Patent ID: 6921800

Claim:
A polymerization catalyst obtained by a process that comprises contacting (A) a modified aluminum oxy compound obtained by a process that comprises reacting: an aluminum oxy compound(a) having a ratio of an intensity at 30 ppm(H2) to an intensity at 10 ppm(H1) [H2/H1] in an 27 Al-solid NMR spectrum of less than 0.35, water(b), and a compound(c) having a hydroxy group selected from the group consisting of tertiary alcohols and alcohols substituted with a halogen atom, the alcohols substituted with a halogen being selected from the group consisting of alcohols indicated by the formula CR 1 R 2 R 3 —OH (wherein each of R 1 , R 2 and R 3 independently represents a hydrogen atom or hydrocarbon group having 1 to 20 carbon atoms, which is optionally substituted with a halogen atom and they may be mutually the same or different), halogenated phenol compounds and silanol compounds, wherein the modified aluminum oxy compound (A) has a ratio of an intensity at 30 ppm(M2) to an intensity at 10 ppm(M1)[M2/M1] in an 27 Al-solid NMR spectrum of 0.60 or more, the molar ratio[(a)/(b)] of aluminum oxy compound(a) to water(b) is 1/3 to 1/0.01, and the molar ratio [(a)/(c)] of the aluminum oxy compound(a) to the compound(c) is 1/3 to 1/0.01 with (B) a transition metal compound.