Fabrication of epoxy/silicon nitride nanowire composites and evaluation of their thermal conductivity

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 1; no. 10; pp. 3440 - 3445
• Main Authors: Kusunose, Takafumi, Yagi, Takashi, Firoz, Shakhawat H, Sekino, Tohru
• Format: Journal Article
• Language: English
• Published: 01.02.2013
• Subjects: Heat transfer; Heat treatment; Nanocomposites; Nanomaterials; Nanowires; Polymer matrix composites; Silicon nitride; Thermal conductivity
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c3ta00686g

To improve the thermal conductivity of epoxy resins without losing the insulation, epoxy/silicon nitride (Si sub(3)N sub(4)) nanowire composites were produced. beta -Si sub(3)N sub(4) nanowires were synthesized by the carbothermal reduction and nitridation of a homogeneous mixture of silica (SiO sub(2)), carbon, and a small amount of cobalt viathe vapor-liquid-solid (VLS) mechanism. The ratio of beta to alpha phase in the product Si sub(3)N sub(4) increased with heat-treatment temperature; however, the undesirable SiC also increased. By increasing the nitrogen gas pressure in the heat treatment, the ratio of beta - to alpha -Si sub(3)N sub(4) increased without producing SiC. The epoxy composite containing Si sub(3)N sub(4) nanowires of 60 vol% showed a high thermal conductivity of 9.2 W m super(-1) K super(-1) along the preferred orientation of the nanowires.