title: MWCNTs/P(St-co-GMA) composite nanofibers of engineered interface chemistry for epoxy matrix nanocomposites.
abstract: Strengthened nanofiber-reinforced epoxy matrix composites are demonstrated by engineering composite electrospun fibers of multi-walled carbon nanotubes (MWCNTs) and reactive P(St-co-GMA). MWCNTs are incorporated into surface-modified, reactive P(St-co-GMA) nanofibers by electrospinning; functionalization of these MWCNT/P(St-co-GMA) composite nanofibers with epoxide moieties facilitates bonding at the interface of the cross-linked fibers and the epoxy matrix, effectively reinforcing and toughening the epoxy resin. Rheological properties are determined and thermodynamic stabilization is demonstrated for MWCNTs in the P(St-co-GMA)-DMF polymer solution. Homogeneity and uniformity of the fiber formation within the electrospun mats are achieved at polymer concentration of 30 wt %. Results show that the MWCNT fraction decreases the polymer solution viscosity, yielding a narrower fiber diameter. The fiber diameter drops from an average of 630 nm to 460 nm, as the MWCNTs wt fraction (1, 1.5, and 2%) is increased. The electrospun nanofibers of the MWCNTs/P(St-co-GMA) composite are also embedded into an epoxy resin to investigate their reinforcing abilities. A significant increase in the mechanical response is observed, up to >20% in flexural modulus, when compared to neat epoxy, despite a very low composite fiber weight fraction (at about 0.2% by a single-layer fibrous mat). The increase is attributed to the combined effect of the two factors the inherent strength of the well-dispersed MWCNTs and the surface chemistry of the electrospun fibers that have been modified with epoxide to enable cross-linking between the polymer matrix and the nanofibers.
authors.affiliation: Sabancı University, Materials Science and Engineering, Advanced Composites and Polymer Processing Laboratory, 34956 Tuzla, Istanbul, Turkey.
authors.forename: Elif
authors.initials: E
authors.lastname: Özden-Yenigün
authors.forename: Yusuf Z
authors.initials: YZ
authors.lastname: Menceloğlu
authors.forename: Melih
authors.initials: M
authors.lastname: Papila
mesh_terms: D004853:Epoxy Resins / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011789:Quantum Theory; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D014783:Viscosity; D017155:Wettability
chemical_list: D004853:Epoxy Resins; D037742:Nanotubes, Carbon