Porous C2H3O2-substituted cellulose with thermal stability based on sodium chloride

Abstract

In this study, we fabricated porous membrane based on C2H3O2-substituted cellulose (ASC) by adding NaCl to a low cost and pro-environmental process. NaCl exists as an ionic aggregate in the ASC polymer, interacting with the functional group of polymer and increasing the distance between the chains. In the TGA data, the ASC/NaCl composite exposed at 8 bar showed higher thermal stability than the composite before applying water pressure. This means that NaCl interacts with the functional group of ASC. Thus, the ASC/NaCl complex was plasticized as the interaction between polymer chains was disrupted. The interaction between NaCl and functional group of ASC was measured by using FT-IR spectroscopy. Through FT-IR, it was found that NaCl, which is ionic aggregates, slightly interacts with the hydroxyl groups of ASC. Plasticized regions of the ASC/NaCl composites became small micron-sized pore, applying hydrostatic force at 8 bar. The small micron-sized pores were measured by water flux and gas permeability (i.e. Gurley value). Average water flux data was 4.7 L/m2h and average Gurley value was 14.29 s/cc. The pore morphology of surface and cross section of the ASC/NaCl composites were confirmed by SEM. Eventually, we succeeded in manufacturing the ASC/NaCl composites with small micron-sized pores for thermal stable separator at low cost.