Alternative TitleN-イソプロピルアクリルアミドに基づく温度応答性ブロック共重合体の調製と化学スイッチングデバイスへの応用
Note (General)Poly(N-isopropylacrylamide) (PNIPAAm) is an excellent thermal responsive polymer with a lower critical solution temperature (LCST) in water of 32 ℃. The properties of PNIPAAm can be altered by changing the temperature around LCST. When the temperature is below the LCST, the intermolecular hydrogen bonds between the PNIPAAm chains and the water molecules contribute to an extended brush structure displaying hydrophilicity. When the temperature is above the LCST, the intramolecular hydrogen bonds in the PNIPAAm chains could lead to a compact and collapsed conformation with hydrophobic property. This dissertation focuses on the preparation of NIPAAm based block copolymers and their application in chemical switching device. The thermally responsive property and applications of PNIPAAm are introduced in Chapter 1. In Chapter 2, the copolymer, poly(N-isopropylacrylamide-co-hexafluoroisopropyl acrylate) (poly(NIPAAm-co-HFIPA)), was initially synthesized via surface-initiated atom transfer radical polymerization (ATRP) method. The HFIPA added to enhance the hydrophobicity of the polymer. And the water contact angle (CA) was measured to evaluate the surface characteristics. The results indicated that the copolymer showed hydrophilic/hydrophobic transition with temperature across LCST. The copolymer has great potential for use in various important applications, including water controllable transportation, molecular separation, and so on. In Chapter 3, a smart and reversible chemo-mechanical switch was developed for controllable water transportation. The smart switch was constructed by integrating poly(NIPAAm-co-HFIPA) on a capillary plate. With the temperature changing around LCST, the designed chemo-mechanical switch exhibited excellent “ON–OFF” behavior for water transportation. Meanwhile, the sequences of copolymer affected on properties of switching have investigated. The excellent controllability over aqueous solution transportation indicates that it has great potential for use in various important applications, including intelligent microfluidic switching, water/oil separation, controllable drug release, and so on. In Chapter 4, the copolymer, poly(N-isopropylacrylamide-co-methacrylic acid) (poly(NIPAAm-co-MAA)), was synthesized via free radical initiated precipitation polymerization. To match the human physiological temperature, the MAA was added to raise the LCST of the copolymer. The results showed the copolymer with the NIPAAm:MAA molar ratio of 100:10 have a satisfactory LCST of 37.5 ℃. Meanwhile, the period for the copolymer conformation change was only 8 min. The synthesized copolymer has great potential for use in human drug delivery system. In Chapter 5, a straightforward approach for the preparation of monodisperse porous polymer particles by inkjet technology was developed. The merit of the inkjet-based method for polymer particles production was demonstrated by using sodium poly(styrenesulfonate) (NaPSS) solution as a typical example. In which, NaPSS solution can form monodisperse porous polymer particles in a single step. Subsequently, the cross-linked 1,6-hexanediol diacrylate (HDDA) particles with hollow core-porous shell structure were produced by the combination of ink-jetting and UV polymerization approach. The chemical and physical properties stability of HDDA particles have high potential for used as drug carriers. In Chapter 6, a thermo-responsive drug delivery system was fabricated by grafting the copolymer poly(NIPAAm-co-MAA) onto the surface of HDDA particle. The drug molecules can be enclosed when the temperature below 37 ℃, where the pore channels were closed by the swelling copolymer. Whereas as the temperature increasing, the copolymers become collapsed, and the drug could released from the opening pore channels. The drug controlled release behavior has been investigated. In Chapter 7, the principal findings and results of this thesis are briefly summarized.
首都大学東京, 2015-09-30, 博士(理学), 甲第584号
Collection (particular)国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
Date Accepted (W3CDTF)2017-03-02T13:20:07+09:00
Data Provider (Database)国立国会図書館 : 国立国会図書館デジタルコレクション