Tie layer composition and laminated structures containing same

Abstract

An adhesive composition comprising a plurality of selectively hydrogenated block copolymers, each of said block copolymers comprising at least one polymeric block containing predominantly monoalkenyl aromatic hydrocarbon monomer units and at least one polymeric block containing predominantly conjugated diolefin monomer units, at least one of which block copolymers is carboxylated and at least one of which block copolymers is not carboxylated and laminated structures comprising a plurality of polymeric layers tied together with said adhesive composition. The adhesive composition contains a relatively minor amount of carboxyl groups, on average, per polymer chain in the composition and is particularly useful in the preparation of laminated structures via coextrusion or similar processes, wherein the various layers are brought together in the molten phase while in motion, when one or more layers in the laminated structure comprises a polar group reactive with the carboxyl groups. Laminated structures prepared with the adhesive composition can be prepared and processed at higher temperatures than similar laminated structures heretofore known.