The porous substrate is impregnated with {HEAD ~ a polymeric material} capable of bonding to the insulation of {TAIL ~ the conductors} 
The porous substrate is impregnated with { HEAD ~ a polymeric material } capable of bonding to the insulation of { TAIL ~ the conductors }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL