TY - JOUR
T1 - Effect of macrocycles on the temperature-responsiveness of poly[(methoxy diethylene glycol methacrylate)-graft-PEG]
AU - Kitano, Hiromi
AU - Hirabayashi, Tadashi
AU - Gemmei-Ide, Makoto
AU - Kyogoku, Mayumi
PY - 2004/8/12
Y1 - 2004/8/12
N2 - A homopolymer of 2-(2′-methoxyethoxy)ethyl methacrylate (DM) dissolved in pure water demonstrated an abrupt increase in its turbidity at a critical temperature (LCST). Meanwhile, the LCST for a copolymer of DM and ω-methoxy(oligoethyleneoxy)ethyl methacrylate (PaM) (PDMP aM) significantly increased with increasing content of PaM residue. Furthermore, the addition of macrocycles such as hexasodium calix[6]arenehexasulfonic acid (SCX6), α-cyclodextrin (α-CD) and 2,6-di-O-methyl-β-cyclodextrin (DM-β-CD) changed the LCST. SCX6 raised the LCST significantly, DM-β-CD slightly raised the LCST and α-CD slightly lowered it. These phenomena could be attributed to the formation of an inclusion complex (polypseudorotaxane) at the grafted PEG chain of the copolymer. ROESY, fluorescence measurements and the viscosity behavior of the SCX6-PEG dimethylether (PEG-DME) mixture supported the theory of the complexation of SCX6 with the PEG chain. The apparent association constants (Kapp) of PEG-DME or grafted PEG with SCX6 and α-CD were determined using fluorescence and UV-vis absorption measurements, respectively. The complexation of the SCX 6-polymer conjugate with PDMPaM was also examined by time-evolution measurements of the turbidity. The effect of the structure of guest and host molecules on the LCST for the copolymer was discussed in detail.
AB - A homopolymer of 2-(2′-methoxyethoxy)ethyl methacrylate (DM) dissolved in pure water demonstrated an abrupt increase in its turbidity at a critical temperature (LCST). Meanwhile, the LCST for a copolymer of DM and ω-methoxy(oligoethyleneoxy)ethyl methacrylate (PaM) (PDMP aM) significantly increased with increasing content of PaM residue. Furthermore, the addition of macrocycles such as hexasodium calix[6]arenehexasulfonic acid (SCX6), α-cyclodextrin (α-CD) and 2,6-di-O-methyl-β-cyclodextrin (DM-β-CD) changed the LCST. SCX6 raised the LCST significantly, DM-β-CD slightly raised the LCST and α-CD slightly lowered it. These phenomena could be attributed to the formation of an inclusion complex (polypseudorotaxane) at the grafted PEG chain of the copolymer. ROESY, fluorescence measurements and the viscosity behavior of the SCX6-PEG dimethylether (PEG-DME) mixture supported the theory of the complexation of SCX6 with the PEG chain. The apparent association constants (Kapp) of PEG-DME or grafted PEG with SCX6 and α-CD were determined using fluorescence and UV-vis absorption measurements, respectively. The complexation of the SCX 6-polymer conjugate with PDMPaM was also examined by time-evolution measurements of the turbidity. The effect of the structure of guest and host molecules on the LCST for the copolymer was discussed in detail.
KW - Graft copolymers
KW - Inclusion chemistry
KW - Macrocycles
KW - Stimuli-sensitive polymers
KW - Water-soluble polymers
UR - http://www.scopus.com/inward/record.url?scp=4544314110&partnerID=8YFLogxK
U2 - 10.1002/macp.200400135
DO - 10.1002/macp.200400135
M3 - 学術論文
AN - SCOPUS:4544314110
SN - 1022-1352
VL - 205
SP - 1651
EP - 1659
JO - Macromolecular Chemistry and Physics
JF - Macromolecular Chemistry and Physics
IS - 12
ER -