PURPOSE: To obtain a compound excellent in flowability, heat distortion temperature, strengths and impact resistance and useful for pressure pipes, storage tanks, etc., by including a chlorinated PVC, a high rubber graft copolymer, a chlorinated PE and a stabilizer.

CONSTITUTION: There is provided the objective compound comprising a chlorinated PVC (CPVC) (A) containing 63-70 wt.% chlorine (CPVC is produced from a PVC having an intrinsic viscosity of 0.4-1.6), a high rubber graft copolymer (B) of a rubbery polydiene with one or more hardening monomers (e.g. vinylaromatic monomers) (the graft copolymer is selected from at least one of the group consisting of a high rubber ABS graft copolymer having a Shore D hardness of 64 or below and a high rubber non-ABS polydiene having a Shore hardness D of 42), a chlorinated PE (C) containing 30-40 wt. % chlorine and a stabilizer (D) (e.g. methyltin) for component A.