Preparation And Properties Of Protein-based Polymer Materials

Protein,as a kind of biodegradable and renewable natural polymer materials,has gradually been attracted the attention of scientists in the fields of chemistry,biomedicine and materials,and used for the preparation of functional materials and biomedical materials.Keratin is a byproduct of the poultry production and textile industry,which is a class of cysteine-rich fibrous protein,and it is difficult to be directly used by humans and animals because of its special molecular structure.Zein is the main byproduct of com processing and its application in human food is limited because of low nutritional value and water-solubility.In this paper,by choosing 1-ethyl-3-methylimidazolium acetate(EMIMAc)ionic liquid as the solvent,the feather keratin/cellulose and feather keratin/polyacrylonitrile mixed solutions were prepared after dissolving the waste feathers,and their rheological properties were studied,respectively.After blending and regenerating,the structures and properties of the regenerated products were characterized.In addition,a series of porous materials with different morphologies were prepared by using zein as raw material and CaC03 as template,further their loading and release properties for drugs were also studied.Firstly,adopting feather fibers and cellulose as raw materials,a uniform and stable feather keratin/cellulose mixed solution(CFE)was got by dissolving them in 1-ethyl-3-methylimidazole acetate(EMIMAc)ionic liquid,and the feather keratin/cellulose blended film(CF)was prepared successfully by regeneration.The rheological properties of CFE were measured and the structures and properties of CF were characterized by SEM,FT-IR,XRD and TGA.It was noted that CFE mixed solution showed shear thinning behavior.With the addition of feather keratin solution(FKE)and the increasing of temperature,the viscosity of the mixed solution decreased as well as the flowability increased,and the rheological parameters we tested were decreased.The intermolecular interactions were increasing with adding the feather keratin to the cellulose and the compactness of blended films could be improved by adding proper feather keratin.Therefore,keratin could improve the compactness and thermal stability of cellulose film material effectively.Secondly,with feather fibers and polyacrylonitrile as raw materials,feather keratin/polyacrylonitrile mixed solution(PFE)was got by dissolving them in EMIMAc ionic liquid,and keratin/polyacrylonitrile blended films(PF)and fibres(PFF)were successfully prepared by regeneration.The rheological properties of PFE were measured and the structures and properties of PF were characterized by means of SEM,FT-IR,XRD and TGA.It was found that PFE mixed solution showed shear thinning behavior.With the addition of feather keratin solution(FKE)and the increasing of temperature,the viscosity of the mixed solution decreased and the flowability increased,and the rheological parameters we tested were changed.The proper addition of keratin,which could disperse evenly in polyacrylonitrile,could increase the compactness of regenerated products.PFF fiber could be produced by dry-jet wet-spinning technology from PFE solution.The prepared PFF fiber was uniform and dense,and had excellent moisture absorption and desorption.Thirdly,porous zein-based micro materials were fabricated through co-precipitation method by using zein as raw material and calcium carbonate as template,of which structures and morphologies were characterized by FT-IR,TG and SEM.It was turned out that the structures and thermal stabilities of ZM materials were similar to zein.By adjusting the ratio of protein to template,the porous materials with different morphology were obtained.The drug loading and release properties of ZM were studied via using curcumin as alcoholic small molecule drug and bovine serum albumin(BSA)as the macromolecular drug.It was found that ZM porous materials with different morphologies could be used to load different drugs depending on their pore size.The drug loading and encapsulation efficiency of ZM5 with porous multilayer loaded protein were improved significantly.The macromolecules were released slowly from ZM5 and had sustained release behavior in different release media.In conclusion,this paper broadened the application of feather keratin in the film and fiber,improved the inadequacy of cellulose and polyacrylonitrile regeneration products,and further provided a reference for further preparation of new materials.At the same time,the fabrication of zein porous material by the template method not only extended the application range of zein,but also provided a reference for further exploration of efficient,cheap and intelligent drug carrier.