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应用*CO_2淬灭法和IR、UV分析手段跟踪研究了环烷酸钕-三异丁基铝[Nd-(naph)_3-Al(i-Bu)_3]络合催化苯乙炔直接成膜聚合体系中活性络合物的形成和变化,聚合条件对催化活性的影响及聚合反应动力学与机理。稀土络合催化苯乙炔直接成膜聚合是典型的链锁反应,表观聚合速率对单体浓度、活性络合物浓度均为一级关系,表观活化能为13.6kJ/mol,影响聚合活性的本质在于聚合体系中形成了活性与非活性两种络合物。活性络合物是瞬间形成,不断消耗,不断产生活性中心。活性中心在聚合过程中可能发生链自动中止,不断失活。溶剂的给电子能力减弱或助催化剂的烷基化能力增强,都将有利于活性络合物的形成。指出了活性络合物的形成及催化聚合模式。
The direct polymerization of phenylacetylene with Nd-naphthalene-3-Al (i-Bu) _3] complexes catalyzed by CO_2 quenching method and IR, UV analysis was studied. The formation and the change of the active complex in the system, the influence of the polymerization conditions on the catalytic activity and the kinetics and mechanism of the polymerization reaction. The rare-earth complexcatalyzed phenylacetylene film-forming polymerization is a typical chain reaction, the apparent polymerization rate of monomer concentration, active complex concentration are first-class relationship, the apparent activation energy of 13.6kJ / mol, affecting the polymerization activity The nature of the polymerization system is the formation of both active and inactive complexes. The active complex is instantly formed, constantly depleting, and constantly producing active centers. Active centers in the polymerization process may occur chain automatically suspended, constantly inactivated. The weakening of the electron donating ability of the solvent or the enhancement of the alkylation capacity of the cocatalyst will all contribute to the formation of the active complex. The formation of active complexes and the mode of catalytic polymerization are pointed out.