Investigation of nanofiber nonwoven meshes produced by electrospinning of cellulose nanocrystal suspensions in cellulose acetate solutions

摘要

The development of nonwoven meshes based on cellulose acetate (CA) reinforced by cellulose nanocrystals (CNC) is reported. The meshes were electrospun from 15 wt% CA (M-n = 30,000) in dimethylacetamide/ acetone (1:2, w/w) solutions with various concentrations of CNC dispersions. The investigated six levels of CNC dispersions in CA solutions were: 0, 0.075, 0.147, 0.225, 0.300 and 0.382 wt%, which corresponded to 0, 0.50, 1.00, 1.50, 1.99 and 2.55 wt% of CNC in solid fibers. The basis of the impact of CNC nano-particles on fiber diameter and morphology was explored by assessing their contributions to the viscosity, conductivity and homogeneity of CA/CNC solutions. CA/CNC nonwoven meshes spun from suspensions with 0.075 wt% CNC had best results in morphology and fiber uniformity. Additionally, mechanical properties of CA nonwoven meshes with five levels of CNC loading (0, 0.50, 1.00, 1.50 and 1.99 wt%) were examined. The CA nonwoven mesh with 0.50 wt% CNC showed best mechanical properties, and its elastic modulus (E) was improved to an average value of 1.68 GPa from 1.17 GPa of neat CA nanofiber nonwoven mesh. These improved meshes would have applications such as separation membranes, supports for catalysts and sensors, engineered tissues and other smart materials.