The Synthesis Of Chitosan Based Superabsorbent Polymer And Its Properties Test

Water is the source of life.Due to the uneven spatial and temporal distribution of water resources and water pollution,water shortage has become one of the important reasons for restricting China's economic and social development.The development of superabsorbent materials is an effective way to improve the effective utilization of water and to solve the uneven distribution of water resources.With the deepening of research,the application of superabsorbent polymers in other fields has also received extensive attention.The 21 st century is known as the Ocean Century.Strengthening the use and development of the ocean is related to national security and long-term development.China is a big maritime country with abundant marine resources.How to use marine resources is one of the important issues in front of us.Chitosan can be prepared by chemical modification to prepare a superabsorbent polymer.The chitosan-based superabsorbent polymer has a certain biological activity in addition to good water absorption and water retention.In this paper,various chitosan derivatives were prepared by using chitosan as raw materials through different chemical modification methods.Then the chitosan derivative was used as the backbone,and the hydrophilic monomer was inserted into the chitosan derivative skeleton by graft copolymerization to prepare a variety of new superabsorbent polymers.The structure of the new superabsorbent polymer was characterized by infrared spectroscopy,solid state NMR,X-ray diffraction,elemental analysis and scanning electron microscopy.The properties of the new superabsorbent resin were tested.The main results were as follows:(1)Aminoethyl chitosan which was a branched chitosan derivative was prepared by using chloroethylamine hydrochloride and chitosan as raw materials,and then a superabsorbent polymer was prepared by using chitosan derivatives as a skeleton.The superabsorbent polymer has good water absorption capacity and water retention capacity,and the maximum water absorption ratio can be about 700 times.The water absorption performance,water retention capacity,water absorption rate and other performances are better than those of the superabsorbent polymer prepared directly from chitosan under the same preparation conditions.The introduction of aminoethyl group provided more graft sites and cross-linking sites for the graft polymerization process.Scanning electron microscopy showed that the new superabsorbent polymer has a more developed and dense pore structure,which can improve the water absorption capacity water absorption rate.The dense network structure also provides good mechanical strength for superabsorbent polymers.(2)A variety of superabsorbent polymers were prepared by grafting copolymerization of acrylic acid and acrylamide onto the framework by chitosan sulfate backbone with different substitution sites.Since the hydroxyl group and the amino group are substituted by a sulfate group,the water absorption capacity of the superabsorbent resin is slightly decreased,but the introduction of-SO3 H having a higher ionization tendency lowers the sensitivity of the superabsorbent resin network to the salt solution,thereby It improves its water absorption capacity in the cationic solution.Chitosan sulfates with different substitution sites also have an effect in the preparation of superabsorbent resins,and the C3-substituted sulfates exhibit better water absorption capacity.(3)A superabsorbent polymer prepared using aminopyridine chitosan as a skeleton,which is a chitosan derivative with excellent antibacterial properties.While ensuring good water absorption and water retention properties of the superabsorbent polymer,a novel superabsorbent polymer having antibacterial properties was prepared by the introduction of the antibacterial group.Bacteriostatic experiments showed that the superabsorbent polymer has good antibacterial activity against Escherichia coli and Staphylococcus aureus.(4)Three kinds of superabsorbent polymer products were prepared by solution polymerization using chitosan derivatives with different carboxymethylation sites as the backbone.FT-IR,XRD,TG-DSC and other means were used to characterize the products,which confirmed the successful preparation of superabsorbent polymer.The apparent morphology of the polymer was observed by scanning electron microscopy.The superabsorbent polymer product prepared by the polysaccharide has a larger diameter and more developed pore structure on the surface,and the developed porous structure has an effect of improving the water absorption capacity and the water absorption rate of the resin,and the maximum water absorption ratio can reach at 628 g/g.In this paper,different chitosan derivatives were used as the framework to study the role of chitosan derivatization in the preparation of superabsorbent polymers.The disadvantages of insufficient mechanical strength,poor salt tolerance and lack of antibacterial activity of the chitosan-based superabsorbent polymer have been improved by different derivatives.Good performance can broaden the application space of chitosan-based superabsorbent polymer,and this work also provides a basis for directional design of new superabsorbent polymers with specific properties.