TY - JOUR
T1 - Synthesis and thermal characterization of xylan-graft-polyacrylonitrile
AU - Ünlü, Cüneyt H.
AU - Öztekin, N. Simge
AU - Atici, Oya Galioǧlu
PY - 2012/10/1
Y1 - 2012/10/1
N2 - In this study emulsion polymerization of acrylonitrile using xylan from agricultural waste material (corn cob) and cerium ammonium nitrate was investigated in terms of catalyst acid. Stock ceric solutions were prepared using either nitric or perchloric acid as catalyst. Optimum conditions were determined using different parameters such as reaction time, temperature, and component concentrations. Nitric acid catalyzed reactions resulted in maximum conversion ratio (96) at 50 °C, 1 h where ceric ion, acrylonitrile, xylan, and catalyst concentrations were 21.7 mmol l-1, 0.5 mol l -1, 0.2 (w/v), and 0.1 mol l-1, respectively. However, 83 conversion was obtained with perchloric acid catalysis at 27 °C, 1 h where concentrations were 5.4 mmol l-1, 0.8 mol l-1, 0.5 (w/v), and 0.2 mol l-1, respectively. Copolymer synthesis using perchloric acid was realized at milder conditions than using nitric acid. Thermal analyses of obtained polymers were conducted to characterize copolymers. Results showed that calculated activation energy, maximum degradation temperature, and heat of thermal decomposition changed relying mainly on molecular weight.
AB - In this study emulsion polymerization of acrylonitrile using xylan from agricultural waste material (corn cob) and cerium ammonium nitrate was investigated in terms of catalyst acid. Stock ceric solutions were prepared using either nitric or perchloric acid as catalyst. Optimum conditions were determined using different parameters such as reaction time, temperature, and component concentrations. Nitric acid catalyzed reactions resulted in maximum conversion ratio (96) at 50 °C, 1 h where ceric ion, acrylonitrile, xylan, and catalyst concentrations were 21.7 mmol l-1, 0.5 mol l -1, 0.2 (w/v), and 0.1 mol l-1, respectively. However, 83 conversion was obtained with perchloric acid catalysis at 27 °C, 1 h where concentrations were 5.4 mmol l-1, 0.8 mol l-1, 0.5 (w/v), and 0.2 mol l-1, respectively. Copolymer synthesis using perchloric acid was realized at milder conditions than using nitric acid. Thermal analyses of obtained polymers were conducted to characterize copolymers. Results showed that calculated activation energy, maximum degradation temperature, and heat of thermal decomposition changed relying mainly on molecular weight.
KW - Ceric ammonium nitrate
KW - Graft copolymer
KW - Polyacrylonitrile
KW - Thermal characterization
KW - Xylan
UR - http://www.scopus.com/inward/record.url?scp=84864451867&partnerID=8YFLogxK
U2 - 10.1016/j.carbpol.2012.06.053
DO - 10.1016/j.carbpol.2012.06.053
M3 - Article
C2 - 22840048
AN - SCOPUS:84864451867
SN - 0144-8617
VL - 90
SP - 1120
EP - 1126
JO - Carbohydrate Polymers
JF - Carbohydrate Polymers
IS - 2
ER -