Aluminum complexes for olefin polymerization

#The present invention relates to novel phosphinimine aluminum complexes containing additional heteroatoms selected from the group consisting of oxygen, nitrogen and sulfur.

#Over the last fifteen years or so there has been an increasing interest in complexes other than the Ziegler-Natta complexes which have the potential to polymerize olefins. The work of EXXON and Dow have lead to the commercialization of metallocene and constrained geometry catalysts which produce polymers tending to have a single active catalyst site. This type of research has lead to more complex ligand structures such as those of Brookhart which also show activity as polymerization catalysts. These systems are used with transition metals as the active catalyst center. There is a desire to find new species which may be capable of olefin polymerization with metals other than the transition metals.

#There was a poster presentation by Christopher M. Ong and Professor Douglas W. Stephan of the University of Windsor at the summer meeting of the Chemical Institute of Canada in Toronto which disclosed aluminum phosphinimine complexes. The complex disclosed is a mono aluminum complex having phenyl substituents on the phosphorus atom and trimethyl silyl substituents on the nitrogen atom. The presentation does not disclose the dimer (i.e. carbene complex) of the present invention.

#[(AlMe2)2{(Me3SiN═PPh2)2C═C(O)N(Ad)}] Activated by [CPh3][B(C6F5)4] for Ethylene Homopolymerization

#Toluene (216 mL) was transferred into the reactor with 0.05 mL of PMAO-IP 1 mmol/L) as scavenger. The solution was heated to 50° C. and saturated with 300 psig of ethylene. [(AlMe2)2{(Me3SiN═PPh2)2C═C(O)N(Ad)}] (64.8 umol, 54.96 mg) was dissolved in toluene and injected into the reactor. At the same time, [CPh3][B(C6F5)4] (136.08 umol, 125.52 mg) was dissolved in toluene (12.2 mL) and injected into the reactor. A slight (2-3° C.) temperature rise was observed and the polymerization reaction was terminated by adding 5 mL of MeOH after 30 minutes. The polymer was dried. Yield=1.6 g. Activity=49.2 gPE/mmolcat*hr. M.P.=133.4° C.

#[(AlMe2)2(Me3SiN═PPh2)2C═C(O)N(Ad)}] Activated by PMAO-IP for Ethylene Homopolymerization