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In the present work a new type of benzoxazine was synthesized using caproamine with cardanol and their molecular structure was characterized by FTIR and NMR spectroscopy. The graphene reinforced epoxy-polybenzoxazine nanocomposites was prepared by incorporating varying weight percentages of graphene and benzoxazine to epoxy resin. Data obtained from mechanical study infer the significant improvement in the values of tensile strength, impact strength and flexural strength of the composites reinforced with different weight percentages of benzoxazine and graphene. The values of dielectric constant of composite samples are appreciably enhanced and are higher than that of neat epoxy matrix.Data from SEM, TEM and XRD ascertain the existence of homogeneous distribution of graphene in the composites. Data obtained from thermal, mechanical, dielectric and surface free energy studies infer that 20 wt% Bz-g reinforced composites possesses better properties than those of neat epoxy matrix and other weight percentages of composites.

A new semiorganic material of L-alanine sodium nitrate (LASN) has been synthesized and successfully grown by the slow evaporation solution growth method. The grown crystals have been subjected to various characterization techniques such as single crystal X-ray diffraction studies, FT-IR and laser Raman analyses to determine the crystal structure and functional groups, respectively. Crystalline perfection of the grown crystal was analyzed by the high resolution X-ray diffraction technique (HRXRD). Mechanical behavior of the grown LASN crystal was analyzed by Vicker's microhardness test. Thermogravimetric and differential thermal analyses of the grown crystal revealed that there is no phase transformation in LASN, and its thermal stability was found to be good. The dielectric measurement was made as function of frequency (range 0.2-200 kHz). The growth feature of the LASN crystal was studied by wet chemical etching studies. Lower cutoff wavelength and optical transmission window of LASN crystal was found by UV-vis-NIR studies. Laser damage threshold value was determined to be 15.6 and 11.4 GW/cm 2 , respectively, for single shot and multiple shots, by using 5 ns laser pulses at a 10 Hz repetition rate from a Q-switched Nd:YAG laser with a wavelength of 1064 nm. Second harmonic generation efficiency was determined and is about two times that of KDP crystal.

The present work focuses on the utilization of renewable biomaterial as reinforcement for the development of nanocomposites for high-performance low-k microelectronic applications. In the present work, rice husk ash (RHA) was chemically treated and processed to obtain two-dimensional mesoporous silica (SBA-15), which was functionalized using 3-glycidoxypropyl trimethoxy silane through sonication process. The surface functionalized SBA-15 (F-SBA-15) with varying weight percentages (1, 3, and 5 wt%) was incorporated into the epoxy resin. The resulting F-SBA-15-reinforced epoxy composites were characterized by Fourier transform infrared spectroscopy, x-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and impedance analyzer. Among the composite samples with varying loadings, the dielectric behavior of 5 wt% F-SBA-15-loaded composite sample possesses the lowest value of dielectric constant, that is, 2.14 at 1 MHz frequency when compared with that of other samples. Further, the thermal stability was also enhanced to an appreciable extent, when compared with that of the samples with lower F-SBA-15 loadings.

Bottom-contact organic field-effect transistors (OFETs) were fabricated using a polymer gate insulator cross-linked poly(4-vinyl phenol) with regioregular poly(3-hexylthiophene) (RR-P3HT) as an active layer from different organic solvents. With this polymer dielectric, a field-effect mobility of 0.084±0.006cm2V−1s−1 was obtained. Solvents and interfacial properties have pronounced effects in determining the crystallinity and device performance of RR-P3HT on the polymer gate layer. Morphology correlation with the charge carrier mobility of RR-P3HT OFETs is investigated. Large nanoscale crystalline island densities of this polymer play an important role in the high charge carrier mobility of devices.