Melt-Mixed Thermoplastic Nanocomposite Containing Carbon Nanotubes and Titanium Dioxide for Flame Retardancy Applications

Abstract

The study of polymeric nanocomposites is a possible alternative to conventional flame retardants. The aim of the present work is to investigate the effects of carbon-nanotubes (CNT) and TiO2 nanoparticles (NPs) on the thermo-mechanical, flammability, and electrical properties of polypropylene (PP). In this work, PP-TiO2/CNT nanocomposites were obtained with TiO2/CNT mixtures (ratio 1:2) through the melt extrusion process, with different weight percentage of nanoparticles (1, 5, and 10 wt %). The PP-TiO2/CNT nanocomposites were characterized by DSC, TGA, MFI, FTIR, XRD, and SEM. It was possible to determine that the thermal stability of the PP increases when increasing the content of NPs. A contrary situation is observed in the degree of crystallinity and thermo-oxidative degradation, which decreased with respect to pure PP. The TiO2 NPs undergo coalition and increase their size at a lower viscosity of the nanocomposite (1 and 5 wt %). The mechanical properties decreased slightly, however, the Young’s modulus presented an improvement of 10% as well as electrical conductivity, this behavior was noted in nanocomposites of 10 wt % of NPs. Flammability properties were measured with a cone calorimeter, and a reduction in the peak heat release rate was observed in nanocomposites with contents of nanoparticles of 5 and 10 wt %

Pigmentation and Degradative Activity of TiO2 on Polyethylene Films Using Masterbatches Fabricated Using Variable-Frequency Ultrasound-Assisted Melt-Extrusion

“…On the other hand, the morphology of the compound with MFI 20 ( Figure 2 b), presented a more significant aspect of roughness in the polymer matrix than the one with an MFI = 2. This type of morphology has been observed in compounds of PP/TiO 2 [ 31 ]. However, the effect of the ultrasound treatment on the compound with MFI 50 ( Figure 2 c), showed less evidence of marks or craters in the polymer matrix and in the polymer-pigment interface, this may be because there is a greater relaxation of polymer chains, which are less entanglement due to the lower molecular weight [ 32 ].…”

Preparation and Characterization of Electrically Conductive Polymer Nanocomposites with Different Carbon Nanoparticles

“…The mixture leaves the extruder, is cooled, and cut to obtain a polymeric nanocomposite. Due to its simplicity, this process can be easily scaled to an industrial level, in addition to the fact that it does not generate waste and does not use solvents [35].…”

“…[37] In another embodiment, the ultrasound waves are applied constantly, gaining a dynamic frequency sweep in a given interval. [35,38,39].…”

Synthesis and Application of H-ZSM-5 Zeolites with Different Levels of Acidity as Synergistic Agents in Flame Retardant Polymeric Materials

“…TGA has been used in the evaluation of various composites with flame-retardant properties [47][48][49]. Figure 4 shows the TGA curves of composites with intumescent formulation (IF).…”