Effect of reinforcement of sustainable β‐CaSiO₃ nanoparticles in bio‐based epoxy resin system

Abstract

The b-CaSiO 3 nanoparticles (NPs) were prepared using calcium carbonate from egg shells and silica as precursors. These NPs were incorporated (1-4 wt %) into bio-based epoxy resin to fabricate nanocomposites. Thermal and mechanical tests were carried out on these composites. The results of dynamic mechanical analysis showed significant improvement in the storage modulus of 1 and 2 wt % composites. The thermomechanical analysis data revealed 19 and 20% of reduction in coefficient of thermal expansion for 1 wt % of CaSiO 3 before and after glass transition as compared to the neat epoxy system. Thermogravimetric analysis results also showed delayed thermal degradation of the composites by significant amounts (17-35 C) for 5% of decomposition, a proportional increase in residues corresponding to the loading concentrations. The flexure tests showed significant improvements in strength (17-36%), modulus (5-33%), and toughness for 1-4 wt % of reinforcement of b-CaSiO 3 NPs. Theoretical calculations of the reinforcement effect on the flexure modulus of the composites agree well with the experimental values. The scanning electron micrograph of the fractured surfaces revealed better interfacial interactions in the composites and enhancements in crack path deflections over the neat specimen.

Eggshell reinforced biocomposite—An advanced “green” alternative structural material

“…The CTEs after the Tg region also ranged from 3% to 9% reduction over that of the neat as shown in Table . Similar results have been reported in CaSiO 3 /SSE nanocomposites . Also, a study of CaCO 3 /bioplast showed improved dimension stability because of stiffer and deformation resistant CaCO 3 NPs which tend to restrict the motion of chain segments of the polymer …”

“… Hence, thermoplastic polymer reinforcement with CaCO 3 fillers has been well investigated but not much studies have been conducted with the filler in the current commercial bio‐based thermosetting resins. Current research focus in green material design has intensified the use of bio‐sourced fillers in biopolymer modification for enhancement of mechanical properties . The Super Sap ® 100/1000 epoxy (SSE) formulation currently has the highest plant‐sourced renewable materials (∼37%) .…”

Bio‐inspired “green” nanocomposite using hydroxyapatite synthesized from eggshell waste and soy protein

“…Tiimob et al . used eggshell derived β ‐CaSiO 3 nanoparticles to modify thermal and mechanical properties of bio‐based epoxy resin system (Super sap ® 100/1000) . Incorporation of just 3 wt % β ‐CaSiO 3 nanoparticles in the resin systems improved the flexural modulus (∼33%) and flexural strength (∼36%) significantly.…”

Pyrolysis oil substituted epoxy resin: Improved ratio optimization and crosslinking efficiency

“…Valuable reviews on bio-based epoxy systems to date can be found in the literature. Most recently, Tiimob et al 17 has reinforced a bio-based ER with sustainable b-CaSiO 3 nanoparticles prepared from egg shell to improve resin properties. These studies mainly focused on the production of bifunctional or polyfunctional alcohol (polyol) from biomass as a substitution of bisphenol A (BPA) for epoxy synthesis.…”