Chemical and Thermal Characterization of Road Bitumen Ageing

2010 ◽  
Vol 636-637 ◽  
pp. 273-279 ◽  
Author(s):  
M. Sá da Costa ◽  
Fabienne Farcas ◽  
L.F. Santos ◽  
M.I. Eusébio ◽  
António Correia Diogo

Bitumen ageing stands for a number of physico-chemical modifications that occur in bitumen as a response to environmental conditions. Several tests have been proposed to simulate bitumen ageing. Two of the most common ones are: a) the Rolling Thin Film Oven Test (RTFOT), which simulates short term ageing; b) the Pressure Ageing Vessel (PAV) test, which accounts for long-term ageing and it is usually performed on the RTFOT residue. A study of the physico-chemical modifications of a 50/70 pavement grade bitumen caused by ageing is presented. Both RTFOT and PAV tests were used. A follow-up of bitumen modifications due to ageing was done by several methods. In particular: 1) Fourier transform infrared spectroscopy (FTIR), to follow bitumen oxidation by the increase of oxygenated functional groups, which were quantified by taking appropriate structural indices; 2) Iatroscan thin layer chromatography (TLC), to follow bitumen composition expressed by the generic SARA fractions (saturates, aromatics, resins and asphaltenes); 3) Gel permeation chromatography (GPC), under “ultra-fast” conditions, to follow the colloidal structure of bitumen; and 4) Differential scanning calorimetry (DSC), to evaluate the changes of the crystallized fractions (%FC) and the glass relaxation temperature (Tg). The results show that the PAV test causes more severe changes in bitumen than the RTFOT test. In particular, the evolution of the oxidation processes could be quantified by taking carbonyl and sulfoxide structural indices. Ageing also modified the SARA profile, namely, the relative contribution of aromatics, resins and asphaltenes fractions. On the other hand, DSC data remained almost unaffected after ageing tests, which may be indicative of the survival of most of the phases of the bitumen after these tests. Finally, a comparative analysis of the sensitivity and performance of all these methods is presented.

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Emerson C. G. Campos ◽  
Cristiano Zanlorenzi ◽  
Bruno F. Nowacki ◽  
Gabriela M. Miranda ◽  
Denis A. Turchetti ◽  
...  

This work reports the synthesis and characterization of a conjugated polymer based on fluorene and terpyridine, namely, poly[(9,9-bis(3-((S)-2-methylbutylpropanoate))fluorene-alt-6,6′-(2,2′:6′,2′′-terpyridin-6-yl)] (LaPPS71). The structure was characterized by 1H and 13C nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR) spectroscopy. The molar mass was measured by gel permeation chromatography (GPC). As thermal characterization, the glass transition temperature (Tg) was measured by differential scanning calorimetry (DSC). The polymer structure contains two sites capable of complexation with metallic ions, affording the possibility of obtainment of independent or electronically coupled properties, depending on the complexation site. The photophysical properties were fully explored in solution and solid state, presenting ideal results for the preparation of various metallopolymers, in addition to potential application as a metamaterial, due to the presence of the chiral center in the side chains of the polymer.


2016 ◽  
Vol 36 (2) ◽  
pp. 189-197
Author(s):  
Gabriela Jandikova ◽  
Pavel Kucharczyk ◽  
Norbert Miskolczi ◽  
Alena Pavelkova ◽  
Adriana Kovalcik ◽  
...  

Abstract This work is dedicated to polyester urethane (PEU)-based biocomposites, with special focus placed on techniques for compatibilisation to heighten interfacial adhesion between the PEU matrix and flax fibres. Tests were conducted on the effects of modification so as to increase interfacial adhesion between the flax fibres and the polyester matrix. These tests involved a commercial silane-based compatibilising additive, two experimentally synthesised agents, oleic acid (OA) and di-tert-butyl peroxide (DTBP). Furthermore, the flax fibres underwent acid or alkali treatment. The biocomposites were characterised by gel permeation chromatography, infrared spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Mechanical properties were investigated through tensile testing. Biocomposites with a commercial silane-based additive and synthesised agent, based on maleic-anhydride, were assessed as the best solution. Nevertheless, all modifications, excluding alkali treatment of fibres, significantly increased the performance of the material.


2014 ◽  
Vol 50 (4) ◽  
pp. 713-725 ◽  
Author(s):  
Sudarshan Singh ◽  
Sunil B. Bothara

Mucilage was isolated from the seeds of Diospyros melonoxylonRoxb., a plant growing naturally in the forests of India. Various physico-chemical methods like particle analysis, scanning electron microscopy, differential scanning calorimetry, differential thermal analysis, thermogravimetry analysis, molecular weight by gel permeation chromatography, rheometry, elemental analysis, x-ray diffraction spectrometry, zeta potential, fourier transform infrared spectroscopy, 1D(1H and 13C) (NMR) have been employed to characterize this gum in the present study. Particle analyses suggest that mucilage had particle size in nanometer. SEM analysis suggested that the mucilage had irregular particle size. The glass transition temperature of the gum observed was 78 °C and 74 °C by DSC and DTA respectively. The Thermogravimetry analysis suggested that mucilage had good thermal stability with two stage decomposition. The molecular weight of mucilage was determined to be 8760, by gel permeation chromatography, while the viscosity of mucilage was observed to be 219.1 cP. The XRD pattern of the mucilage indicated a complete amorphous nature. Elemental analysis of the gum revealed specific contents of carbon, hydrogen, nitrogen and sulfur. The major functional groups identified from FT-IR spectrum include 3441 cm-1 (-OH), 1632 cm-1 (-COO-), 1414 cm-1 (-COO-) and 1219 cm-1 (-CH3CO). Analysis of mucilage by paper chromatography and 1D NMR indicated the presence of sugars.


2021 ◽  
pp. 108-108
Author(s):  
Chetana Deoghare ◽  
Shruti Balaji ◽  
Savitha Dhandapani ◽  
Honey Srivastava ◽  
Anasuya Ganguly ◽  
...  

This paper reports the synthesis and characterization of monomers itaconic anhydride (IA) and tri-O-acetyl-D-glucal (TAG) as well as 4,6-di-O-acetyl-D-glucal (PSG). The homopolymers and copolymers of IA and TAG were synthesized via free radical copolymerization in bulk using azobisiso-butyronitrile as an initiator using different feed ratios of monomers. Their structural, molecular, and thermal characterization was done using 1H-NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry, respectively. The glass transition temperature (Tg) of copolymers was found in the range of 139-145 ?C. The highest Tg was found for IA-TAG2 copolymers, whereas IA-TAG4 copolymer showed lowest Tg. The molecular weight of the copolymers was in the range 5157-5499 g mol-1. The monomer TAG undergoes Ferrier rearrangement in water to give PSG. The antimicrobial activity of IA, TAG, PSG and IA-TAG copolymers was studied using the minimum microbicidal concentration-broth dilution method. TAG, IA, and PSG, as well as homopolymer and copolymers of IA and TAG are excellent antimicrobial agents.


2005 ◽  
Vol 480-481 ◽  
pp. 257-268 ◽  
Author(s):  
L. De Bartolo ◽  
A. Gugliuzza ◽  
S. Morelli ◽  
B. Cirillo ◽  
A. Gordano ◽  
...  

The aim of this work was the exploration of a potential biocompatible membrane prepared from a modified polyetheretherketone (PEEK-WC). The physico-chemical properties of PEEK-WC were characterised by Differential Scanning Calorimetry and FT-Infrared Spectroscopy. The surface affinity of this membrane to human plasma and proteins such as albumin, fibrinogen and immunoglobulins G was evaluated and compared with that of commercial membranes. The wettability of all investigated membranes was established by water contact angle measurements. PEEK-WC membranes exhibited moderate wettability and low protein adsorption, differently from other commercial membranes such as cellulose acetate membrane. A preferential adsorption of hydrophilic proteins as albumin on the membrane surfaces was observed. Human plasma adsorption on membranes followed the same trend as individual protein solutions.


2020 ◽  
Vol 16 (5) ◽  
pp. 685-707 ◽  
Author(s):  
Amna Batool ◽  
Farid Menaa ◽  
Bushra Uzair ◽  
Barkat Ali Khan ◽  
Bouzid Menaa

: The pace at which nanotheranostic technology for human disease is evolving has accelerated exponentially over the past five years. Nanotechnology is committed to utilizing the intrinsic properties of materials and structures at submicroscopic-scale measures. Indeed, there is generally a profound influence of reducing physical dimensions of particulates and devices on their physico-chemical characteristics, biological properties, and performance. The exploration of nature’s components to work effectively as nanoscaffolds or nanodevices represents a tremendous and growing interest in medicine for various applications (e.g., biosensing, tunable control and targeted drug release, tissue engineering). Several nanotheranostic approaches (i.e., diagnostic plus therapeutic using nanoscale) conferring unique features are constantly progressing and overcoming all the limitations of conventional medicines including specificity, efficacy, solubility, sensitivity, biodegradability, biocompatibility, stability, interactions at subcellular levels. : This review introduces two major aspects of nanotechnology as an innovative and challenging theranostic strategy or solution: (i) the most intriguing (bare and functionalized) nanomaterials with their respective advantages and drawbacks; (ii) the current and promising multifunctional “smart” nanodevices.


2019 ◽  
pp. 089270571987822
Author(s):  
Saud Aldajah ◽  
Mohammad Y Al-Haik ◽  
Waseem Siddique ◽  
Mohammad M Kabir ◽  
Yousef Haik

This study reveals the enhancement of mechanical and thermal properties of maleic anhydride-grafted polypropylene (PP- g-MA) with the addition of nanocrystalline cellulose (NCC). A nanocomposite was manufactured by blending various percentages of PP, MA, and NCC nanoparticles by means of a twin-screw extruder. The influence of varying the percentages of NCC on the mechanical and thermal behavior of the nanocomposite was studied by performing three-point bending, nanoindentation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy tests. The novelty of this study stems on the NCC nanoparticles and their ability to enhance the mechanical and thermal properties of PP. Three-point bending and nanoindentation tests revealed improvement in the mechanical properties in terms of strength, modulus, and hardness of the PP- g-MA nanocomposites as the addition of NCC increased. SEM showed homogeneity between the mixtures which proved the presence of interfacial adhesion between the PP- g-MA incorporated with NCC nanoparticles that was confirmed by the FTIR results. DSC and TGA measurements showed that the thermal stability of the nanocomposites was not compromised due to the addition of the coupling agent and reinforced nanoparticles.


Author(s):  
Ignazio Blanco ◽  
Traian Zaharescu

AbstractA series of ethylene-propylene-diene-terpolymer (EPDM)/polyhedral oligomeric silsesquioxane (POSS) composites at different percentage of POSS were prepared and subjected to γ-irradiation. Both irradiated and non-irradiated EPDM and composites were investigated by the means of thermal analysis to verify if the presence of POSS molecules is able to reduce the oxidation level of free radicals generated during the degradation and to evaluate the effects of the irradiation. EPDM composites at 1, 3 and 5 mass% of POSS were thus degraded in a thermogravimetric (TG) balance in dynamic heating conditions (25–700 °C), in both inert and oxidative atmosphere by flowing nitrogen and air respectively. Thermal characterization was then completed by carrying out Differential Scanning Calorimetry (DSC) analysis from sub-ambient to better highlight the melting of the polymer and polymer composites occurring just above the room temperature. FTIR spectroscopy was also performed for the prepared samples to check the presence of the molecular filler in the composites and for the TG’s residue at 700 °C, in order to evaluate its nature. DSC and TGA parameters were detected and discussed to have information about the effect of the degradation’s environment, the effect of irradiation on polymer stabilization and the effect of POSS content in the polymer matrix.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Deshraj Singh ◽  
Pawan Kumar ◽  
Jitendra Singh ◽  
Dharm Veer ◽  
Aravind Kumar ◽  
...  

AbstractComposites proton conducting material based on cesium dihydrogen phosphate (CDP) doped with zirconium oxide (1−x) CsH2PO4/x ZrO2 were synthesized with different concentration having in the range such as x = 0.1, 0.2, 0.3 and 0.4 by ball milling method. The prepared solid acid composites were dried at 150 °C for 6 h. Structural and thermal characterization of solid acid composite proton electrolytes were carried out by X-ray diffractometer, Fourier transform infrared spectroscopy, and Raman spectroscopy respectively. Phase transition of the prepared materials was carried out by using differential scanning calorimetry and conductivity was measured by LC Impedance meter in the range 1 Hz to 400 kHz. The ionic conductivity of ZrO2 doped CsH2PO4 (CDP) was increased up to 1.3 × 10–2 S cm−1 at the 280 °C under environment atmospheric humidification which showed high stability as compared to pure CsH2PO4 (CDP). This obtaining result would be useful for establishing and design the next generation fuel cell.


Author(s):  
Georgina Alejandra Venegas-Cervera ◽  
Andrés Iván Oliva ◽  
Alejandro Avila-Ortega ◽  
José Manuel Cervantes-Uc ◽  
Leydi Maribel Carrillo-Cocom ◽  
...  

AbstractElectrospun polymers are an example of multi-functional biomaterials that improve the material-cellular interaction and aimed at enhancing wound healing. The main objective of this work is to fabricate electrospun polyurethane membranes using arginine as chain extender (PUUR) in order to test the fibroblasts affinity and adhesion on the material and the polymer toxicity. Polyurethane membranes were prepared in two steps: (i) the polyurethane synthesis, and ii) the electrospinning process. The membranes were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy, gel permeation chromatography, and differential scanning calorimetry techniques. The evaluation of PUUR as a scaffolding biomaterial for growing and developing of cells on the material was realized by LIVE/DEAD staining. The results show that the fluorescent surface area of human fibroblasts (hFB), was greater in control dense membranes made from Tecoflex than in electrospun and dense PUUR. From SEM analysis, the electrospun membranes show relatively uniform attachment of cells with a well-spread shape, while Tecoflex dense membranes show a non-proliferating round shape, which is attributed to the fiber’s structure in electrospun membranes. The cell morphology and the cell attachment assay results reveal the well spreading of hFB cells on the surface of electrospun PUUR membranes which indicates a good response related to cell adhesion.


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