RETRACTED: Preparation and characterization of poly(vinyl chloride) calcium phosphate nanocomposites (Retracted article. See vol. 175, pg. 94, 2010)

Calcium phosphate [Ca-3(PO4)(2)] was synthesized by in situ deposition technique and its nano-size (47-97 nm) was confirmed by Transmission Electron Microscopy (TEM). Composites of the filler Ca-3(PO4)(2) (micro and nano) and the matrix poly(vinyl chloride) (PVC) were prepared with different filler loadings (0-5 wt.%) by melt intercalation. The Brabender torque rheometer equipped with an internal mixer was used for the preparation of composites of different formulations. The effect of nano-and microCa(3)(PO4)(2) content on the structure and properties of composites was studied. The nanostructures were studied by wide angle X-ray diffraction (WAXD) and scanning electron microscopy (SEM). The mechanical, thermal and dynamic mechanical properties of PVC/micro- and nano-Ca-3(PO4)(2) composites were characterized using Universal Testing Machine (UTM), Thermo Gravimetric Analyzer (TGA) and dynamic mechanical analyzer (DMA). The thermal analysis results showed that the first thermal degradation onset (T-onset) of PVC/nano-Ca-3(PO4)(2) composites was lower as compared with corresponding microcomposites and higher than that of pristine PVC. However, the tensile strength was found to be maximum at 1% of nano-Cal(PO4)(2) and again decreased with increasing loading of nano-Ca-3(PO4)(2). Further storage modulus of PVC/micro- and nano-Ca-3(PO4)(2) composites was decreased with increasing loading while the glass transition temperature increased marginally. (C) 2009 Elsevier B.V. All rights reserved.