淀粉-偶氮苯衍生物接枝共聚物的反相乳液合成及表征

Synthesis and Structural Characterization of Starch-Azo Derivatives Grafting Copolymers in Inverse Emulsion

以Span-80为乳化剂,K2S2O8的碱性溶液引发淀粉与偶氮苯衍生物接枝共聚,考察了反应温度、时间、pH值及乳化剂用量对接枝率和接枝效率的影响。结果表明:在反相乳液中应用价廉无毒的K2S2O8的碱性溶液引发接枝共聚反应,可以达到较高的接枝率和接枝效率。当淀粉用量7.00%,[单体]=0.391 mol/L,[K2S2O8]=8.650 mmol/L,[KOH]=0.178 mol/L,乳化剂用量8.02%,反应时间120 min以及反应温度50℃时接枝率和接枝效率分别达最大值69.88%和94.60%。并应用X-ray衍射、热重分析TGA和差热分析DTA等测试手段对接枝共聚物进行了表征,确证了接枝的发生。

5 water-insoluble graft copolymers were prepared by potato starch and Azo-derivatives in inverse emulsion using Span-80 as emulsifier and K2S2O8 as initiator under basic condition.The effects of the technology parameters such as amount of base,reaction temperature,reaction time and emulsifier on the G% and GE% had been thoroughly investigated and the optimum yield 69.88% of G% was obtained when the concentration of monomer,K2S2O8,KOH and the percentage weight of AGU and emulsifier were used at 0.391,8.650×10-3,0.178 mo1/L,7.00%,8.02% respectively.The optimum reaction period and temperature were 120 min and 50 ℃ respectively.The evidence and structural characterization of the graft copolymers had been researched by means of X-ray diffraction analysis,thermogravimetry analysis（TGA） and differential thermal analysis（DTA）.