Nano‐dispersion of fluorinated phosphonate‐modified nanodiamond in crystalline fluoropolymer matrix to achieve a transparent polymer/nanofiller hybrid

Well‐dispersed polymer/organo‐modified nanodiamond composites were created using crystalline fluorinated polymers as a matrix. All crystalline fluorinated polymers in this study were heat‐resistant and became transparent via high‐temperature drawing. The polyvinylidene‐fluoride‐based copolymer had a low‐melting point for a fluororesin and was easy to handle. Both fluorocarbon‐ and hydrocarbon‐modified nanodiamond formed well‐dispersed nanocomposites in polyvinylidene‐fluoride‐based fluorocopolymers. The former was prepared due to excellent miscibility, and the latter was obtained by the so‐called “nucleation effect”. In this case, the nucleation effect was induced by the “epitaxial growth” resulting from the affinity between the end of the polymer chain and the modified chain and the similarity between the crystal structures of the modified‐chain molecule and the corresponding polymer. However, fabricating a nanocomposite by combining hydrocarbon‐modified fine particles and a fluorinated polymer is not universally feasible, and this system was unique. Ethylene‐tetrafluoroethylene and perfluoroalkoxyalkane polymers showing high‐melting points cannot form a nanohybrid with hydrocarbon‐modified inorganic nanoparticles. In addition, to form a nanocomposite via melt‐compounding, the desorption temperature of the modified chain of the outermost surface of the organo‐nanodiamond had to be increased. Phosphonic acid containing fluorocarbon chain‐modified nanodiamond satisfied all these requirements. The obtained nanocomposite exhibited enhanced physical properties and unique nanodiamond characteristics. POLYM. COMPOS., 40:E842–E855, 2019. © 2018 Society of Plastics Engineers