Effect Of Organic Montmorillonite Research Articles

Effect of Organic Montmorillonite on Rheological Properties of Sasobit Warm-Mix Asphalt and Analysis of Its Ultraviolet Aging Behaviors

Effect of Organic Montmorillonite on Rheological Properties of Sasobit Warm-Mix Asphalt and Analysis of Its Ultraviolet Aging Behaviors

Effect of Organic-Montmorillonite on rheological performance of Bio-Asphalt composites with various oxidative aging

Several previous studies have demonstrated that bio-asphalt derived from Waste Cooking Oil (WCO) displays superior performance in cracking resistance at low and medium temperature, but inferior in high temperature rutting resistance. This study aims to further improve the rutting resistance of WCO based bio-asphalt by a compound modification with Organized Montmorillonite (OMMT). One neat asphalt binder with penetration grade of 90 is selected in this study. The WCO based bio-oils are firstly mixed with neat binders followed by further modified with the OMMT additives. The frequency sweep, linear amplitude sweep (LAS) and multiple stress creep recovery (MSCR) tests are respectively conducted for evaluation of the linear viscoelastic properties, fatigue and rutting resistance. Experimental results demonstrate again that the fatigue resistances of bio-binders are improved compared to the base asphalt whereas the addition of bio-oil obviously reduces the binder rutting resistance at high temperature. However, the OMMT addition into the bio-asphalt is found to effectively enhance the rutting resistance when increasing the OMMT content without compromising the fatigue performance. Therefore, it can be preliminary concluded that the Bio/OMMT compound modification approach can be utilized to address the rutting potential concern of WCO based bio-binders at high temperature. Furthermore, the Response Surface Methodology (RSM) is employed to model the rheological properties of Bio/OMMT compound modified binder under various modifier weights, in which the damage characteristic and performance index can be effectively estimated.

Laboratory investigation on effects of organic montmorillonite on performance of crumb rubber modified asphalt

Laboratory investigation on effects of organic montmorillonite on performance of crumb rubber modified asphalt

Effect of Organic Montmorillonite on Properties of High-viscosity Modified Asphalt

In order to investigate the effect of organic montmorillonite (OMMT) and its content on properties of high-viscosity modified asphalt, a series of laboratory tests were carried out through zero shear viscosity (ZSV) at 60 °C, rutting factor, ductility at 5 °C, and fatigue factor to analyze high-temperature, low-temperature and anti-fatigue properties of high-viscosity modified asphalt with different OMMT contents. The results show that OMMT/high-viscosity modifier (HVM) composite modification can improve obviously high-temperature performance and fatigue resistance of high-viscosity modified asphalt, but the best improvement effect can be achieved only when adding proper amount of OMMT. The addition of a small amount of OMMT has little effect on low-temperature performance of high-viscosity modified asphalt, but when the content of OMMT exceeds 4%, its low-temperature performance will decrease significantly. The addition of OMMT can improve the temperature sensitivity of high-viscosity modified asphalt’s high-temperature performance, but reduces the temperature sensitivity of its fatigue resistance.

Effect of organic montmorillonite on microstructure and properties of the OMMT/EVA/Asphalt composites

In order to improve the aging resistance and rutting resistance of the asphalt, a novel OMMT/EVA/asphalt composite was prepared by using organic montmorillonite (OMMT) and ethylene vinyl acetate (EVA) as modifiers via melt blending method. The microstructure and morphology of the EVA/asphalt composites and the OMMT/EVA/asphalt composites were characterized by X‐ray diffraction (XRD) and fluorescence microscopy (FM), respectively. XRD patterns indicate that the layers of OMMT are peeled off, and an exfoliated structure is formed. FM images show that a network structure appears between EVA and asphalt. The properties of the OMMT/EVA/asphalt composites were investigated by storage stability test, rotating thin film oven test (RTFOT), and dynamic shear rheometer (DSR), respectively. The results show that OMMT/EVA/asphalt composites exhibit better storage stability and aging resistance than that of EVA‐modified asphalt. Moreover, the obtained composites also show an increase in softening point and complex modulus (G*), and a decrease in penetration and phase angle (δ), which indicate that the OMMT/EVA/asphalt composites display good rutting resistance, high elasticity, and superior anti‐cracking properties. POLYM. COMPOS., 39:1959–1966, 2018. © 2016 Society of Plastics Engineers

Analysis of crystalline structure and morphology of isotactic polypropylene under the coexistence of organic montmorillonite particles and shear flow

In this work, the different effects of organic montmorillonite (OMMT) particles and shear flow on the crystallization behavior of isotactic polypropylene (iPP) were discussed. While neat iPP and OMMT filled iPP were treated using the multistage stretching extrusion technology, changing the number of laminating-multiplying elements (LMEs) can obtain samples with different dispersion degree of OMMT particles and different orientation degree of molecular chains. With the increase of LME number, the content of β-crystal in neat iPP increased. But for OMMT/iPP composites, decreasing LME number caused the increase of content of β-crystal. The experimental results showed that the shear flow and large OMMT aggregations were essential factors for the formation of β-crystal in composites, and the crystalline morphology strongly depended on the size of OMMT particles. The scanning electron microscope (SEM) images of sample with 3 wt% of OMMT particles and without LME illustrated that β-transcrystallinity, fan-shaped β-crystal and α-spherulite were induced by different size of OMMT particles, respectively. A schematic was proposed to describe the formation mechanism of α-crystal and β-crystal under the coexistence of OMMT particles and shear flow.

Effect of organic montmorillonite on the performance of modified waterborne potassium silicate zinc-rich anti-corrosion coating

In this work, montmorillonite (MMT), as an anti-settling agent, was added to modified waterborne potassium silicate zinc-rich coating (MWPC), aiming at improving its anti-corrosion performance. Three MMTs were elected for anti-settling agents , including MMT, organo-montmorillonites (OMMT1 and OMMT2) which are modified by HOOC(CH2)17NH3+, and CH3(CH2)17NH3+, respectively. The effects of type and amount of MMT on the mechanical property and appearance of MWPC were investigated by mechanical tests and scanning electron microscope. Polarization curve and electrochemical impedance spectroscopy in 3.5 % sodium chloride solution were used to evaluate the corrosion protection performances and coating porosity. Fourier transform infrared (FTIR) spectroscopy confirmed that the organic functional group was successfully reacted with emulsion, which increased the performance of MWPC. The results also showed that OMMT modified by HOOC(CH2)17NH3+ exhibited better effects than that modified by CH3(CH2)17NH3+.

Effect of organic montmorillonite on the hot storage stability of asphalt modified by waste packaging polyethylene

In this paper, waste polyethylene (WPE), a large class of waste plastic packaging, and organic montmorillonite (OMMT) were employed as the polymer modifier and additive to modify base asphalt, and then hot storage stability of modified asphalt was studied. Structure of the modified asphalt was characterized with X‐ray diffraction and fluorescence microscopy. Moreover, the hot storage stability of WPE‐modified asphalt was investigated by Fourier‐transform infrared analysis, differential scanning calorimetry, and thermal gravimetry. Results show that an exfoliated structure is formed in the modified asphalt after adding OMMT. The WPE modifier particles become smaller and are more uniformly dispersed in the modified asphalt system after adding OMMT. Also, the addition of OMMT effectively improves the hot storage stability of the modified asphalt. The OMMT not only increases the compatibility between the WPE modifier and base asphalt but enhances the homogeneity of the modified asphalt at extreme temperatures. Heat capacity and phase behavior of modified asphalt after adding OMMT are changed; in the meantime, the thermal stability of the modified asphalt increases. J. VINYL ADDIT. TECHNOL., 21:89–93, 2015. © 2014 Society of Plastics Engineers

Effect of Organic Montmorillonite on the Cellular Structure and Mechanical Properties of POE/EVA/OMMT Nanocomposite Foams

Nanocomposite foams based-on ethylene octene copolymer (POE)/ethylene vinyl acetate (EVA) copolymer were prepared by melting of POE/EVA with organic montmorillonite (OMMT) by pressurized curing at high temperature. The cellular microstructure of the foamed samples was observed by scanning electron microscope. The effects of OMMT on the cellular structure and mechanical properties of the POE/EVA/OMMT nanocomposite foams were investigated. It was found that OMMT played an important role in affecting the microstructure. Comparing with POE/EVA foam the nanocomposite foams with the addition of 1-3 phr OMMT showed smaller cell size and the structure uniformity of foams was improved. The density of POE/EVA/OMMT nanocomposite samples was lower obviously, meanwhile the mechanical properties of the foamed samples was enhanced.

Toughening of ethylene-propylene random copolymer/clay nanocomposites: Comparison of different compatibilizers

Ethylene/propylene-random-copolymer (PPR)/clay nanocomposites were prepared by two-stage melt blending. Four types of compatibilizers, including an ethylene-octene copolymer grafted maleic anhydride (POE-g-MA) and three maleic-anhydride-grafted polypropylenes (PP-g-MA) with different melt flow indexes (MFI), were used to improve the dispersion of organic clay in matrix. On the other hand, the effects of organic montmorillonite (OMMT) content on the nanocomposite structure in terms of clay dispersion in PPR matrix, thermal behavior and tensile properties were also studied. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that the organic clay layers are mainly intercalated and partially exfoliated in the nanocomposites. Moreover, a PP-g-MA compatibilizer (compatibilizer B) having high MFI can greatly increase the interlayer spacing of the clay as compared with other compatibilizers. With the introduction of compatibilizer D (POE-g-MA), most of the clays are dispersed into the POE phase, and the shape of the dispersed OMMT appears elliptic, which differs from the strip of PP-g-MA. Compared with virgin PPR, the Young’s modulus of the nanocomposite evidently increases when a compatibilizer C (PP-g-MA) with medium MFI is used. For the nanocomposites with compatibilizer B and C, their crystallinities (X c) increase as compared with that of the virgin PPR. Furthermore, the increase of OMMT loadings presents little effect on the melt temperature (T m) of the PPR/OMMT nanocomposites, and slight effect on their crystallization temperature (T c). Only compatibilizer B can lead to a marked increases in crystallinity and T c of the nanocomposite when the OMMT content is 2 wt%.

Effect of organic montmorillonite on cold crystallization and hydrolytic degradation of poly(l-lactide)

The effect of organic montmorillonite (OMMT) on cold crystallization of poly(l-lactide) (PLLA) in different conditions including during the DSC heating process and during the annealing treatment was evaluated. The variations of crystalline structure of PLLA in different samples were comparatively investigated by using wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. The results show that OMMT exhibits an apparent nucleation effect for the cold crystallization of PLLA matrix. During the annealing treatment, the degree of crystallinity (Xc) increases with the increase of OMMT content. Specifically, the presence of OMMT leads to the formation of α΄-form crystallites. Study on the hydrolytic degradation behaviours of different samples shows that the hydrolytic degradation rate decreases with the increase of Xc, but it increases with the increase of OMMT content. The enhanced hydrophilicity and the formation of α΄-form crystallites are suggested to be the main reasons for the greatly improved hydrolytic degradation ability of samples which contain high content of OMMT. Furthermore, hydrolytic degradation also induces the change of microstructure of the samples. For pure PLLA, hydrolytic degradation promotes the increase of Xc. However, for PLLA/OMMT nanocomposites, hydrolytic degradation leads to the decrease of Xc and the degree of the decrease is dependent on the content of OMMT.

Dynamic rheology and morphology of polylactide/organic montmorillonite nanocomposites

AbstractThe effects of organic montmorillonite (OMMT) on the rheological behaviors and phase morphology of polylactide (PLA) were investigated. The rheological behaviors of nanocomposites showed mainly dependence on both temperature and OMMT content. At low OMMT loading (1 wt %), the complex viscosities showed a Newtonian plateau in low frequency region at low temperatures and converted to a shear‐thinning behaviors with increasing temperature. In comparison, at high OMMT loadings (above 5 wt %), strong shear‐thinning behaviors were observed in the full range of frequencies and temperatures. The results demonstrated rheology of PLA/OMMT is highly sensitive to the nanofillers filled materials. A pseudo‐solid‐like behavior at long scale time in the hybrids with OMMT loading was higher than 5 wt %, this response was related to the formation of a network structure across the polymer matrix due to strong interactions of PLA and OMMT that confined the relaxation process of the macromolecules. X‐ray diffraction and transmission electron microscopy indicated the nanocomposites at low OMMT loading were mainly exfoliated and intercalated nanocomposites were gradually formed with increasing OMMT loading. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011