Abstract：In order to further develop the new composite modified starch and its application in fine chemicals, medicines, heavy metal flocculants and functional materials, the cyanoethyl cassava starch (CECS) was synthesized by using cassava starch (CS) as main raw materials, acrylonitrile as etherifying agent, NaOH and anhydrous Na2SO4 as catalyst. Subsequently, xanthate cyanoethyl cassava starch (XCECS) was synthesized via catalytic esterification reaction with CS2 as esterifying agent and magnesium sulfate as stabilizing agent. Finally, crosslinked acrylic acid/acrylamide grafted xanthates cyanoethyl cassava starch (AA/AM-XCECS) was synthesized through grafting and crosslinking reaction with ammonium persulfate/sodium bisulfite as grafting initiator, acrylic acid (AA) and acrylamide (AM) as mixed grafting monomer, N,N'-Methylenebisacrylamide as cross-linking agent. The effects of reaction conditions on the etherification degree of substitution (DS), sulfur content, grafting rate (G) and grafting efficiency (GE) were investigated. The structures of target product were characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric-differential thermal analysis (TG-DTG) and elemental analysis techniques. The results showed that the etherification degree of substitution of CECS was 0.110 under the conditions of V(AN)?m(CS) 2.0?4.0, mass ratio of catalyst to CS 0.063, reaction temperature at 50 ℃ for 5 h. The sulfur content in XCECS was 5.76% under the conditions of V(CS2)?m(CECS) 2.0?4.0, mass ratio of NaOH to CECS 0.025, mass fraction of magnesium sulfate solution 5.5% and reaction temperature at 30 ℃ for 2.5 h. The grafting rate and grafting efficiency of grafting copolymer (AA/AM-XCECS) reached 70.01% and 89.97% respectively under the conditions of mass ratio of XCECS to monomer 1.0?0.8, mass ratio of XCECS to N,N'-methylene double acrylamide 1.00?0.01, initiator concentration 8% and reaction temperature at 50 ℃ for 2.5 h.
LI Heping,ZHANG Jun,GONG Jun et al. Synthesis and Characterization of Crosslinked Arylic Acid/Acrylamide Grafted Xanthates Cyanoethyl Cassava Starch[J]. 化学反应工程与工艺, 2019, 35(1): 45-54.
