The promotion effects of some triflates in the copolymerization of styrene and CO were studied.It was found that PdCl2showed good catalytic activity in the exist of some triflates and among them Cu(OTf)2showed the best promotion effects.Under the reaction conditions: 1×10-4mol PdCl2,5×10-4mol bipy,2×10-4mol Cu(OTf)2,3×10-3mol BQ,4ml methanol,10ml styrene,T=333K,P=3.0MPa,the catalytic activity of PdCl2/ bipy / M(OTf)nis 18,000gPK/molPd.h.The effects of the amount of Cu(OTf)2and trific acid on PdCl2catalytic activity were also studied.Mechanism of copolymerization catalyzed by this catalytic system wasdiscussed.
The adsorbed state of propylene oxide on MgO,ZnO and Al2O3were studied by IR spectroscopy.The IR results of PO adsorbed on MgO showed the appearance of 3 080 cm-1and 1 644 cm-1characteristic adsorption bands,which attribute to alkylene species,and the epoxide ring of propylene oxide was preferentially opened at O-C(1) bond.PO adsorbed on Al2O3showed the appearance of 1106cm-1peaks,which attribute to C-O stretching vibration,and the epoxide ring was preferentially opened at O-C(2) bond.The adsorbed species formed on MgO and Al2O3had the stability to some extent.The results of PO adsorbed on ZnO showed no chemical absorption occuring on ZnO suface.