Abstract
Using cellulose nanofibrils (CNF) in packaging under humid conditions is challenging due to their hygroscopicity, which causes an efficacy-failure of coating materials. Here, inspired by nature and plant cell walls, we developed a fully bio-based aqueous dispersion coating made of CNF/ polymerized lignin, where lignin was polymerized in situ in proximity to a CNF surface in dispersion via laccase-catalyzed oxidation. The polymerized lignin nanoparticles were evenly distributed on the fiber surface in CNF/ polymerized lignin dispersions, particularly in isopropyl alcohol (iPrOH) lignin fractions at a loading amount of 15 wt% and for an enzymatic polymerization of 6 h. This dispersion also demonstrated the formation of homogenous films with the highest hydrophobicity (a water contact angle of approx. 120°) among all tested formulations. The iPrOH-lignin fractions outperformed other fractions in enhancing the barrier properties of the coated paperboard, i.e., a twofold reduction in the water vapor transmission rate, a 52-fold reduction in the oxygen transmission rate, and excellent grease barrier properties (KIT rating of 12). These results indicate that aqueous dispersion coatings of CNF/ polymerized lignin reveal the structure–property relationship between the decoration of the CNF surface and the performance of the coating, which are a promising sustainable approach for providing barrier properties in packaging applications.
| Original language | English |
|---|---|
| Pages (from-to) | 5389-5405 |
| Journal | Cellulose |
| Volume | 32 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - Jun 2025 |
| MoE publication type | A1 Journal article-refereed |
Funding
Open access funding provided by Åbo Akademi University. Business Finland Project (SUSBINCO, No. 43674/31/2020) is acknowledged for the research funding to the current work. Mr. Liqiu Hu would like to acknowledge the financial support from the China Scholarship Council (Student ID 201908120107) to his doctoral study at ÅAU, Finland. Parts of research used Research Council of Finland Research Infrastructure “Printed Intelligence Infrastruture” (PII-FIRI).