Investigation of Calcination of Sepia officinalis Cuttlefish Bone for Reinforcement of Polyvinyl Alcohol Added Nano-Size Montmorillonite

This study aims to investigate the effects on calcination of Sepia officinalis cuttlefish bone (cuttlebone) to enhance reinforcement of polyvinyl alcohol (PVOH) added with nano-size montmorillonite (MMT) blends as potential bio-compatible materials. The polyvinyl alcohol-cuttlebone-montmorillonite nanocomposites were prepared using the solution casting method. Calcined cuttlebone particles were added to the PVOH matrix at different amount of 2 and 5 parts per hundred resin (phr) along with MMT ranging from 1 to 3 phr. Results showed that the tensile strength of cuttlebone-added PVOH-MMT composites at fixed 1 phr MMT was observed to be marginally lower when the cuttlebone increased from 2 phr to 5 phr due to the poor distribution of agglomerated particles. Nevertheless, at higher loading level of MMT, it was found that the addition of cuttlebone at 5 phr exhibited a reinforcing effect in PVOH-MMT blends. This is consistent with the scanning electron microscopy observation, where dispersion of a higher amount of cuttlebone in PVOH-MMT blends was observed to be more homogeneous than a lower amount of cuttlebone. Moreover, based on the X-ray diffraction analysis, the addition of cuttlebone significantly enhanced the intercalation effect of MMT particles in the PVOH matrix. Furthermore, the observation from infrared spectroscopy shows the amount of hydroxyl group for all composites reduced gradually with the increasing amount of cuttlebone. The addition of cuttlebone showed a “red shift” effect, indicating the formation of hydrogen bonds induced by cuttlebone. Lastly, lower enthalpy of melting was detected in relation to higher loading level of cuttlebone embedded in PVOH-MMT blends through differential scanning calorimetry. In conclusion, the blending of cuttlebone in PVOH-MMT is favorable to obtain better properties of composites.