The effect of sodium hydroxide concentration on yield and properties of Bacterial Cellulose membranes

摘要

Bacteria cellulose(BC)derived from Acetobacter xylinum strain possess several advantages such as elevated water holding capacity,high porosity and excellent mechanical strength.BC is useful to replace vegetal plant and applied into various industrial field such as papermaking,packaging and textile.In this study,BC membranes were produced from coconut water based consists of 8.0% sugar,0.5% ammonium sulphate and 1.0% acetic acid at pH 4.5,followed with the addition of 10.0% inoculum before subjected to static incubation for 7 days.This study evaluated the changes of BC membrane properties using different concentration of sodium hydroxide(NaOH)under room temperature within 24 hours.The morphological,physical,chemical structure and water vapour permeability(WVP)of BC were analysed using FESEM,XRD,FTIR and WVP analysis,respectively.Results show that BC is mainly consist of cellulose Iα with high crystallinity and smaller crystallite sizes.The differences in NaOH concentrations varied the fibrils diameter of cellulose,in accordance to FESEM images.The use of higher concentration of NaOH(>2.0%)gave a smooth cellulose structure with less porosity,thus reducing the WVP properties of BC.