Study On Preparation And Peoperties Of Feather Protein-based Superabsorbents

In this paper, superabsorbents were synthesized by graft of acrylic acid onmodified feather protein. The influence of reaction conditions on the properties of thesuperabsorbents were studied, anti-salt property, biodegradability and adsorptiveproperty on heavy metal ion were studied as well.Soluble feather protein was prepared by pre-treatment of feather protein powderwith NaHSO₃ then hydrolyzation in solution containing NaOH. The results showedwhen the dosage of NaHSO₃ was 30wt% of the feather protein, the concentration ofthe solution containing NaOH was 0.4wt%, the proportion of the solution and thefeather protein was 15, the reaction continued at 90℃for 2 hours, 65.7% featherprotein could transform into water soluble protein and the molecular weight wasbetween 10000～40000, suitable for graft of acrylic acid. Modified feather proteinswith improved hydrophilicity were synthesized by formaldehyde and NaHSO₃. thehydrogels of the feather protein and modified feather protein were synthesizedseparately with glutaraldehyde being used as crosslinker, the results showed that theabsorbing ability of the hydrogels of the modified feather protein (45.6g/g) wasmore than that of the hydrogels of the feather protein (21.5g/g).Superabsorbents of modified feather protein grafted acrylic acid were synthesizedby polymerization of modified feather protein and acrylic acid in water when N, N'-methylenebisacrylamide (NMBA) being used as crosslinker and K₂S₂O₈-NaHSO₃ beingused as initiator. When the dosage of modified feather protein was 10wt% of acrylicacid, the dosage of NMBA was 0.12wt% of acrylic acid, the dosage of initiator was0.6wt% of acrylic acid, 90% acrylic acid was neutralized by NaOH, and the reactioncontinued at 60℃for 2 hours, the absorbing ability of the superabsorbents was 559.4g/g in case of distilled water, 68.7g/g in case of physiological saline, 85% water inthe superabsorbents was held under the pressure of 0.3MPa, while the absorbingability of the superabsorbents of crosslinked acrylic acid was 56.9g/g in case ofphysiological saline.Superabsorbents of modified feather protein grafted acrylic acid and acrylamidewere synthesized by polymerization of modified feather protein and acrylicacid/acrylamide in water when NMBA was being used as crosslinker and K₂S₂O₈-NaHSO₃ being used as initiator. When the dosage of modified feather proteinwas 10wt% of acrylic acid and acrylamide, the proportion of acrylic acid andacrylamide was 70: 30, the dosage of NMBA was 0.10wt% of acrylic acid andacrylamide, the dosage of initiator was 0.8wt% of acrylic acid and acrylamide, 90%acrylic acid was neutralized by NaOH, and the reaction continued at 60℃for 2 hours,the absorbing ability of the super absorbents was 578.0g/g in case of distilled water,78.6g/g in case of physiological saline, 85% water in the super absorbents was heldunder the pressure of 0.3MPa.Adsorptive property of the superabsorbents on heavy metal ion were studied inthis paper, the results showed that Pb²⁺, Cu²⁺ can be absorbed by the superabsorbents,and the adsorptive capacity was bigger than 2.2mmol/g, 95.7% heavy metal ion canbe absorbed.Superabsorbents with anti-bacteria activity was synthesized by modified featherprotein grafted acrylic acid, acrylamide and long-chain alkyl allyl dimethylammonium chloride (RADM), and the results showed Staphylococcus aureus,Escherichia coli and Candida albicans can be killed or controlled. When the contentof RADM increased, anti-bacteria activity increased.Biodegradability of the superabsorbents based on modified feather protein andacrylic acid/acrylamide was studied by microbe, and the results showed that the superabsorbents could be degrade by Mould fungi, Actinomyces, Bacillus subtilis. Thesuperabsorbents of modified feather protein and acrylic acid had the best degradability,the hydrogel of the superabsorbents was covered by fungus when contact with thesolution containing Mould fungi.The superabsorbents were modified in particle surface while epoxychloropropane and AlCl₃ being used as crosslinker and ethanol being used asdispersing agent, the results showed that the humidity resistance could be improved,and the absorption rate could be improved from 112 s to 54 s.Influence of the superabsorbents based on modified feather protein and acrylicacid/acrylamide on wheat seeding and properties of soil were studied, and the resultsshowed the evaporation rate of soil could be reduced, difference in temperature of soilbetween day and night could be reduced as well. The coming out ratio of wheat is 14times for soil containing the superabsorbents than that of blank.