Preparation And Properties Of Xylan-Based Hydrogels

Hemicelluloses are one of the main components of lignocellulosic biomass,but they are not sufficient utilization because of the complexity of their structure and composition.In this study,hemicelluloses as the raw material are chemically modified to prepare hydrogels by using physical and chemical methods.This research can provide theoretical basis on the application of hemicellulose in interface healing,tissue engineering,cell culture,etc.An economical,convenient,eco-friendly and reproducible approach for the preparation of self-healing xylose-based hydrogels is introduced in this study.Xylose was regard as skeleton,mixed with montmorillonite(MMT)and sodium polyacrylate.The hydrogels with internal tight porous network structure were prepared and connected by hydrogen bonds and intermolecular interactions instead of the traditional covalent bond,which resulted in a rapid self-healing ability of the hydrogel and showed good swelling performance.The compression stress increased with the increasing concentration of modified xylose.Furthermore,the xylose-based hydrogels exhibited admirable thermal stability on account of the added MMT nanoplatelets as an inorganic phase.These results revealed that xylose-based hydrogels had promising applications in many fields,such as interface healing and water humectant.Composite hydrogels were prepared by crosslinking acrylic acid(AA)monomers in the presence of the extended molecular chains of xylan.This new chain extension strategy significantly improved the mechanical performance of hydrogels.The crosslinking density,compression modulus,and swelling capacities ranged from 100 to 1405 g/g of hydrogels were adjusted by changing the contents.Moreover,the biocompatibility test suggested that the xylan-based hydrogels exhibited no toxicity to cells and allowed cell growth.These properties demonstrated that the composite hydrogels have potential applications in the fields of water absorbents,cell culture,and other functional biomaterials.Xylan-based hydrogels were prepared by double network method.The first network was obtained by crosslinking acrylic acid(AA)monomers onto xylan,and then,the first network were immersed into the aqueous of acrylamide with ammonium persulfate and N,N-methylene bisacrylamide.The second network was prepared on the basis of the first work.The double networks crosslinked together and enhanced the strength of the fabricated hydrogel,which resulted in the excellent strength and toughness of the hydrogels,and the maximal compression stress reached up to 24.94 MPa.The double network hydrogel can restore the 97%of original height after compressed 15 times repeatedly,which resulted in less consumption of friction and wear.Therefore,the prepared xylan-based double network hydrogel have potential applications in tissue engineering and joint wears.