scholarly journals Preparation and characterisation of modified reclaimed asphalt using nanoemulsion acrylate terpolymer

2019 ◽  
Vol 48 (5) ◽  
pp. 363-374 ◽  
Author(s):  
Abdelrahman Moukhtar Naser ◽  
Hamada Abd El - Wahab ◽  
Mohamed Abd El Fattah Moustafa El Nady ◽  
Abdelzaher E.A. Mostafa ◽  
Long Lin ◽  
...  
Keyword(s):  
Hot Mix Asphalt ◽  
Fourier Transforms ◽  
Thermo Gravimetric Analysis ◽  
Thermoplastic Elastomer ◽  
Warm Mix Asphalt ◽  
Gravimetric Analysis ◽  
Content Type ◽  
Reclaimed Asphalt ◽  
Asphalt Paving ◽  
Modified Binder

Purpose This paper aims to investigate the best methods of utilisation of reclaimed asphalt pavements (RAP) in Egypt, to determine the effect of using 100% RAP instead of using virgin aggregates and asphalt; investigate the effect of thermoplastic elastomer polymer as asphalt modifier; and also improve the mechanical and physical characteristics and consequently improving the quality of asphalt paving, increasing service life of asphalt-paving and reducing costs. Design/methodology/approach Nano acrylate terpolymers were prepared with different % (Wt.) of and were characterised by Fourier transforms infrared (FTIR), for molecular weight (Mw), by thermo gravimetric analysis (TGA) and by transmission electron microscopy (TEM). A 4% (Wt.) of the prepared nanoemulsion terpolymer was mixed with virgin asphalt as a polymer modifier, to improve and reuse of the RAP. The modified binder was tested. The tests conducted include penetration, kinematic viscosity, softening point and specific gravity. Application of Marshall mix design types; hot mix asphalt (HMA), warm mix asphalt (WMA) and cold in place recycled (CIR). Four different mix designs used; control mix contained virgin asphalt by HMA, and the other three mix designs were polymermodified asphalt sample by HMA, WMA and CIR. Findings The research results showed that using 4 Wt.% of the prepared nanoemulsion terpolymer to produce hot mix asphalt (HMA) and warm mix asphalt (WMA) achieved higher stability compared to the control mix and cold in place recycled (CIR). Research limitations/implications This paper discusses the preparation and the characterisation of nanoemulsion and its application in RAPs to enhance and improve the RAP quality. Practical implications Nano-acrylate terpolymer can be used as a new polymer to modify asphalt to achieve the required specifications for RAP. Originality/value According to the most recent surveys, Europe produced 265 tonnes of asphalt for road applications in 2014, while the amount of available RAP was more than 50 tonnes. The use of RAP in new blended mixes reduces the need of neat asphalt, making RAP recycling economically attractive.

Strength and microstructure characteristics of concrete with different grade exposed to standard fire

2020 ◽  
Vol 11 (3) ◽  
pp. 261-287
Author(s):  
Daniel Paul Thanaraj ◽  
Anand N. ◽  
Prince Arulraj
Keyword(s):  
Elevated Temperature ◽  
Residual Strength ◽  
Thermo Gravimetric Analysis ◽  
International Standards ◽  
Simple Relationship ◽  
Gravimetric Analysis ◽  
Content Type ◽  
Strength Grade ◽  
Standard Fire ◽  
Heated Concrete

Purpose The purpose of this study is to investigate the effect of standard fire on the strength and microstructure properties of concrete with different strength grades. Design/methodology/approach Different strength grades of concrete used for the investigation are M20, M30, M40 and M50. An electrical bogie hearth furnace was developed to simulate the International Standards Organization 834 standard fire curve.Concrete samples were subjected to high temperatures of 925, 1,029, 1,090 and 1,133°C for the duration of 1, 2, 3 and 4 h, respectively, as per standard fire curve. Compressive strength, tensile strength, thermal crack pattern and spalling of heated concrete specimens were evaluated by experimental investigation. Scanning electron microscopy and thermo-gravimetric analysis were performed to investigate the microstructure properties of heated concrete specimens. Findings Test results indicated reduction in the strength and changes in the microstructure properties of concrete exposed to elevated temperature. The degree of weight and the strength loss were found to be higher for concrete with higher grades. An empirical relation is proposed to determine the residual strength of concrete with different strength grade using regression analysis. Social implications Results of this research will be useful for the design engineers to understand the behavior of concrete exposed to elevated temperature as per standard fire. Originality/value When concrete is exposed to elevated temperature, its internal microstructure changes, thereby strength and durability of concrete deteriorates. The performance of concrete with different strength grade exposed to standard fire is well understood. This research’s findings will be useful for the designers to understand more about fire resistance of concrete. A simple relationship is proposed to determine the residual strength of concrete exposed to various durations of heating.

Synthesis, characterization and tribological behavior of oleic acid-capped core-shell lanthanum borate-SiO2 composites

2014 ◽  
Vol 66 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Zhengfeng Jia ◽  
Yan-qiu Xia ◽  
Xin Shao ◽  
San-ming Du
Keyword(s):  
Oleic Acid ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Thermo Gravimetric Analysis ◽  
Core Shell ◽  
Gravimetric Analysis ◽  
Content Type ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

Purpose – The purpose of this paper is to investigate the tribological properties of poly-alpha-olefin (PAO) with nano/microstructure core-shell lanthanum borate-SiO2 composites (OCLS). Design/methodology/approach – Oleic acid-capped core-shell lanthanum borate-SiO2 composites were synthesized by an easy way. The composites were characterized by means of Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and thermo gravimetric analysis (TGA). The friction and wear behaviors of the quenched AISI 1045 steel specimens sliding against AISI 52100 steel under the lubrication of PAO containing OCLS were comparatively investigated with PAO containing SiO2 additive on an Optimol SRV reciprocating friction and wear tester. On the other hand, the tribological properties of the PAO containing OCLS were also investigated on four-ball tester. Findings – The diameter of OCLS was about 20 nm, and the thickness of the SiO2 shell was less than 5 nm. The ratio of oleic acid (OA) is about 15 percent. The PAO containing OCLS possesses much better tribological properties than that of pure PAO and PAO containing SiO2 additive. Originality/value – The PAO+OCLS possess a better friction reducing and antiwear properties than pure PAO. The new additive can improve the tribological ability of machinery.

Cellulose nanocrystals reinforced shape memory polymer cardiovascular stent

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yu Chen ◽  
Irina Tatiana Garces ◽  
Tian Tang ◽  
Cagri Ayranci
Keyword(s):  
Additive Manufacturing ◽  
Shape Memory ◽  
Thermo Gravimetric Analysis ◽  
Modulated Dsc ◽  
Recovery Ratio ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Ratio Measurement ◽  
Content Type

Purpose The purpose of this paper is to demonstrate an innovative, fast and low-cost method to fabricate customized stents using polyurethane-based shape memory polymers composite reinforced by cellulose nanocrystal (CNC), achieved by a commercial desktop extrusion-based additive manufacturing (EBAM) device. Design/methodology/approach The composite filament for printing the stents was prepared by a two-step melt-compounding extrusion process. Afterward, the stents were produced by a desktop EBAM printer. Thermal characterizations, including thermo-gravimetric analysis (TGA) and modulated differential scanning calorimetry (modulated DSC), were conducted on stent samples and filament samples, respectively. Then the stents were programmed under 45°C. Recovery characterizations, including recovery force and recovery ratio measurement, were conducted under 40°C. Findings TGA results showed that the materials were stable under the printing temperature. Modulated DSC results indicated that, with the addition of CNCs, the glass transition temperature of the material dropped slightly from 39.7°C at 0 Wt.% CNC to 34.2°C at 7 Wt.% CNC. The recovery characterization showed that the stents can exert a maximum recovery force of 0.4 N/mm when 7 Wt.% of CNCs were added and the maximum recovery ratio of 35.8% ± 5.1% was found when 4 Wt.% of CNCs were added. The addition of CNC improved both the recovery ratio and the recovery force of the as-prepared stents. Originality/value In terms of recovery force, the as-prepared stents out-performed commercially available stents by 30 times. In addition, additive manufacturing offers more flexibility in the design and fabrication of customized cardiovascular stents.

scholarly journals New water-based flexographic ink based on new ter-polymer nano-particles as eco-friendly binders – Part II

2020 ◽  
Vol 49 (6) ◽  
pp. 473-482
Author(s):  
H. Abd El-Wahab ◽  
G.A. Meligi ◽  
M.G. Hassaan ◽  
L. Lin
Keyword(s):  
Water Resistance ◽  
Low Cost ◽  
Thermo Gravimetric Analysis ◽  
Gel Permeation Chromatography ◽  
Nano Particles ◽  
Gravimetric Analysis ◽  
Adhesion Properties ◽  
Content Type ◽  
Low Viscosity ◽  
Water Based

Purpose The purpose of this study is to prepare, characterise and evaluate nano-emulsions of ter-polymers of various compositions as eco-friendly binders for flexographic ink industry. Design/methodology/approach Various nano-emulsions of ter-polymers were prepared based on Vinyl acetate, Vinyl Versatate, butyl acrylate, acrylic acid and acrylamide monomers by means of a conventional seeded emulsion polymerisation technique, using K2S2O8 as the initiator. The characterisation of the prepared emulsions was performed using Fourier transform infrared, thermo-gravimetric analysis, gel permeation chromatography and transmission electron microscopy. A selection of co-polymers and ter-polymers were formulated with pigments and additional ingredients, as water-based flexographic inks. The inks were characterised for their rheological properties, pH, degree of dispersion, water-resistance and colour density. Findings It was found that the low viscosity of the prepared polymers may reduce the film thickness of the flexographic inks and may also increase the spreading of the ink on the surface. As a result, stable modified poly acrylate-based latex with improved physico-mechanical properties was obtained. The prepared latexes showed improved properties such as enhanced thermal stability and better water resistance. The effect of the emulsifier type on the properties of the resulting emulsion latexes and their corresponding films were investigated. Also, as the hydrophobic monomer increases, so does the colour density and increasing the binder ratio enhances the gloss values. The improving in gloss values were obtained and provide excellent adhesion properties for both the pigment particles and the base paper. Research limitations/implications The study focusses on the preparation of new water-based ter-polymer nano-particles and their use as eco-friendly binders for flexographic ink industry. Ink formulations based on other different type emulsion polymers could also be studied to assess the applicability of the ink formulation system found for other binders. Practical implications The ink formulations developed could find use in industrial-scale printing. Originality/value Eco-friendly environment and low-cost ink formulations for printing on paper substrates are novel.

Nacre-mimetic CH/MMT fabrication coating on PET fabric for improving anti-dripping performance

2020 ◽  
Vol 32 (6) ◽  
pp. 803-812
Author(s):  
Yinchun Fang ◽  
Xinhua Liu ◽  
Wenqing Fei
Keyword(s):  
Flame Retardant ◽  
Flame Retardancy ◽  
Thermo Gravimetric Analysis ◽  
Original Research ◽  
Gravimetric Analysis ◽  
Experimental Basis ◽  
Limiting Oxygen Index ◽  
Content Type ◽  
Pet Fabric ◽  
Assembly Method

PurposePET fiber is widely used in many fields, such as clothing and decorative materials. However, the high flammability and dripping problem restrict its applications. It is vital for PET fiber to overcome these two main drawbacks for practical applications.Design/methodology/approachIn this paper nacre-mimetic flame retardant coating of chitosan (CH) and Montmorillonite (MMT) was fabricated on PET fabrics through the layer-by-layer assembly method. The flame retardancy and anti-dripping performance of the treated PET fabric were investigated.FindingsThe results of limiting oxygen index (LOI) value and vertical burning test revealed the anti-dripping performance of PET fabrics which was greatly improved, while the flame retardancy has not been improved. The dripping phenomena was eliminated when the CH/MMT bilayers were over 5 BL. Thermo gravimetric analysis (TGA) results revealed that nacre-mimetic coated CH/MMT bilayers on PET fabrics would promote the char formation both under nitrogen atmosphere and under air atmosphere indicating the obviously condensed phase flame retardant action. scanning electron microscopy (SEM) images of the char residues revealed that coated PET fabrics would promote the formation of char.Research limitations/implicationsHowever, the char was an unstable char which would further combust to change the thermal degradation and combustion process of PET fabric. Though PET fabric coated by this CH/MMT nacre-mimetic system had no flame retardancy, the anti-dripping performance was greatly improved. This research would provide experimental basis for improving the anti-dripping performance for thermoplastic materials.Originality/valueThis research is the original research for the flame retardant treatment by fabrication nacre-mimetic CH/MMT coating on PET fabric, which has not been reported previously. This research would provide experimental basis for improving the anti-dripping performance for thermoplastic polymer fabrics.

Tribological behaviours of surface-modified serpentine powder as lubricant additive

2016 ◽  
Vol 68 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Yawen Zhang ◽  
Zhipeng Li ◽  
Jincan Yan ◽  
Tianhui Ren ◽  
Yidong Zhao
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Lubricant Additives ◽  
Aliphatic Acid ◽  
Gravimetric Analysis ◽  
Edge Structure ◽  
Content Type ◽  
X Ray ◽  
Grafting Ratio ◽  
Surface Modified ◽  
X Ray Absorption

Purpose – The aim of this paper is to study the tribological performance and self-repairing performance of surface-modified nanoscale serpentine powders as lubricant additives in the mineral base oil (5-CST). Design/methodology/approach – Fourier transform infrared spectroscopy spectra and thermo-gravimetric analysis of both modified and unmodified serpentine were performed to analyse their grafting ratio and suspension after modified using a long-chain naphthene aliphatic acid. The tribological properties of surface-modified serpentine as lubricant additives in 5-CST were evaluated and the worn surfaces were investigated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). Findings – The results show that the serpentine particles have high grafting ratio, improving the dispersity in 5-CST. When the serpentine concentration of 1.00 weight per cent is used as additives in 5-CST, friction coefficient reduces by 14.80 per cent under 294 N and wear scar diameter (WSD) decreases by 11.82 per cent. The results of X-ray absorption near edge structure and XANES show that the adsorption and tribochemical reactions occur to form self-repairing lubrication films. Originality/value – The paper illustrates a tribofilm form on the rubbed surface, which is responsible for the decrease in friction and wear, mainly containing iron oxides, silicon oxides, magnesium oxides and organic compounds. The results are useful for further applications in advanced environmental friendly lubricating oils and additives.

Research on Application of Warm Mix Asphalt Technology in Central Plant Hot Recycled Engineering

2013 ◽  
Vol 361-363 ◽  
pp. 1635-1639
Author(s):  
Qing Zhou Wang ◽  
Shu Yan Liu ◽  
Xiao Li Li
Keyword(s):  
Hot Mix Asphalt ◽  
Asphalt Mixture ◽  
Warm Mix Asphalt ◽  
Reclaimed Asphalt Pavement ◽  
Performance Tests ◽  
Recycled Asphalt ◽  
Reclaimed Asphalt ◽  
Central Plant ◽  
Research On Application

The warm mix asphalt technology was introduced to breaks through the low reclaimed asphalt pavement (RAP) ratio in central plant hot recycled engineering. Firstly, performance tests for traditional hot mix asphalt and central plant warm recycled asphalt mixture with different RAP ratios (0%,40%,50%,70%,100%) were conducted. It was concluded that the performance of warm mix asphalt was as good as hot mix asphalt, and the RAP ratio could increase to 60% by central plant warm recycling technology. Then a practical central plant warm recycled engineering with RAP ratio 50% was analyzed. It was concluded that not only the performance of the recycled asphalt mixture met the standard requirements absolutely, but also the compaction quality of the recycled pavement was improved.

Preparation and performance evaluation of mPAO8 using olefin from coal as raw material

2017 ◽  
Vol 69 (5) ◽  
pp. 678-682 ◽  
Author(s):  
Yuefeng Ma ◽  
Jian Xu ◽  
Xiangqiong Zeng ◽  
Haizhen Jiang ◽  
Jiusheng Li
Keyword(s):  
Thermal Stability ◽  
Oxidative Stability ◽  
Thermo Gravimetric Analysis ◽  
Viscosity Index ◽  
Oxidation Stability ◽  
Molecular Structures ◽  
Resonance Spectroscopy ◽  
Gravimetric Analysis ◽  
Content Type ◽  
Base Oil

Purpose The purpose of this paper is to prepare metallocene polyalphaolefin 8 (mPAO8) by the oligomerization of olefin from coal with metallocene catalyst system and compare it with commercially available polyalphaolefin 8 (PAO8) from Chevron. Design/methodology/approach Molecular structures, component and mass were determined by nuclear magnetic resonance spectroscopy, gas chromatography and gel permeation chromatography, respectively. The physico-chemical properties, including Noack volatility, viscosity index and elemental analyses, were studied. The oxidative stability was evaluated by pressurized differential scanning calorimetry, whereas the thermal stability was studied by thermo-gravimetric analysis. Findings The produced mPAO8 consisted of a large part of tetramer, pentamer and a small part of trimer and hexamer. Additive T501 significantly improved the oxidation stability of PAO8 from Chevron and the synthesized mPAO8. Both samples had similar properties, such as oxidative stability, additive response, pour point and Noack volatility loss. But mPAO8 possessed a higher thermal stability, better viscosity index and flash point than PAO8. Therefore, the mPAO8 prepared by the oligomerization of olefin from coal could be used as base oil for lubricant development. Originality/value The mPAO8 base oil was successfully prepared by successive carbon numbers and shows similar properties with commercially available PAO8 products from Chevron. The findings can cover the shortage of the synthesis lubricants market in China.

scholarly journals Use of Plastic Wastes and Reclaimed Asphalt for Sustainable Development

2020 ◽  
Vol 15 (2) ◽  
pp. 182-196
Author(s):  
Umar Hayat ◽  
Abdur Rahim ◽  
Ammad Hassan Khan ◽  
Zia Ur Rehman
Keyword(s):  
Polyethylene Terephthalate ◽  
Asphalt Pavement ◽  
Reclaimed Asphalt Pavement ◽  
Gravimetric Analysis ◽  
Reclaimed Asphalt ◽  
Air Voids ◽  
Plastic Wastes ◽  
The Face ◽  
Modified Binder ◽  
Marshall Stability

The increased cost of virgin material, declining resources and increasing plastic wastes have turned the research momentum towards sustainable and green pavements. Reclaimed Asphalt Pavement (RAP) from the construction industry and plastic wastes disposal is the main problem for Pakistan as well as other developing countries in the face of fewer funds for the construction, repair, and rehabilitation of the extensive road network. In this research, the attempt has been made to study the use of Reclaimed Asphalt Pavement and plastic wastes to counter these issues. Virgin binder was modified with three different contents (2%, 4%, and 6%) of Polyethylene Terephthalate and three contents (20%, 30%, and 40%) of Reclaimed Asphalt Pavement. Conventional properties of the modified binder were determined by penetration and softening point. At the same time, thermal stability was checked by Thermal Gravimetric Analysis, and resistance against rutting was evaluated with the help of Dynamic Shear Rheometer. It is observed that modified binder remains stable up to a temperature of 470 °C and showed improved resistance against rutting. Marshall mix properties were determined and compared to specifications of the National Highway Authority of Pakistan. Optimum Marshall stability was observed with 4% Polyethylene Terephthalate, and 30% Reclaimed Asphalt Pavement, while flow and air voids remained in limits. As per the results, utilisation of plastic wastes in asphalt pavements enhances the performance and helps to reduce the environmental pollution and landfill problems due to Reclaimed Asphalt Pavement and plastic wastes.

Sign in / Sign up

Export Citation Format

Share Document