Graft Modification of Chitosan

Collaborator: Dr. Pascale Champagne, Queen’s University

Chitin is a biopolymer produced by many living organisms including sea crustaceans and insects, and is the second most abundant polymer in the world, after cellulose. Chitosan (CTS) is the N-deacetylated derivative of chitin, composed of β (1→4)-links to 2-amino-2-deoxy-D-glucopyranose and to 2-acetamido-2-deoxy-D-glucopyranose. CTS is biocompatible, biodegradable, a hydrating agent, non-toxic, biologically tolerant, and resistant to the growth of bacteria, viruses, and fungi. These properties have resulted in CTS finding applications in water and wastewater treatment, agriculture and biopharmaceutics, cosmetics and toiletries, and the food and beverages industries.

However a major challenge in working with CTS is its poor solubility in organic solvents and its poor compatibility with most synthetic polymers.  We have developed a novel and simple strategy to modify CTS with a wide catalogue of well-defined molecular weight graft hydrophilic and hydrophobic polymers and copolymers (synthesized via nitroxide-mediated polymerization, or NMP) in homogeneous media to improve its compatibility with a wide range of solvents and polymers, and/or to impart a desired chemical functionality. We are currently exploring the use of graft-modified chitosan beads for removal of endocrine disruptors from water and graft modification of chitosan with flame retardant polymers.