Designing High Performing Durable Bio-Based Coatings for Packaging Applications

This thesis focuses on developing new engineering knowledge essential for durable materials for sustainable packaging applications using renewable biopolymers. These include cellulose, extracted from plants, and chitin, sourced from mushrooms and food waste like crustacean exoskeletons. These natural polymers can form strong, high-performance films but are limited by moisture sensitivity and brittleness. Through chemical modification, compositional design, and controlled processing, this work demonstrates how their barrier and mechanical properties can be tuned to control and improve barrier and mechanical performance of renewable polymers. Chapter 2 presents a fully biodegradable multilayer structure composed of a cellulose nanocrystal–chitin nanofiber (CNC–ChNF) coating on paper laminated with poly(hydroxyalkanoates) (PHA). The design leveraged the oxygen barrier of CNC–ChNF, the mechanical support of paper, and the moisture resistance of PHA. The most effective configuration, achieved through double-sided PHA lamination, protected the hydrophilic coating from humidity and achieved barrier performance comparable to petroleum-based plastics like poly(ethylene terephthalate) (PET) and poly(ethylene) PE. Chapter 3 explores a crosslinked chitosan–citric acid–bentonite (Ch–CA–BNT) blend coated on PHA to improve barrier and mechanical performance without lamination. Crosslinking reduced water uptake, and the addition of BNT stabilized the coating’s strength, resulting in a bio-based material that maintained strong performance even after mechanical deformation. Chapter 4 introduces a single-layer approach using microfibrillated cellulose – CNC (MFC–CNC) blends treated with atomic layer deposition (ALD) of aluminum oxide (AlOx). The ALD process rendered the films more hydrophobic without compromising mechanical integrity, producing a single-layer biodegradable barrier film that eliminates the need for complex multilayer systems. In Chapter 5, poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL) were fabricated using 3D printing and evaluated under various printing conditions using a high-throughput mechanical characterization system (HTMECH) alongside conventional uniaxial testing. HTMECH enabled rapid screening of tensile properties and effectively captured trends related to material composition, layer thickness, and extrusion temperature, aligning well with traditional testing results. This chapter demonstrates HTMECH as a promising tool for accelerating the design and optimization of bio-based 3D-printed materials. Overall, this thesis establishes a framework for developing sustainable, high-performance packaging materials by integrating bio-based polymers, nanomaterials, and scalable processing strategies. The findings highlight how careful design of structure, chemistry, and processing can produce materials that meet performance requirements. Collectively, these results contribute to advancing biodegradable alternatives to petroleum-based plastics and provide valuable insights for future development of renewable, recyclable, and compostable packaging systems.

Name thesis:degree_name

Chemical Engineering, PhD

Grantor

Georgia Institute of Technology

Year dc:date.issued

2025

Author dc:creator

• Rolle, Javaz

Advisors dc:contributor.advisor

• Meredith, J. Carson
• Stingelin, Natalie

Committee members dc:contributor.committeemember

• Shofner, Meisha
• Luettgen, Christopher
• Kalaitzidou, Kyriaki

Language dc:language.iso

English

Handle dc:identifier.uri

https://hdl.handle.net/1853/80241

OAI identifier oai:identifier

oai:repository.gatech.edu:1853/80241