文献类型：期刊文献

英文题名：Complexation behavior of α-, β-, and γ-cyclodextrin in modulating and constructing polymer networks

作者：Li, Li[1];Guo, Xuhong[1];Fu, Lin[2];Prud'homme, Robert K.[2];Lincoln, Stephen F.[3]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA;[3]Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia

年份：2008

卷号：24

期号：15

起止页码：8290

外文期刊名：LANGMUIR

收录：;EI(收录号：20083411477480);WOS:【SCI-EXPANDED(收录号:WOS:000258034500091)】；

语种：英文

外文关键词：Complex networks - Restoration - Stoichiometry - Hydrophobicity - Sodium dodecyl sulfate - Solutions - Sulfur compounds

摘要：A systematic study of the host-guest complexation by alpha-, beta-, and gamma-cyclodextrin (CD) in either the free state or as substituents of poly(acrylic acid) (PAA) with the hydrophobic n-octadecyl groups, C18, substituted onto PAA (HMPAA) and its effect on polymer aggregation and network formation is reported. Free alpha-CD, beta-CD, and gamma-CD mask hydrophobic associations between the C18 substituent of HMPAA in aqueous solution and form host-guest complexes with a 1: 1 or CD:C18 substituent stoichiometry at 0.5 wt % polymer concentration. For alpha-CD this host-guest stoichiometry changes to 2:1 or 2 alpha-CD:C18 at >= 1 wt % polymer concentrations but not for beta-CD and gamma-CD. Shear-thickening occurs when gamma-CD complexes C18 HMPAA substituents. Upon addition of sodium dodecyl sulfate, SDS (SDS:CD = 1:1), the hydrophobic associations between C18 diminished by alpha-CD masking were fully restored, were only partly restored in the case of beta-CD, and not restored for gamma-CD. When alpha- and beta-CD substituted PAA (alpha-CDPAA and beta-CDPAA) were mixed with HMPAA polymer, networks formed. As for free beta-CD, the beta-CD substituents of beta-CDPAA also formed 1:1 or beta-CD:C18 stoichiometry host-guest complexes with the C18 substituents of HMPAA. The alpha-CD substituents of alpha-CDPAA also formed 1:1 or alpha-CD:C18 stoichiometry host-guest complexes with some indication of the formation of 2:1 or 2 alpha-CD:C18 stoichiometry host-guest complexes at polymer concentrations >= 1 wt %. The polymer networks formed by beta-CDPAA with HMPAA are less viscous than those formed by alpha-CDPAA, for which shear-thickening occurs at polymer concentrations >= 2 wt %. It is evident that the difference in CD annular size and its match with the C18 of HMPAA control the diversity of the interactions of alpha-CD, beta-CD, gamma-CD, alpha-CDPAA, and beta-CDPAA with HMPAA.