TY - JOUR
T1 - Asymmetric swelling and self-assembly of poly(N-isopropyl-acrylamide)-block-poly(ethylene glycol) in water
AU - Motokawa, R.
AU - Morishita, K.
AU - Koizumi, S.
AU - Yoshimoto, E.
AU - Annaka, M.
N1 - Funding Information:
The work was partly supported by a Grant-in-Aid (No. 15340137) from the Ministry of Education, Culture, Sports, Science, and Technology for M.A.
PY - 2006/11/27
Y1 - 2006/11/27
N2 - This investigation focused on the self-assembly of poly(N-isopropylacrylamide)-block-poly(ethylene glycol) (PNIPA-b-PEG) in water. We distinguish four regions in the phase diagram: a transparent sol, opaque sol, opaque gel, and syneresis. Small-angle neutron scattering measurements revealed that microphase separation occurs above 17 {ring operator} C to form disordered micelles, which includes a range of states from (i) asymmetric swelling to (ii) micelle formation with only short-range liquid-like order. This result may be attributed to the action of water, which starts to behave as a selective solvent for PEG blocks; the PEG chains are more swollen with water than are the PNIPA chains.
AB - This investigation focused on the self-assembly of poly(N-isopropylacrylamide)-block-poly(ethylene glycol) (PNIPA-b-PEG) in water. We distinguish four regions in the phase diagram: a transparent sol, opaque sol, opaque gel, and syneresis. Small-angle neutron scattering measurements revealed that microphase separation occurs above 17 {ring operator} C to form disordered micelles, which includes a range of states from (i) asymmetric swelling to (ii) micelle formation with only short-range liquid-like order. This result may be attributed to the action of water, which starts to behave as a selective solvent for PEG blocks; the PEG chains are more swollen with water than are the PNIPA chains.
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U2 - 10.1016/j.physb.2006.06.050
DO - 10.1016/j.physb.2006.06.050
M3 - Article
AN - SCOPUS:33751327326
VL - 385-386 I
SP - 745
EP - 748
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
SN - 0921-4526
ER -