Abstract—The goal of this work is to modify surface of calcium carbonate nanoparticles with silica (CaCO₃@SiO₂) via sol-gel process, and to investigate the influence of CaCO₃@SiO₂ on mechanical properties and fracture behavior of poly(lactic acid) nanocomposite. Modified CaCO3@SiO2 nanoparticles were prepared with different Si:Ca ratios. It is found that the Si/Ca wt% was increased with respect to the Si:Ca mole ratio used in the reaction. Incorporating CaCO₃@SiO₂ of 5 wt% in creased elastic modulus, %elongation at break and notched impact strength of PLA nanocomposites. These properties of hydrophilic-modified CaCO₃-poly(lactic acid) nanocomposite was increased with respect to the increasing of SiO₂ con tent on the surface of CaCO3 nanoparticles. This implies that better compatibility between PLA matrix and nano-fillers was achieved after modification surface of CaCO₃ with SiO₂ layers.

Index Terms—Nanocomposite, poly(lactic acid), calcium carbonate nanoparticle, silica, sol-gel process.

B. Nekhamanurak is with the Department of Materials Science and Engineering, Faculty of Engineering and Industrial Technology, Silpakorn University, Thailand (e-mail: bawornkit@windowslive.com).
P. Patanathabutr is with the Department of Materials Science and Engineering, Faculty of Engineering and Industrial Technology, Silpakorn University, Thailand (e-mail: pajaera@su.ac.th).
N. Hongsriphan is with the Department of Materials Science and Engineering, Faculty of Engineering and Industrial Technology, Silpakorn University, Thailand (e-mail: nattakar@su.ac.th).

Cite: B. Nekhamanurak, P. Patanathabutr, and N. Hongsriphan, "Mechanical Properties of Hydrophilicity Modified CaCO₃-Poly (Lactic Acid) Nanocomposite," International Journal of Applied Physics and Mathematics  vol. 2, no. 2, pp. 098-103, 2012.