Bucky syntactic foam; multi-functional composite utilizing carbon nanotubes-ionic liquid hybrid

Syntactic foams are closed-cell foams made of hollow microballoons embedded in a polymeric matrix. Carbon nanotube-ionic liquid hybrid was used to develop the first “Bucky syntactic foam”. Improvement in the mechanical and electrical properties of syntactic foam was expected since ionic liquids (ILs) can act as a dispersing and binding agent between carbon nanotubes (CNTs) and the polymeric matrix. Several sets of bucky syntactic foam with various weight fractions of CNTs and IL were prepared. Thermal analysis was carried out by Differential Scanning Calorimetry to ensure samples were fully cured in the presence of IL. Mechanical and electrical properties were also characterized via compression and four-point-probe tests. Results showed that the yield strength, elastic modulus, and energy absorption were improved by choosing the optimized content and ratio of CNTs and IL. Electrical conductivity was also improved up to five orders of magnitude, turning traditionally insulator syntactic foam into a conductive nanocomposite. Bucky syntactic foam illustrated potential to be applied in electronic packaging, structure health monitoring, and EMI-shielding structural composites.