Functionalization of carbon nanotubes with (3‐glycidyloxypropyl)‐trimethoxysilane: Effect of wrapping on epoxy matrix nanocomposites

Abstract

In this work, multiwalled carbon nanotubes (MWCNT), after previous oxidation, are functionalized with excess (3‐glycidyloxypropyl)trimethoxysilane (GLYMO) and used as reinforcement in epoxy matrix nanocomposites. Infrared, Raman, and energy‐dispersive X‐ray spectroscopies confirm the silanization of the MWCNT, while transmission electron microscopy images show that oxidized nanotubes presented less entanglement than pristine and silanized MWCNT. Thickening of the nanotubes is also observed after silanization, suggesting that the MWCNT are wrapped by siloxane chains. Field‐emission scanning electron microscopy reveals that oxidized nanotubes are better dispersed in the matrix, providing nanocomposites with better mechanical properties than those reinforced with pristine and silanized MWCNT. On the other hand, the glass transition temperature of the nanocomposite with 0.05 wt % MWCNT‐GLYMO increased by 14 °C compared to the neat epoxy resin, suggesting a strong matrix–nanotube adhesion. The functionalization of nanotubes using an excess amount of silane can thus favor the formation of an organosiloxane coating on the MWCNT, preventing its dispersion and contributing to poor mechanical properties of epoxy nanocomposites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44245.

Mechanical, thermomechanical, and creep performance of CNT embedded epoxy at elevated temperatures: An emphasis on the role of carboxyl functionalization

“…This enrichment in flexural strength upon addition of FCNTs can be attributed to these two facts (a) the stronger interfacial bond between CNT and epoxy due to the chemical linkage of functional group with both of them and (b) improved state of dispersion due to polar nature of FCNT preventing intermolecular interaction . In case of UCNT, the interfacial bonding is primarily due to the weak Van der Waal kind physical interactions between CNT and epoxy.…”

Silica Surface-Modification for Tailoring the Charge Trapping Properties of PP/POE Based Dielectric Nanocomposites for HVDC Cable Application

“…The bands at 2989∼2843 cm −1 corresponding to the C-H [28] vibrations shown in Fig.9 (e) demonstrate, that all four polar silanes are grafted onto the silica surface. The intensive C-H stretching band in Fig.9 (e) indicates the presence of the epoxy silane on the silica surface due to the high number of CH 2 units in the chemical structure of this silane, although the bands from the epoxy ring group were not detected [29]. The broad band around 1631 cm −1 visible in Fig.9 (f) and assigned to N-H stretching belongs to the amine group of the amino silane [28].…”

Efficient and Recyclable Heterogeneous Catalyst Based on PdNPs Stabilized on a Green-Synthesized Graphene-like Nanomaterial: Effect of Surface Functionalization

“…[34][35][36]38,39 In addition, it is observed that the amorphous carbon reflected by the D band is prominent, which means a high defect level. 40 To evaluate the disorder of GHN, the ratio of the D to G peak intensities (I D /I G ) is calculated (∼1.1), suggesting the partial amorphous nature of GHN resulting from its oxidation. 41 It was reported that during the oxidation reaction, disordered sp 3 -oxidized domains with various oxygen functional groups (such as epoxides, ketones, hydroxyls, carboxylic acids, and so forth) could surround the sp 2 graphitic domains.…”