Synthesis and characterization of novel biodegradable superabsorbent hydrogels based on chitin and succinic anhydride

Synthesis and characterization of a novel super-absorbent based on wheat straw

“…It has good commercial and environmental value with the advantages of low cost, renewable and biodegradable polysaccharides for deriving super-absorbents (Pourjavadi and Mahdavinia, 2006;Yoshimura et al, 2005). Recently, a series of new superabsorbents characterized by eco-friendliness and biodegradability were made from some natural materials, such as starch, cellulose, chitosan (Lanthong et al, 2006;Peng et al, 2008;Farag and Al-Afaleq, 2002;Wu et al, 2008), which were used to react through radical graft polymerization with vinyl monomers and crosslinking agent.…”

Preparation, characterization and properties of superabsorbent nanocomposites based on natural guar gum and modified rectorite

“…Thus far, many kinds of materials have been used for preparing superabsorbents, among them the naturally available resources such as polysaccharides and inorganic clay minerals have shown particular advantages and drawn considerable attention (Ray & Bousmina, 2005). The utilization of low cost, annually renewable and biodegradable polysaccharides for deriving superabsorbents has offered commercial and environmental superiorities (Pourjavadi, Barzegar, & Mahdavinia, 2006;Yoshimura, Uchikoshi, Yoshiura, & Fujioka, 2005), and the incorporation of inorganic clays or their modified products has also improved the performance of the resultant materials and further reduced the production cost . Presently, the natural polysaccharides including starch (Lanthong, Nuisin, & Kiatkamjornwong, 2006;Li, Zhang, & Wang, 2007), cellulose (Suo, Qian, Yao, & Zhang, 2007), chitosan (Chen, Liu, Tan, & Jiang, 2009;Liu, Wang, & Wang, 2007b), alginate (Hua & Wang, 2009;Pourjavadi, Ghasemzadeh, & Soleyman, 2007a) and gelatin (Pourjavadi, Hosseinzadeh, & Sadeghi, 2007b) have been used for deriving superabsorbents, and the resultant materials have also shown potentials as substitutes for existing petroleum-based superabsorbent materials.…”

Hydrogels of cellulose acetate crosslinked with pyromellitic dianhydride: part I: synthesis and swelling kinetics

“…9,11 Some studies show that the percentage of water absorbed by hydrogels at equilibrium (%Seq) can vary with the gel history, changes in the hydrophilic character of the network or in temperature, pH and radiation dosages (during synthesis), structural changes of the polymeric network, type and amount of solvent used for the synthesis as well as degree of crosslinking. 2,3,[5][6][7][8]10,[12][13][14][15] By determining %Seq, important parameters such as diffusion coefficient, relaxation mechanism, swelling kinetics, mixing enthalpy and the molar mass between network points can be obtained. 3,5,6,10 Water molecules are known to act as plasticizers and, in fact, during water absorption, a glass-rubber transition is observed in the hydrogel which results in a decreasing glass transition temperature of the material.…”