Articles, e.g. {HEAD ~ inflated sports balls} made of these alloys of polyurethanes and rubbers have surprisingly low air permeability and {TAIL ~ improved resiliency} 
have
Articles , e.g. { HEAD ~ inflated sports balls } made of these alloys of polyurethanes and rubbers have surprisingly low air permeability and { TAIL ~ improved resiliency }
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL