Macromolecular assembly controlled by inclusion associations of α-, β- or γ-cyclodextrin

POLY 99

Xuhong Guo, guoxuhong@ecust.edu.cn1, Li Li, lili76131@ecust.edu.cn1, Lin Fu, lfu@princeton.edu2, Robert K. Prud'homme, prudhomm@princeton.edu2, and Stephen F. Lincoln3. (1) State-Key Laboratory of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China, (2) Department of Chemical Engineering, Princeton University, Olden Street, Princeton, NJ 08544, (3) Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
Macromolecular assembly driven by inclusion associations between cyclodextrin (CD) and hydrophobe (C18) in hydrophobically modified poly(acrylic acid) (HMPAA) was investigated. Their viscosities in water were tunable by modulating HMPAA hydrophobic interactions and inclusion associations between CD and C18. The α-, β- and γ-CD showed different behaviors in forming inclusion associative complexes. The stoichiometry of inclusion complexes between all CDs and C18 preferred 1-to-1 except the 2 : 1 for α-CD at low polymer concentration (0.5 wt%). Upon addition of surfactant SDS, the depressed hydrophobic associations of HMPAA by α-CD were fully recovered, by β-CD partly, and by γ-CD could not. Due to the large cavity size γ-CD crosslinked polymer chains by accommodating two C18 groups from different PAA chains under high shear, and resulted to a shear-thickening phenomenon. When α- or β-CD attached to PAA, polymer networks were obtained and the inclusion between CD and C18 kept 1-to-1 stoichiometry.
 

General Papers: Functional Materials
6:00 PM-8:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007