The effect of polyhedral oligosilsesquioxanes (POSS) on cavitation resistance of hybrid acrylate films

Cavitation erosion of hybrid acrylate composite films with polyhedral oligosilsesquioxanes (POSS) was investigated in this study. The hybrid films are made with 1, 3 and 5 wt% of POSS reagents containing: (a) hydroxyl (POSS-M), (b) both hydroxyl and allyl (POSS-M-A) and (c) methacryloyl groups (POSS-MCl). Addition of 5 wt% POSS-M-A caused the highest microhardness increase for 49.8%, in comparison to the pure matrix material. Cavitation resistance of hybrid films, estimated as the time-dependent mass loss, was improved by POSS addition. POSS-M-A addition (5 wt%) contributed to 94% lower mass loss comparing to pure Bis-GMA/TEGDMA film. Scanning electron (SEM) and atomic force microscopy (AFM) showed the lowest surface roughness obtained for composite with POSS-M-A. The improved hardness and wear resistance of the composite films indicated that POSS-M-A filler enhanced interfacial adhesion and reinforcing of the Bis-GMA/TEGDMA matrix