However, since {HEAD ~ the concentration} of the polar vinyl compound is low, the pressure crystallization must be performed at further lower temperatures, thereby bringing about {TAIL ~ a further decrease} in separation efficiency 
However , since { HEAD ~ the concentration } of the polar vinyl compound is low , the pressure crystallization must be performed at further lower temperatures , thereby bringing about { TAIL ~ a further decrease } in separation efficiency
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH