Effects of coagulation conditions on structure and properties of cellulose-based fibers from aqueous NaOH solvent.
Hydroxyethyl cellulose (HEC) fibers with low degree of substitution were prepared by wet spinning of solutions in 8wt% NaOH solvent, and H2SO4/Na2SO4/ZnSO4solution was chosen as coagulants. The influence of coagulation temperature and H2SO4concentration on structure and mechanical properties of resultant HEC fibers was examined by synchrotron X-ray measurements, scanning electron microscope and tensile tests. The results were analyzed from the perspective of coagulation kinetics by determining coagulation rate and mass transfer rate difference. It is shown that the increase of either coagulation temperature or H2SO4concentration would accelerate the diffusion and coagulation process. The lowest coagulation temperature of 20°C or moderate H2SO4concentration around 10-15wt%, which provided a gentle solidification process, favored the development of regular crystal and oriented structure, uniform and dense inner structure as well as cross sections closer to circular, resulting in HEC fibers with better tensile properties.
Jiangsu Engineering Technology Research Center for Functional Textiles, Jiangnan University, Wuxi, Jiangsu 214122, China. Electronic address: wencong828@jiangnan.edu.cn.
Wencong
W
Wang
College of Textiles, The Key Lab of Textile Science and Technology Ministry of Education, Donghua University, Shanghai 201620, China; Modern Textile Institute, Donghua University, Shanghai 200051, China. Electronic address: fxlee@dhu.edu.cn.
Faxue
F
Li
College of Textiles, The Key Lab of Textile Science and Technology Ministry of Education, Donghua University, Shanghai 201620, China; Modern Textile Institute, Donghua University, Shanghai 200051, China.
Jianyong
J
Yu
Jiangsu Engineering Technology Research Center for Functional Textiles, Jiangnan University, Wuxi, Jiangsu 214122, China.
Jian
J
Zhou
Jiangsu Engineering Technology Research Center for Functional Textiles, Jiangnan University, Wuxi, Jiangsu 214122, China.
Hongbo
H
Wang
Coagulation kinetics; Coagulation temperature; H(2)SO(4) concentration; Hydroxyethyl cellulose (HEC) fibers; Structural characteristics; Tensile properties