Abstract: An adhesive is disclosed. The adhesive is a blend of a tackifier and a polymer, having an elastomeric main chain and incorporating thermoplastic macromonomer side chain grafts, which can exhibit enhanced shear thinning and allow spray application of the adhesive onto a substrate. In one embodiment, the polymer main chain comprises a polymer of an isoolefin having about 4 to about 7 carbon atoms and a para-alkylstyrene, and the side chains comprise a grafted macromonomer, such as a terminally functionalized polystyryl chain of very narrow molecular weight distribution, attached to the para-alkyl group of the para-alkylstyrene. In another embodiment, the polymer comprises a polyolefin main chain and a norbornene terminated macromolecule copolymerized to introduce the side chains.