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A type of novel [P, O] ligand was synthesized sucessfully.With the type of ligand and Pd(OAc)2 as catalytic system, the polymerization of ethylene and MA, and their copolymerization were investigated systematically.Firstly, [P, O] ligands L1 and L2 were synthesized successfully. The sulfonic acid compounds reacted with lithium hydroxide to form sulfonic acid lithium salt, then reacted with butyl lithium and PPh2Cl to yield L1 and L2. Their structures were characterized by 1H NMR, 31P NMR, IR and MS.Secondly, ethylene and MA homopolymerization were investigated with ligand/Pd(OAc)2 as catalytic system. It showed that L1 has higher activity than L2 when catalyzed homopolymerization of ethylene and MA.When ligand/Pd(OAc)2=1:1, it is suitable to catalyze ethylene polymerization, while ligand/Pd(OAc)2=2:1, it is suitable to cayalyze MA polymerization.The polymers were characterized by DSC, IR and GPC, and it showed that the obtained PMA are amorphous.Thirdly, with ligand/Pd(OAc)2 as catalytic system, the copolymerization of ethylene with MA was investigated in detail.The effect on copolymer were discussed through changing the polymerization temperature, reaction time, solvents, structure of ligands and the ratio of Ligands/Pd(OAc)2. An optimum polymerization conditions was obtained:polymerization temperature:100℃, reaction time:10 h, polymerizaiton pressure:3.0 Mpa, L1/Pd(OAc)2= 1: 1, and 10 mL diglyme. The obtained copolymers were characterized by IR, 1H NMR, DSC and GPC. The content of PE in copolymers are 0.33%-2.54% which was calculated by the method of 1H NMR spectrum integration.Finally, mono-ligated Ni and Pd complexes were tried to prepared by the reaction of [P, O] ligands (L1,L2) with trans-Ni(Ph)(Cl)(PPh3)2 and Pd(OAc)2. But the analysis data have not met the structure of the complexes. The further study is need.Based on our previous research work, a kind ofβ-hydroxy imino ligand(L3) was synthesized successfully. L3 and its imine precursor also were characterized by 1H NMR.
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