High-performance polyketone nanocomposites achieved via plasma-assisted mechanochemistry

Polyketone (PK) is an engineering plastic with excellent impact strength, chemical resistance, barrier properties, and flame retardancy. However, the development of PK nanocomposites with further improved properties obtained via compounding is challenging due to the poor compatibility between PK and nanofillers. Also, since PK is not soluble in common organic solvents, it is difficult to enhance the affinity between components by applying wet chemistry processes widely used to make other composites. Herein, we report an effective solution to improve the compatibility of PK and nanofillers via a completely dry process. The plasma-assisted mechanochemistry (PMC) process can form chemical bonds between polymers and nanofillers, thereby promoting the dispersion of the nanofillers in polymer composites. PK was compounded with graphite nanoplatelets (GNPs) using the PMC process, and the structure and properties of the composites were investigated. The composites displayed greatly improved mechanical and gas barrier properties, and thermal conductivity; compared with conventionally prepared composites having the same GNP content (10 wt%), the composites prepared via the PMC process had 9.7 times higher elongation at break (112.1%), 2.2 times higher impact strength (89.2 J/m), 2.2 times better barrier performance (0.9 g/m²·day), and 2.5 times higher thermal conductivity (1.6 and 13.9 W/mK in the through-plane and in-plane directions). This approach is an innovative route to high-performance polymer nanocomposites, even those constructed from insoluble and incompatible polymers such as PK.