平成30年12月博士課程修了予定者論文発表会　原子核工学専攻

平成30年10月10日（水）　会場： 先導原子力研究所　 北2号館6F会議室

開始時刻／ 終了時刻	発表者氏名	指導教員	論　　文　　題　　目
10：15 12：15	Yokachukususe Nutthon IGP-(A)	塚原剛彦 小原　徹	Evaluation of Physicochemical Properties of Thermoresponsive Polymer Brushes and Its Application to Mutual Separation of Lanthanides
Development of environmentally-friendly separation method of minor actinides and lanthanides has become of crucial issues in an advanced nuclear fuel cycle. In this study, thermoresponsive copolymer brushes, poly(N-isopropylacrylamide) with 1-Vinyl-1,2,4-triazole [poly(NIPAAm-co-TZ)], grafted onto porous silica (P-SiO2) were synthesized, and mutual separation of trivalent lanthanide ions (Ln3+) was successfully demonstrated by only temperature swing. The copolymer brushes enabled adsorption/desorption Ln3+ depending on differences in interactions between individual Ln3+ and TZ moiety and in the hydration states.  Changes of microscopic structures of the copolymer brushes could be elucidated by small-angle neutrons scattering (SANS) in terms of the attitude of scattering and radius gyration at various temperatures. Molecular dynamics of water confined in the copolymer brushes were examined by temperature-dependent low-field pulsed 1H-NMR in term of relaxation time. By combination of SANS and NMR results, adsorption/desorption mechanism of Ln3+ in the nano-confinement geometries was revealed.