Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Rheology control by modulating hydrophobic and inclusive associations of side-groups in poly (acrylic acid)
Author: Wang, J.
Li, L.
Ke, H.
Liu, P.
Zheng, L.
Guo, X.
Lincoln, S.
Citation: Asia Pacific Journal of Chemical Engineering, 2009; 4(5 Sp Iss):537-543
Publisher: John Wiley & Sons, Inc.
Issue Date: 2009
ISSN: 1932-2143
Statement of
Jie Wang, Li Li, Hailan Ke, Peng Liu, Li Zheng, Xuhong Guo and Stephen F. Lincoln
Abstract: In this article we demonstrated that the viscosities of modified poly (acrylic acid) (PAA) solutions were tunable by modulating the hydrophobic and inclusion association between alkyl groups and β-cyclodextrin (β-CD) groups grafted to PAA. The viscosity can be controlled by changing the host-guest molar ratio, alkyl chain length, polymer concentration, salt concentration, pH value, temperature, or addition of native β-CD. A viscosity maximum for inclusive polymer networks constructed by mixing hydrophobically modified PAA (HMPAA) and β-CD-modified PAA (β-CDPAA) appeared at the alkyl : β-CD molar ratio of 1 : 1, which implies the inclusion association between HM and β-CD grafts is binary. Longer side chain length or higher polymer concentration led to higher viscosity for aqueous HMPAA solution with only hydrophobic association or its mixture with β-CDPAA with inclusion association. Monotonically increasing the ionic strength or pH value resulted in a viscosity maximum due to the competition between electrostatic repulsion and hydrophobic or inclusive association. The hydrophobic interactions of alkyl groups could be masked by native β-CD, and the networks of HMPAA and β-CDPAA mixture deconstructed upon addition of native β-CD molecules. The storage modulus and loss modulus of hydrophobic HMPAA and inclusive HMPAA + β-CDPAA solutions obey time-temperature superposition. The horizontal and vertical temperature shift factors obeyed a simple-exponential Arrhenius relationship, where the activation energies for hydrophobic association system were found to be 3.4 and -12.1 kJ/mol, and for inclusive association system 53.9 and -2.9 kJ/mol, respectively. © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Keywords: cyclodextrin
hydrophobic interaction
inclusion association
Description: Copyright © 2010 Curtin University of Technology and John Wiley & Sons Ltd.
DOI: 10.1002/apj.279
Appears in Collections:Aurora harvest
Chemistry publications
Environment Institute publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.