ULTRA-FINE FIBROUS POROUS SEPARATOR HAVING SHUTDOWN FUNCTION AND METHOD FOR PRODUCING SAME

摘要

The present invention relates to an ultra-fine fibrous porous separator having a shutdown function and a method for producing same, wherein when a heat-resistant first porous membrane and the non-heat-resistant second porous membrane are calendered into a multi-layer structure and when heat is generated by sudden ion migration to localised pores or the entire part of the separator reaches a shutdown temperature, such that either part or all of a non-heat-resistant second porous membrane is melted and shut down, thereby blocking pores needing to be blocked. The ultra-fine fibrous porous separator having a shutdown function of the present invention comprises: a first porous membrane having a porous fibrous form in which the ultra-fine fibrous forms of a heat-resistant polymer and a swellable polymer coexist by the air electrospinning (AES) of a liquid mixture of a heat-resistant polymeric material having a melting point of at least 180°C and a swellable polymeric material; and a second porous membrane which is laminated onto one surface of the first porous membrane and which has an ultra-fine fibrous form obtained by the air electrospinning of a non-heat-resistant polymeric material having a melting point of not higher than 150°C.