以PEEK为基体,石墨化多壁碳纳米管为增强剂,运用超声分散、熔融共混、模压成型法在不同温度条件下制备碳纳米管增强聚醚醚酮型复合材料。利用三点弯曲法、锥形量热法、热重分析(TG)等方法分析不同熔融温度对复合材料的力学性能、阻燃特...以PEEK为基体,石墨化多壁碳纳米管为增强剂,运用超声分散、熔融共混、模压成型法在不同温度条件下制备碳纳米管增强聚醚醚酮型复合材料。利用三点弯曲法、锥形量热法、热重分析(TG)等方法分析不同熔融温度对复合材料的力学性能、阻燃特性以及热稳定性的影响。结果表明:石墨化多壁碳纳米管的添加能够有效提高PEEK的力学性能以及阻燃性能。400℃温度条件下所制备的试样的弯曲强度最高,达到228.2 MPa,热释放速率峰值(PHRR)最小,为424 k W/m^2,初始氧化温度高达500.3℃,具有较好的热稳定性。展开更多
During the operation of electronic devices,a considerable amount of heat and electromagnetic radiation is emitted.Therefore,the investigation of materials with electromagnetic shielding and thermal management abilitie...During the operation of electronic devices,a considerable amount of heat and electromagnetic radiation is emitted.Therefore,the investigation of materials with electromagnetic shielding and thermal management abilities has significant importance.Hybrid materials of three-dimensional graphene networks containing both carbon nanotubes(CNTs)and SiC whiskers(3D graphene-CNT-SiC)were synthesized.Using an aqueous-phase reduction method for the self-assembly of the graphene oxide,a three-dimen-sional porous graphene structure was fabricated.SiC whiskers,inserted between the graphene layers,formed a framework for longit-udinal thermal conduction,while CNTs attached to the SiC surface,created a dendritic structure that increased the bonding between the SiC whiskers and graphene,improving dielectric loss and thermal conductivity.It was found that the thermal conductivity of the hybrid material reached 123 W·m^(-1)·K^(-1),with a shielding effectiveness of 29.3 dB when the SiC addition was 2%.This result indic-ates that 3D graphene-CNT-SiC has excellent thermal conductivity and electromagnetic shielding performance.展开更多
A 3D nitrogen⁃doped graphene/multi⁃walled carbon nanotube(CS⁃GO⁃NCNT)crosslinked network mate⁃rial was successfully synthesized utilizing chitosan and melamine as carbon and nitrogen sources,concomitant with the incor...A 3D nitrogen⁃doped graphene/multi⁃walled carbon nanotube(CS⁃GO⁃NCNT)crosslinked network mate⁃rial was successfully synthesized utilizing chitosan and melamine as carbon and nitrogen sources,concomitant with the incorporation of multi⁃wall carbon nanotubes and employing freeze drying technology.The material amalgamates the merits of 1D/2D hybrid carbon materials,wherein 1D carbon nanotubes confer robustness and expedited elec⁃tron transport pathways,while 2D graphene sheets facilitate rapid ion migration.Furthermore,the introduction of nitrogen heteroatoms serves to furnish additional active sites for lithium storage.When served as an anode material for lithium⁃ion batteries,the CS⁃GO⁃NCNT electrode delivered a reversible capacity surpassing 500 mAh·g^(-1),mark⁃edly outperforming commercial graphite anodes.Even after 300 cycles at a high current density of 1 A·g^(-1),it remained a reversible capacity of up to 268 mAh·g^(-1).展开更多
文摘以PEEK为基体,石墨化多壁碳纳米管为增强剂,运用超声分散、熔融共混、模压成型法在不同温度条件下制备碳纳米管增强聚醚醚酮型复合材料。利用三点弯曲法、锥形量热法、热重分析(TG)等方法分析不同熔融温度对复合材料的力学性能、阻燃特性以及热稳定性的影响。结果表明:石墨化多壁碳纳米管的添加能够有效提高PEEK的力学性能以及阻燃性能。400℃温度条件下所制备的试样的弯曲强度最高,达到228.2 MPa,热释放速率峰值(PHRR)最小,为424 k W/m^2,初始氧化温度高达500.3℃,具有较好的热稳定性。
文摘During the operation of electronic devices,a considerable amount of heat and electromagnetic radiation is emitted.Therefore,the investigation of materials with electromagnetic shielding and thermal management abilities has significant importance.Hybrid materials of three-dimensional graphene networks containing both carbon nanotubes(CNTs)and SiC whiskers(3D graphene-CNT-SiC)were synthesized.Using an aqueous-phase reduction method for the self-assembly of the graphene oxide,a three-dimen-sional porous graphene structure was fabricated.SiC whiskers,inserted between the graphene layers,formed a framework for longit-udinal thermal conduction,while CNTs attached to the SiC surface,created a dendritic structure that increased the bonding between the SiC whiskers and graphene,improving dielectric loss and thermal conductivity.It was found that the thermal conductivity of the hybrid material reached 123 W·m^(-1)·K^(-1),with a shielding effectiveness of 29.3 dB when the SiC addition was 2%.This result indic-ates that 3D graphene-CNT-SiC has excellent thermal conductivity and electromagnetic shielding performance.
文摘A 3D nitrogen⁃doped graphene/multi⁃walled carbon nanotube(CS⁃GO⁃NCNT)crosslinked network mate⁃rial was successfully synthesized utilizing chitosan and melamine as carbon and nitrogen sources,concomitant with the incorporation of multi⁃wall carbon nanotubes and employing freeze drying technology.The material amalgamates the merits of 1D/2D hybrid carbon materials,wherein 1D carbon nanotubes confer robustness and expedited elec⁃tron transport pathways,while 2D graphene sheets facilitate rapid ion migration.Furthermore,the introduction of nitrogen heteroatoms serves to furnish additional active sites for lithium storage.When served as an anode material for lithium⁃ion batteries,the CS⁃GO⁃NCNT electrode delivered a reversible capacity surpassing 500 mAh·g^(-1),mark⁃edly outperforming commercial graphite anodes.Even after 300 cycles at a high current density of 1 A·g^(-1),it remained a reversible capacity of up to 268 mAh·g^(-1).
