|
Title
Benzylated hemicellulosic polymers from Triploid populous: Characterization of physicochemical structural features and thermal stability
Authors
H. T. WANG M. F. LI J. Y. YIN D. SHE Z. C. GENG X. M. ZHANG and R. C. SUN
Received
October 20, 2012
Published
Volume 47 Issue 9-10 October-December
Keywords
Triploid populous, hemicelluloses, benzylation, thermal properties, FTIR spectroscopy, NMR
Abstract
Chemical modification is one of the most important strategies to obtain novel biomaterials from the abundant
biomacromolecules and to tailor the properties of biopolymers as desired macromolecules for specific application. In
this study, a novel functional biopolymer was synthesized from Triploid populous hemicelluloses with benzyl chloride
in dimethyl sulfoxide (DMSO) using NaOH as catalyst. Biopolymers with degrees of substitution (DS) between 0.08
and 0.34 were obtained by varying reaction temperature, reaction time, and the molar ratio of benzyl chloride to
anhydroxylose unit in hemicelluloses. The chemical structure of benzylated hemicelluloses (BH) was characterized by
FT-IR and 13C NMR spectroscopies. The results showed that the Mw and Mn of BH were lower than those of the native
hemicelluloses. The BH with a low DS had less thermal stability than the native hemicelluloses, whereas the BH with a
high DS had higher thermal stability than the native hemicelluloses. Moreover, BH showed porous surface with small
irregular slices, as evidenced by scanning electron microscope (SEM), which was ascribed to the disruption of
intermolecular and intramolecular hydrogen bonds. These findings indicated that BH with hydrophobic groups could
open up new opportunities for potential application in thermoplastic industries.
Link
|
