Carbon nanotube paper with different polymer composition for laser ablation propulsion.

Abstract

Laser ablation propulsion is an important micro-propulsion system for microsatellites. Polymers with carbon added and carbon-based nanomaterial have been demonstrated as propellants with high impulse coupling coefficient (C_m). Among them, the carbon nanotube film exhibits a low ablation threshold fluence of 25 mJ/cm², which shows its potential for propulsion under low laser fluence. In this study, we investigate carbon nanotube papers (CNTPs) as propellants for laser ablation propulsion. Here four types of CNTPs have been included: S-CNTP (composed of single-walled carbon nanotubes, SWCNTs) and M-CNTP1 (composed of multi-walled carbon nanotubes, MWCNTs) and polymer composited CNTP of M-CNTP2 (30% MWCNTs) and M-CNTP3 (8% MWCNTs). SEM shows that S-CNTP and M-CNTP1 feature a network structure of carbon nanotubes while M-CNTP2 and M-CNTP3 have polymer-filled solid surfaces. Notably, M-CNTP3 exhibited a high C_m of 58.1 µN/W under a laser fluence of 1.09 J/cm². Time-resolved plasma spectroscopy revealed a reduced C₂ Swan band emission for M-CNTP3. Thermogravimetric analysis (TGA-DSC) further showed that the polymer's decomposition temperature contributes to the enhanced C_m value for M-CNTP3. These findings suggest that the performance of CNTP-based composite materials as propellants is closely related to the type and quantity of carbon nanotubes, providing an alternative propellant for microsatellite propulsion under low laser fluence conditions.