Micelle-like particles based on self-assembly of rod-like FPEEK and coil-like PVA

The self-assembly of a rod-like polymer [hydroxyl-terminated trifluoromethylphenyl-substituted fluorinated poly(ether ether ketone) (FPEEK)] and a coil-like polymer (polyvinyl alcohol, PVA) in water has been studied. It was found that this polymer pair could form micelle-like particles. Hydrogen bonding between the hydroxy groups of rod-like FPEEK and coil-like PVA, and parallel packing of the rod-like FPEEK are the main factors affecting the formation of micelle-like particles. Over a broad range, when the FPEEK/PVA mass ratio or the tetrahydrofolate/H₂O volume ratio is decreased, the diameter of micelle-like particles is decreased. The diameters (around 250 nm) of micelle-like particles measured by scanning electron microscopy and dynamic light scattering are similar, but are different from that measured by transmission electron microscopy (around 150 nm). Thus, it can be concluded that micelle-like particles have a core–shell structure and the cores of micelles are composed of FPEEK, and that the shells of micelles are composed of PVA. When polyethylene glycol was used instead of PVA, micelle-like particles were also formed, but the average diameter was bigger than that of the particles formed by PVA and FPEEK.