Hydrophobic molded pulp based on partially grafted fibers dispersible in water. Part 1: comparison of the physical properties of recycled paper produced from hydrophobized paper treated by gas grafting with palmitoyl chloride or by internal AKD addition
Year: 2026
Type: article
Abstract: Conventional sizing agents often suffer from limitations such as pH dependency, insufficient hydrophobicity, and delayed development of water repellency. To overcome these drawbacks, this study applied a gas grafting treatment with palmitoyl chloride at 200 °C, forming ester bonds with cellulose hydroxyl groups and thereby imparting immediate and stable hydrophobicity. This approach enabled the fibers to retain a portion of hydrophilic surface area, ensuring both water resistance and fiber dispersibility during recycling. Water absorption and recycling performance were compared between gas-grafted handsheets and AKD-sized handsheets under different pulping temperatures. Even with minimal reagent dosage, gas-grafted sheets exhibited markedly lower Cobb values and maintained hydrophobicity after repulping at 50 °C, although with some reduction in tensile strength. In contrast, AKD-sized sheets retained mechanical integrity but showed a significant decline in water resistance when exposed to hot conditions, due to the melting and partial dissolution of AKD. Overall, these findings demonstrate that gas grafting with palmitoyl chloride provides a promising strategy for producing recyclable, water-resistant paper or molded pulp, particularly suitable for applications requiring thermal stability such as food packaging and disposable containers.
Source: Journal of Wood Science
Institutions: Kangwon National University, Centre Technique du Papier
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,990
OpenAlex ID: W7162005910