Mass transport to generate the channels in cellulose polymers by vacuum-assisted process

This study developed a pore-connected PP-CA membrane by coating cellulose acetate onto a polypropylene filter. A new method was proposed to attach a CA/glycerin coating layer to a porous PP support without a separate binder. The pores of CA and PP were interconnected using a vacuum filtration device. By adding glycerin to the CA chains, the membrane region became more flexible due to glycerin plasticization. Water passed through the membrane under pressure differences, resulting in the formation of interconnected pores between cellulose acetate and polypropylene. The pore size and quantity could be adjusted by varying the molar ratio of glycerin. Fourier transform infrared spectroscopy revealed the interaction between CA and glycerin, while thermogravimetric analysis showed that the membrane's thermal stability increased by approximately 20 °C after vacuum filtration. This simple and cost-effective manufacturing process holds potential for mass-producing separators in the lithium-ion battery industry.