Property Evaluation of Surface ModifiedMWCNTs Reinforced Polymer CompositesUnder Low Earth Orbit EnvironmentConditions

In this paper, the property of multi-walled carbon nanotubes (MWCNTs) reinforced epoxy polymer (CNRP) composites exposed to low earth orbit (LEO) environment are investigated. In order to study tailored CNRP, a surface modification of MWCNTs was tuned to improve interfacial bonding between the nanotubes and the matrix. The surface modification of MWCNTs had been carried out using multifunctional silanes (3-APTES) being popular for the surface treatment of MWCNTs. The corresponding moieties were characterized by Fourier Transform Infrared Spectroscopy and X-ray photoelectron spectroscopy (XPS). The surface modified multiwalled carbon nanotubes reinforced polymer composites were prepared by solution mixing method using mechanical/physical approaches to disperse homogeneously the MWCNTs into the polymer matrix. The sets of specimen series were tested in accelerated LEO simulated space environment. The synergistic environmental factors of the used ground simulation systems were the high vacuum, atomic oxygen (AO), ultraviolet (UV) radiation and thermal cycling. The material properties of CNRP composites before/after exposed to LEO space environment was evaluated through the measurement of mass loss against temperature variation, coefficient of thermal expansion (CTE), total mass loss (TML), tensile strength, thermal emissivity (e). The results indicate that the surface modification of MWCNTs can reduce mechanical properties degradation and enhance thermal stability of CNRP composites with very low MWCNTs content exposed to LEO environment.