scholarly journals Glass transitions in bituminous binders

2021 ◽  
Vol 54 (3) ◽  
Author(s):  
Panos Apostolidis ◽  
Michael Elwardany ◽  
Laurent Porot ◽  
Stefan Vansteenkiste ◽  
Emmanuel Chailleux
Keyword(s):  
Low Temperatures ◽  
Positive Influence ◽  
Temperature Modulation ◽  
Relaxation Phenomena ◽  
Glass Transitions ◽  
Scanning Calorimetry ◽  
Bituminous Materials ◽  
Modified Binders ◽  
Bituminous Binders ◽  
Modified Binder

AbstractThe RILEM TC 272 PIM (Phase and Interphase behavior of innovative bituminous Materials)—TG1 Binder has initiated an inter-laboratory program investigating the phase and interphase behaviour of bituminous binders. Within the scope, four laboratories evaluated the low temperature properties of seven binders with differential scanning calorimetry (DSC). DSC has been accepted as a powerful tool to evaluate, among others, the glass transitions, Tg, monitoring the endothermic or exothermic heat flow of a material under controlled temperature conditions. There are different ways to run the test, conventional temperature linear-DSC (TL-DSC), and temperature modulation-DSC (TM-DSC). The latter has been proven as an efficient method differentiating the structural relaxation phenomena from the heat capacity. In this study, emphasis was placed on comparing the Tg measured by TL- and TM-DSC to improve the interpretation of binder glass transitions. In this study, the scope was restrained to two Polymer modified Binders (PmBs): a commercially available modified binder named PmB1 and a highly modified binder (7.5 wt% high vinyl SBS) named PmB2, were evaluated and compared with two neat bituminous binders. Based on the thermographs of the PmB2 obtained through this inter-laboratory program, it was observed that the modification by 7.5% SBS resulted in a decrease of the Tg. This reduction of Tg reflects the positive influence of SBS at low temperatures.

The Use of Bitumen Linear Viscoelastic Properties to Assess Rutting Sensitivity

2014 ◽  
Vol 567 ◽  
pp. 755-762
Author(s):  
Salah E. Zoorob ◽  
Ibrahim B. Kamaruddin ◽  
Napiah Madzlan
Keyword(s):  
Energy Equation ◽  
Empirical Relationship ◽  
Stored Energy ◽  
Theoretical Derivation ◽  
The Us ◽  
Modified Binders ◽  
Recent Developments ◽  
Linear Viscoelastic ◽  
Modified Binder ◽  
Performance Grading

The use of viscosity temperature relationships to predict creep performance of road bitumens have been shown to be inadequate in particular with respect to the analysis of polymer modified binders. In this paper we explore the origins of the US Strategic Highway Research Programmebinder performance grading system and detail two examples of more recent developments towards improved creep characterisation.Starting from first principles, an equation to analyse the ratio of dissipated to stored energy during sinusoidal loading of viscoelastic bitumen was derived. The energy equation was contrasted with an empirical relationship proposed by Anderson D.A., and with a second more theoretical derivation proposed by Shenoy A.Using frequency sweep data from a conventional 40/50 pen grade bitumen and a proprietary SBS modified binder, the applicability of the energy equation was subsequently compared to the two aforementioned post-SHRP creep relations. Recommendations are made regarding the suitability of the proposed relations in ranking bitumen creep performance.

scholarly journals The Influence Of The Rare Earth Metals Modification On The Fracture Toughness Of G17CrMo5-5 Cast Steel At Low Temperatures

2015 ◽  
Vol 60 (2) ◽  
pp. 773-777 ◽  
Author(s):  
I. Dzioba ◽  
J. Kasińska ◽  
R. Pała
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Rare Earth ◽  
Low Temperatures ◽  
Cast Steel ◽  
Rare Earth Metals ◽  
Positive Influence ◽  
Reference Temperature ◽  
Brittle To Ductile Transition ◽  
The Rare Earth

Abstract This paper presents the influence of the rare earth metals (REM) modification on mechanical properties and fracture toughness of G17CrMo5-5 cast steel at low temperatures. The REM was in the form of mishmetal. The research has been performed on serial (several) industrial melts. The fracture toughness values of unmodified and modified cast steel at the temperature range from −80°C to 20°C were tested. The reference temperatures of the brittle-to-ductile transition, TQ, for both unmodified and modified cast steel were determined. The positive influence of the modification by REM on the fracture toughness and the reference temperature TQ are shown.

The Crystal Structures at 10 K of the Trigonal Salts KMIII(NH3)6(ClO4)2Cl2, MIII = Os and Cr, and the Possibility of Phase Transitions

1999 ◽  
Vol 52 (3) ◽  
pp. 219 ◽  
Author(s):  
Philip A. Reynolds ◽  
Brian N. Figgis ◽  
Alexander N. Sobolev
Keyword(s):  
Differential Scanning Calorimetry ◽  
Transition Temperature ◽  
Crystal Structures ◽  
Low Temperatures ◽  
Simple Structure ◽  
Alkali Metal Cations ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Threefold Axis ◽  
X Ray

The crystal structures of KOs(NH3)3(ClO4)2Cl2 and KCr(NH3)6(ClO4)2Cl2 were determined at 10 K by X-ray diffraction, and for the osmium salt also at 293 K. At 293 K the osmium salt is trigonal, space group R 3m, with the same simple structure as others of this class of double salt. At 10 K, in agreement with previous radius ratio predictions, both crystals are best described as remaining R 3m. All previously studied members, with larger alkali metal cations, are twinned R 3 at low temperatures, with small, symmetry-breaking rotations of the hexaamminemetal(III) and perchlorate ions about the threefold axis. Differential scanning calorimetry on CsRu(NH3)6(ClO4)2Cl2 suggests that the R 3m to R 3 change is very extended in temperature with only a small discontinuity at the transition temperature.

THE INFLUENCE OF POLYMER ON RHEOLOGICAL AND THERMO OXIDATIVE AGING PROPERTIES OF MODIFIED BITUMEN BINDERS

2017 ◽  
Vol 79 (6) ◽  
Author(s):  
Nura Bala ◽  
Ibrahim Kamaruddin ◽  
Madzlan Napiah
Keyword(s):  
Softening Point ◽  
Storage Stability ◽  
Elastic Behavior ◽  
Modified Bitumen ◽  
Oxidative Aging ◽  
Modified Binders ◽  
Aging Resistance ◽  
Lower Temperature ◽  
Modified Binder ◽  
Temperature Susceptibility

Polymer modified bitumen (PMB) has been used for many years to improve the performance of asphalt concretes against premature pavement defects. In this research, modified samples were prepared with 2%, 3%, 4%, 5% and 6% Linear Low Density Polyethylene (LLDPE) polymer by weight of bitumen binder. The influence of LLDPE polymer was evaluated through binder properties test which includes penetration, softening point, storage stability, temperature susceptibility, rutting, fatigue and thermal oxidative aging resistance from a dynamic shear rheometer (DSR) measurements at a temperature of 20 OC to 60 OC. Results show that LLDPE polymer has a significant effect on binder properties. Penetration decreases and softening point increases with increasing LLDPE content on the modified binder after aging, which implies LLDPE improves the thermo oxidative aging resistance of the binder. Furthermore, the storage stability test shows that at higher LLDPE concentrations phase separation may occur. DSR analysis shows that modified binders have lower temperature susceptibility and higher aging resistance with increased stiffness and elastic behavior compared with unmodified binders. In addition, modified binders show enhanced resistance against high temperature rutting and at low temperature fatigue performance. It was found that the optimum LLDPE content is 6%.

scholarly journals EFFECT OF RH-WMA ADDITIVE ON ENGINEERING PROPERTIES OF BITUMEN PG-76/KESAN BAHAN TAMBAH RH-WMA KE ATAS SIFAT- SIFAT KEJURUTERAAN BITUMEN PG-76

2019 ◽  
Vol 81 (4) ◽  
Author(s):  
Gatot Rusbintardjo ◽  
Sitti Salmah Abdul Wahab ◽  
Faridah Hanim Khairuddin ◽  
Ahmad Nazrul Hakimi Ibrahim ◽  
Nur Izzi Md Yusoff ◽  
...  
Keyword(s):  
Contact Angle ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Warm Mix Asphalt ◽  
Molecular Structures ◽  
Engineering Properties ◽  
Morphological Properties ◽  
Modified Binders ◽  
Modified Binder

Pavement failure phenomena is normally caused by low quality of mixture materials, especially bitumen. The modification of bitumen is one of the alternatives to improve the performance of the material. Therefore, this study was conducted to investigate the performance of a polymer-modified binder (PG-76) with the addition of different percentages of Reduce Heat-Warm Mix Asphalt (RH-WMA) at 1, 2, 3, 4 and 5 % (by-weight of binder). Several testings such as penetration, softening point and ductility tests were conducted to determine the physical properties of PG-76 and RH-WMA modified binders. The molecular structures of the materials were analysed using Fourier transform infrared spectroscopy (FTIR) test while the contact angle test was conducted to investigate the type of binder’s surface. In addition, an optical microscopy test was carried out to determine the morphological properties of the modified binders. Results show that the PG-76’s hardness decreases with the increasing of RH-WMA percentage, but the ductility values are still within the specification. The FTIR test shows an increase of RH-WMA percentage does not provide a significant reaction of the binder and the original properties of the materials remain. The morphology test shows that all percentage of RH-WMA selected are well dispersed in bitumen PG-76. Based on the contact angle results, all the PG-76 and RH-WMA modified binders fall into hydrophobic category.

Archaeological Bone from Macro- to Nanoscale: Heat-Induced Modifications at Low Temperatures

2009 ◽  
Vol 8 ◽  
pp. 157-172 ◽  
Author(s):  
Céline Chadefaux ◽  
Ina Reiche
Keyword(s):  
Electron Microscopy ◽  
Low Temperatures ◽  
Type I Collagen ◽  
Bone Structure ◽  
Heating Temperature ◽  
Global Analysis ◽  
Type I ◽  
Scanning Calorimetry ◽  
Bone Material ◽  
X Ray

The present work focuses on the characterization of structural modifications in bone material induced by heating at low temperatures (90 - 250°C). This is of outmost importance when archaeological bone material is concerned. Changes occurring in the structure of the type I collagen and of the mineral-organic arrangement are especially investigated. This precise characterization required the combination of complementary analytical techniques: Differential Scanning Calorimetry (DSC) for global analysis of the collagen state of conservation, Scanning Electron Microscopy coupled with an Energy Dispersive X-Ray system (SEM-EDX), micro-Proton-Induced X-ray and Gamma-ray Emission (micro-PIXE/PIGE) for chemical analysis of the mineral fraction, Infrared microspectroscopy in attenuated total reflectance mode (micro-ATR-FT-IR) combined with curve-fitting for microscopic investigations and Transmission Electron Microscopy (TEM) on ultrathin sections to characterize the modifications in the mineral/organic interface at nanoscale. New criteria characterizing the effect of a thermal treatment at low temperatures on the bone structure from the macroscopic to the nanoscale were determined. There are namely a broadening of the Haversian canals, the inversion of the turns to -sheet ratio in the collagen structure determined by decomposition of the amide I IR band as well as a shift of amide II IR band position with the heating temperature to lower wavenumbers. At nanoscale, melting of the organic phase and clustering of hydroxyapatite (HAP) bone crystals can be observed. For comparison, unheated archaeological bones have been analyzed in order to test if the heat-induced modification can be distinguished from diagenetic alterations, generally dissolution-recrystallisation processes, in soils.

Effects of chemical composition and mean coordination number on glass transitions in Ge–Sb–Se glasses

2017 ◽  
Vol 31 (36) ◽  
pp. 1750342 ◽  
Author(s):  
Wen-Hou Wei
Keyword(s):  
Glass Transition ◽  
Chemical Composition ◽  
Coordination Number ◽  
Structural Phase ◽  
Stoichiometric Composition ◽  
Glass Transitions ◽  
Fragility Index ◽  
Scanning Calorimetry ◽  
Transition Formula ◽  
The Mean

Glass transitions in the Ge–Sb–Se glasses were investigated by means of differential scanning calorimetry (DSC) under non-isothermal conditions. The glass transition temperature [Formula: see text], activation energy of glass transition [Formula: see text], and fragility index as functions of the mean coordination number (MCN) and atomic percent of Ge were examined. The maximum value of [Formula: see text] in each group of the glasses occurred at the chemically stoichiometric composition, suggesting a glass transition threshold. The [Formula: see text] and fragility index were calculated from the heating rate dependence of [Formula: see text]. Both [Formula: see text] and fragility index show the minima at MCN = 2.4 which can be attributed to the structural phase transition of a covalently glassy network at MCN = 2.4. The analysis of the experimental results suggests that both the chemical composition and MCN have significant effects on the glass transitions in Ge–Sb–Se glasses.

Phase Separation In Blends of Polystyrene and Poly (P-METHYLSTYRENE) Using Thermal Analysis And Small-Angle Neutron Scattering

1993 ◽  
Vol 321 ◽  
Author(s):  
A. Xenopoulos ◽  
J. D. Londono ◽  
G. D. Wígnall ◽  
B. Wunderlich
Keyword(s):  
Thermal Analysis ◽  
Phase Separation ◽  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Small Difference ◽  
Glass Transitions ◽  
Scanning Calorimetry ◽  
Reliable Detection ◽  
Sans Data

ABSTRACTDifferential scanning calorimetry (DSC) was used to study blends of polystyrene (PS) and poly (p-Methylstyrene) (PpmS). The presence of two glass transitions on heating after quenching was interpreted as evidence of phase separation at the temperature of the liquid before quenching. The small difference between the glass transitions of the homopolymers in the PS/PpmS system of “13 K limits the reliable detection of double glass transitions for blends to concentrations between 30 and 70%. The results of the DSC technique are supported by comparison with small angle neutron scattering (SANS) data.

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