The resulting mixture is then contacted with {TAIL ~ the co catalyst component} for {HEAD ~ a shorter second contact time} up to 20 seconds 
The resulting mixture is then contacted with { TAIL ~ the co catalyst component } for { HEAD ~ a shorter second contact time } up to 20 seconds
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH