incorp m m sub n sup b m sub w sup b__________________________________________________________________________1 3 min 25 u00b0 c propylene 1 13 3 2 g 890 4 500 2 2 min 25 u00b0 c propylene 0 73 3 8 g 1 100 4 800 3 3 min 25 u00b0 c propylene 0 41 2 5 g 3 500 7 900 4 3 min 25 u00b0 c propylene 0 24 3 0 g 3 800 9 400 5 3 min 25 u00b0 c propylene 0 080 4 0 g 11 000 95 000 6 2 min 25 u00b0 c propylene 0 030 3 0 g 43 000 150 000 7 10 min 0 u00b0 c propylene 0 020 4 0 g 67 000 210 000 8 60 min 25 u00b0 c 1 hexene sup c 0 030 3 1 g 2 500 6 200 9 180 min 25 u00b0 c ethylene 0 17 sup d 0 050 2 8 g 50 72 000 100 000 10 180 min 25 u00b0 c ethylene 0 32 sup e 0 060 2 6 g 52 50 000 120 000__________________________________________________________________________ sup a concentration range of catalyst 2 65 3 05 mm sup b by gpc in 1 2 4trichlorobenzene vs polystyrene standards sup c concentration of 1hexene 6 00m sup d styrene sup e 1hexene the method of the invention clearly demonstrates that a silane compound as disclosed can serve as an effective chain transfer agent in the polymerization of olefins using a metallocene containing catalyst therefore the molecular weight of the resulting polymer or copolymer can be controlled by adding the appropriate amount of the silane furthermore the instant method may be used to prepare novel silyl terminated co polymers wherein one terminus of the co polymer is a silyl group preferably.