TITLE:
Investigation of Chitosan-PVA Composite Films and Their Adsorption Properties
AUTHORS:
Lewis S. Casey, Lee D. Wilson
KEYWORDS:
Chitosan, Polyvinyl Alcohol, Methylene Blue, p-Nitrophenol, Sorption Properties, Composite Films
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.3 No.2,
April
1,
2015
ABSTRACT:
Viscous aqueous solutions of
chitosan and polyvinyl alcohol (PVA) were blended to enhance miscibility and
avoid polymer phase separation. The mixtures were drop-casted and air dried to
yield composite film materials that were characterized by equilibrium water
uptake, physical stability in aqueous solution, and thermal stability.
Chitosan/PVA blends have greater thermal stability, unique morphology, and
reduced solubility in acidic solution, thus extending the useful pH range for
chitosan as a sorbent material. The uptake properties of the films was
investigated using methylene blue (MB) and a p-nitrophenol (PNP) dyes, where it
was found that each single component polymer has greater uptake toward MB than
PNP. A direct relationship between film composition (chitosan:PVA) with
solution pH and the uptake of MB was observed. The results are in agreement
with electrostatic interactions and contributions due to the hydrophobic effect
for such composite materials.