Thermally conductive and moisture-permeable film

Abstract

To provide a thermally conductive and moisture-permeable film.SOLUTION: There is provided a thermally conductive and moisture-permeable film, wherein several layers of graphene with a solid content weight ratio of 1 to 30 wt% and a polyrotaxane with a solid content weight ratio of 0.05 to 10 wt% are added to a polyurethane resin, and in addition to having moisture permeability and waterproofness the polyurethane resin has high thermal conductivity due to the few-layer graphene and the addition of polyrotaxane improves the dispersion of several layers of graphene and the extensibility of polyurethane resin, so that the formed thermally conductive and moisture-permeable film can maintain the extensibility without increasing the film thickness. In this way, the problem of the prior art that after adding a thermally-conductive material to the polyurethane film, a certain extensibility can only be obtained by increasing the film thickness is solved, and the film extensibility can be maintained without increasing the film thickness after adding the thermally-conductive material to the polyurethane film.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a thermally conductive and moisture permeable film, and more particularly to a thermally conductive and moisture permeable film that maintains thin film extensibility without increasing film thickness. [Background technology]

[0002] The composition of polyurethane molecules has many hydrogen bonds, which strengthens the intermolecular interaction, has strong adhesive power, and has stable chemical properties, and can easily form a thin film with waterproof and moisture permeability, so it is widely used in fabric thin film attachment technology. The attachment of fabrics with waterproof and moisture permeable thin films is a standard element of outdoor mountaineering jackets and coats and other related products currently on the market, and many waterproof and moisture permeable membrane attachment fabrics emphasize their high moisture permeability and waterproofness, which protect the wearer from getting wet in heavy rain when playing outdoor sports, and the highly moisture permeable thin film allows the wearer to smoothly discharge moisture on the surface of the body, preventing the wearer from feeling hot when wearing the garment. Summary of the Invention [Problem to be solved by the invention]

[0003] When worn for a long time, a considerable amount of moisture accumulates inside and outside the fabric, greatly reducing the moisture permeability of the thin film. When the accumulated heat is absorbed by the body surface through moisture, it cannot be effectively transferred and diffused due to the low thermal conductivity of polyurethane itself, causing the human body to feel stuffy and uncomfortable when worn. Therefore, in order to improve the thermal conductivity of polyurethane itself without affecting the moisture permeability and waterproofness, an inventor has bonded a thermal conductive additive to the polyurethane thin film to improve the heat dissipation and greatly improve the wearing experience of consumers. However, in the above-mentioned conventional technology, after the thermal conductive additive is bonded to the polyurethane thin film, the interface between the thermal conductive additive and the polyurethane is not compatible, and the flexibility of the polyurethane thin film is reduced, and finally, the thickness is increased to maintain the extensibility of the thin film, and then it can only be attached to the surface of the fabric.

[0004] Therefore, the inventors believed that the above-mentioned drawbacks could be improved, and as a result of extensive research, they came to propose the present invention, which rationally and effectively improves the problems.

[0005] The objective of the present invention is to solve the problem in the prior art that after adding a thermally conductive material to a polyurethane thin film, the strength of the thin film is reduced due to the incompatibility of the interface between the thermally conductive additive and the polyurethane base material, and the thickness of the thin film must be increased in order to obtain extensibility, and to maintain the extensibility of the thin film without increasing the thickness after adding a thermally conductive material to the polyurethane thin film.

[0006] Another object of the present invention is to improve the thermal conductivity and visible light blocking rate of the thin film by improving the dispersion and alignment of the thermally conductive material. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention employs the following means. A thermally conductive and moisture-permeable film according to one embodiment of the present invention is obtained by adding several-layer graphene having a solid content weight ratio of 1 to 30 wt% and polyrotaxane having a solid content weight ratio of 0.05 to 10 wt% to a polyurethane resin, so that the polyurethane resin has moisture permeability and waterproofness, and the several-layer graphene is added to increase thermal conductivity. The addition of polyrotaxane improves the dispersibility of several-layer graphene in the polyurethane resin by utilizing the affinity of the linear polymer, terminal group, and graphene base surface in the molecular structure, and strengthens the alignment of graphene. At the same time, a crosslinking reaction is generated between the reactive functional group of the cyclic molecule in the polyrotaxane molecular structure and the reactive functional group of the polyurethane resin and the crosslinking agent, generating a movable crosslinking point in the material, improving the extensibility and flexibility of the polyurethane resin (substrate), and the formed thermally conductive and moisture-permeable film maintains extensibility without increasing the film thickness. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is an explanatory diagram showing the preparatory molding of a thermally conductive and moisture permeable film according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a thermally conductive and moisture permeable film according to an embodiment of the present invention will be described.

[0010] First, the thermally conductive and moisture permeable film according to the present invention will be described in more detail with reference to Fig. 1. That is, one embodiment of the present invention includes the following configuration.

[0011] a. few-layer graphene having a solid content of 1-30 wt%, at least 95% of which has a lateral size of 6000 nm-8000 nm and a thickness of 2-3 nm, a width-to-thickness ratio in the range of 200-400, and an oxygen content of at least less than 0.1%, a surfactant, and a solvent are prepared into a high-concentration few-layer graphene dispersion paste having a liquid viscosity in the range of 1000-3000 cps, and after high-speed grinding, shearing, and dispersion, the few-layer graphene is reduced to a lateral size of 100 nm-1500 nm and a thickness of 1.5-2.5 nm, and the concentration distribution difference of the paste is less than 5%. b. A polyrotaxane having a solid content of 0.05-10 wt% and a silicon dioxide powder (anti-adhesive agent) having a solid content of 0.1-5 wt% are added in portions to the high-concentration few-layer graphene dispersion paste in a fluid state, and mixed uniformly by shear mixing to form a few-layer graphene composite fluid having a viscosity in the range of 5000-10000 cps and a particle size distribution D90 of the paste of less than 15 μm. Polyrotaxane refers to a compound containing a linear polymer and a cyclic molecule, and the linear polymer is the axial molecule of the compound, has a molecular weight of 10,000 or more, and is chemically modified with an end-capping group. The cyclic molecule has at least one reactive group that passes through the linear polymer and generates a crosslinking reaction. c. Taking the few-layer graphene composite fluid as the base raw material, adding polyurethane resin in portions to the fluid in a flowing state, and mixing uniformly by shear mixing action to form a graphene polyurethane composite fluid with a viscosity in the range of 1000-1500cps and a particle size distribution D90 of the aggregated paste of less than 10μm. d. The graphene polyurethane composite fluid is continuously coated onto the base support 10 having the intermediate release layer 11 by a method such as knife coating, comma coating, transfer coating, or slot die coating to form a thermally conductive and moisture permeable film layer 20 having a width of at least 1540 cm, a length of at least 1000 m, and a drying temperature of 90-180°C. e. The thermally conductive and moisture permeable film layer 20 is peeled off and wound up, and then independently formed into a thermally conductive and moisture permeable film. Peeling and winding refers to winding the thermally conductive and moisture permeable film layer 20 in the reverse direction onto a paper roll of a certain size under a certain tension, where the tension is 3 kg and the size of the paper roll is less than 6 in. The thermally conductive and moisture permeable film after peeling and winding is left to age at room temperature for 24 hours, and the thickness of the thermally conductive and moisture permeable film after aging is in the range of 15-40 μm and the basis weight is in the range of 20-50 gsm.

[0012] <Example 1> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 1.3 / 2, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 27, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 ° C, and the effective loading amount of graphene is 3%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20 m / min, the tension is less than 3 kg, the size of the paper roll is less than 6 in, the thickness of the thermally conductive and moisture permeable film is 20 μm, the basis weight is 22 gsm, the horizontal thermal conductivity coefficient is 3.04 W / mK, the vertical thermal conductivity coefficient is 0.11 W / mK, and the moisture permeability is 50,000 g / m 2 / 24h, water resistance is 10000mmH 2 O, and the visible light transmittance is 0.5%.

[0013] <Example 2> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 0.8 / 1.2, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 13.75, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 ° C, and the effective loading amount of graphene is 5%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 22gsm, the horizontal thermal conductivity coefficient is 3.42W / mK, the vertical thermal conductivity coefficient is 0.22W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, visible light transmittance is 0.3%, and tensile strength is 285Kgf / cm 2and the breaking elongation is 326%.

[0014] <Example 3> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 0.6 / 0.9, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 13, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 °C, and the effective loading amount of graphene is 7%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 22gsm, the horizontal thermal conductivity coefficient is 4.03W / mK, the vertical thermal conductivity coefficient is 0.19W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, the visible light transmittance is 0.1%, and the tensile strength is 268Kgf / cm 2 and the breaking elongation is 281%.

[0015] <Example 4> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 0.4 / 0.6, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 9, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 °C, and the effective loading amount of graphene is 10%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 23gsm, the horizontal thermal conductivity coefficient is 4.35W / mK, the vertical thermal conductivity coefficient is 0.22W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, the visible light transmittance is 0%, and the tensile strength is 216Kgf / cm 2 and the breaking elongation is 179%.

[0016] <Example 5> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 0.3 / 0.4, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 5.85, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 °C, and the effective loading amount of graphene is 15%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 24gsm, the horizontal thermal conductivity coefficient is 5.00W / mK, the vertical thermal conductivity coefficient is 0.16W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, the visible light transmittance is 0%, and the tensile strength is 152Kgf / cm 2 and the breaking elongation is 97%.

[0017] <Example 6> a. Few-layer graphene, surfactant, and solvent are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5 nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1 μm to 1.5 μm, the optimal distribution is in the range of 0.3 μm to 0.8 μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. b. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added in sequence to the high-concentration few-layer graphene dispersion paste in a fluid state, followed by high-speed stirring to form a homogeneously flowing few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / SA2405P-20 / OK-412 are mixed in a ratio of 10 / 0.2 / 0.3, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. c. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 4.2, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 1000-1500cps. d. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200 gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15 m / min, the width of molding is at least 1540 cm, the length of molding is at least 1000 m, the drying temperature of molding is in the range between 90-180 °C, and the effective loading amount of graphene is 20%. e. Perform a peeling and rewinding process on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of rewinding is 15-20 m / min, the tension is less than 3 kg, the size of the paper roll is less than 6 in, the thickness of the thermally conductive and moisture permeable film is 20 μm, the basis weight is 25 gsm, the horizontal thermal conductivity coefficient is 9.19 W / mK, the vertical thermal conductivity coefficient is 0.16 W / mK, and the moisture permeability is 50,000 g / m 2 / 24h, water resistance is 10000mmH 2 O, and the visible light transmittance is 0%.

[0018] <Comparative Example 1 (graphene not added)> 1. The raw materials such as polyurethane resin and composite additives are prepared as a polyurethane resin composite fluid in a high-speed mixing step. The composite additives include polyrotaxane SA2405P-20 and silicon dioxide powder OK-412, and the polyurethane resin is in a uniformly flowing state after a pre-dispersion process for 20 minutes. After mixing polyurethane resin / SA2405P-20 / OK-412 in a ratio of 100 / 0.4 / 0.5, it is uniformly dispersed by high-speed mixing method, and a high-speed homogenization process is carried out to form a uniformly flowing polyurethane resin composite fluid. The rotation speed of the stirring reaches 2500 rpm, the diameter of the die head is 6 cm, the distance between the die heads is 1 mm, the processing time is 1 hour, the solid content of the polyurethane resin is 95%, and the viscosity ranges between 3000-5000 cps. 2. A polyurethane resin composite fluid is continuously coated on a base support having a peeling force to form a polyurethane thin film layer. The base support is a release paper having a release layer on its surface, and the basis weight is 190-200gsm. The polyurethane resin composite fluid is continuously coated on the release layer surface of the above-mentioned release paper by knife coating method, and a polyurethane thin film layer is formed with the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product with one coating, the linear speed of coating is 10-15m / min, the width of molding is at least 1540cm, the length of molding is at least 1000m, and the drying temperature of molding is in the range between 90-180℃. 3. A peeling and winding process is carried out on the polyurethane film layer to obtain an independently formed polyurethane film. The process conditions of the peeling and winding step are: unwinding linear speed is 15-20m / min, tension is less than 3kg, paper roll size is less than 6in, polyurethane film thickness is 20μm, basis weight is 21gsm, horizontal thermal conductivity coefficient is 0.17W / mK, vertical thermal conductivity coefficient is 0.17W / mK, moisture permeability is 70000g / m 2 / 24h, water resistance is 10000mmH 2 O, visible light transmittance is 95%, and tensile strength is 362Kgf / cm 2and the breaking elongation is 457%.

[0019] <Comparative Example 2 (Polyrotaxane not added)> 1. Few-layer graphene, surfactants, and solvents are polished, sheared, and dispersed at high speed to prepare a high-concentration few-layer graphene dispersion paste. The carbon content of the graphene is ≧99%, the thickness of the graphene is ≦2.5nm, the average distribution of the diameter of the graphene flakes is in the range of 0.1μm-1.5μm, the optimal distribution is in the range of 0.3μm-0.8μm, the oxygen content of the surface is <0.1%, and after the pre-dispersion process is carried out for 20 minutes, a high-concentration few-layer graphene dispersion paste with a uniform distribution is produced, with the concentration difference between the top and bottom of the tank being 5% or less. 2. Add silicon dioxide powder OK-412 to the fluidized high-concentration few-layer graphene dispersion paste, then continue to stir at high speed to form a homogeneously fluidized few-layer graphene composite fluid. The high-concentration few-layer graphene dispersion paste / OK-412 is mixed in a ratio of 10 / 0.3, the effective graphene loading is 20%, the viscosity is in the range of 5000-10000cps, and the particle size distribution D90 of the paste is less than 15μm. 3. A graphene polyurethane composite fluid is prepared by mixing the few-layer graphene composite fluid with raw materials such as polyurethane resin. The solid content of the polyurethane resin is in the range of 15-20%, and the viscosity is in the range of 800cps-1500cps. The few-layer graphene composite fluid / polyurethane resin is subjected to a high-speed homogenization process with a weight ratio of 1 / 9.6, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, the processing time is 1 hour, the effective solid content of the graphene polyurethane composite fluid is in the range of 15-18%, and the flow viscosity is in the range of 2000-4000cps. 4. Continuously coating the graphene polyurethane composite fluid on a base support having a peeling force to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight is 190-200gsm, and the graphene polyurethane composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15m / min, the width of molding is at least 1540cm, the length of molding is at least 1000m, the drying temperature of molding is in the range between 90-180℃, and the effective loading amount of graphene is 10%. 5. A peeling and rewinding process is carried out on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of winding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 23gsm, the horizontal thermal conductivity coefficient is 3.65W / mK, the vertical thermal conductivity coefficient is 0.20W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, the visible light transmittance is 0.1%, and the tensile strength is 178Kgf / cm 2 and the breaking elongation is 91%.

[0020] <Comparative Example 3 (graphene not added but boron nitride added)> 1. Boron nitride, surfactant and solvent are mixed and ground, sheared and dispersed at high speed to prepare a high-concentration boron nitride dispersion paste. The thickness of boron nitride is ≧30nm, and the average distribution of the particle diameter is in the range of 10μm~30μm. 2. Polyrotaxane SA2405P-20 and silicon dioxide powder OK-412 are added to the high-concentration boron nitride dispersion paste in a fluid state, followed by high-speed stirring to form a uniformly fluid boron nitride composite fluid. The high-concentration boron nitride dispersion paste / SA2405P-20 / OK-412 is mixed in a ratio of 10 / 0.2 / 0.3, the effective amount of boron nitride added is 20%, the viscosity is in the range of 3000-5000cps, and the particle size distribution D90 of the paste is less than 15μm. 3. Prepare boron nitride polyurethane composite fluid through the step of mixing boron nitride composite fluid with raw materials such as polyurethane resin. The solid content of polyurethane resin is in the range between 15-20%, and the viscosity is in the range between 800cps-1500cps. The boron nitride composite fluid / polyurethane resin is carried out in a high-speed homogenization process with a weight ratio of 1 / 9, the rotation speed of the stirring reaches 2500rpm, the diameter of the die head is 6cm, the distance between the die head is 1mm, and the processing time is 1 hour. The effective solid content of the graphene polyurethane composite fluid is in the range between 15-18%, and the flow viscosity is in the range between 1000-3000cps. 4. A base support having a peeling force is continuously coated with a boron nitride polyurethane composite fluid to form a film layer having thermal conductivity and moisture permeability. The base support is a release paper having a release layer on its surface, the basis weight of which is 190-200gsm, and the boron nitride composite fluid is continuously coated on the release layer surface of the release paper by knife coating method, and a film layer having thermal conductivity and moisture permeability is formed on the release paper after drying at high temperature. The continuous coating molding method refers to a method of molding a finished product in one coating, the linear speed of coating is 10-15m / min, the width of the molding is at least 1540cm, and the length of the molding is at least 1000m. The drying temperature of the molding is in the range between 90-180℃, and the effective loading amount of boron nitride is 10%. 5. A peeling and rewinding process is carried out on the thermally conductive and moisture permeable film layer to obtain an independently formed thermally conductive and moisture permeable film. The process conditions of the peeling and rewinding step are: the linear speed of winding is 15-20m / min, the tension is less than 3kg, the size of the paper roll is less than 6in, the thickness of the thermally conductive and moisture permeable film is 20μm, the basis weight is 23gsm, the horizontal thermal conductivity coefficient is 3.1W / mK, the vertical thermal conductivity coefficient is 0.18W / mK, and the moisture permeability is 50000g / m 2 / 24h, water resistance is 10000mmH 2 O, and the visible light transmittance is 70%.

[0021] Next, important values ​​of the above-mentioned Examples 1 to 6 and Comparative Examples 1 to 3 are summarized in Table 1 below. [Table 1]

[0022] As can be seen from the above table, by adding graphene to polyurethane resin (substrate), the thermal conductivity coefficient in the horizontal direction is significantly increased and the transmittance of visible light is significantly reduced. In addition, after graphene (thermal conductive additive) is bonded to the polyurethane thin film, the extensibility of the original polyurethane thin film substrate is reduced. In the prior art method of maintaining the extensibility of the thin film, the film thickness is increased to maintain the tensile strength and breaking elongation of the thin film, but at the same time, there is a problem that the weight of the film and the material cost are also increased. For this reason, in the present invention, polyrotaxane is added to improve the tensile strength and breaking elongation of the polyurethane resin (substrate). As can be seen from a comparison between Examples 2 to 4 and Comparative Example 2 (polyrotaxane not added) in the above table, the effect of improving the tensile strength and breaking elongation of the polyurethane resin (substrate) by adding polyrotaxane is particularly remarkable under the condition of adding graphene with a solid content of 5 to 10 wt%.

[0023] Here, in order to solve the problems of the prior art, the present invention prepares a film having thermal conductivity and moisture permeability, and adds few-layer graphene at a solid content weight ratio of 1 to 30 wt % and polyrotaxane at a solid content weight ratio of 0.05 to 10 wt % to a polyurethane resin for the thermally conductive and moisture permeable film. In addition to imparting moisture permeability and waterproofing to the polyurethane resin, the addition of few-layer graphene increases the thermal conductivity, and the addition of polyrotaxane increases the dispersibility of few-layer graphene, improving the flexibility and extensibility of the polyurethane resin substrate, and maintaining the extensibility of the formed thermally conductive and moisture permeable film without increasing its thickness. The linear chain in the chemical structure of polyrotaxane has many linear alkane groups that improve the affinity at the interface between graphene and polyurethane, improving the dispersion and alignment of graphene in the substrate. At the same time, the cyclic molecules have many reactive groups that react with the polyurethane substrate. During the curing and molding process of the thermally conductive and moisture permeable film, the polyrotaxane undergoes a crosslinking reaction with the polyurethane and the reactive functional groups of the crosslinking agent, generating "mobile crosslinking points" in the material, and the extensibility of the thermally conductive and moisture permeable film reaches 100-200%.

[0024] The thermally conductive and moisture permeable film according to the present invention is as follows: The properties of the formed thermally conductive and moisture permeable film are a thickness in the range of 15-40 μm, a basis weight in the range of 20 gsm-50 gsm, a thermal conductivity coefficient in the planar direction of ≥ 1 W / mK, a thermal conductivity coefficient in the perpendicular direction of ≤ 0.5 W / mK, and a moisture permeability of at least 2000 g / m2 as measured according to the JIS L1099-2012B-1 standard. 2 / 24h, and the water pressure resistance measured based on the JIS L1092B-2009 standard is at least 5000mmH 2 O, the visible light transmittance is <0.5%, and the infrared / ultraviolet ray blocking rate is >99.5%.

[0025] Silicon dioxide for preventing adhesion is further added in an amount of 0.1 to 5 wt% by weight of solid content, and a cross-linking agent for generating a cross-linking effect.

[0026] The preferred solid content weight ratio of the few-layer graphene is 5 to 10 wt %, the preferred solid content weight ratio of the polyrotaxane is 0.1 to 5 wt %, and the preferred solid content weight ratio of the silicon dioxide is 2 to 3 wt %.

[0027] The polyurethane resin has a moisture permeability of at least 10,000 g / m, measured according to the JIS L1099-2012B-1 standard. 2 / 24h, the average molecular weight of the polyrotaxane is 100,000 or more and 500,000 or less, at least 95% of the few-layer graphene has a lateral size of 6,000 to 8,000 nm and a thickness of 2 to 3 nm, and the oxygen content of the few-layer graphene is at least less than 0.1 m%.

[0028] Polyrotaxane comprises a compound of a linear polymer and a cyclic molecule, the linear polymer being the axial molecule in the compound, having a molecular weight of 10,000 or more and being chemically modified with an end-capping group, and the cyclic molecule having at least one reactive group that passes through the linear polymer and initiates a crosslinking reaction with the reactive group of the polyurethane resin or / and the crosslinking agent.

[0029] The main chain polymer of the linear polymer includes copolymers such as polyvinyl alcohol, polyvinylpyrrole, polyethylene glycol, polyvinyl alcohol acetal resin, polydimethylsiloxane, polyamine, polyethyleneimine, polyolefin, polyester, polyvinyl chloride, polystyrene, acrylonitrile styrene copolymer, or derivatives thereof, the end capping group includes a dinitrobenzene group, an adamantane group, or a trityl group, and the cyclic molecule includes a calixarene compound, a cryptand compound, a cyclic aromatic compound, a macrocyclic amine compound, a crown ether compound, or a cyclodextrin compound.

[0030] The linear polymer uses a linear polymer based on polyvinylpyrrole, and the cyclic molecule is cyclodextrin, substituted cyclodextrin, or further introducing reactive groups into the substituted structure to obtain a substituted cyclodextrin compound.

[0031] The reactive groups introduced into the cyclic molecule include hydroxy, carboxy, propylene, methacrylic acid, epoxy, or vinyl groups.

[0032] The reactive groups of the polyurethane resin include carbonyl groups, amine groups, hydroxyl groups, and epoxy groups, and the crosslinking agent is an ester-based polymer compound containing an isocyanate reactive group, including prepolymers, copolymers, or derivatives of toluene diisocyanate, methylene diphenyl diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane 4,4'-diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, etc., and the content of the isocyanate reactive group ranges between 5 and 25%.

[0033] As described above, the present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0034] 10 Base support material 11 Intermediate peeling layer 20 Thermally conductive and moisture permeable film layer

Claims

1. A thermally conductive and moisture-permeable film, comprising: a polyurethane resin containing 1 to 30 wt % of few-layer graphene in a solid content weight ratio and 0.05 to 10 wt % of polyrotaxane in a solid content weight ratio, and the polyurethane resin has moisture permeability and waterproof properties; the addition of the few-layer graphene increases the thermal conductivity; the addition of the polyrotaxane increases the dispersibility of the few-layer graphene and improves the extensibility of the polyurethane resin; and the thermally conductive and moisture-permeable film thus formed maintains its extensibility without increasing its thickness.

2. The properties of the formed thermally conductive and moisture permeable film are a thickness in the range of 15-40 μm, a basis weight in the range of 20 gsm-50 gsm, a thermal conductivity coefficient in the planar direction of ≧1 W / mK, a thermal conductivity coefficient in the perpendicular direction of ≦0.5 W / mK, and a moisture permeability of at least 2000 g / m2 as measured according to the JIS L1099-2012B-1 standard. 2 / 24h, and the water pressure resistance measured based on the JIS L1092B-2009 standard is at least 5000 mmH 2 2. The thermally conductive and moisture permeable film according to claim 1, wherein the thermal conductivity and moisture permeable film has a visible light transmittance of <0.5% and an infrared / ultraviolet ray blocking rate of >99.5%.

3. The thermally conductive and moisture permeable film according to claim 1, further comprising 0.1 to 5 wt % of silicon dioxide for preventing adhesion and a crosslinking agent for generating a crosslinking effect.

4. The thermally conductive and moisture permeable film according to claim 3, characterized in that the preferred solid content weight ratio of the few-layer graphene is 5 to 10 wt %, the preferred solid content weight ratio of the polyrotaxane is 0.1 to 5 wt %, and the preferred solid content weight ratio of the silicon dioxide is 2 to 3 wt %.

5. The polyurethane resin has a moisture permeability of at least 10,000 g / m as measured according to the JIS L1099-2012B-1 standard. 2 / 24h, the average molecular weight of the polyrotaxane is 100,000 or more and 500,000 or less, at least 95% of the few-layer graphene has a lateral size of 6,000 to 8,000 nm and a thickness of 2 to 3 nm, and the oxygen content of the few-layer graphene is at least less than 0.1 m%.

6. The thermally conductive and moisture permeable film according to claim 3, characterized in that the polyrotaxane comprises a compound of a linear polymer and a cyclic molecule, the linear polymer being an axial molecule in the compound, having a molecular weight of 10,000 or more, and being chemically modified with an end-capping group, and the cyclic molecule having at least one reactive group that passes through the linear polymer and generates a crosslinking reaction with a reactive group of a polyurethane resin or / and a crosslinking agent.

7. The thermally conductive and moisture permeable film according to claim 6, characterized in that the main chain polymer of the linear polymer comprises polyvinyl alcohol, polyvinylpyrrole, polyethylene glycol, polyvinyl alcohol acetal resin, polydimethylsiloxane, polyamine, polyethyleneimine, polyolefin, polyester, polyvinyl chloride, polystyrene, a copolymer of acrylonitrile-styrene copolymer or a derivative thereof, the end capping group comprises a dinitrobenzene group, an adamantane group, or a trityl group, and the cyclic molecule comprises a calixarene compound, a cryptand compound, a cyclic aromatic compound, a macrocyclic amine compound, a crown ether compound, or a cyclodextrin compound.

8. The thermally conductive and moisture permeable film according to claim 7, characterized in that the linear polymer is a linear polymer based on polyvinylpyrrole, and the cyclic molecule is cyclodextrin, substituted cyclodextrin, or a substituted cyclodextrin compound obtained by further introducing a reactive group into the substituted structure.

9. 9. The thermally conductive and moisture permeable film according to claim 8, wherein the reactive group introduced into the cyclic molecule includes a hydroxyl group, a carboxyl group, a propylene group, a methacrylic acid group, an epoxy group, or a vinyl group.

10. The thermally conductive and moisture permeable film according to claim 6, characterized in that the reactive groups of the polyurethane resin include carbonyl groups, amine groups, hydroxyl groups, and epoxy groups, and the crosslinking agent is an ester-based polymer compound containing an isocyanic acid reactive group, and includes a prepolymer, copolymer, or derivative thereof of toluene diisocyanate, methylene diphenyl diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane 4,4'-diisocyanate, xylylene diisocyanate, or tetramethyl xylylene diisocyanate, and the content of the isocyanic acid reactive group is in the range of 5 to 25%.

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