Abstract: A heat dissipation structure includes a thermal interface material and a transition layer. The thermal interface material includes a matrix and a plurality of carbon nanotubes dispersed in the matrix. The thermal interface material has a first surface and a second surface opposite to the first surface. The transition layer is positioned on one of the first surface or the second surface of the thermal interface material. A thickness of the transition layer is in a range from about 1 nanometer to about 100 nanometers. The transition layer is in contact with the carbon nanotubes of the thermal interface material. An interface thermal resistance between the transition layer and the heat source is less than that between the plurality of carbon nanotubes and the heat source. The present application also relates to a heat dissipation system adopting the heat dissipation structure.

Abstract: An electrothermal actuator includes at least one connecting portion; at least two operating portions; and at least two electrodes. Each of the at least one connecting portion and the at least two operating portions includes a flexible polymer layer and a carbon nanotube paper. A thickness ratio of the carbon nanotube paper and the flexible polymer layer ranges from 1:7 to 1:10. A density of the carbon nanotube paper is greater than 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than ten times that of the flexible polymer layer. A conductivity of the at least two operating portions along the current direction ranges from 1000 S/m to 6000 S/m. A conductivity of the at least one connecting portion along the current direction is greater than 6000 S/m.

Abstract: An electrothermal composite material includes a flexible polymer layer and a carbon nanotube paper stacked on the flexible polymer layer. The carbon nanotube paper is at least partly embedded into the flexible polymer layer. A thickness ratio of the carbon nanotube paper and the flexible polymer layer is in a range from about 1:7 to about 1:10. A density of the carbon nanotube paper is greater than or equal to 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than or equal to ten times that of the flexible polymer layer. A conductivity of the carbon nanotube paper along a first direction is in a range from about 1000 S/m to about 6000 S/m. An electrothermal actuator is also provided.

Abstract: A method for making an electrothermal actuator requires a carbon nanotube paper being provided. The carbon nanotube paper is cut along a cutting-line to form a patterned carbon nanotube paper. At least two electrodes are formed on the patterned carbon nanotube paper. Finally, the electrothermal actuator is obtained by forming a flexible polymer layer on the patterned carbon nanotube paper.

Abstract: An electrothermal actuator includes at least two operating portions and at least two electrodes. The at least two operating portions are electrically connected with each other to define at least one conductive path. Each of the at least two operating portions comprises a flexible polymer layer and a carbon nanotube paper. A thickness ratio of the carbon nanotube paper and the flexible polymer layer ranges from 1:7 to 1:10. A density of the carbon nanotube paper is greater than or equal to 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than or equal to ten times that of the flexible polymer layer. A conductivity of the carbon nanotube paper along a current direction of the at least two operating portions is in a range from about 1000 S/m to about 6000 S/m.

Abstract: An electrothermal actuator includes at least two operating portions and at least two electrodes. The at least two operating portions are electrically connected with each other to define at least one conductive path. Each of the at least two operating portions comprises a flexible polymer layer and a carbon nanotube paper. A thickness ratio of the carbon nanotube paper and the flexible polymer layer ranges from 1:7 to 1:10. A density of the carbon nanotube paper is greater than or equal to 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than or equal to ten times that of the flexible polymer layer. A conductivity of the carbon nanotube paper along a current direction of the at least two operating portions is in a range from about 1000 S/m to about 6000 S/m.

Abstract: An electrothermal actuator includes at least one connecting portion; at least two operating portions; and at least two electrodes. Each of the at least one connecting portion and the at least two operating portions includes a flexible polymer layer and a carbon nanotube paper. A thickness ratio of the carbon nanotube paper and the flexible polymer layer ranges from 1:7 to 1:10. A density of the carbon nanotube paper is greater than 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than ten times that of the flexible polymer layer. A conductivity of the at least two operating portions along the current direction ranges from 1000 S/m to 6000 S/m. A conductivity of the at least one connecting portion along the current direction is greater than 6000 S/m.

Abstract: An electrothermal composite material includes a flexible polymer layer and a carbon nanotube paper stacked on the flexible polymer layer. The carbon nanotube paper is at least partly embedded into the flexible polymer layer. A thickness ratio of the carbon nanotube paper and the flexible polymer layer is in a range from about 1:7 to about 1:10. A density of the carbon nanotube paper is greater than or equal to 0.5 g/cm3. A thermal expansion coefficient of the carbon nanotube paper is greater than or equal to ten times that of the flexible polymer layer. A conductivity of the carbon nanotube paper along a first direction is in a range from about 1000 S/m to about 6000 S/m. An electrothermal actuator is also provided.

Abstract: A method for making an electrothermal actuator requires a carbon nanotube paper being provided. The carbon nanotube paper is cut along a cutting-line to form a patterned carbon nanotube paper. At least two electrodes are formed on the patterned carbon nanotube paper. Finally, the electrothermal actuator is obtained by forming a flexible polymer layer on the patterned carbon nanotube paper.

Abstract: A heat dissipation structure includes a thermal interface material and a transition layer. The thermal interface material includes a matrix and a plurality of carbon nanotubes dispersed in the matrix. The thermal interface material has a first surface and a second surface opposite to the first surface. The transition layer is positioned on one of the first surface or the second surface of the thermal interface material. A thickness of the transition layer is in a range from about 1 nanometer to about 100 nanometers. The transition layer is in contact with the carbon nanotubes of the thermal interface material. An interface thermal resistance between the transition layer and the heat source is less than that between the plurality of carbon nanotubes and the heat source. The present application also relates to a heat dissipation system adopting the heat dissipation structure.

Abstract: A thermal conductivity measurement apparatus for measuring a thermal conductivity of a one-dimensional material includes a substrate, a vacuum chamber receiving the substrate and four spaced electrodes. The one-dimensional material spans across the four spaced electrodes. A middle part of the one-dimensional material, located between the second and third electrodes, is suspended.

Abstract: A thermal conductivity measurement apparatus for measuring a thermal conductivity of a one-dimensional material includes a substrate, a vacuum chamber receiving the substrate and four spaced electrodes. The one-dimensional material spans across the four spaced electrodes. A middle part of the one-dimensional material, located between the second and third electrodes, is suspended.

Abstract: A method for measuring a thermal conductivity of a one-dimensional material is provided.

Abstract: A heat dissipation structure includes a thermal interface material and a transition layer. The thermal interface material includes a matrix and a plurality of carbon nanotubes dispersed in the matrix. The thermal interface material has a first surface and a second surface opposite to the first surface. The transition layer is positioned on one of the first surface or the second surface of the thermal interface material. A thickness of the transition layer is in a range from about 1 nanometer to about 100 nanometers. The transition layer is in contact with the carbon nanotubes of the thermal interface material. An interface thermal resistance between the transition layer and the heat source is less than that between the plurality of carbon nanotubes and the heat source. The present application also relates to a heat dissipation system adopting the heat dissipation structure.

Abstract: A thermal conductivity measurement apparatus for measuring a thermal conductivity of a one-dimensional material includes a substrate, a vacuum chamber receiving the substrate and four spaced electrodes. The one-dimensional material spans across the four spaced electrodes. A middle part of the one-dimensional material, located between the second and third electrodes, is suspended. The present disclosure further provides a method for measuring the thermal conductivity of the one-dimensional material.

Abstract: A CNT composite (10) includes a matrix (14) and a number of CNTs (12) embedded in the matrix. The matrix has a surface (102) and an opposite surface (104). Head portions of the respective CNTs are consistently oriented, parallel to the surfaces of the matrix. A method for manufacturing the composite includes (a) providing a substrate and depositing a catalyst film on the substrate; (b) forming the array of CNTs via the catalyst film on the substrate; (c) immersing the CNTs in a liquid matrix material, infusing the liquid matrix material into the array of CNTs; (d) taking the carbon nanotubes with the infused matrix out of the liquid matrix; (e) pressing the still-soft matrix and the CNTs therein, in order to arrange the CNTs consistently and parallel to the surfaces of the matrix; and (f) solidifying and peeling away the matrix to produce the CNT composite.

Abstract: A CNT composite (10) includes a matrix (14) and a number of CNTs (12) embedded in the matrix. The matrix has a surface (102) and an opposite surface (104). Head portions of the respective CNTs are consistently oriented, parallel to the surfaces of the matrix. A method for manufacturing the composite includes (a) providing a substrate and depositing a catalyst film on the substrate; (b) forming the array of CNTs via the catalyst film on the substrate; (c) immersing the CNTs in a liquid matrix material, infusing the liquid matrix material into the array of CNTs; (d) taking the carbon nanotubes with the infused matrix out of the liquid matrix; (e) pressing the still-soft matrix and the CNTs therein, in order to arrange the CNTs consistently and parallel to the surfaces of the matrix; and (f) solidifying and peeling away the matrix to produce the CNT composite.