Electrospun single-walled carbon nanotube/polyvinyl alcohol composite nanofibers:structure–property relationships

Abstract

Polyvinyl alcohol (PVA) nanofibers and single-walled carbon nanotube (SWNT)/PVAcomposite nanofibers have been produced by electrospinning. An apparent increase inthe PVA crystallinity with a concomitant change in its main crystalline phaseand a reduction in the crystalline domain size were observed in the SWNT/PVAcomposite nanofibers, indicating the occurrence of a SWNT-induced nucleationcrystallization of the PVA phase. Both the pure PVA and SWNT/PVA compositenanofibers were subjected to the following post-electrospinning treatments: (i)soaking in methanol to increase the PVA crystallinity, and (ii) cross-linking withglutaric dialdehyde to control the PVA morphology. Effects of the PVA morphologyon the tensile properties of the resultant electrospun nanofibers were examined.Dynamic mechanical thermal analyses of both pure PVA and SWNT/PVA compositeelectrospun nanofibers indicated that SWNT–polymer interaction facilitated theformation of crystalline domains, which can be further enhanced by soaking thenanofiber in methanol and/or cross-linking the polymer with glutaric dialdehyde.