| Keratin, a kind of protein, exists widely in human and animal organs including epidermis, hair, wool, feather, hoof and horn. Keratin is a biodegradable, biocompatible, nontoxic and low-cost polymer, which shows potential of wide application. Therefore keratin is a highly useful material and worth being recovered. However at present a majority of keratin are discarded, such as wool unable to be spun, chicken feather and hair which resulting in waste of the natural resource and pollution of the environment.To recover keratin and protect environment, a proton conducting membrane and a novel slow-release fertilizer from hair and wool is studied in this thesis. The conductivity of the membrane and the release rate of the fertilizer are tested. On the basis of former research, the property of reduced keratin membrane and the effect of oxidation condition on reduced keratin membrane are discussed also.Firstly the conductivity of keratin proton conducting membrane is studied, the effect of oxidation condition of direct oxidation method, oxidation method after swelled, oxidation method after reduced and oxidation method after swelled and reduced on the conductivity is investigated. The experimental result indicates that the conductivity of the membranes change considerately with the oxidation condition usually. Of the four oxidation methods, the conductivity of the keratin membrane prepared by the oxidation method after swelled and reduced is the highest one. The highest conductivity of wool and hair can reach 3.19×10-3S·cm-1and 8.35×10-3S·cm-1 respectively. The effects of moulding conditions on membrane conductivity are also tested. The results show that the moulding pressure, moulding temperature, powder mass, powder scale all have effect on the conductivity. Other properties related with conductivity are also measured. The methanol permeability of keratin membrane can reach under 10-6cm2.S-1 and appropriate preparation condition leads to lower methanol permeability. The mechanical property, H2 permeability, water content and density of the membrane are also determined. All these properties are affected by the moulding condition.Secondly to clearly understand the membrane forming mechanism and membrane properties, mercapto cross linkages of reduced keratin membrane under three oxidation conditions are studied. The results show that stronger oxidation condition results in denser cross-linked structure, which makes lower water adsorption, higher maximal tensile strength and longer elongation at break, less H2 permeability.At last a novel slow-release urea fertilizer with keratin carrier is prepared. Effects of keratin powder on soil and leaching ratio of slow-release fertilizer are tested. The denatured keratin powder is more biodegradable than keratin material. Keratin in degradation improves microbe activity, mineral nitrogen and soil respiration. However the pH of soil can be adjusted and the IEC can be improved. The column eluviation experiments show that the release rate could be controlled by moulding pressure, moulding temperature, oxidation time, urea content and urea scale. The cumulative release rate may be controlled between 22%-62% which is very close to that of Luxecote and SCU the two merchandized slow-release fertilizer.
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