Preparation and characterization of hemicellulosic derivatives containing carbamoylethyl and carboxyethyl groups.
A series of novel water-soluble hemicellulosic derivatives, containing carbamoylethyl and carboxyethyl groups, were heterogeneously synthesized from wheat-straw hemicelluloses with acrylamide (AA) under alkaline conditions. The factors such as reaction temperature, reaction time, molar ratio of catalysis to xylose unit in hemicelluloses and molar ratio of acrylamide to xylose unit in hemicelluloses, were investigated. The average degree of substitution (DS) was calculated by (1)H NMR spectroscopy. DS values up to 0.23 in a one-step synthesis of hemicelluloses derivatives were obtained. Under optimum conditions (60°C, NaOH to xylose unit in hemicelluloses molar ratio of 0.8, AA to xylose unit in hemicelluloses molar ratio of 8.0, reaction time of 1h) an expected ratio of carbamoylethyl group to carboxyethyl group of 4.8 in the hemicellulosic derivatives was obtained. The structural features of the hemicellulosic derivatives were characterized by FTIR, NMR spectroscopy, and by elemental analysis. The current work provides a facile method for the synthesis of hemicellulose derivatives with bifunctional groups, which could be used as wet-end additives in the papermaking industry.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510641, China.
Jun-Li
JL
Ren
Feng
F
Peng
Run-Cang
RC
Sun
D002219:Carbamates / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D011134:Polysaccharides / Q000138:chemical synthesis* / Q000737:chemistry*; D012995:Solubility
D002219:Carbamates; D002264:Carboxylic Acids; D011134:Polysaccharides; C007916:hemicellulose