Effect of Carbon Nanofiber Functionalization on the Dispersion and Physical and Mechanical Properties of Polystyrene Nanocomposites

Abstract

Summary: The effect of peroxide functionalization of carbon nanofibers (CNF) on the physical and mechanical properties of polystyrene (PS)–CNF nanocomposites prepared via melt mixing was studied. The CNF functionalization was evidenced by Raman spectroscopy, comparing the ratio of peaks at 1 371 and at 1 590 cm−1 (peaks related to the disordered sp3‐hybridized carbon atom and to the graphitic structure of the sp2‐hybridized carbon atoms, respectively). The variation of the storage (E′) and tensile modulus (E) of the PS–CNF composites as a function of the untreated and peroxide treated CNF concentration were evaluated. Three different peroxide concentrations were used for treating the CNF. It was found that both E′ and E increase with CNF concentration and, in addition, increase further with the peroxide treated CNFs. Nonetheless, it was found that the greater the peroxide concentration used in treating the CNF, the greater the PS degradation via free radical attack on the polymer chain, with the corresponding negative effect on the storage and tensile modulus. Dispersion of the CNF was assessed using scanning and optical microscopy, and the positive effect of the peroxide treatment on the dispersion of the CNF is evidenced.Tensile stress‐strain behavior of PS/CNF nanocomposites.magnified imageTensile stress‐strain behavior of PS/CNF nanocomposites.

Chemical Modification of Carbon Nanofibers with Plasma of Acrylic Acid

“…The peak at 1 357 cm À1 is related to the disordered density of the sp 3 hybridized carbon atoms of the nanofiber and is designated as the D band, whereas the peak at 1 585 cm À1 is related to the ordered graphitic structure of the sp 2 hybridized carbon atoms of the nanofiber and is designated as the G band. [34] It is observed in Figure 8 that the maximum value of the G band presents a shift to a lower value. For pristine CNF the maximum appears at 1 585 cm…”

Interfacial thermal transport and structural preferences in carbon nanotube–polyamide-6,6 nanocomposites: how important are chemical functionalization effects?

“…[30][31][32] Despite these discouraging observations let us summarize some properties supporting an enhancement of l in the neighborhood of CNTs. The covalent functionalization of CNTs provides a way to engineer the CNT-polymer interface for favorable mechanical [35][36][37][38] and thermal [39][40][41] composite properties. 33 Transversal nanotube modes at low wave numbers can act as a minor enhancement factor for the interfacial heat transport.…”

Carbon Nanofibers‐Poly‐3‐hydroxyalkanoates Nanocomposite: Ultrasound‐Assisted Dispersion and Thermostructural Properties

“…Insonation [17,18], magnetron sputtering [19], spark plasma sintering [20], laser pyrolysis [21], and laser evaporation [22], and so forth, were employed to enhance the dispersion. In addition, surface functionalization was also reported to be an important way of improving the dispersion of nanoparticles into the polymer matrix [23][24][25]. While local turbulence due to the implosion of microbubbles from acoustic cavitation helps to disperse the carbon nanoparticles, the same high shear force could result in polymer degradation, thus affecting the thermomechanical properties of the fabricated material.…”