Nanomechanical behaviour of ZrO2 dispersed sisal-based polymeric composites

Alkali-treated sisal fibre-incorporated silanized ZrO2 dispersed unsaturated polyester composites were fabricated with a filler loading of 5, 15, 25, 35, 45 wt%, respectively. The mechanical characterization of the composites was suitably executed at the sub-micron scale using the nanoindentation technique. Various mechanical properties were derived from the standard nanoindentation measurements namely, nanohardness, reduced modulus, recovery index, residual depth, wear rate and indentation creep, respectively. A marked improvement in the mechanical properties of the unsaturated polyester matrix due to the incorporation of the fillers (sisal and/or ZrO2) was observed through indentation-derived parameters namely, nanohardness (similar to 186%), reduced modulus (similar to 175%), recovery index (similar to 62%), wear rate (similar to 63%) and indentation creep (similar to 33%), respectively. A simulated dynamic mechanical analysis was performed using the sinus mode of the nanoindentation technique. A similar enhancement in the dynamic mechanical properties of the matrix was further observed through dynamic mechanical analysis as storage modulus (similar to 71%), loss modulus (similar to 60%), loss factor (similar to 150%) and specific damping coefficient (similar to 200%), respectively.

Automated summary

The study investigated the mechanical properties of alkali-treated sisal fibre-incorporated silanized ZrO2 dispersed unsaturated polyester composites using nanoindentation technique. The results showed a significant enhancement in the mechanical properties of the composites due to the addition of fillers, including nanohardness, reduced modulus, recovery index, wear rate, and indentation creep.