| A concern for the environment is driving research into environmentally friendly materials as replacements for part of synthetic materials.While much current research focuses on cellulose,we highlight that feather keratin should also be considered.It is renewable,commercially abundant, consistent quality,and has guaranteed supply.In this dissertation,the modification and application of feathers were investigated.1.The generation,configuration,structure and composition of feathers were reviewed.IR, Raman and x-ray diffraction are mainly used to characterize the structure of feathers,and optical microscope and electron microscope are also used.The applications of feathers were discussed. Feathers were firstly used for filled heat insulation materials and used for spin and weave in recent research.Most research focused on the hydrolysis of feather,including acid hydrolysis,base hydrolysis and acid or base hydrolysis in the presence of oxidant or reducer.Superheated water and sub-critical water were also used to hydrolyze feather.Many research focused on the hydrolysis of feather using bio-method currently;however,most of them focused on finding and culturing keratin hydrolyzing enzyme and keratin degrading bacteria.Feather can be used to prepare fiber-reinforced polymer.Feathers are also used to adsorb organic molecules and heavy metal ions.2.The dissolution and regeneration of the waste feather in an ionic liquid of 1-butyl-3-methylimi-dazolium chloride([BMIM]Cl) were demonstrated for preparing feather based particles.The crystallinity of the regenerated feathers(RF) decreases and the content ofβ-sheet is 31.71%,which is clearly lower than the raw feather(47.19%).The surface property of feather changed from hydrophobicity to hydrophilicity after regenerated from[BMIM]Cl as indicated by the change of the water contact angle from 138 to 76°.RF shows an excellent efficiency for removing Cr(Ⅵ) ions in water.The stress and strain of the film made from feather can be significantly improved by adding a small amount of poly(vinyl alcohol)(PVA) as an additive.The hydroxyl groups in the molecule of PVA can form hydrogen bonds with the groups of amino and carboxyl in keratin chains of the feathers.On the contrary,in the case of polyvinyl butyral(PVB) as an additive, most oxygen atoms in PVB molecules are existed as butyral,and the butyl are hydrophobic,while keratin chains of feathers are hydrophilic.Thus,the film of adding PVB shows a poor mechanical property due to the weaker interaction between PVB and keratin chains.This work demonstrated a new application of the ionic liquid for dissolving feather and a renewable application of waste feather.3.Feather was chemically treated by several methods.(1) Feather was treated with a range of concentrations of NaOH aqueous solutions.(2) Feather was cross-linking modified with epichlorohydrin(Epi) in NaOH aqueous solution(EpiF),and(3) Feather was modified with ethylenediamine(EA) in NaOH aqueous solution by cross-linking with Epi(EAEpiF).The structure and properties of chemically treated feather were investigated by FT-IR,XRD,SEM,elemental analysis and water contact angle measurements.When feather is treated in NaOH aqueous solution, the reactions occurred on the surface rather than in the interior of feather,and keratin fragments exfoliate from the feather surface layer by layer,and then dissolve in aqueous solution.Feather treated with NaOH are similar in structure and properties to raw feather,and shows relatively low sorption capacity for removal of Cr(Ⅵ) ions from water,but higher capacity than that of raw feather and the sorption is physical adsorption.NaOH treated feather shows an excellent capacity of removing Cu(Ⅱ) ion from water,however,it is also physical adsorption.EpiF shows excellent capacity for adsorbing low concentrations of Cr(Ⅵ) ions,while low sorption capacity for Cu(Ⅱ) in water.EAEpiF is hydrophilic and shows 90%efficiency for removing Cr(Ⅵ) ions in the concentration ranges 10～80 ppm,the sorption maybe chemisorption;However,EAEpiF shows low sorption capacity of adsorption Cu(Ⅱ) ion.4.Titanium dioxide/feathers composite materials were prepared by using feather as raw materials,Ti(O-nBu)4 as precursor and ethanol as solvent.The influence of the pretreated reagent concentration of NaOH and the Ti(O-nBu)4 concentration on the modification rate of TiO2 had been investigated,and the optimum reaction conditions were obtained.Feather was firstly treated with 0.1 mol·L-1 of NaOH aqueous solution,then reacted with 1.5%of Ti(O-nBu)4 ethanol solution at 78℃for 24 h.The XRD results demonstrated that the TiO2 in composite material was amorphous phase. SEM indicated that the TiO2 in composite material is a nanometer lay.The composite material does not show any photocatalytic activities;the possible reason is that the TiO2 is not in crystallization phase.5.Titanium dioxide/feathers composite material was prepared using sol-gel method.The XRD results demonstrated that the TiO2 in composite material was anatase.The photocatalytic activities of composite were investigated by using Ponceau 4R and Butyl rhodamine B as model pollutes.The results demonstrated that composite material shows excellent capacity of removing Ponceau 4R with 80%efficiency for removing of Ponceau 4R.The composite material shows excellent capacity of adsorbing anionic dye,the uptake of Poncean 4R can reach 0.27 g·g-1,and the sorption is chemisorption.The composite material shows poor capacity for adsorption of Butyl rhodamine B. The composite material can be easily recovered by filtration for the fiber property of feather.6.The structure and property of acid treated feather were investigated by using different prescription of nitric acid,acetic acid and ethanol.Parts of amino group of keratin were changed to cation after treated with nitric acid.Nitric acid treated feather(NF) shows excellent sorption capacity of adsorbing Ponceau 4R,the sorption is chemisorption.However,NF shows low sorption capacity of adsorbing cationic dye Butyl rhodamine B,however the interactions between feather and Butyl rhodamine B are very strong,the sorption is chemisorption.NF shows excellent adsorption capacity of adsorbing anionic Cr(Ⅵ) with a possible strong interaction of electrostatic attraction,and the sorption is chemisorption.NF also can adsorb Cr(Ⅲ) ion with a relatively weak interaction,although it is a cation metal ion,and the sorption is physical adsorption.However,for Cu(Ⅱ),Mn(Ⅱ) and Co(Ⅱ) ions,NF did not show any adsorption.Therefore,NF can be used as a material for selective adsorption of total Cr from wastewater.
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