| Water pollution has seriously threatened to people's life and sustainable development of economy. The exploitation of new high-effective flocculants is of great importance to control water pollution. The organic-inorganic composite flocculant, a new type of high-effective flocculants, has become a hot issue and a new important development direction in the study of flocculant because it has not only the merits of organic constituents but also the merits of inorganic ones. In this paper, a series of new type polymeric quarternary ammonium salt and polyferric sulfate composite flocculants (PQAS-PFS) were synthesized, and the related fundamental theory and application properties of PQAS-PFS were studied systematically.A new two-step method for synthesizing dimethyldiallylammonium chloride (DMDAAC) was exploited: the in-process product dimethylallylamine (DMAA) was synthesized in autoclave firstly, and then reacted with equimolar allyl chloride in acetone to synthesize DMDAAC after separated from water phase; the chlorinated dimethylamine was regenerated by concentrating and neutralizing the separated water phase, and was returned to the autoclave to react next time. Compared with the synthesis of DMAA by adding allyl chloride and sodium hydroxide alternately, the yield of DMAA increased 27.1% and the emission of waste liquid decreased 1.12mL/(mL DMAA). Colorless spiculite DMDAAC (m.p. 144.5~146.1C) with high purity is obtained, and its total yield is up to 89.07%. The polymerization kinetic equations of DMDAAC and the copolymerization kinetic equations of DMDAAC with acrylamide (AM) or acrylic acid (AA) initiated by ammonium persulfate (APS) in aqueous solution are obtained by dilatometric method as follows:Rp=kcI0.76cM1.02 (DMDAAC)Rp=kcI0.70CM2.23 (DM-AM, 4 11)RP=kcI0.61cM2.83 (DM-AA, 4 : 1)The corresponding apparent polymerization activation energies are 71.958, 58.221 and 64.312kJ/mol. The monomeric reactivity ratios of DMDAAC with AM are determined to be r DM= 0.49, r am = 5.49, and those of DMDAAC with AA are r Dm = 0.42, raa= 5.11. On the base of polymerization kinetics and monomeric reactivity ratios, poly(DMDAAC) (PDMDAAC) with different intrinsic viscosity, poly (DMDAAC-AM)(P(DM-AM)) and poly (DMDAAC-AA) (P(DM-AA)) with different intrinsic viscosity and different cationic degrees are designed and synthesized.The columnar crystals diethyldiallylammonium chloride (DEDAAC) with higher purity were obtained firstly by two-step method in which the in-process product diethylallylamine (DEAA) was synthesized using diethylamine as reactant and solvent by adding allyl chloride and sodium hydroxide alternately, and DEDAAC was synthesized by adding equimolar DEAA and allyl chloride in acetone. Its melting point is determined to be 199.5-201.0 C, and its total yield is 58.41%. The polymerization kinetic equation of new type DEDAAC and the copolymerization kinetic equations of DEDAAC with AM or AA initiated by APS in aqueous solution are obtained as follows:Rp=kcI0.76CM0.99 (DEDAAC)Rp=kcI0.90cM2.53 (DE-AM, 4:1)RP=kcI0.83cM2.94 (DE-AA, 4 : 1)The corresponding apparent polymerization activation energies are 73.596, 67.061 and 70.070 kJ/mol, and the monomeric reactivity ratios of DEDAAC with AM are r DE = 0.32, r am = 5.27, and those of DEDAAC with AA are r De = 0.30, Y aa = 5.19. The new type of polymeric quarternary ammonium salts PDEDAAC, P(DE-AM) and P(DE-AA) are synthesized initially.It was firstly found that polymers PDMDAAC and PDEDAAC, copolymers P(DM-AM) and P(DE-AM) with cationic degree above 30mol%, amphoteric copolymers P(DM-AA) and P(DE-AA) with cationic degree above 65mol%, poly vinyl pyrrolidone (PVP) and poly(sodium styrenesulfonate) (NaPSS) could compound with PFS well and formed homogeneous phase composite solutions. Six kinds of PQAS-PFS as PDMDAAC-PFS, P(DM-AM)-PFS, P(DM-AA)-PFS, PDEDAAC-PFS, P(DE-AM)-PFS and P(DE-AA)-PFS were synthesized.The viscometer was firstly employed to study motion mode of PQAS molecular chain in PFS, FT-IR, SEM and X-ray diffraction and Fe...
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