TITLE:
Biodegradation of Styrene-Butadiene-Styrene Coploymer via Sugars Attached to the Polymer Chain
AUTHORS:
Rakesh Singh, Rishi Gupta, Mukund G. Adsul, Ramesh C. Kuhad, Digambar V. Gokhale, Anjani J. Varma
KEYWORDS:
Biodegradation; Antimicrobial; SBS; Sugar; Quaternary Nitrogen
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.3 No.2,
June
5,
2013
ABSTRACT:
A synthetic method was developed to chemically attach few molecules of
simple sugars like glucose, mannose, galactose, maltose and xylose
(0.09 - 0.37 wt%) and with quaternary
nitrogen pendants (0.42 - 0.46 atomic%)
along the polybutadiene section of polystyrene-block-polybutadiene-block-polystyrene
(SBS) block copolymer. These functionalized
SBS copolymers were evaluated for biodegradation using the fungal
culture Aspergillus niger NCIM 1025 (ATCC 9642) and bacterial
culture Pseudomonas sp. NCIM 2220, and for antimicrobial properties using
bacteria E. coli DH5α and Bacillus
subtilis and yeasts Pichia stipitis NCIM 3497 and P. stipitis NCIM 3499. It was conclusively demonstrated that these
modified SBS block copolymers were significantly more biodegradable than the
unmodified SBS; the observed weight loss after biodegradation was ~4 - 14-fold
for bacterial and ~7 - 36-fold for fungal cultures
with respect to the sugar content of modified SBS. Preliminary studies on
antimicrobial properties of these biodegradable polymers showed a 4% - 24%
decrease in growth of the microorganisms E. coli and Bacillus subtilis studied.