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  • Using interfacial behavior and adsorption kinetics measurements as a predictor of bulk hydrophobic development of paper supercritically impregnated with food-grade waxes
Title: Using interfacial behavior and adsorption kinetics measurements as a predictor of bulk hydrophobic development of paper supercritically impregnated with food-grade waxes
Abstract Supercritical Impregnation methods are becoming popular in the development of food packaging materials. Bulk functional improvements of cellulose substrates using this method may be influenced by interfacial interactions between the impregnated solutes and cellulose. Hence, an interfacial adsorption kinetics study of solute molecules onto the substrate can provide insight on bulk property development, leading to an optimized packaging material with improved functionality. Paper substrates were impregnated with two food-grade waxes: Alkyl Ketene Dimer (AKD) and Carnauba Wax (CW). Hydrophobic development was monitored over a 3-week period. A quartz crystal microbalance (QCM-D) was used to determine interfacial characteristics and behavior of each wax with cellulose, and adsorption kinetics were quantified to compare the mass transfer processes of each wax at the interface. AKD significantly contributed to the substrate’s hydrophobic development over time. CW generated mildly hydrophobic substrates only when heated. AKD strongly adhered to the cellulose fibers at the interface, and demonstrated a 3-stage kinetic adsorption process, tentatively assigned (i) diffusion through the solvent; (ii) diffusion through the substrate; and (iii) attachment onto the fibers. CW readily washed off the cellulose surface, demonstrating only the first adsorption process. The different chemical structures also impacted these behaviors, as did concentration and temperature. Graphical Abstract  more » « less
Award ID(s):
2018004 2148764
PAR ID:
10539330
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Cellulose
Volume:
31
Issue:
11
ISSN:
0969-0239
Page Range / eLocation ID:
6867 to 6884
Subject(s) / Keyword(s):
Quartz Crystal Microbalance Adsorption kinetics Interfaces Cellulose Supercritical Impregnation Hydrophobicity
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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