M. Madani: Cationic and Zwitterionic Cellulose Derivatives: Synthesis, Properties, and Potential Applications

Abstract: 

This doctoral thesis investigates the chemical modification of cellulose to develop advanced functional materials. Cellulose is a natural, abundant, biodegradable, and renewable biopolymer with significant potential for sustainable material design. The study focuses on the synthesis, characterization, and functional evaluation of modified cellulose derivatives, particularly cationic, zwitterionic, and oxidized cellulose materials. The purpose of the study was to design and understand functional cellulose-based materials with tailored properties for biomedical and technological applications. By introducing specific chemical functionalities into cellulose, the research aimed to enhance properties such as antimicrobial activity, ionic conductivity, biocompatibility, and mechanical performance.

The research produced several important results. Cationic cellulose nanocrystals demonstrated the ability to interact with viruses and bacteria through electrostatic interactions. Oxidized cellulose nanocrystals were shown to function as effective crosslinking agents in hydrogel networks, producing injectable, self-healing, and mechanically robust hydrogels suitable for wound-healing applications. In addition, cationic cellulose was incorporated into electrospun nanofiber mats to create antibacterial wound dressing materials. Finally, zwitterionic cellulose-based hydrogels were developed with ionic conductivity and flexibility suitable for wearable strain sensor applications.

Key words: cationic cellulose, oxidized cellulose, zwitterionic cellulose, hydrogel, nanofiber mats, wearable sensors 

Opponent: Dr. Hannes Orelma, VTT

Custos: Assistant Prof. Jukka Niskanen, Aalto University School of Chemical Engineering

Link to electronic thesis: Thesis available for public display 7 days prior to the defence at Aalto University's public display page.

Link to the remote defense: LINK