Abstract: Multi-phase blended pressure sensitive adhesives are described. The adhesives include a first phase containing at least one non-halogenated polyisobutylene material and a second phase comprising a thermoplastic elastomer. Exemplary thermoplastic elastomers include polyolefins, styrenic block copolymers, acrylic polymers and silicone polymers. Crosslinked adhesives, including those crosslinked with actinic radiation are also described.