Preparation And Application Of NFC/PVA Hydrogel

Natural cellulose has a low price for its rich sources.As raw material,nanofibrillated cellulose(NFC)can be obtained through a chemical pretreatment of TEMPO oxidation combined with a mechanical method of high-pressure homogenization.On the one hand,natural cellulose has good biocompatibility.Without changing the physical properties of cellulose,it is more conducive to cell adhesion and cell growth for the staggered mesh structure of NFC.At the same time,NFC is always used as enhanced biological polymer phase because of its prominent aspect ratio.In addition,because the hydroxyl of the C6 in cellulose is oxidized into carboxyl group during the process of chemical oxidation method,NFC with carboxyl group can be used as adsorbent to study the adsorption of heavy metal ions.Hydrogel,with water as the dispersion medium and mostly with a three-dimensional network structure,maintains a certain shape and high suction.Poly(vinyl alcohol)(PVA)is one of the most commonly used hydrogel carriers,but the single PVA hydrogel is often affected by its inherent defects,such as mechanical strength,flexibility and so on.In summary,NFC was used as enhanced biological polymer phase and fibrillated with PVA in this paper.Firstly,NFC/PVA hydrogel was prepared through physical crosslinking method by freeze-thaw.Considering swelling,tensile properties,bursting pressure and cell compatibility test,the feasibility of NFC/PVA hydrogel used as small diameter artificial blood vessels in tissue engineering scaffolds was evaluated.Meanwhile,NFC/PVA hydrogel was also prepared through chemical crosslinking method by using glutaraldehyde(GA)as crosslinking agent,and characterizated through FTIR,SEM,TG,moisture content and so on.Then,different preparation method of hydrogels,content ratio of NFC/PVA hydrogel,crosslinking degree,pH of solution,adsorption time and other factors taken into consideration,we could observe the changes of the adsorption of heavy metal ions on the NFC/PVA hydrogel.Obviously,with the addition of NFC,the feasibility of NFC/PVA hydrogel used as artificial blood vessels in tissue engineering scaffolds was improved,and the adsorption of heavy metal ions was incresed efficiently.In other words,we found a new value-added application way for natural cellulose.