Carbon nanotube reinforced poly(trimethylene terephthalate) nanocomposites: Viscoelastic properties and chain confinement

Abstract

Through a very facile route, a new class of nanocomposites involving poly(trimethylene terephthalate; PTT) and multiwalled carbon nanotubes (MWCNTs) was developed which was found to be high performance engineering material showing high modulus. Morphological, mechanical, viscoelastic, and thermal properties of the PTT nanocomposites with varying compositions of MWCNT were systematically studied and the results were analyzed. The dynamic mechanical and tensile properties of all the nanocomposites were seen to be enhanced with the addition of MWCNT and the sample containing 2 wt% MWCNT showing a storage modulus as much as 9.4 × 108 GPa. The results were correlated with the morphological features obtained from scanning electron microscopy and transmission electron microscopy. Coefficient of effectiveness, degree of entanglement density, and reinforcement efficiency factor were estimated from the storage modulus values and, in addition, the degree of chain confinement also could be quantified. Furthermore, theoretical modelling was also done on the elastic properties of the composites. The crystallization temperature, glass transition temperature, and percentage crystallinity were estimated for all the nanocomposites and it was found that the sample with 3 wt% MWCNT content exhibited the highest glass transition temperature of 68.2°C. POLYM. ENG. SCI., 59:E435–E445, 2019. © 2018 Society of Plastics Engineers

Reduced graphene oxide / epoxy nanocomposites with enhanced dielectric, mechanical, thermomechanical and thermal properties

“…Similar observations have been reported in the literature. [50][51][52][53] But in case of Ep/G-1.8, storage modulus value predicted by the theoretical models are in accordance with that of experimental results.…”

“…Rule of mixtures is one of the easiest methods to describe the reinforcing efficiency of a nanofiller, in which E ′ can be effectively calculated using relationwhere E ′ c and E ′ m are the storage modulus values of Ep/G nanocomposite and neat matrix, respectively, and V f is the volume fraction of rGO. 50…”

“…Later, considering the extent of physical and chemical interaction between matrix and filler, Guth amended Einstein’s equation as 50 Figure 5(f) represents the storage modulus values determined theoretically at 140°C using rule of mixtures, Einstein’s model and Guth model. Experimental values were found to be higher than theoretically predicted values in all three models studied.…”

“…However at higher concentrations, the formation of agglomerates (Figure 4(d) and (e)) can hinder the curing between the epoxy molecules as a result of which the temperature corresponding to E 00 peak shifted to the lower value. 45,50 Loss tangent. The variation of tan δ with temperature for epoxy nanocomposites is shown in Figure 5(d).…”

“…where E 0 c and E 0 m are the storage modulus values of Ep/G nanocomposite and neat matrix, respectively, and V f is the volume fraction of rGO. 50 Einstein included the concept of adhesion between matrix and filler and modified the relation as…”