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The present study aims to fabricate the epoxy-based bionanocomposites reinforced with hemp nanocellulose and the evaluation of their mechanical, thermal and dynamic mechanical properties. Nanocellulose from hemp fibres was isolated via the chemo-mechanical method and its bionanocomposites were prepared using the in situ polymerization method. Although many researchers have reported studies on the preparation and characterization of bionanocomposites however, studies on the mechanical, thermal, and dynamic mechanical properties of epoxy-based bionanocomposites reinforced with hemp nanocellulose are still unreported. The mechanical properties (i.e. tensile, flexural, hardness, and impact) and dynamic mechanical properties (i.e. glass transition temperature, damping behaviour, storage, and loss modulus) of the developed bionanocomposites were investigated. Further, the crystalline behaviour and thermal stability were also studied using the X-ray diffraction and thermogravimetric analysis techniques, respectively. The results revealed that an addition of nanocellulose considerably improved the mechanical, thermal, and viscoelastic properties of the bionanocomposites. As much as 52.17%, 48.17%, 89.08%, and 15.67% improvements in the tensile strength, flexural strength, impact strength, and hardness, respectively, for the 2 wt.% nanocellulose composites were found over the epoxy matrix.

Nanocellulose of hemp fibers was obtained by employing the chemomechanical technique, which included three stages of chemical treatments followed by mechanical grinding. Morphological analysis of untreated, treated, and nanocellulose of hemp fibers was performed by field emission scanning electron microscopy. Further, the crystalline behavior of these fibers was also measured by X-ray diffraction and observed a higher crystallinity (80.95%) for the nanocellulose. Furthermore, change in chemical structure of fibers after chemical treatments and mechanical grinding was analyzed by Fourier transform infrared spectroscopy, and elimination of hemicelluloses and lignin was confirmed. Higher thermal stability of nanocellulose was confirmed by thermogravimetric analysis and differential scanning calorimetry analysis. The antibacterial analysis was also performed using Escherichia coli (E. coli) and bacillus bacteria. An excellent antibacterial property was offered by the isolated nanocellulose, which makes it a suitable reinforcement to be used in polymeric films and composites for the packaging applications.

The present study aims to investigate the water absorption property and its effect on the mechanical properties (i.e. tensile, flexural, and impact) of bionanocomposites. The epoxy-based bionanocomposites were prepared by reinforcing the epoxy with 1, 2, 3, 4, and 5 wt% of nanocellulose using in situ polymerization method. The maximum water uptake by bionanocomposites was measured; however, the water absorption behavior was not found in accordance with Fickian’s diffusion model. In the present study, very low water absorption in the range of 0.17–0.34% was offered by bionanocomposites. The results obtained from the present experimental study suggested that there were a maximum degradation of 14.96% in tensile strength, 26.44% in flexural strength, and 55.66% in impact strength for bionanocomposites reinforced with 5 wt% of nanocellulose by water uptake.

Now-a-days, the importance of x-rays is increasing in fields like medical diagnosis, cancer treatment, nuclear fission energy, x-ray scanning machines for airport and railway station entry and in treatment of food for preservation. But the exposure to x-rays will be harmful for the users of such facilities. Doctors, operators and researchers are required to be protected from the high energy ionizing radiations like x-rays and gamma rays.So to protect them, proper shielding is necessary. Numbers of shielding materials are used at workplaces of high radiation regions at nuclear installations.  Most commonly used, shielding material is lead glasses due to its high atomic number (Z=82). This insures high absorption by the shielding material. Recently light polymer sheets of polyvinyl alcohol (PVA) are replacing heavy glass sheets. To prepare lead polymer sheets lead compounds are mixed with polymer. In the present work, we selected to mix lead iodide in polymer composite to analyze its X-ray shielding capability. Polymer composites sheets of lead iodide with PVA were prepared by solution method. These sheets of Polymer composites were subjected to soft x-rays (30 KeV- 60KeV) switching studies at room temperature. These sheets found to provide the x-ray absorption69.6% higher than conventional shielding material like lead and are light in weight too.