|
Authors
|
Voigt, I. ; Simon, ; Estel, K. ; Spange, St.
|
|
Title
|
Structure and Surface Polarity of Poly(vinylformamide-co-vinylamine) (PVFA-co-PVAm)/Silica Hybrid Materials
|
|
Date
|
05.06.2001
|
|
Number
|
9439
|
|
Abstract
|
Structure and surface polarity properties of poly(vinylformamide-<I>co</I>-vinylamine) (PVFA-<I>co</I>-PVAm)/silica hybrid materials are investigated by means of electrokinetic measurements, atomic force microscopy(AFM), and solvatochromic probes. AFM measurements show the complete covering of the silica surfacewith the PVFA-<I>co</I>-PVAm layer, which has a thickness between 0.5 and 2 nm depending on the contentof the poly(vinylamine) (PVAm) component of the copolymer. The <I>E</I><SUB>T</SUB>(30) surface polarity parameters ofPVFA-<I>co</I>-PVAm/silica hybrid particles were investigated by two differently substituted Reichardt's dyes,2,6-diphenyl-4-(2,4,6-triphenyl-<I>N</I>-pyridino)phenolate (<B>1</B>) and its lipophilic derivative 2,6-di(4-<I>tert</I>-butylphenyl)-4-[tris-2,4,6-(4-<I>tert</I>-butylphenyl-<I>N</I>-pyridino)]phenolate (<B>2</B>). Adsorption of the basic polymer PVFA-<I>co</I>-PVAm on silica significantly decreases the hydrogen bond donating capacity of the former silica surface,and therefore the <I>E</I><SUB>T</SUB>(30) surface polarity decreases linearly with increasing the content of the PVAmcomponent of the copolymer. Furthermore, it is shown that <I>E</I><SUB>T</SUB>(30) surface polarity values of the PVAm-<I>co</I>-PVFA/silica particles measured with <B>2</B> in toluene correlate with the isoelectric points determined bymeans of electrokinetic measurements in diluted aqueous electrolyte solutions.
|
|
Publisher
|
Langmuir
|
|
Wikidata
|
|
|
Citation
|
Langmuir 17 (2001) 3080-3086
|
|
DOI
|
https://doi.org/10.1021/la001366s
|
|
Tags
|
|
