Effect of polymer concentration on the morphology and mechanical characteristics of electrospun cellulose acetate and poly (vinyl chloride) nanofiber mats

Abstract

Cellulose Acetate (CA) and Poly (Vinyl Chloride) (PVC) nanofiber mats were electrospun into nanofibers. The morphology and mechanical properties of nanofiber mats were evaluated versus different solution concentrations. Solutions were prepared in mixed solvent systems of 2:1 (w/w) Acetone/N,N-Dimethylacetamide (DMAc) and 3:2 (w/w) Acetone/N,N-Dimethylformamide (DMF) for CA and 1:1 (w/w) Tetrahydrofuran/DMF for PVC. Scanning electron microscopy (SEM) images revealed that a beaded fibrous structure could be electrospun beginning at 10% CA in both Acetone/DMAc and Acetone/DMF solvent systems. The experimental results showed that smooth fibers were achievable at 14% CA in Acetone/DMAc and at 16% CA in Acetone/DMF solvent systems. For PVC, beaded fibers were formed at 12% PVC and smooth fibers were formed beginning at 14% PVC. Tensile strength tests showed that mechanical properties of the nonaligned nanofiber mats were influenced by solution concentration. With increasing solution concentration, the tensile strengths, break strains and initial moduli of the CA nanofiber mats increased. The effect of solution concentration on the tensile strengths of nanofiber mats was quite significant while it did not have any considerable effect on the tensile properties of the cast films.