In this present work, the UV shielding behavior of various mol percent of Ce doped mullite samples (CM0–5) were studied. The UV shielding behavior of mullite increasing with respect to ceria and reaching 78% of shielding tendency at 300 nm for CM5 was one of the fascinating outcomes of the study. Based on its exhibition of high shielding tendency, CM5 was chosen and functionalized with Glycidyl terminated silane. Subsequently, the resultant functionalized ceria doped mullite (FCM) was reinforced with polybenzoxazine (PBZ) matrix in order to build up FCM/PBZ nanocomposites. A detailed study was also conducted on the level of influence FCM yields in impacting properties such as UV shielding and thermo‐mechanical nature of FCM/PBZ nanocomposites. Upon analysis, it was determined that the 1.5 wt% FCM reinforced PBZ nanocomposite delivered 89% and 78% shielding efficiency at 300 and 200 nm UV region, respectively. Furthermore studies indicated that it exhibited 34% improved char yield, enhanced tensile strength, that is, 24.81% and 162°C as its glass transition temperature in comparison with neat PBZ matrix and other FCM/PBZ nanocomposites. These results suggest that the Ce doped mullite with high UV shielding properties can be used as a reinforcement to increase the UV shielding tendency of polymeric material which is of industrial significance. POLYM. COMPOS., 39:2073–2080, 2018. © 2016 Society of Plastics Engineers

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Fourteen dimethyldialkoxysilanes are prepared by reacting dimethyldichlorosilane with corresponding alcohols in the liquid phase. Their physicochemical properties are determined by standard methods and their tentative empirical formulae are elucidated. The thermal conductivity values of dimethyldialkoxysilanes are determined using a two slab guarded hot plate apparatus over a temperature range of 30–190°C. The thermal conductivity values of dimethyldialkoxysilanes calculated from empirical equations are found to vary from ‐14% to +19%. Because thermal conductivity is an important parameter in heat transfer calculations, and to minimise the deviation of the values, new equations involving easily measurable ultrasonic parameters have been formulated. The proposed equations have been tested for the series of dimethyldialkoxysilanes, tetraalkoxysilanes and polydimethylsiloxanes. The thermal conductivity values computed from the proposed equations are comparable with experimental thermal conductivity values. Further, an equation involving the calculation of thermal conductivity values at varying temperatures is also proposed.

Titanium incorporated hydroxyapatite preparation was endeavored using TiH2. Titanium has good mechanical properties, good biocompatibility and bioactivity. Titanium incorporated hydroxyapatite material prepared for orthopedic applications were reported to be better mechanical properties. Hydroxyapatite (HAp) was synthesized by wet chemical facile method and after calcination was mixed with TiH2 (5 to 20%).The effect of sintering on phase formation, microstructure, density and porosity of Hap/TiH2was studied by sintering at temperatures from 900°C to 1200°C. The properties of the samples were characterized using X-ray diffraction technique (XRD), Scanning electron microscopy(SEM), Fourier transform spectroscopy (FT-IR), density and porosity. The results from studies showed the presence of β-tricalcium phosphate (β-TCP) and perovskite (CaTiO3) as the major crystalline phases; while minor reaction products like α-TCP and TTCP were also recorded for samples with higher amount of TiH2irrespective of sintering temperatures. Morphology evaluation by SEM revealed the presence of CaTiO3needle structure at temperature till 1000°C, above which it appeared hexagonal due to crystal growth. Functional groups, density and porosity were also studied.