Investigation of mechanical properties of sea‐shell‐CaCO3/LDPE composites
Résumé
Mollusk shells are fascinating examples of high performance organic/inorganic bio composite materials that have been the subject of numerous studies1. The investigation of mollusk shell microstructures is of interest in many fields of science2,3. Calcium carbonate(CaCO3)has been commonly used as a filler to toughen polymers because of its reducedcost, abundanceand potentialities as industrial applications4-7.In this study, calcium carbonate particles extracted and ground from threedifferent sea shells (crepidula, oyster and scallops) were studiedby scanning electron microscopy and used as fillers in polyethylene.The structure and mechanical properties of the composites have then been evaluated(Figure 1). Comparisons with commercial calcite and synthesized aragonite,two of the allotropicforms of CaCO3, have been performed.The effect of a stearic acid coating onthe mechanical properties wasalso investigated.Tensile tests and dynamic mechanical analysis (DMA)show improvements in tensile strength and torsion moduluswhen scallops-based fillers are used.Noadditionalimprovement is observed using a stearic acid coating.Itis concludedthat the incorporationof these calcium carbonatebiosourced fillersis able to increase the mechanical properties of the polymers at least in the same way synthetic, purely mineralCaCO3does.