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.

Synthesis of Formaldehyde Free Amino Resin to Produce Green Eco-Labelled Leather with Improved Retanning Properties

2020 ◽  
Vol 115 (4) ◽  
pp. 132-139
Author(s):  
Muhammad Naveed Ashraf ◽  
Shahzad Maqsood Khan ◽  
Shahid Munir ◽  
Rashid Saleem
Keyword(s):  
Thermal Stability ◽  
Water Solubility ◽  
Thermo Gravimetric Analysis ◽  
Sulfanilic Acid ◽  
Gravimetric Analysis ◽  
Melamine Resin ◽  
Organoleptic Properties ◽  
Formaldehyde Content ◽  
Leather Processing ◽  
Percentage Efficiency

Formaldehyde has many applications in the chemical industry including synthesis of amino resins which are used in leather processing. After application in leather, these resins are hydrolyzed under certain conditions to release free formaldehyde which has high environmental concerns due to its proven carcinogenic effects. The objective of this work is to develop a formaldehyde free melamine-based resin to produce green leather with improved retanning properties and thermal stability. The optimum melamine resin was synthesized by condensing melamine with glyoxal instead of formaldehyde. Further, the water solubility and improved thermal stability of synthesized melamine resins were achieved by introduction of sulfanilic acid in resin structure. Synthesized resin was used in leather retanning in comparison with commercially available melamine resin as a control. Both leathers were tested for mechanical properties, organoleptic properties, grain surface and fiber structure analysis. Comparative free formaldehyde content was measured in resultant leathers. Effluents of retanning baths were comparatively analyzed. Optimum resin was also characterized by thermo gravimetric analysis and FTIR. The results of this study showed that the experimental resin has imparted significant improvement in mechanical and organoleptic properties of leather as compared to the control resin. Analysis of free formaldehyde content confirmed the absence of free formaldehyde in leather treated with optimum resin while 141 mg/kg formaldehyde was detected in leather treated with control resin. Free formaldehyde was also absent in effluent of experimental resin while 305 mg/kg formaldehyde was detected in effluent of control resin. Moreover, percentage efficiency in COD, TDS and TSS load of effluent was observed as 9.62, 7.2 and 6.31 respectively.  Resultant leather was free from formaldehyde making it safe for human along with reduction in pollution load of tannery.  

Enhancement of Thermo-Oxidative Stability of Vegetable Oil Based Lubricant via Chemical Modification Techniques

2015 ◽  
Vol 813-814 ◽  
pp. 695-699
Author(s):  
S. Arumugam ◽  
G. Sriram ◽  
A. Hemanth Sai Kumar Chowdary ◽  
Janga Subramanya Sai
Keyword(s):  
Chemical Modification ◽  
Oxidative Stability ◽  
Vegetable Oils ◽  
Rapeseed Oil ◽  
Chemical Structure ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Transesterification Method ◽  
Unique Chemical

The rising demand for environmentally acceptable lubricant has led researchers to look to vegetable oils as an alternative to petroleum based lubricants. Vegetable oils have radically distinctive properties owing to their unique chemical structure which have greater ability to lubricate and have higher biodegradability. In spite of advantages, they are limited to inadequate thermo-oxidative stability and poor low-temperature properties which hinder their utilization. In the present study in order to produce a bio lubricant with good thermo-oxidative stability, rapeseed oil was subjected to two different chemical modification techniques viz., epoxidation method and successive transesterification method. The thermo-oxidative stability of formulated oil was analysed using Thermo Gravimetric Analysis (TGA). TGA analysis divulges that the thermo-oxidative stability of rapeseed oil was greatly improved with the epoxidation method in comparison with the successive transesterification method.

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.

Effect of Alkali and Silane Treatment on the Thermal Stability of Hemp Fibers as Reinforcement in Composite Structures

2011 ◽  
Vol 415-417 ◽  
pp. 666-670 ◽  
Author(s):  
Na Lu ◽  
Shubhashini Oza ◽  
Ian Ferguson
Keyword(s):  
Thermal Stability ◽  
Composite Structures ◽  
Natural Fiber ◽  
Alkali Treatment ◽  
Thermo Gravimetric Analysis ◽  
Natural Fibers ◽  
Gravimetric Analysis ◽  
Silane Treatment ◽  
Hemp Fibers ◽  
Thermal Stability Of

Natural fiber reinforced composites are being used as reinforcement material in composite system due to their positive environmental benefits. Added to that, natural fibers offer advantages such as low density, low cost, good toughness, high specific strength, relatively non-abrasive and wide availability. However, the low thermal stability of natural fibers is one of the major challenges to increase their use as reinforcing component. In this study, a thorough investigation has been done to compare the effect of two chemical treatment methods on the thermal stability of hemp fibers. 5wt% sodium hydroxide and 5wt% triethoxyvinylsilane was used for the treatment of hemp fibers. Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis were used for characterization of untreated and treated fiber. The results indicated that 24 hours alkali treatment and 3 hours silane treatment time enhanced the thermal stability of the hemp fiber. However, alkali treatment shows better improvement compared to silane treatment.

Effect of boron-nitrogen modified soybean oil additive on biodegradability, anti-oxidation property, and lubricity of rapeseed oil

2019 ◽  
Vol 234 (2) ◽  
pp. 282-291 ◽  
Author(s):  
Ping Liu ◽  
Xin Wang ◽  
Jiang Wu ◽  
Wang Lin ◽  
Yanhan Feng ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Soybean Oil ◽  
Rapeseed Oil ◽  
Energy Dispersive Spectrometer ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Modified Soybean Oil ◽  
Wear And Friction ◽  
Friction Reducing ◽  
Boron Nitrogen

Two novel boron-nitrogen modified soybean oil additives with different length of chain structures (abbreviated as BNS1 and BNS2) were synthesized. The thermal stability of BNS1 and BNS2 was evaluated by thermo-gravimetric analysis. The effect of the as-synthesized additives on the biodegradability, anti-oxidation property, and lubricity in rapeseed oil was evaluated by respective standard method. Moreover, the morphology and tribochemical characteristics of the worn surfaces were examined by scanning electron microscope assembled with energy dispersive spectrometer. The results indicated that BNS1 and BNS2 both possess good thermal stability; BNS1 slightly impairs the biodegradability of rapeseed oil, but BNS2 facilitates the biodegradability of rapeseed oil. BNS1 and BNS2 could improve the anti-wear and friction-reducing performance of the rapeseed oil, but BNS1 exhibited better anti-wear ability as compared to that of BNS2, BNS2 exhibited better anti-wear ability in reducing friction coefficients as compared to that of BNS1. The enhanced anti-wear and friction-reducing abilities of rapeseed oil were ascribed to the formation of a composite boundary lubrication film due to the strong adsorption of BNS1 or BNS2 and rapeseed oil onto the lubricated surfaces and their tribochemical reactions with metal surfaces. BNS1 and BNS2 could both facilitate the anti-oxidation properties of the rapeseed oil.

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.

Palm Kernel Shell Filled Recycled High-Density Polyethylene: Effect of Filler Loading

2016 ◽  
Vol 857 ◽  
pp. 191-195 ◽  
Author(s):  
A. Nadiatul Husna ◽  
Bee Ying Lim ◽  
H. Salmah ◽  
Chun Hong Voon
Keyword(s):  
Thermal Stability ◽  
High Density Polyethylene ◽  
Thermo Gravimetric Analysis ◽  
Palm Kernel ◽  
Filler Loading ◽  
High Density ◽  
Gravimetric Analysis ◽  
Melt Mixing ◽  
Palm Kernel Shell ◽  
Thermal Stability Of

Palm kernel shells (PKS) filled recycled high density polyethylene (rHDPE) biocomposites were produced using melt mixing. The biocomposites were prepared on Brabender Plasticorder at temperature of 185 °C and rotor speed of 50 rpm by varying filler loading (0 to 40 phr). In this study, the effect of PKS loading on rheological properties and thermal stability of rHDPE/PKS were investigated. Rheological study of the biocomposites was carried out by means of capillary rheometer under temperature of 190 °C, 200 °C and 210 °C. Thermal properties of biocomposites were studied by using thermo gravimetric analysis (TGA). The rheological results showed that the flowability of the composite increased with increasing temperature. Meanwhile, the result of TGA showed that at higher PKS loading, rHDPE/PKS biocomposites had lower total weight loss. The thermal stability of the biocomposites was reduced due to the addition of filler loading.

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.

Study on the thermal stability of Controlled Permeability Formwork

2011 ◽  
Vol 374-377 ◽  
pp. 1426-1429
Author(s):  
Xiao Meng Guo ◽  
Jian Qiang Li ◽  
Xian Sen Zeng ◽  
De Dao Hong
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Dynamic Mechanical Analysis ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Construction Work ◽  
Thermo Gravimetric ◽  
Excellent Thermal Stability ◽  
Thermal Stability Of

In this study, the thermal properties of a kind of new geotextile materials, so called controlled permeable formwork (CPF), were studied. Thermo-gravimetric analysis showed that the weight of CPF didn’t change much between 0~350 °C. Dynamic mechanical analysis showed that the storage modulus of CPF reduced from 25 MPa to around 10 MPa when the temperature rose to above 100 °C. The strength of sample decreased slightly with the increase of the temperature. The breaking elongation changed slightly with a maximum at 80 °C. The CPF showed excellent thermal stability and was suitable for general use in construction work.

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.

Sign in / Sign up

Export Citation Format

Share Document