title: Improving mechanical properties of carbon nanotube fibers through simultaneous solid-state cycloaddition and crosslinking.
abstract: Individual carbon nanotubes (CNTs) exhibit exceptional mechanical properties. However, difficulties remain in fully realizing these properties in CNT macro-assemblies, because the weak inter-tube forces result in the CNTs sliding past one another. Herein, a simple solid-state reaction is presented that enhances the mechanical properties of carbon nanotube fibers (CNTFs) through simultaneous covalent functionalization and crosslinking. This is the first chemical crosslinking proposed without the involvement of a catalyst or byproducts. The specific tensile strength of CNTFs obtained from the treatment employing a benzocyclobutene-based polymer is improved by 40%. Such improvement can be attributed to a reduced number of voids, impregnation of the polymer, and the formation of covalent crosslinks. This methodology is confirmed using both multiwalled nanotube (MWNT) powders and CNTFs. Thermogravimetric analysis, differential scanning calorimetry, x-ray photoelectron spectroscopy, and transmission electron microscopy of the treated MWNT powders confirm the covalent functionalization and formation of inter-tube crosslinks. This simple one-step reaction can be applied to industrial-scale production of high-strength CNTFs.
authors.affiliation: Department of Chemistry, University of Tennessee, 1420 Circle Dr, Knoxville, TN 37996, United States of America.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Materials Science and Engineering, University of Tennessee, 1508 Middle Dr, Knoxville, TN 37996, United States of America.
authors.forename: Nitilaksha
authors.initials: N
authors.lastname: Hiremath
authors.affiliation: Center for Nanophase Materials Sciences Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, United States of America.
authors.forename: Kunlun
authors.initials: K
authors.lastname: Hong
authors.affiliation: Department of Chemistry, University of Tennessee, 1420 Circle Dr, Knoxville, TN 37996, United States of America.|Institute for Advanced Studies- IEAV/DCTA, São Jose dos Campos, SP 12228, Brazil.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Evora
authors.affiliation: Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 W Campbell, BE26, Richardson, TX 75080, United States of America.
authors.forename: Victoria H
authors.initials: VH
authors.lastname: Ranson
authors.affiliation: Materials Science and Technology Division, PO Box 2008, Oak Ridge, TN 37831, United States of America.
authors.forename: Amit K
authors.initials: AK
authors.lastname: Naskar
authors.affiliation: Department of Materials Science and Engineering, University of Tennessee, 1508 Middle Dr, Knoxville, TN 37996, United States of America.
authors.forename: Gajanan S
authors.initials: GS
authors.lastname: Bhat
authors.affiliation: Department of Chemistry, University of Tennessee, 1420 Circle Dr, Knoxville, TN 37996, United States of America.
authors.forename: Nam-Goo
authors.initials: NG
authors.lastname: Kang
authors.affiliation: Department of Chemistry, University of Tennessee, 1420 Circle Dr, Knoxville, TN 37996, United States of America.
authors.forename: Jimmy W
authors.initials: JW
authors.lastname: Mays