摘要
采用开环聚合法,固体超强酸SO42-/ZrO2-CeO2为催化剂,催化丙交酯和聚乙二醇合成PLA-PEG嵌段共聚物,研究了聚乙二醇(PEG)分子量、反应时间、温度、催化剂用量等条件对共聚物的影响,并通过红外光谱、Hammett指示剂法及NH3-TPD等方法对固体超强酸的酸性质进行了表征。结果表明,当焙烧温度为650℃时,得到的固体超强酸SO24-/ZrO2-CeO2酸强度与酸量最大,用该催化剂催化合成PLA-PEG嵌段共聚物,当PEG分子量为6 000,反应时间9 h、反应温度170℃,催化剂用量为丙交酯质量分数的1.0%时,得到PLA-PEG共聚物的特性粘数最大,为1.693 g/dL。
The PLA-PEG block polymer catalyzed by solid super acid SO2-4/ZrO2-CeO2 was prepared by opening ring polymerization.The acidic property was measured by IR spectra,Hammett indicator and NH3-TPD techniques.The effects of molecular weight of PEG,reaction time,temperature and catalyst amount on copolymer were studied,and the characteristic group of copolymer was measured by FTIR spectra.The solid super acid SO2-4/ZrO2-CeO2 had the strongest acid strength and maximal acid content roasted at 650 ℃.The optimum reaction conditions were as follows：the amount of catalyst was 1.0% of lactic,the molecular weight of PEG was 6 000,polymerization at 170 ℃ for 9 h.The intrinsic viscosity reached 1.693g/dL.
出处
《应用化工》
CAS
CSCD
2010年第12期1838-1842,共5页
Applied Chemical Industry
基金
江西省科技厅科技支撑计划资助项目(2007ZD01900)
江西省教育厅科研基金资助项目(GJJ09039)
