Thermal, viscoelastic and mechanical behavior of polypropylene with synthetic boehmite alumina nanoparticles

Abstract

Effects of nanofiller concentration and surface treatments on the morphology, thermal, viscoelastic and mechanical behaviors of polypropylene copolymer (PP)/boehmite alumina (BA) nanocomposites were investigated. Both untreated and treated BA particles with octylsilane (OS) and with sulphonic acid compound (OS2) were added up to 10 wt% to produce nanocomposites by melt mixing followed by film blow molding and hot pressing. Dispersion of BA was studied by scanning electron microscopy. Differential scanning calorimetry and wide-angle X-ray scattering were adopted to detect changes in the crystalline structure of PP. Thermooxidative degradation of the nanocomposites was assessed by thermogravimetrical analysis. Dynamic mechanical analysis served for studying the viscoelastic, whereas quasi-static tensile, creep and Elmendorf tear tests were used to detect changes in the mechanical performance. BA nanoparticles were finely dispersed in PP up to 10 wt%, even when they were not surface modified. The resistance to thermal degradation was markedly improved by BA nanomodification. Changes observed in the mechanical properties were attributed to BA dispersion, filler/matrix interactions and related effects because the crystalline characteristics of the PP matrix practically did not change with BA modification.

Mechanical properties of epoxy resins reinforced with synthetic boehmite (AlOOH) nanosheets

“…Meanwhile, Figure (a) shows that the fractured surface after hand breaking of 2 wt % AlOOH nanocomposites has a big hole, which is not observed in the fractured surface after tensile test [Figure (b)]. The enhanced ductility can be explained by a failure mode in which particle debonding with massive voiding occurs first, followed by void coalescence associated with matrix fibrillation …”

Characterization of polypropylene/polystyrene boehmite alumina nanocomposites: Impact of filler surface modification on the mechanical, thermal, and rheological properties

“…In addition to its good dispersibility, BA is a low‐cost filler that is easy to produce. BA particles range in the tens of nanometer (nm) in size and can be organically modified to enhance their interactions with polymer chains and permit their use with a wide range of polymers …”

“…reported that the incorporation of BA particles enhanced the stiffness and strength of PS. BA particles were also added to a PP matrix by Pedrazzoli et al . and their results indicate that the tensile modulus of the PP was improved.…”

“…However, their results also showed that BA particles slightly improved the resistance of LLDPE to thermo‐oxidative degradation and increased the tensile modulus and yield strength. There have been reports of BA particles that were incorporated into polymer matrices, such as polyamide 6 (PA6), poly(ethylene terephthalate), poly(ɛ‐caprolactone) (PCL), polylactide (PLA), poly(methyl methacrylate), epoxy, polyurethane (PU), and PP, among others . The findings of these studies indicate that the incorporation of BA nanoparticles produces composites with improved thermal stability, fire resistance, and tensile modulus.…”

Preparation and performance of nanoparticle‐reinforced chitosan proton‐exchange membranes for fuel‐cell applications

“…In line with previous studies, the pure CS showed characteristic bands at 2θs of 23 and 19°. The characteristic peaks at 2θs of 38 and 49° were attributed to the orthorhombic crystalline form of the boehmite nanofillers . The incorporation of boehmite nanofillers resulted in a reduction or even the disappearance of the characteristic peak at a 2θ of 23°; this was mainly due to the interference of nanofillers with orderly packed CS chains through interfacial interactions and, hence, the reduction of the crystalline domain of the polymer.…”