Synthesis and Characterization of Carbon Nanofiber Sheet Reinforced Polyvinyl Alcohol (PVA) Composite

Carbon nanofibers (CNF) reinforced polymer composites with lightweight, sustainability of large deformation, oil and corrosion resistance can have positive impact on a wide range of applications. However, this type of composites is still under extensive research due to the difficulties in material handling and processes scale up. To improve processing control and reproducibility for large-scale engineering applications, cost effective carbon nanofibers (CNFs) in form of interconnected porous sheet (Buckypaper) were used as nano fillers. Microstructure of fiber sheet and composite, static mechanical and dynamic mechanical properties of CNF reinforced polyvinyl alcohol (PVA) have been investigated. The effect of dimethyl sulfoxide (DMSO) solvent has been compared to water and shows better improvement in wetting and forming covering layer on the carbon surface. Our sample fabrication technique forms a layered structure where the interfacial debonding between outside PVA layer and inner composite layer can lead to negative impact on static mechanical property. However, the static Mechanical measurements on the composite samples still show significant modulus enhancement that doubles that of pure PVA with the same fabrication process and condition. DMA and DSC measurements show that the unique sandwich-like composite samples have improved storage modulus changing Tg of PVA.