Morphology and dynamic-mechanical properties of PVC/NBR blends reinforced with two types of nanoparticles

Yousefi

et al. 2015

JOM

Self Cite

Synergistic effects of nanoclay (NC) and carbon nanotube (CNT) as a physical and chemical hybrid on the properties of epoxy matrix were studied. The chemical hybrid of CNT-NC (CNC) was synthesized by high-temperature decomposition of methane on NC supports. The formation of CNTs on the NC surface was confirmed by transmission electron microscopy, scanning electron microscopy (SEM) and Raman spectroscopy. As-prepared CNCs were subsequently added into an epoxy matrix to make epoxy-CNC composites. The mixture of purified CNTs and NC as the physical hybrid of CNT-NC (PNC) was introduced into the epoxy matrix in order to fabricate epoxy-PNC composites. The relationship between the type of filler with the thermal and morphological performance of the epoxy-CNT-NC composite hybrids was investigated. The exfoliation characteristics of NCs and CNTs in epoxy nanocomposites were analyzed using x-ray spectroscopy (EDX) and SEM studies, respectively. Thermal behavior of the epoxy nanocomposites was studied by thermo-gravimetric-differential thermal analysis (TGA/DTG), the heat deflection temperature (HDT) test and dynamic mechanical analysis (DMA). The results indicated that the thermal characteristics of the epoxy including the degradation temperature (T deg ), HDT and glass transition temperature (T g ) relatively increased with the introduction of all the nanofillers, NC, CNT, PNC and CNC. The synergistic effects of CNT and NC were found to be more marked for the chemical hybrid compared to the physical one. In the case of CNC, it was observed that the CNTs attached to the clay sheets form a unique structure in which a 2D NC has several 1D CNTs attached to it. The enhanced homogeneous dispersion of NCs and CNTs in epoxy-CNC was clearly observed compared to epoxy-PNC.

Section: Epoxy Nanocomposites Based On Hybrids Of Cnt-ncmentioning

confidence: 99%

Thermal and Morphological Study of Epoxy Matrix with Chemical and Physical Hybrid of Nanoclay/Carbon Nanotube

Yousefi

et al. 2015

JOM

Self Cite

“…Physical blend of natural rubber (NR) and styrene butadiene rubber (SBR) have been widely used in automotive rubber tire industry which includes about 70% of entire rubber usage . A common approach to improve the final performance of rubbers is using reinforcing fillers such as fibers, carbon black, nanoclays, and carbon nanotubes . Fiber‐reinforced rubbers have gained a remarkable importance due to their unique advantages such as easy processability, anisotropy in mechanical properties, durability, and design against failure …”

Section: Introductionmentioning

confidence: 99%

“…2 A common approach to improve the final performance of rubbers is using reinforcing fillers such as fibers, 3 carbon black, 4,5 nanoclays, 6,7 and carbon nanotubes. 8 Fiber-reinforced rubbers have gained a remarkable importance due to their unique advantages such as easy processability, anisotropy in mechanical properties, durability, and design against failure. 9 NOMENCLATURE: E, elastic modulus; N, number of cycles; σy, yield strength; σult, ultimate tensile strength; σ max , maximum stress; σ min , minimum stress; ε, strain amplitude; ε r , ratcheting strain; R, stress ratio; phr, fiber content per hundred rubber In real engineering application, rubber-made components endure cyclic loading during their service with relatively large reversible elastic deformation.…”

Section: Introductionmentioning

confidence: 99%

Ratcheting response of nylon fiber reinforced natural rubber/styrene butadiene rubber composites under uniaxial stress cycles: Experimental studies

Vahidifar

Fatigue Fract Eng Mat Struct

et al. 2017

The present study intends to study the ratcheting response of nylon fiber reinforced natural rubber (NR)‐styrene butadiene rubber (SBR) composite samples under asymmetric stress cycles. Uniaxial tests conducted on composite samples have shown how influential the weight fraction of short nylon fibers on the stress‐strain curves/loops under monotonic and cyclic loads is. NR/SBR composite samples with various fiber contents of 0, 10, 20, 30, and 40 per hundred rubber (phr) were tested under asymmetric stress cycles. In these tests, stress‐strain hysteresis loops were progressively shifted over stress cycles resulting in progressive plastic strain accumulation. Over stress cycles, ratcheting strain progressed within the first few cycles with a relatively high rate, and as the number of cycles increased, this rate decayed resulting in a plateau in strain accumulation (shakedown). The ratcheting strain rate and magnitude resulting in shakedown were highly affected by the nylon fiber content. The experimental observations showed that this plateau (shakedown) occurred after a number of cycles in NR/SBR composite samples where the widths of hysteresis loops stayed unchanged. Samples with no fiber and that with 10 phr fiber content possessed high ratcheting rates leading samples to failure after a few stress cycles. Fracture surfaces in these samples were further analyzed through SEM investigation.

“…3 Since these materials are not vulcanized so they can be recycle and re-shape via a re-melting process similar a thermoplastic materials. [5][6][7] Carbon nanotubes (CNTs) are known as the ideal reinforcing fillers to produce high-performance nanocomposites with excellent mechanical, thermal, and electrical properties 8,9 compared with other fillers such as glass fiber, talc, calcium carbonate, carbon black, and carbon nanofiber. [5][6][7] Carbon nanotubes (CNTs) are known as the ideal reinforcing fillers to produce high-performance nanocomposites with excellent mechanical, thermal, and electrical properties 8,9 compared with other fillers such as glass fiber, talc, calcium carbonate, carbon black, and carbon nanofiber.…”

Section: Introductionmentioning

confidence: 99%

“…4 Reinforcing polymer matrix with various fillers continues to be one of the most important methods to overcome the shortages of polymer materials, which limit their applications, such as poor mechanical and thermal properties. [5][6][7] Carbon nanotubes (CNTs) are known as the ideal reinforcing fillers to produce high-performance nanocomposites with excellent mechanical, thermal, and electrical properties 8,9 compared with other fillers such as glass fiber, talc, calcium carbonate, carbon black, and carbon nanofiber. 10 The supreme reinforcing effect of this onedimensional filler (CNTs) is due to their unique mechanical, electrical, and structural properties, that is, very high aspect ratio, typically in the range of several thousand.…”

Section: Introductionmentioning

confidence: 99%

Effect of carbon nanotube on PA6/ECO composites: Morphology development, rheological, and thermal properties

Irani

J of Applied Polymer Sci

et al. 2017

Self Cite

Thermoplastic elastomer (TPE) nanocomposites based on polyamide-6 (PA6)/poly(epichlorohydrin-co-ethylene oxide) (ECO)/multiwall carbon nanotube (MWCNTs) were prepared by melt compounding process. Different weight ratios of ECO (20, 40, and 60 wt %) and two kinds of functionalized and non-functionalized MWCNTs were employed to fabricate the nanocomposites. The morphological, rheological, and mechanical properties of MWCNTs-filled PA6/ECO blends were studied. The scanning electron microscopy of PA6/ECO blends showed that the elastomer particles, ECO, are well-dispersed within the PA6 matrix. The significant improvement in the dispersibility of the carboxylated carbon nanotubes (COOH-MWCNTs) compared to that of non-functionalized MWCNTs (non-MWCNTs) was confirmed by transmission electron microscopy images. The tensile modulus of samples improved with the addition of both types of MWCNTs. However, the effect of COOH-MWCNTs was much more pronounced in improving mechanical properties of PA6/ECO TPE nanocomposites. Crystallization results demonstrated that the MWCNTs act as a nucleation agent of the crystallization process resulted in increased crystallization temperature (T c ) in nanocomposites. Rheological characterization in the linear viscoelastic region showed that complex viscosity and a non-terminal storage modulus significantly increased with incorporation of both types of MWCNTs particularly at low frequency region. The increase of rheological properties was more pronounced in the presence of carboxylic (COOH) functional groups, in the other words by addition of COOH-MWCNTs.