Production and characterization of PEEK/IF-WS2 nanocomposites for additive manufacturing: Simultaneous improvement in processing characteristics and material properties

Abstract

Successful printing of high-performance material with suitable properties using additive manufacturing methods such as Fused Filament Fabrication (FFF) can create many advanced applications in industries. However, the high viscosity of high-performance polymers causes complications during the FFF process and reduces the final print quality. To overcome this challenge, Inorganic Fullerene Tungsten Sulphide (IF-WS2) nanoparticles are applied in this study to enhance the flowability of poly-ether-ketone-ketone (PEEK) without compromising its mechanical and thermal properties. In the first step, different loadings of IF-WS2 nanoparticles are melt compounded with PEEK and the nanocomposites are characterized. SEM and EDX images of fractured surfaces indicate that a good dispersion of nanoparticles is achieved without any pre-treatment or pre-dispersion. A reduction in melt viscosity of 25%, and a simultaneous growth in storage modulus, crystallization and degradation temperature of about 60%, 53% and 100 °C is found with addition of 2 wt% IF-WS2 to PEEK, respectively. This great achievement is mainly ascribed to the unique characteristics of IF-WS2 nanoparticles, acting as both reinforcing and lubricating agents, indicated by a reduction in coefficient of friction. There is no significant increase of crystallization and melting temperatures with the addition of IF-WS2 nanoparticles, which is beneficial in the FFF process. In the second step, the PEEK nanocomposite filaments are printed via FFF. The print quality and mechanical properties of the printed PEEK are also improved with the incorporation of IF-WS2 nanoparticles. Hence, incorporation of IF-WS2 nanoparticles into PEEK via melt compounding is an effective approach for the development of suitable high-performance engineering materials for FFF.