Biodegradation, cytocompatability and performance studies of vegetable oil based hyperbranched polyurethane modified biocompatible sulfonated epoxy resin/clay nanocomposites

Lack of degradability and decrease of landfill sites along with growing water and land pollution problems generate a strong concern about the use of synthetic non-biodegradable polymers. Mesua ferrea L. (Ceylon Ironwood) seed oil based diglycidyl sulfone epoxy resin was modified by the same oil based hyperbranched polyurethane. This hyperbranched polyurethane was prepared by using an A2 + B3 approach using monoglyceride of the oil as one of the components, as reported earlier. The epoxy resin was modified by incorporating three different weight percentages of hyperbranched polyurethane viz. 10, 20 and 30 wt%. The hyperbranched polyurethane treated epoxy system was characterized by FTIR, SEM and XRD techniques. The study of performance characteristics reveals that epoxy modified by 30 wt% HBPU is the best composition. Nanocomposites of 30 wt% HBPU based composition were prepared with different dose levels of organo nanoclay (1, 3 and 5 wt%) and were characterized by using wide angle X-ray diffraction (WAXD), SEM, TEM and FTIR techniques. The nanocomposite shows improvement in performance characteristics with the increase of clay content. The nanocomposite with 5 wt% of clay shows an increase of about 230% in tensile strength with respect to the pristine epoxy system. The biodegradability tested on all the samples by Pseudomonas aeruginosa bacterial strain and they exhibited significant degradation after 30 days of inoculation. Thus the resulted nanocomposites have potential to be used as biodegradable an advanced coating materials.