Vol.:(0123456789) 1 3 Journal of Polymers and the Environment https://doi.org/10.1007/s10924-020-01756-1 ORIGINAL PAPER Infuence of Eggshell Nanoparticles and Efect of Alkalization on Characterization of Industrial Hemp Fibre Reinforced Epoxy Composites R. Bhoopathi 1  · M. Ramesh 2 © Springer Science+Business Media, LLC, part of Springer Nature 2020 Abstract Nowadays most of the researchers are focusing their research on pollution free environment, bio-degradable nature and balanced ecological aspect while fabricating the composite materials rather than mechanical strengths, costs, processing methodologies, etc. The objective of this experimental study is to analyze the infuence of the bio-based eggshell nanoparti- cles on the thermal and morphological properties of alkali-treated hemp fbre reinforced epoxy composites. The composites were fabricated by hand lay-up process followed by compression molding technique and the properties of composites are analyzed by using thermo-gravimetric analysis, Fourier transform Infra-red spectroscopy, diferential scanning calorimetry and X-ray difraction techniques. The mechanical properties such as tensile, shear, fexural and impact strengths as well as water absorption characteristics of these composites are also investigated. The morphological characteristics were analyzed by scanning electron microscopy analysis. The results clearly showed that the incorporation of eggshell nanoparticles has signifcant infuence on the thermal and morphological properties of alkali-treated hemp fbre composites. Keywords Hemp fbres · Eggshell nanoparticles · Alkali-treatment · Characterization · Thermal properties · Mechanical properties · Morphological studies Introduction In recent years most of the researchers and industries are focusing their interest to develop the natural fbres based composites for several applications in order to reduce the unpleasant environmental conditions [1–4]. The advantages of bio-based nanoparticles are greater extended to improve the strength of the components and to reduce the cost. The natural fbres and bio-fllers are easily degradable, light weight, abundantly available and low cost when compared with manmade fbres and synthetic fllers [5–9]. The hemp, kenaf, coir, cotton, jute, and sisal fbres are used as predomi- nant fbres in fabricating of composites with polymeric or bio-based resin by several researchers and this being used rapidly to improve the mechanical and thermal properties to satisfy the needs of automotive, textile and packing indus- tries. Hemp fbre reinforced composites have fnding appli- cations in the diverse feld ranging from home appliances to aviation industries [10]. The properties of polymeric matri- ces are improved by reinforcing the natural fller materials in the form of nano-size such as eggshell particles, walnut shells, wood particles, and rice and corn husk. Eggshell nanoparticles is one of the cost efective natural fllers than others because it is extracted from shells of bio-waste. The surface treatment of hemp fbre was carried with 5 vol.% of NaoH solution to improve the interfacial bonding between fbre and matrix. Most of the authors reported that, the plant/ natural fbres from hemp, Tapsi, banana, sisal, kenaf, pineapple, palm, jute are used as reinforcement as well as fller materials in dif- ferent polymer composites [11–13]. Gheitha et al. [14] stud- ied the thermal properties of natural fbre reinforced epoxy Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10924-020-01756-1) contains supplementary material, which is available to authorized users. * M. Ramesh mramesh97@gmail.com 1 Department of Mechanical Engineering, Sri Sairam Engineering College, Chennai, Tamil Nadu 600044, India 2 Department of Mechanical Engineering, KIT-Kalaignarkarunanidhi Institute of Technology, Coimbatore, Tamil Nadu 641402, India