Yeonju Park1, Minkyoung Kim2, Hae-Jin Chung2, Ah-Hyun Woo2, Isao Noda3, Young-Mee Jung1,2. 1. Kangwon Radiation Convergence Research Support Center, Kangwon National University, Chuncheon 24341, Korea. 2. Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon 24341, Korea. 3. Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA.
Abstract
The temperature and mechanism of phase transition of poly(N-isopropylacrylamide-co-acrylic acid) [P(NiPAAm-co-AAc)], which is one of the multi-stimuli responsive polymers, were investigated at various pHs using infrared (IR) spectroscopy, two-dimensional (2D) gradient mapping, and two-dimensional correlation spectroscopy (2D-COS). The determined phase transition temperature of P(NiPAAm-co-AAc) at pH 4, 3, and 2 based on 2D gradient mapping and principal component analysis (PCA) showed that it decreases with decreasing pH, because COOH group in AAc changes with variation of pH. The results of 2D-COS analysis indicated that the phase transition mechanism of P(NiPAAm-co-AAc) hydrogel at pH4 is different from that at pH2 due to the effect of COOH group of AAc.
The temperature and mechanism of phase transition of pan class="Chemical">poly(N-isopropylacrylamide-co-acrylic acid) [n>an class="Chemical">P(NiPAAm-co-AAc)], which is one of the multi-stimuli responsive polymers, were investigated at various pHs using infrared (IR) spectroscopy, two-dimensional (2D) gradient mapping, and two-dimensional correlation spectroscopy (2D-COS). The determined phase transition temperature of P(NiPAAm-co-AAc) at pH 4, 3, and 2 based on 2D gradient mapping and principal component analysis (PCA) showed that it decreases with decreasing pH, because COOH group in AAc changes with variation of pH. The results of 2D-COS analysis indicated that the phase transition mechanism of P(NiPAAm-co-AAc) hydrogel at pH4 is different from that at pH2 due to the effect of COOH group of AAc.
Authors: Rimesh Augustine; Dae-Kyoung Kim; Nagendra Kalva; Kuen Hee Eom; Jae Ho Kim; Il Kim Journal: J Mater Chem B Date: 2020-06-10 Impact factor: 6.331
Authors: Maksim Kunitski; Nicolas Eicke; Pia Huber; Jonas Köhler; Stefan Zeller; Jörg Voigtsberger; Nikolai Schlott; Kevin Henrichs; Hendrik Sann; Florian Trinter; Lothar Ph H Schmidt; Anton Kalinin; Markus S Schöffler; Till Jahnke; Manfred Lein; Reinhard Dörner Journal: Nat Commun Date: 2019-01-02 Impact factor: 14.919