摘要
设计合成了3种[ONSO]型金属铝配合物,通过核磁共振氢谱(1H-NMR)、傅里叶变换红外光谱仪(FT-IR)、紫外可见分光光度计(UV-vis)和液质联用仪(HPLC-MS)对金属铝配合物进行了表征。将其作为催化剂考察在环氧环己烷(CHO)和邻苯二甲酸酐(PA)聚合反应中的催化行为。使用配合物1详细考察了聚合时间、反应温度等条件对聚合反应活性的影响,所得聚合物采用1H-NMR、FT-IR和凝胶渗透色谱(GPC)进行表征。结果显示,所得聚合物聚醚含量为98%,单位时间内每摩尔催化剂转化的单体数(TOF)最高可达2475 h-1,Mw最高可达3. 2×105,相对分子质量分布最低为2. 0,聚合反应动力学研究结果表明,该聚合反应对单体呈一级反应,活化能为13. 91 k J/mol。
Three kinds of aluminum complexes bearing [ONSO]-type ligands were synthesized. They were characterized by1H-NMR,FT-IR,UV-vis and HPLC-MS. The complex was used in the polymerization of cyclohexene oxide and phthalic anhydride as catalysts. The reaction parameters,such as different polymerization temperature,mole ratio and polymerization time were employed in order to study the influences on the polymerization activity. The polymers obtained were characterized by1H-NMR,FT-IR,and GPC. The results show that polyether linkage of obtained polymer is98%,the turnover frequency of epoxide to products( TOF) is highly up to 2475 h-1,weight average molecular weight( Mw) could reach 3. 2 × 105 and polydispersity is around 2. 0. The kinetic behavior of complex 1 was investigated and the results show that the polymerization reaction for monomer is first-order reaction and the activation energy is 13. 91kJ/mol.
引文
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