Process for polymerizing 1-olefins and catalyst therefor

A process for preparing a polymer of 1-olefin monomer comprising polymerizing said monomer in contact with a two-component catalyst, the first component being comprised of a solid titanium trichloride complex having the formula

• TiCl.sub.3 (AlR.sub.n X.sub.3-n).sub.x (C).sub.y
• wherein
• R is a hydrocarbon radical containing from 1 to 18 carbon atoms,
• X is a halogen,
• n is a number from 0 to 2,
• C is an organic complexing agent selected from compounds having the formula
• R'-O-R", R'-S-R" and R'-SH
• wherein R' and R" are independently hydrocarbon radicals containing from 1 to 15 carbon atoms,
• x is a number less than 0.3, and
• y is a number higher than 0.001, and the second component being comprised of an alkylaluminum hydride of the formula
• AlR'".sub.m H.sub.3-m
• wherein
• R'" is a hydrocarbon radical containing from 1 to 18 carbon atoms, and
• m is a number from 1 to 2.