Use of chelatable phenols with metallocene- aluminoxane catalyst systems

A process for producing a polyolefin which comprises contacting at least one olefin and optionally a diene in a polymerization vessel under polymerization conditions with a catalyst composition comprising:

• A′) a metal complex having the structure (CpRn)R1(1−y)(CpRm)MY2 wherein,
• M is a metal selected from the group consisting of Ti, Zr, and Hf;
• each (CpRn) and (CpRm)is independently a cyclopentadienyl or R-substituted cyclopentadienyl group bonded to M, wherein R independently each occurrence is selected from the group consisting of alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, alkylaryl, and arylalkyl, said R containing from 1 to 20 carbon atoms, and optionally at least two R moieties on a R-substituted Cp group are joined together to form a ring having 4 to 6 carbon atoms;
• R1 is selected from the group consisting of (i)C1-C4 substituted or unsubstituted alkenyl radicals, (ii) dialkyl or diaryl substituted germanium or silicon radicals, (iii) alkyl or aryl phosphines, and (iv) amino groups, said R1 bridging the (CpRn) and (CpRm)rings;
• each X is independently selected from the group consisting of (i) hydride, (ii) C1-C20 alkyl, (iii) C1-C20 aryl, (iv) C1-C20 alkenyl, (v) C1-C20 alkylaryl, (vi) C1-C20 arylalkyl, (vii) C1-C20 hydrocarboxy, (vii) C1-C20 aminoalkyl, and (ix) halide;
• n and m are each 0, 1,2, 3, 4, or 5;
• y is 0, or 1;
• and
• each Y is independently a phenoxide radical having the formula:
• wherein:
• A and D are the same or different and are selected from the group consisting of:
• —OR′, —NR′2, —PR′2, —CR′2OR′, —CR′2, NR′2, —COR′, —COOR′, —CONR′2, —OCOR′ and —NR′COR′, wherein each R′ is independently selected from the group consisting of alkyl cycloalkyl, alkenyl, cycloalkenyl, aryl, alkylaryl, and arylalkyl, each R′ containing from 1 to 20 carbon atoms;
• R2 is independently selected from the group consisting of alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, alkylaryl, and arylalkyl, each R2 containing from 1 to 20 carbon atoms;
• and optionally at least two R2 moieties are joined together to from a ring having 4 to 6 carbon atoms;
• and
• k is 0, 1, 2, 3;
• and
• B′) an aluminoxane.