【作者】 彭小敏；

【导师】 童张法； 廖丹葵；

【作者基本信息】 广西大学 ， 化学工艺， 2004， 硕士

【摘要】 淀粉资源在我国比较丰富而且价格低廉，它与乙烯基单体的接枝共聚物具有很优异的合成性和天然高聚物的性质，其具有的可塑性可制造多功能薄膜、高吸水性材料和粘合剂等。尤为引人注目的是淀粉的可再生性和生物的可降解性对于减轻循环污染和对不可再生资源的依赖是有益处的。因此对接枝高聚物的考察引起了广泛的注意，这些材料的运用也变得越来越广泛。在淀粉接枝共聚反应中，采用适当的引发剂就显得特别重要。本文对常用的引发剂、引发剂的特征、引发机理以及引发的应用作了详尽的叙述。通过选用过硫酸钾-亚硫酸氢钠、硝酸铈铵等不同引发剂引发木薯淀粉接枝丙烯酸，证明过硫酸钾-亚硫酸氢钠复合引发剂具有一定的应用潜力，其最佳反应条件为：丙烯酸浓度1.2mol／L，中和度为80％，反应温度35℃，反应时间为3.5小时，引发剂的浓度2.8mmol／L。在硝酸铈铵引发剂引发的条件下，最佳的反应条件是：单体浓度为1.2mol／L，引发剂的浓度为3.0mmol／L，反应的温度50℃，反应的时间为3小时，中和度为80％。最后以过硫酸钾-亚硫酸氢钠为引发剂通过正交实验筛选出最佳反应条件：丙烯酸浓度为2mol／L，温度45℃，反应时间为2.5小时，引发剂的浓度2.5mmol／L，中和度为80％。 本文同时研究了采用高锰酸钾、铈盐和过硫酸钾复合引发剂在木广西才学动送一落戈一茫甜接农，乙帮美卑那时艾全成与二麦征薯淀粉与丙烯酞胺接枝反应中的工艺条件，得出了高锰酸钾为引发剂的最佳反应条件:酸度控制在pH值为2，单体:淀粉量比为2:1，引发剂浓度2.0 mmol/L，反应温度50oC，反应时间2小时。采用复合引发剂的最佳反应条件是:pH值为2，引发剂浓度为2.Ommol/L，反应温度50℃，反应时间3小时。通过正交实验确定采用复合引发剂的最佳反应条件:反应体系HNO。浓度为0.lmol/L，引发剂的浓度3.Ommol/L，单体:淀粉量比2:1，反应温度50℃，反应时间2.5小时。最后分别用红外光谱和电镜对淀粉接枝丙烯酸与淀粉接枝丙烯酞胺产物的结构进行了表征。更多还原

【Abstract】 Starch is abundant and cheap in China. Its graft copolymers with vinylmonomers have excellent properties of the synthetic and natural polymers, such as plasticity and film forming functionality,high-water absorbance, flocculence, adhesive effect and etc. In particular, the renew ability of starch and the biodegradability of the copolymers are beneficial to reduce the load of ambient pollution and the dependence on unrenewable resources. A great deal of attention has been focused on the investigation of the graft copolymers,and the utilization of these substances is becoming more wide-spread. It is the most important for Graft Copolymerization of vinylmonomers onto Starch to choose fit initiators. So normal initiators used for graft polymerization of vinyl monomers on starch are reviewed. The characterization, initiating mechanism and the application of initiators are discussed. This paper reported the graft copolymerization of acrylic acid (AA) onto cassava starch by K2S2O8-NaHSO3 initiators. We found that K2S2O8-NaHSO3 has a hopeful future. Results showed that the condition of reaction was the best when the concentration of AA was 1.2mol/L,the temperature was 35C, the time was 3h,the concentration of the initiator was 3mmol/L and the neutral degree was 80%. The graft copolymerization of acrylic acid onto starch with eerie ammonium nitrate as initiator has been studied. The effects of the reactions parameters, including the amount of inititor and monomer, pH, reaction temperature and time were investigated. The effect of the initiation system was the best when the concentration of AA was 1.2mol/L. the temperature was 50C, the time was 3h,the concentration of the initiator was 3mmol/L and the neutral degree was 80%. Graft polymerization of acrylic acid onto cassava starch using potassium per sulfate-sodium bisulfate as initiators was studied. Five reaction conditions of the graft polymerization are concentration of initiators, reaction temperature, concentration, degrade of neutralization of monomer and reaction times are investigated. We choose different levels of every factor, was chosen to form arthogonal test of five factors and four levels. The result showed that the grafting percentage was higher when concentrations of monomer and initiator were at 1.0mol/L and 3.0mmol/L respectively, the temperature of the reaction was 35 C, the reaction time was 3h, and the neutral degrade was 70%.The graft copolymerization of acrylamide (AM) onto starch initiated by potassium permanganate, potassium persulfate (KPS)- eerie ammonium nitrate was studied. The influence of the concentration of acrylamide and potassium persulfate, temperature and polymerization time on graft percentage and grafting efficiency was investigated. The experimental results showed that both the graft percentage and grafting efficiency were high for initiator of potassium permanganate when the proportion of the acrylmide and the starch was 2, theconcentration of the potassium permanganate was 1.5 mmol/L, the temperature of the reaction was 50 C,the reaction time was 3h, pH degree of the reaction was 2.The result initiated by potassium persulfate (KPS)- eerie ammonium nitrate was better when pH degree of the reaction was 2 to 3,the concentration of potassium persulfate (KPS)- eerie ammonium nitrate was 2 mmol/L, the temperature of the reaction was 50 C,the reaction time was 3h. Then we choose different levels of every factor to form arthogonal test of five factors and four levels. The optimum condition for graft copolymerization was obtained by the experiments when the concentration of the nitric acid was 0.3mol/L,the concentration of potassium persulfate(KPS)- eerie ammonium nitrate was 3.0mmol/L,the proportion of the acrylmide and the starch was 2,the temperature of the reaction was 50X2?the reaction time was 2h. At last, we indicated the figurations of two graft copolymerations using infrared spector and electron microscopy.更多还原