Polymer nanofibers reinforced with cellulose nanocrystals

Abstract

Cellulose nanocrystals (CNCs) have been used as effective reinforcing nanofillers for a variety of polymer nanofibers, taking advantage of their high- modulus and high-strength mechanical properties. Continuous polymer nanofibers incorporated with various contents of CNCs were fabricated using a simple and versatile electrospinning technique driven by a high-voltage electric field. Prior to the electrospinning process, CNCs were dispersed with polymers in solutions. Effects of the addition of CNCs on solution properties were investigated and correlated with the morphology and diameter of the nanofibers. Polymer nanocomposite fibers, usually several hundreds of nanometers in diameter, were produced as either randomly oriented porous mats or uniaxially aligned mats. CNCs were highly aligned along the fiber long axis. Thermal analysis suggested that the incorporation of CNCs influences thermal behaviors of polymer nanofibers, such as glass transition temperatures and melting enthalpies. Increases in tensile strength, Young’s modulus, and elastic modulus have been demonstrated from mechanical studies of the nanocomposite fibers containing CNCs.