Coating based on cellulose from oil palm empty fruit bunches and chitosan doped by Ag+: multivariate optimization and DFT analysis

Abstract

The development of a cellulose nanocrystals/chitosan coating material doped with Ag⁺ (CNCs/CAg) has been carried out. Oil palm empty fruit bunches were used to obtain cellulose nanocrystals (CNCs). The influence of several parameters, such as water absorption, contact angle, and adhesive strength, on the reaction performance, was investigated using multivariate statistical modeling response surface methodology (RSM). Based on XRD, FTIR, and particle size analyzer (PSA) analyses, CNCs were successfully extracted. The optimum formulation based on RSM was obtained at the ratio of CNCs/chitosan, Ag amount, and stirring time of 2, 0.03 g, and 3 hours, respectively. The synthesized CNC/CAg composite has good potential as a coating material based on the water resistance, adhesive strength, and contact angle tests. This coating material has low water absorption, good adhesive strength, and is hydrophobic, making it suitable as a good coating. Additionally, CNCs/CAg remarkably inhibits the growth of S. aureus. Based on DFT analysis, Ag+ doped on the CNCs/chitosan showed better structural stability.