2) initiator for the polymerizable monomer starting materials present in an amount from 0.1 to approximately 2 parts by weight per 100 parts by {HEAD ~ weight} of the polymerizable monomer starting {TAIL ~ materials}, 
2 ) initiator for the polymerizable monomer starting materials present in an amount from 0.1 to approximately 2 parts by weight per 100 parts by { HEAD ~ weight } of the polymerizable monomer starting { TAIL ~ materials } ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH