The interaction of borate ions with poly(1-(acrylamido)-1-deoxylactitol) (PACL) in aqueous media was investigated. Dilute solution viscometry revealed that low concentrations of Borax (Na2B4O7) increased the intrinsic viscosity of PACL, while higher concentrations reduced it. 11B NMR spectra of borate complexes of methyl Β-D-galactopyranoside (MΒDGP) (taken to model the C-1′ through C-6′ portion of the PACL repeating unit) and the monomer 1-(acrylamido)-1-deoxylactitol (2) showed evidence for α,Β-bidentate, α,Β-dimer, and α,γ-bidentate borate complexes. The 11B NMR spectrum of PACL-borate showed α,Β-bidentate and α,Β-dimer only. The binding constants for the α,Β-bidentate and α,Β-dimer complexes were determined for MΒDGP and 2 by integration of the 11B NMR signals. 13C NMR was used to identify the putative sites of complexation on PACL by comparing the spectra of borate complexes of MΒDGP and 2 with PACL-borate. Complexation was found to occur predominantly at the C-6′, C-4′, and C-3′ positions.
|Original language||English (US)|
|Number of pages||7|
|State||Published - Jul 14 1998|
ASJC Scopus subject areas
- Materials Chemistry