| 摘要 |
<p>PURPOSE: A porous nanoweb is provided to lower resistivity due to the nanoweb structure easily controlling porosity, thereby obtaining excellent battery performance and stability when using for a separation film of secondary battery. CONSTITUTION: A porous nanoweb comprises a first polymer having the melting temperature of 200°C or lower and a second polymer having the melting temperature of 210°C or higher. The porous nanoweb comprises a first nano fiber consisting of the first polymer and a second nano fiber consisting of the second polymer. The average diameter of the first and the second nano fiber is 0.005-5μm. The porosity of the porous nanoweb is 40-90% and the thickness of the porous nanoweb is 1-30μm. The first and the second nano fibers constitute a single nanoweb. The porous nanoweb comprises a first sub-nanoweb containing the first nano fiber and a second sub-nanoweb containing the second nano fiber. The porous nanoweb comprises complex nanofiber. The complex nanofiber comprises a core formed by the second polymer, and a sheath which is formed by the first polymer, surrounding the core. The content of the second polymer is 50-90wt%.</p> |
