title: Incorporation of liquid-like multiwalled carbon nanotubes into an epoxy matrix by solvent-free processing.
abstract: Covalent attachment of 2,2'-(ethylenedioxy)-diethylamine to multiwalled carbon nanotubes (MWCNTs) produced amino-functionalized MWCNTs which behaved like liquids at ambient temperature. These liquid-like MWCNTs (l-MWCNTs) could be homogeneously dispersed and chemically embedded in an epoxy matrix by solvent-free processing. In contrast, solid MWCNTs (s-MWCNTs) functionalized by 1,8-diaminooctane were poorly dispersed in epoxy although they possess chemical structures and functionalization comparable to l-MWCNTs. An epoxy composite filled with pristine MWCNTs (p-MWCNTs) was also fabricated in the absence of a solvent at the same loading for comparison. The molecular level coupling of l-MWCNTs and epoxy provided significant improvements in overall mechanical properties relative to those composites containing p-MWCNTs and s-MWCNTs. The Young's modulus, storage modulus, tensile strength, failure strain and toughness of neat epoxy were increased by 28.4, 23.8, 22.9, 24.1 and 66.1%, respectively, by adding 0.5 wt% of l-MWCNTs. Thus, functionalized carbon nanotubes in liquid form contributed to better dispersion and superior interfacial bonding with the epoxy matrix, thereby facilitating greater mechanical reinforcement efficiency.
authors.affiliation: Ministry-of-Education Key Laboratory for Green Preparation and Application of Functional Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062, People's Republic of China. Center for Advanced Materials Technology (CAMT), School of Aerospace, Mechanical and Mechatronic Engineering, J07, University of Sydney, Sydney, NSW 2006, Australia.
authors.forename: Ying-Kui
authors.initials: YK
authors.lastname: Yang
authors.forename: Lin-Juan
authors.initials: LJ
authors.lastname: Yu
authors.forename: Ren-Gui
authors.initials: RG
authors.lastname: Peng
authors.forename: Yuan-Li
authors.initials: YL
authors.lastname: Huang
authors.forename: Cheng-En
authors.initials: CE
authors.lastname: He
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Liu
authors.forename: Xian-Bao
authors.initials: XB
authors.lastname: Wang
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Xie
authors.forename: Yiu-Wing
authors.initials: YW
authors.lastname: Mai