Extraction and application of cellulose microfibers from Washingtonia palm as a reinforcement of starch film
Laila Sajid, Oussama Azmami, Zakia El Ahmadi, Abbès Benayada, Aicha Boukhriss, Sanaâ Majid, Saïd Gmouh
Abstract
This work aims to optimize the industrial extraction conditions of cellulose microfibers (CMFs) from Washingtonia palm fiber for application in starch bio-composite films. The CMF extraction was a mixed process that combines caustic soda treatment with hydrogen peroxide bleaching in a stirred thermostatic bath. To study the yield, whiteness index and α-cellulose content, three variables were selected; NaOH and H 2 O 2 concentrations and treatment time. The optimum was determined using a Response Surface Methodology (RSM) approach for samples treated for 70 min with 5.21% NaOH and 5.54% H 2 O 2 . The optimized CMF was used to produce Starch/CMF bio-composite films with higher mechanical and barrier performance, which increased by 300% and 31%, respectively. Moreover, its moisture absorption and water solubility decreased by about 24% and 26%, respectively after adding 20 wt% CMF. In fact, morphological results showed that the higher CMF in the Starch/CMF 20 leads to the heterogeneous CMF distribution and agglomerates resulting in weakened starch films. As a result, the extracted CMF can be a competitive nanofabrication filler.