Process for controlling the MWD of a broad or bimodal resin in a single reactor

A process for polymerizing olefins of 2 to 10 carbon atoms, the process comprising:

• feeding olefin(s) of 2 to 10 carbon atoms to a reactor, under olefin polymerization conditions;
• contacting the feed with:
• catalyst (A) which comprises a supported catalyst of two different sources of transition metal, wherein one of said two different sources of transition metal provides, under said polymerization conditions, a polymerization product of relatively high molecular weight, and wherein a second of said two different sources of transition metal provides, under said polymerization conditions, a polymerization product of lower molecular weight relative to said product of relatively high molecular weight, to provide a resin having two different molecular weight distribution fractions, wherein one of said two different sources of transition metal comprises a metallocene compound of a metal selected from the group consisting of zirconium, hafnium and titanium;
• and
• catalyst (B) which comprises a support matrix and, supported thereon, one of said two different sources of transition metal which is effective to increase one fraction of said two different molecular weight distribution fractions;
• wherein catalyst (A) and catalyst (B) are fed to the reactor as a
• mixture;
• and
• recovering the resin from the reactor.