Analysis of cellulose based nanocomposites & potential applications Mugdha Dongre ⇑ , V.B. Suryawanshi Department of Mechanical Engineering, Veermata Jijabai Technological Institute, Maharashtra, India article info Article history: Received 31 October 2020 Received in revised form 11 December 2020 Accepted 22 December 2020 Available online 16 February 2021 Keywords: Cellulose nanocomposites Characterization techniques Cellulose nanofibres Potential applications abstract Cellulose based nanocomposites have achieved a lot more attraction in recent years owing to its renewa- bility, good mechanical strength and durability. The cellulose based nanocomposite development process typically involves extraction of cellulose from source materials such as wood, agricultural residue etc., isolation of nanocellulose from the cellulose and reinforcement of nanocellulose in polymers. This review outlines the various chemo-mechanical methods used for extraction of cellulose and for isolation nanocellulose. Also, the different methods used for fabrication of cellulose nanocomposites are discussed in details. Finally, the potential applications of nanocellulose composites different industries such as food and packaging, structural, bio- medical and electronics are also presented. Ó 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Confer- ence on Advances in Materials Research – 2019. 1. Introduction Over recent decades, investigation has been established on using cellulose nanofibres/ cellulose nanocrystals as reinforcing materials in composite structure due to its superabundant accessi- bility in nature, biodegradability, renewability, eco-friendly nature and high strength & stiffness etc. Despite these characteristics, the use of cellulose as a filler material in nanocomposites is restricted due to their hydrophilic nature, low thermal resistance. These obstructions can be handled with some advanced methods such as surface modifications i.e. Acetylation and Silylation treatments. Cellulose is most abundant naturally derived polymer on Earth, having intrinsic stiffness and high crystallinity. It is sustainable, biodegradable resource which can be utilized as a filer material in reinforcing composites [1]. 2. Methods of extraction of cellulose Cellulose is present as whisker like microfibrils in plants, which can be biosynthesized and are structured in particularly linear and parallel manner i.e. Crystalline region and loose, low ordered man- ner i.e. Amorphous region [2]. Cellulose is extracted by Kenaf [2], Oil Palm empty fruit bunches (OPEFB) [3], Agricultural residue of Cocos-nucifera [4], Rubberwood and Rice Husk [5]. 2.1. Alkaline treatment Alkaline method is carried out as a pre-treatment for solubiliz- ing hemicelluloses and removal of lignin, pectin & other waxy sub- strates covering the outmost surface of cell wall. Nazir et al [3] used mixture of Formic Acid & Hydrogen Peroxide to remove lignin & Hemicelluloses instead of Alkaline method. The cleaned & dried fibres are dewaxed using mixture of Toluene-ethanol in ratio of 2:1 for 4 to 6 hrs. in Soxhlet apparatus. [3,4]. Bleaching were done four times in sodium chlorite (NaClO2) solution under acidic conditions (pH 4 to 5) at 70 °C for 1 hr. The fibers were then washed with deionized water before 6 wt% potassium hydroxide (KOH) solution was added to the fibers at 20 °C for 24 hrs. [4]. The bleaching pro- cess is followed by hydroxide (delignification) treatment which mainly used by researchers [5,7,8]. Alkaline treatment can improve surface roughness and improves number of celluloses on surface of fibres [9]. Successful dismissal of Lignin and additional impurities can be assured by white color of fibre [10]. 2.2. Acid hydrolysis Acid Hydrolysis is effectively used method for extraction of cellulose whiskers. Investigation has been conducted to check influence of processing parameters such as, nature and concentra- tion of Acid, time and temperature of hydrolysis method and fibre to acid ratio on the mechanical, physiochemical and thermal prop- erties. During Acid treatment, the unstructured region is degraded yet the crystalline region remains intact. Rashid et al. [11] https://doi.org/10.1016/j.matpr.2020.12.943 2214-7853/Ó 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Advances in Materials Research – 2019. ⇑ Corresponding author. E-mail addresses: mugdhamts2@outlook.com (M. Dongre), vbsuryawanshi@me. vjti.ac.in (V.B. Suryawanshi). Materials Today: Proceedings 45 (2021) 3476–3482 Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr