Unique copolymers comprising propylene, ethylene and/or one or more
unsaturated comonomers are characterized as having: at least one,
preferably more than one, of the following properties: (i) .sup.13C NMR
peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm,
the peaks of about equal intensity, (ii) a B-value greater than about 1.4
when the comonomer content of the copolymer is at least about 3 wt %,
(iii) a skewness index, S.sub.ix, greater than about -1.20, (iv) a DSC
curve with a T.sub.me that remains essentially the same and a T.sub.max
that decreases as the amount of comonomer in the copolymer is increased,
and (v) an X-ray diffraction pattern that reports more gamma-form
crystals than a comparable copolymer prepared with a Ziegler-Natta
catalyst These polypropylene polymers are made using a nonmetallocene,
metal-centered, heteroaryl ligand catalyst. These polymers can be blended
with other polymers, and are useful in the manufacture of films, sheets,
foams, fibers and molded articles.