Mechanical reinforcement of continuous flow spun polyelectrolyte complex fibers.

A simple continuous flow wet-spinning method to achieve mechanical reinforcement of the two oppositely charged biopolymers chitosan and gellan gum is described. The mechanical properties of these biopolymers are influenced by the order of addition. Using a facile method for mechanical reinforcement of gellan gum/chitosan fibers resulted in increases in Young's modulus, tensile strength, and toughness. Spinning gellan gum into chitosan resulted in the strongest fibers. We show that our fibers can provide a mechanical alternative for bio-fibers without the need of cross-linking. It is demonstrated that the fibers become ionically conducting in the presence of water vapor.