钯络合物催化CO/St共聚合动力学

采用以醋酸钯为催化剂母体组成的催化体系 ,催化CO/St(苯乙烯 )的共聚合 .动力学研究表明 ,共聚合经历了短暂的过渡期 ,其间形成了真正的活性中心 .配体结构和用量的变化将影响过渡期内所生成的活性中心的结构及其在催化循环中的活性和寿命

COPOLYMERIZATION KINETICS OF CARBON MONOXIDE/STYRENE CATALYZED BY PALLADIUM

The copolymer of carbon monoxide with styrene is of great interest, because as a monomer, carbon monoxide is particularly plentiful and inexpensive, the presence of the carbonyl groups in the backbone makes the copolymer photodegradable and the copolymer can be chemically modified to become excellent starting materials for other classes of functional polymers. Copolymerization of carbon monoxide/styrene was catalyzed by a catalytic system comprising palladium acetate as precursor. Kinetic study showed that copolymerization underwent a short transition period, in which the real active species were produced. The activity and life of the catalytic system are influenced by a number factors, such as the structure of ligands and their amounts. The mechanism of initiation and the catalytic cycle for the copolymerization were studied. Additionally, through parallel experiments, we concluded that different ligands and their amounts influenced the coordinating structure of the species as well as their catalytic activity and life.