The title copolymer was synthesized by grafting dimethyldiallylammonium chloride onto chitosan with ammonium cerium nitrate as initiator. The effects of reaction temperature, pH and concentration of initiator on produ...The title copolymer was synthesized by grafting dimethyldiallylammonium chloride onto chitosan with ammonium cerium nitrate as initiator. The effects of reaction temperature, pH and concentration of initiator on product yield were examined. The optimum conditions were as follows:90 ℃, concentration of initiator 5×10 -4 mol/L, pH=6. The flocculation experiments on the fermentation wastewater showed that flocculabi- lity of the chitosan graft copolymer was better than the chitosan itself and the flocculation treatment could be carried out at lower dosage and wider pH range.展开更多
A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene"click"reaction and alcohol-isocyanate reactions.Polyisopren...A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene"click"reaction and alcohol-isocyanate reactions.Polyisoprene was synthesized by anionic polymerization using n-butyl lithium as initiator,and the pendant hydroxyl groups were introduced by the thiol-ene reaction of mercaptoethanol with the double bond of 1,2-addition units of PI backbone in the presence of radical initiator azobisisobutyronitrile. Isocyanate end group capped poly(ethylene glycol)(mPEG-NCO) was grafted onto the PI backbone through alcoholisocyanate reaction between the pendant hydroxyl groups and isocyanate group of mPEG-NCO.The structure of the graft copolymer were characterized and confirmed by means of size-exclusion chromatography,~1H NMR and FTIR spectroscopy.展开更多
用硝酸铈铵作引发剂,通过水溶液聚合法制得了玉米淀粉接枝丙烯酸高吸水性树脂。研究了交联剂及引发剂用量、中和度、反应温度以及反应时间等对吸水率的影响。得到的最佳反应条件为:交联剂和引发剂与丙烯酸的摩尔比分别为0.95×10-5...用硝酸铈铵作引发剂,通过水溶液聚合法制得了玉米淀粉接枝丙烯酸高吸水性树脂。研究了交联剂及引发剂用量、中和度、反应温度以及反应时间等对吸水率的影响。得到的最佳反应条件为:交联剂和引发剂与丙烯酸的摩尔比分别为0.95×10-5和4.8×1-0 3,中和度71%,反应温度45℃,反应时间2 h。制得的高吸水树脂在室温下30 m in每克吸蒸馏水和自来水分别约为其自身质量的1000和200倍。展开更多
文摘The title copolymer was synthesized by grafting dimethyldiallylammonium chloride onto chitosan with ammonium cerium nitrate as initiator. The effects of reaction temperature, pH and concentration of initiator on product yield were examined. The optimum conditions were as follows:90 ℃, concentration of initiator 5×10 -4 mol/L, pH=6. The flocculation experiments on the fermentation wastewater showed that flocculabi- lity of the chitosan graft copolymer was better than the chitosan itself and the flocculation treatment could be carried out at lower dosage and wider pH range.
基金supports of the Special Funds for Major Basic Research Projects (NoG2011CB606001)Zhejiang Provincial Top Key Discipline of New Materials and Process Engineering(No 20110926)
文摘A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene"click"reaction and alcohol-isocyanate reactions.Polyisoprene was synthesized by anionic polymerization using n-butyl lithium as initiator,and the pendant hydroxyl groups were introduced by the thiol-ene reaction of mercaptoethanol with the double bond of 1,2-addition units of PI backbone in the presence of radical initiator azobisisobutyronitrile. Isocyanate end group capped poly(ethylene glycol)(mPEG-NCO) was grafted onto the PI backbone through alcoholisocyanate reaction between the pendant hydroxyl groups and isocyanate group of mPEG-NCO.The structure of the graft copolymer were characterized and confirmed by means of size-exclusion chromatography,~1H NMR and FTIR spectroscopy.
文摘用硝酸铈铵作引发剂,通过水溶液聚合法制得了玉米淀粉接枝丙烯酸高吸水性树脂。研究了交联剂及引发剂用量、中和度、反应温度以及反应时间等对吸水率的影响。得到的最佳反应条件为:交联剂和引发剂与丙烯酸的摩尔比分别为0.95×10-5和4.8×1-0 3,中和度71%,反应温度45℃,反应时间2 h。制得的高吸水树脂在室温下30 m in每克吸蒸馏水和自来水分别约为其自身质量的1000和200倍。