title: Characterization of cationic starch flocculants synthesized by dry process with ball milling activating method.
abstract: The cationic starch flocculants were synthesized by the reaction of maize starch which was activated by a ball-milling treatment with 2,3-epoxypropyl trimethyl ammonium chlorides (ETMAC) using the dry method. The cationic starches were characterized by several approaches including scanning electron microscope (SEM), degree of substitution (DS), infrared spectrum (IR), X-ray diffraction (XRD), flocculating activity, electron spin resonance (ESR), and solid-state nuclear magnetic resonance (NMR). The effect of mechanical activation on starch etherifying modification was investigated. The mechanical activation cracked starch granules and destructed their crystal structures. This resulted in enhancements to the reaction activity and reaction efficiency, which was approved by ESR and solid state NMR. The starch flocculants, synthesized by the reaction of mechanically activated starches at 90°C for 2.5h with ETMAC at molar ratio of 0.40:1.00, showed good flocculation activity. The substitution degree (0.300) and reaction efficiency (75.06%) of starch flocculants synthesized with mechanically activated starches were significantly greater than those of starch flocculants with native starches (P<0.05).
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China.
authors.forename: Yuting
authors.initials: Y
authors.lastname: Su
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China. Electronic address: hydu@mail.hzau.edu.cn.
authors.forename: Hongying
authors.initials: H
authors.lastname: Du
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China.
authors.forename: Yinqiang
authors.initials: Y
authors.lastname: Huo
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China.
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Science, Wuhan430071, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Science, Wuhan430071, PR China.
authors.forename: Liying
authors.initials: L
authors.lastname: Wang
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China. Electronic address: zsmjx@mail.hzau.edu.cn.
authors.forename: Siming
authors.initials: S
authors.lastname: Zhao
authors.affiliation: College of Food Science and Technology and MOE Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 40070, PR China.
authors.forename: Shanbai
authors.initials: S
authors.lastname: Xiong
mesh_terms: D018360:Crystallography, X-Ray; D005427:Flocculation; D055595:Mechanical Phenomena; D013213:Starch / Q000737:chemistry*; D013499:Surface Properties; D003313:Zea mays / Q000737:chemistry
chemical_list: D013213:Starch
keywords: Cationic starch flocculants; Dry process; Solid state (13)C CP/MAS NMR