ALIGNMENT OF CARBON NANOTUBE SHEETS BY APPLYING PREPREGGING AND MECHANICAL STRETCHING STRATEGY

摘要

Carbon nanotube (CNT) sheets produced by floating catalytic synthesis were candidates for advanced composite fabrication, and perfect CNT alignment was needed to realize superior mechanical performance. Beyond direct mechanical stretching, new strategy was developed. After prepregging the sheet with bismaleimide resin solution, mechanical stretching was applied. The formula and concentration of bismaleimide resin were altered to investigate the influence of prepregging on stretching behavior. Experiments indicated that resin with softening point closer to room temperature led to higher stretching ratio. Finally, stretched sheets were cured to fabricate composites, and tensile tests were conducted. Composites fabricated with higher stretching ratio could achieve higher tensile strength and modulus, which could be attributed to enhanced CNT bundle alignment and interfaces.