the dispersion, about 5 g of 1,4-butanediol, about 20 g of aliphatic diisocyanate (1,6-hexamethylene diisocyanate), and about 200 g of dimethylformamide are charged into the reactor. After stirring for about 1 hour, a carbon nanotube-polyurethane composite was obtained by reacting with drying at about 70 ° C. for about 24 hours.

Example 2
About 3% by weight of self-aligned CNT (Manufacturer: Hanwha Chemical, product name: CM-250), about 94% by weight of polyol (polypropylene glycol, weight average molecular weight of about 3,000), and about 3% by weight of carbonization A composition containing a hydrogen diluent (C6-C10 aliphatic hydrocarbon mixture) was mixed for about 60 minutes using a bead mill (bead 0.8Φ) to prepare a dispersion.

  Then, about 80 g of the dispersion, about 5 g of 1,4-butanediol, and about 20 g of aliphatic diisocyanate (1,6-hexamethylene diisocyanate) are added to the reactor and stirred at room temperature for about 1 hour. The carbon nanotube-polyurethane composite was obtained by a method of reacting while drying at about 70 ° C. for about 24 hours.

Example 3
About 78 g polyol (polypropylene glycol, weight average molecular weight about 3,000), about 5 g 1,4-butanediol, about 20 g aliphatic diisocyanate (1,6-hexamethylene diisocyanate), about 200 g dimethylformamide, and A composition containing about 2 g of self-aligned CNT (manufacturer: Hanwha Chemical, product name: CM-250) was mixed for about 60 minutes using a bead mill (bead 0.8Φ). And after stirring this at room temperature for about 1 hour, the carbon nanotube-polyurethane composite was obtained by the method of making it react for about 24 hours drying at about 70 degreeC.

Comparative Example Carbon nanotube-polyurethane was produced in the same manner as in Example 1 except that CNTs having an encapsulated structure (manufacturer: Hanwha Chemical, product name: CM-95) were used instead of the self-aligned CNTs. A complex was obtained.

Test Example 1 (Observation of dispersion state of carbon nanotube)
The surface of each composite obtained through Example 1 and Comparative Example was observed using a scanning electron microscope (SEM), and the results are shown in FIG.

  As can be seen from FIG. 2, it was confirmed that the carbon nanotubes were uniformly dispersed in the composite according to Example 1 (FIG. 2A). In comparison with this, it was confirmed that the carbon nanotubes were not uniformly dispersed in the composite according to the comparative example [(b) of FIG. 2].

Test Example 2 (Measurement of electrical conductivity and mechanical properties)
With respect to each composite obtained through the examples and comparative examples, the electrical conductivity and mechanical properties were measured by the following methods, and the results are shown in Table 1 below.

  1) Electrical conductivity (S / cm): The resistance of the composite was measured using the LORESTA equipment according to JIS-K6911 standard, and the specimen standard of the composite was measured to determine the electrical conductivity.

2) Tensile strength (kgf / cm ² ) and elongation rate (%): Ten test pieces of ASTM D638 Type I standard were prepared. After measuring the initial tensile strength and the elongation of the five specimens using the Universal Testing Machine, the average value was obtained. The remaining five specimens were stored at about 80 ° C. for 2 weeks, and then the tensile strength and elongation were measured in the same manner.

  As can be seen from Table 1, it was confirmed that the composites according to Examples 1 to 3 had an electrical conductivity increased by about 70 to 9500 times compared to the composites of Comparative Examples. In addition, it was confirmed that the composites according to Examples 1 to 3 improved the initial elongation by about 100 to 140% while exhibiting tensile strength increased by about 18% to 25% compared to the composite of Comparative Example. It was done. Thus, the composites of the examples manufactured using self-aligned CNTs have significantly improved electrical properties and mechanical properties as compared with the composites of comparative examples manufactured using network-structured CNTs. It was confirmed to have physical properties.

  The composites according to Examples 1 to 3 can maintain the level of about 94% or more when compared with the initial physical properties even after being stored in a poor environment, and the level of about 80% when compared with the initial physical properties. It was confirmed that it can be maintained for about 4 weeks or more.

Claims (13)

Preparing a dispersion in which a polyol and a self-aligned carbon nanotube are mixed;
Adding a diisocyanate compound to the dispersion in the presence of a chain extender to cause a polymerization reaction;
A method for producing a carbon nanotube-polyurethane composite comprising: Polymerizing a dispersion containing a polyol, self-aligning carbon nanotubes and a diisocyanate compound in the presence of a chain extender;
A method for producing a carbon nanotube-polyurethane composite comprising:   The dispersion is prepared by mixing a composition containing a polyol and self-aligning carbon nanotubes, or a composition containing a polyol, self-aligning carbon nanotubes and a diisocyanate compound for 30 to 300 minutes under a bead mill. The manufacturing method of the carbon nanotube-polyurethane composite of Claim 1 or 2.   The self-aligning carbon nanotube of 0.5 to 5 parts by weight, 1 to 10 parts by weight of a chain extender, and 5 to 30 parts by weight of a diisocyanate compound are used with respect to 100 parts by weight of the polyol. 2. A method for producing a carbon nanotube-polyurethane composite according to 2.   The method of manufacturing a carbon nanotube-polyurethane composite according to claim 1 or 2, wherein the self-aligned carbon nanotube includes a plurality of carbon nanotubes having a diameter of 5 to 20 nm and a length of 1 to 600 µm.   The method for producing a carbon nanotube-polyurethane composite according to claim 1 or 2, wherein the polyol has a weight average molecular weight of 500 to 10,000.   The method for producing a carbon nanotube-polyurethane composite according to claim 1 or 2, wherein the polyol is one or more compounds selected from the group consisting of polytetramethylene glycol, polyethylene glycol, polypropylene glycol, and polycaprolactone diol.   Examples of the diisocyanate compound include 1,6-hexamethylene diisocyanate, 4,4′-methylene diphenyl diisocyanate, isophorone diisocyanate, 4,4 ′. -Diisocyanatodicyclohexylmethane (4,4'-diisocyanato dicyclohexylmethane), tetramethylene diisocyanate, methylpentamethylene diisocyanate, todecamethyrene Diisocyanate, 1,4-diisocyanatocyclohexane, 4,4′-diisocyanatodicyclohexylpropane- (2,2) (4,4′-diisocyanatodicyropropylnepropyl (2) , 2)), 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene (2, 6-diisocyanatotoluene), diisocyanatodiphenylmethane 1 or more compounds selected from the group consisting of tetramethylxylene diisocyanate, p-xylene diisocyanate, and p-isopropylidene diisocyanate, Or a method for producing a carbon nanotube-polyurethane composite as described in 2.   The carbon nanotube-polyurethane composite according to claim 1 or 2, wherein the chain extender is one or more compounds selected from the group consisting of ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol. Production method.   3. The carbon nanotube according to claim 1, wherein the carbon nanotube has an electric conductivity (S / cm) increased by 10 to 10,000 times as compared with a polyurethane compounded with a networked carbon nanotube (enanted carbon nanotube). A method for producing a polyurethane composite. 3. The method for producing a carbon nanotube-polyurethane composite according to claim 1, which has a tensile strength (kgf / cm ² ) increased by 10 to 100% as compared with polyurethane compounded with a network-like carbon nanotube.   3. The method for producing a carbon nanotube-polyurethane composite according to claim 1, which has an elongation (%) increased by 50 to 400% as compared with polyurethane compounded with a network-structured carbon nanotube.   A carbon nanotube-polyurethane composite produced by the method according to claim 1 or 2.