The catalyst component comprises {HEAD ~ a magnesium chloride support}, a titanium trichloride, {TAIL ~ an aluminum trichloride} and an organic phosphite 
The catalyst component comprises { HEAD ~ a magnesium chloride support } , a titanium trichloride , { TAIL ~ an aluminum trichloride } and an organic phosphite
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH