Channels formation in cellulose materials by accelerated transport of gas molecules and glycerin

Abstract

In this study, a microporous separator was produced using cellulose acetate (CA), which demonstrates heightened thermal stability in comparison to existing materials like polypropylene (PP) or polyethylene (PE). Furthermore, a pliable component was integrated into the CA membrane using glycerin as the plasticizing agent. Subsequently, gas pressure was exerted onto these areas to induce the formation of nano-sized pores. Examination through Scanning Electron Microscopy (SEM) unveiled the presence of abundant pores in the glycerin-plasticized areas. This substantiates that the pores generated under gas pressure were not only more uniform but also smaller than those created under water pressure. The interaction between CA and glycerin was validated using Fourier-Transform Infrared Spectroscopy (FT-IR), offering confirmation that a portion of the glycerin was extracted following the application of gas pressure. Additionally, the application of Thermogravimetric Analysis (TGA) allowed for an assessment of the thermal stability of the CA membrane, along with a verification of glycerin's removal post gas pressure treatment. The findings indicated that the incorporation of glycerin diminished the thermal stability of the CA membrane due to the plasticization effect. Furthermore, it was observed that a minor quantity of glycerin still persisted after the gas pressure treatment. Following the analysis of gas permeation, the porosity of the CA membrane was quantified at 78.8 %, exhibiting an average pore size measuring 224 nm.

Keywords: Cellulose; Gas-pressure; Membrane; Pore control; Porosity.