The extractable material is removed by first dissolving it in a liquid which is not {HEAD ~ a solvent} for the matrix forming material to form {TAIL ~ a solution} 
The extractable material is removed by first dissolving it in a liquid which is not { HEAD ~ a solvent } for the matrix forming material to form { TAIL ~ a solution }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL