Stereospecific polypropylene macromers having a high percentage of vinyl terminal bonds and a method for preparing them are provided. The stereospecific polypropylene macromers have number average molecular weights (M.sub.n) of about 2,000 Daltons to about 50,000 Daltons, and the total number of vinyl groups per 1000 carbon atoms is greater than or equal to 7000.div.M.sub.n. The method for preparing the macromers involves:a) contacting, in solution, at a temperature from about 90.degree. C. to about 120.degree. C., two or more propylene monomers with a catalyst composition comprising a chiral, stereorigid transition metal catalyst compound; andb) recovering stereospecific polypropylene chains having number average molecular weights of about 2,000 Daltons to about 50,000 Daltons and significant vinyl unsaturation.