It is preferred that at least about 60%, at least about 70%, {HEAD ~ at least about 80%}, at least about 90%, at least about 95%, and ideally about 100% of {TAIL ~ the particles} are of the same size 
of
It is preferred that at least about 60 % , at least about 70 % , { HEAD ~ at least about 80 % } , at least about 90 % , at least about 95 % , and ideally about 100 % of { TAIL ~ the particles } are of the same size
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH