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Journal of Polymer & Composites Review Article

Hybrid Polymer Composites Reinforced with Coconut Shell Fillers and Silica Fume: Synergistic Effects of Industrial By-Products : A Comprehensive Review

  1. Manju. K Department of Civil Engineering, Vels Institute of Science, Technology & Advanced studies, Chennai
  2. Kalyana Chakravarthy P.R Department of Civil Engineering, Vels Institute of Science, Technology & Advanced studies, Chennai

Abstract

The increasing requirement of sustainable and high-performance engineering materials has led to increased research in hybrid polymer composites comprising sustainable fillers in the form of renewable biomass or industrial by-products. Among the various bio-fillers that exist, coconut shell filler is gaining much prominence due to its low density, high content of lignin, hardness, and abundance as agricultural waste. Another industrial by-product that is rich in amorphous silica and possesses high potential for improving the mechanical and thermal properties of polymer composites is silica fume. The combination of these sustainable fillers in polymer composites represents an excellent option for developing eco-friendly composites with enhanced performance properties, along with waste utilization and conservation of resources. This review article highlights some of the important advancements in hybrid polymer composites reinforced with coconut shell fillers and silica fume.

The effects of these hybrid fillers on tensile, flexural, impact, hardness, wear, thermal stability, water absorption, and microstructure behavior are explained in detail by the use of information provided from the literature. In addition, advanced analytical methods such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) are analyzed in terms of the mechanisms that govern the composite behavior. Lastly, the existing difficulties concerning dispersion, compatibility, moisture sensitivity, and mass production issues associated with hybrid polymer composites are pointed out, along with the future perspectives of the area, which include the utilization of nanofillers, biopolymers, additive manufacturing, and circular materials design.

Keywords

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