R. V. Gadhave et al.
backbone chain contains hydroxyl groups, making the paper very hydrophilic [2]. Because hydrophilic hydroxyl groups and porous structures absorb water and grease substances, uncoated paper is less valuable when plastic replacement is required [3] [4]. However, there is a scarcity of hydrophobic and oleophobic developments in the paper packaging business. As a result, there is an urgent need to develop strategies for enhancing paper’s grease and water resistance while managing to stay recyclable and cost-effective [3] [5] [6]. High surface energy coatings also improved oil resistance due to a larger quantity of polar components, resulting in stronger grease resistance. After applying the coating, the mechanical characteristics of the paper improved as well. These naturally generated com- pounds provide an alternative to the fluoride-containing materials currently util- ized in the market to increase paper wettability [7]. To address the aforemen- tioned concerns, the coating industry today uses hydrocarbon-based polymers such as polyvinylidene chloride, low-density polyethylene, ethylene acrylic acid, and others to produce oil- and water-resistance paper via surface coating [8]. Due to their low recyclability in current practices, alternatives to present proce- dures are in great demand [9]. Other extensively used coating techniques include fluorinated compounds, which negatively impact human health and aquatic habitats [10]. Given that, food and packaging containers account for around 45% of trash shipped to landfills, with papers and paper products accounting for the vast ma- jority, these chemicals voice issues about microplastic contamination [11]. As health and environmental concerns regarding wax-based, fluorochemical-based, and extrusion-based paper coatings have grown, so has an interest in bioresorb- able and repulpable substitutes for generating water- and oil-repellent coatings. This work describes a plastic-free, fluorine-free, and cost-effective grease and water-resistant paper coating process that uses novel chitosan-graft-polydime- thylsiloxane copolymer and corn starch blends [12]. Scientists are presently fo- cused on bio-based substances like chitosan, poly [lactic acid], wax-based, and protein-based (e.g., whey protein, and casein) and endow paper with specific properties like improved one’s liquid-repugnancy or gas-barrier performances. However, because of several complexities associated with modifying these mate- rials while preserving water impermeability features, these attempts have had limited success, particularly in controlling water blocking capabilities and the high price of the alternatives available [9]. 2. Biobased Paper Coating Global plastic manufacture has grown quickly since the 1950s, generating over 450 million tons of annual output. Despite the benefits and great value provided by plastics, environmental impacts over plastic waste have attracted interna- tional attention. Over 340 million tonnes of waste were generated worldwide, with the packaging industry accounting for approximately 46% of the total [13]. This waste is primarily the consequence of things with a shorter “in-use” life-
DOI: 10.4236/gsc.2022.122002
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Green and Sustainable Chemistry
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