A multilayer sheet includes a core layer including a composition including about (60) to about (90) weight percent of polyphenylene, about (0) to about (20) weight percent of polystyrene, about (10) to about (20) weight percent of a hydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene, and optionally, a flame retardant additive; and a first cap layer disposed on a surface of the core layer, wherein the first cap layer includes polypropylene.