The Effects of Different Components in Pd2+/Rare Earth Catalytic System on Synthesis of a Polyketone

The linear copolymer of styrene (ST) and carbon monoxide (CO) was prepared in the presence of palladium acetate, cupric p-toluenesulphonate and rare earth acetate RE(OAc)3 (RE= Pr, Nd, Eu, Dy, Ho) multiplex catalyst system. The structure of products was characterized by 13C NMR and FTIR. It is found that the catalytic activity of the system increases with the increasing of atomic number and decreasing of the ionic radius from praseodymium to holmium. The best catalytic effect was obtained when the molar ratio of Pd2+: Ho3+: Cu2+ was 1:4:4, and the catalytic activity was 1194 g/(gPd·h). The effects of the different components including methanol, 2,2-bipyridyl, p-toluenesulphonic acid, and p-benzoquinone on the copolymerization were also studied in detail. To evaluate the influence of different components on the catalyst system, the principal component analysis method was employed. The experiments and data analysis performed have shown that three principal components are significant for evaluation of total variability of the catalytic system.