Multilayer polymeric structure

A multi-layer thermoformable polymer structure or sheet comprising:

• a) at least one thermoplastic polyolefin substrate layer,
• b) at least one styrenic-based polymer capstock layer, having a thickness of from 0.075 to 2.5 mm, wherein said styrenic-based polymer is selected from the group consisting of polystyrene, high-impact polystyrene (HIPS), acrylonitrile-butadiene-styrene (ABS) copolymers, acrylonitrile-styrene-acrylate (ASA) copolymers, styrene acrylonitrile (SAN) copolymers, methacrylate-acrylonitrile-butadiene-styrene (MABS) copolymers, styrene-butadiene copolymers (SB), styrene-butadiene-styrene block (SBS) copolymers and their partially or fully hydrogenated derivatives, styrene-isoprene copolymers, styrene-isoprene-styrene (SIS) block copolymers and their partially or fully hydrogenated derivatives, and styrene-methyl methacrylate copolymers (S/MMA), and
• c) a tie layer, having a thickness of from 0.05 to 1 mm, consisting of copolymers selected from the group consisting of olefinic acrylate copolymers having a homogeneous or heterogeneous distribution of compositions and molecular weights, copolymers of olefin and (meth)acrylic acid which can be partially or fully in the salt form, and mixtures thereof, wherein said tie layer has a tensile modulus of greater than 300 psi, as measured by ASTM D638,
• wherein the tie layer is directly adjacent to, and in between the at least one polyolefin-based substrate layer and the at least one styrenic-based polymer layer,
• wherein the layers a), b) and c) are coextruded together, and
• wherein said at least one substrate layer is thicker than said at least one capstock layer and tie layer combined, and
• wherein the thermoplastic polyolefin of the at least one substrate layer contains at least one polypropylene component and at least one elastomer component, where the at least one elastomer component includes at least one ethylene/alpha-olefin copolymer, at least one styrenic block copolymer, or a mixture thereof.