AIR-IMPERMEABLE FILM AND PNEUMATIC TIRE

摘要

Provided is an air-impermeable film which can be imparted with flexibility without the need of increasing the ratio of a rubber that constitutes a dispersed phase. An air-impermeable film comprising (A) a thermoplastic polyester elastomer which comprises a block copolymer containing a polyester as a hard segment and has a melting point of 180 - 230°C and (B) a rubber at a content ratio (i.e., (A)/(B)) of 90/10 - 40/60 by mass, wherein the component (A) is melt-kneaded with the component (B) to dynamically crosslinking these components with each other, thereby forming a continuous phase composed of the component (A) and a dispersed phase composed of the component (B). The film has an air permeation coefficient (80°C) of 5×1013 fm2/Pa·s or less and a Young's modulus of 120 MPa or less.