Components formed of blow molded thermoplastic compositions are described. The blow molded thermoplastic compositions exhibit high strength and flexibility. Methods for forming the thermoplastic compositions are also described. Formation methods include dynamic vulcanization of a composition that includes an impact modifier dispersed throughout a polyarylene sulfide. A crosslinking agent is combined with the other components of the composition following dispersal of the impact modifier. The crosslinking agent reacts with the impact modifier to form crosslinks within and among the polymer chains of the impact modifier. The compositions can exhibit excellent physical characteristics at extreme temperatures and can be used to form, e.g., tubular member such as pipes and hoses and fibers.