Performance of a novel, eco‐friendly, cellulose‐based superabsorbent polymer (Cellulo‐SAP): Absorbency, stability, reusability, and biodegradability

Abstract

Superabsorbent polymers (SAPs) have attracted tremendous attention recently, with researchers noting that their high water absorbability is valuable for various applications, especially in agricultural contexts. Two types of materials can be used to produce SAPs: Fossil-based (which are harmful to the environment) and bio-based (which are significantly more environmentally friendly, given their biodegradability and minimal toxic side effects). Although bio-based SAPs are preferable for environmental reasons, their synthesis tends to be time consuming and labour intensive, while their absorption capacity (AC) can be far below expectations. To address these problems, a novel, eco-friendly, cellulose-based superabsorbent polymer (Cellulo-SAP) was developed in this study through facile preparation via free radical synthesis using modified cellulose. Then, the absorbency, thermal/pH stability, reusability, and biodegradability of Cellulo-SAP were evaluated. This new polymer demonstrated reusability as a water reservoir, in addition to high thermal and pH stability.More importantly, Cellulo-SAP achieved an AC of 475 g/g and exhibited superior biodegradability compared to a commercial, fossil-based SAP. Accordingly, these results prove that Cellulo-SAP can be used in agriculture as an effective alternative to fossil-based SAPs.

Synthesis, Characterization, and Swelling Properties of a New Highly Absorbent Hydrogel Based on Carboxymethyl Guar Gum Reinforced with Bentonite and Silica Particles for Disposable Hygiene Products

“…Superabsorbents of petrochemical origin are usually obtained by free-radical polymerization of vinylic monomers with multifunctional cross-linkers. Synthetic polymers present drawbacks such as nonrecyclability, high market price, energy-consuming synthesis processes, toxicity of trace initiators and unreacted monomers, and environmental concerns. , In comparison, natural SAPs are prepared from polysaccharides such as chitin, chitosan, ,, cellulose, , starch, agarose, alginates, tragacanth, , tamarind, and carrageenan . They are in great demand in the market due to the continuous increase in the global population and the average age of people.…”

Superabsorbent Hydrogels in the Agriculture and Reclamation of Degraded Areas

“…Superabsorbents, depending on their chemical composition, can be divided into two groups. The raw materials for production of acrylic SAP are mostly petroleum-based, relatively cheap synthetic copolymers produced from vinyl monomers and chemically modified natural polymers [25,26] based on starch [27][28][29], cellulose [30][31][32][33][34], chitosan [13,[35][36][37], humic acid [38], proteins [39][40][41], alginate [42][43][44][45] agar [46], curdlan [47][48][49], gellan [50], xanthan [51,52] or arabic gum [46,53,54]. It is also possible to produce SAPs as a result of alkaline hydrolysis of polyacrylonitrile waste used for the production of fibres and fabrics [55] or a combination of several processes [56].…”

“…Copolymerisation of natural polysaccharides, such as alginate [42], starch [161], cellulose [30], saccharose or chitosan [190][191][192] with hydrophilic synthetic polymers is one method of producing environmentally friendly polymers.…”

“…Polysaccharides and proteins are most commonly used in the preparation of SAPs due to the availability of raw material on an industrial scale and their biodegradability [11,30,104,152,193,194]. These copolymers can be degraded by natural biological processes, including the action of enzymes, microorganisms and water, transforming into harmless simple compounds that are safe for the environment [27,195].…”

Issue Highlights

“…Accordingly, these results prove that Cellulo‐SAP can be used in agriculture as an effective alternative to fossil‐based SAPs for soil water retention. [ 3 ]…”