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Bamboo strip reinforced novolac resin composites were fabricated using bamboo strips that were treated with varying concentrations of sodium hydroxide solution at a constant filler loading (25%). The mechanical properties of various composites (flexural modulus, toughness, tensile strength, and elastic modulus) were determined. The physical characteristics, such as the wetting ability of the alkali treated reinforcements, were increased because of alkali treatment. With increasing concentrations of alkali, a higher percent loss in weight occurred. The mechanical properties were increased with increasing mercerizing strength. Maximum improvement in properties was achieved with 16 -20% of caustic treated reinforcements. An FTIR study indicated aryl alkyl ether formation with OOH groups of cellulose and methylol groups of novolac resin. Beyond 20% there was degradation in all strength properties because of the failure in the mechanical properties of the reinforcements. A correlation was found to exist between the mechanical properties and the developed morphology.

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The aim of the present study is to synthesize hydroxyapatite from seashell and to explore its biocompatibility in vitro. Nano-crystalline hydroxyapatite (HAp) ceramics were successfully fabricated by a mechanochemical method using clam seashells and phosphoric acid. The CaO and H 3 PO 4 acid at different w.t% ratios i.e. 1:0.75, 1:1.25, 1:1.5 and 1:1.75, were ball milled and then heat treated at 1000 °C for 3 h to complete reactions. The synthesized powders were characterized using x-ray diffraction (XRD), FTIR spectroscopy, scanning electron microscope and high resolution transmission electron microscopy. XRD results showed that the average crystallite size of the powder varies from 53 to 67 nm and crystallinity of powder found to be in the range of 88% and 96%. In vitro biocompatibility studies were carried out using osteoblast (MG63) and fibroblast cells (NIH3T3), demonstrated non-toxic nature of the seashell derived HAp powder.

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