Natural gum rosin thin films nanopatterned by poly(styrene)-block-poly(4-vinylpiridine) block copolymer

Nanostructured polymeric blends containing renewable gum rosin (GR) were successfully designed using a poly(styrene)-block-poly(4-vinylpiridine) (S4VP) as nanostructuration agent. The thin films were prepared using spin-coating in a one step pathway. As expected, the intermolecular hydrogen bond interactions between gum rosin and poly(4-vinylpiridine) (P4VP) block was confirmed by FTIR. Additionally, the miscibility between these components of the polymeric blends was indicated by a shift of the Tg corresponding to the P4PV block to lower temperature with the increase of the GR in the polymeric GR/S4PV blends. One of the interesting observations of this work is that the introduction of only 20 wt% of S4PV block copolymers is enough to obtain nanostructured blends. The morphology change from worm-like to lamellar long range ordered pattern passed through a fingerprint-like structure with increasing amount of the S4PV block copolymer, which allowed development of novel tuneable nanostructured S4PV-based supramolecular materials employing low cost renewable materials such as easily accessible gum rosin.