Effect of Heat Aging on Properties and Structure of SBS Modified Bitumen Waterproof Membrane

2021 ◽  
Vol 1035 ◽  
pp. 951-957
Author(s):  
Yan Heng He ◽  
Zhi Long Cao ◽  
Yang Yang Ge ◽  
Zhao Yang Liu ◽  
Jiang Ting Li ◽  
...  
Keyword(s):  
Low Temperature ◽  
Aging Time ◽  
Carbonyl Compounds ◽  
Softening Point ◽  
Degradation Rate ◽  
Modified Bitumen ◽  
Maximum Tension ◽  
Initial Stage ◽  
Before And After ◽  
Low Temperature Flexibility

The properties of SBS modified bitumen waterproof membrane (SMBM) will deteriorate under the action of heat. In this paper, SBS modified bitumen (SMB) and SMBM were aged at 80 °C for different times (0,10,20,30,40 days). The low temperature flexibility, softening point, viscosity and mass changes ratio of SMB and mechanical properties of SMBM before and after aging were tested, the microstructure and chemical structure of SMB were investigated by fluorescence microscope (FM) and Fourier transform infrared spectroscopy (FTIR). The results show that the low temperature flexibility, softening point and viscosity of SMB decrease significantly at the initial stage of heat aging (10 days), especially the influence of heat aging on the low temperature flexibility and viscosity of SMB is more obvious, and their properties degradation rate slowdown in the later stage of aging. The mass changes ratio of SMB first decreases and then increases with aging time. FM shows that the network crosslinking structure of SMB is destroyed gradually with the extension of aging time. The network crosslinking structure disappears after 40 days of heat aging. FTIR shows that carbonyl and sulfoxide compounds are increasing after aging, more carbonyl compounds than sulfoxide compounds are formed after aging for 10 days, and the degradation rate of SBS decreases. The maximum tension of SMBM first increases and then decreases, the elongation at maximum tension decreases with aging time.

Effect of FCC Slurry on Performance of SBS Modified Bitumen

2020 ◽  
Vol 993 ◽  
pp. 1361-1366
Author(s):  
Tian Wei Zhang ◽  
Jian Xin Li ◽  
San Peng Mao ◽  
Gui Tao Zheng ◽  
Jian Ying Yu
Keyword(s):  
Low Temperature ◽  
Physical Properties ◽  
Catalytic Cracking ◽  
Softening Point ◽  
Petrochemical Industry ◽  
Fluorescence Microscope ◽  
Fluid Catalytic Cracking ◽  
Modified Bitumen ◽  
Low Temperature Flexibility

Fluid catalytic cracking (FCC) slurry is a by-product of petrochemical industry rich in aromatics. In this paper, the effect of FCC slurry on the physical properties of SBS modified bitumen was investigated by softening point, penetration, ductility and low temperature flexibility test. The influence of FCC slurry on the compatibility of SBS modified bitumen was evaluated by fluorescence microscope and segregation test. The results show that FCC slurry improves the softening point, penetration, ductility and low temperature flexibility of SBS modified bitumen. Fluorescence microscope showed that FCC slurry promotes the dispersion of SBS in bitumen, which is conducive to the formation of network crosslinking structure of SBS modified bitumen. The segregation test indicated that the compatibility of SBS with bitumen was improved with the content of FCC slurry increasing.

Effect of Chemical Corrosion on Properties of SBS Modified Bitumen for Waterproofing Membranes

2021 ◽  
Vol 1035 ◽  
pp. 958-965
Author(s):  
Jiang Ting Li ◽  
Xiao Bin Han ◽  
San Peng Mao ◽  
Gui Tao Zheng ◽  
Jian Ying Yu
Keyword(s):  
Low Temperature ◽  
Alkaline Solution ◽  
Softening Point ◽  
Structural Changes ◽  
Acidic Solution ◽  
Underground Engineering ◽  
Modified Bitumen ◽  
Chemical Corrosion ◽  
Low Temperature Flexibility ◽  
Saline Solutions

SBS modified bitumen membrane used in underground engineering and coastal buildings would be corroded by chemical media, which greatly influenced the service life of waterproofing membranes. In this paper, SBS modified bitumen (MB), SBS modified bitumen with stone powder (MBS) and SBS modified bitumen with talc powder (MBT) were corroded by acidic, alkaline, and saline solutions for different time to evaluated the effect of chemical corrosion on the properties of SBS modified bitumen waterproofing membrane. The mass change ratio, low temperature flexibility, softening point and viscosity of SBS modified bitumen were investigated, and Fourier infrared spectroscopy (FTIR) was used to analyze the chemical structural changes of SBS modified bitumen after corrosion. The results showed that the mass of SBS modified bitumen decreased, the low temperature performance decreased, and the softening point increased after corrosion by chemical solutions. The influence of acidic and saline solution was more serious on SBS modified bitumen with fillers, and the properties of MBS has greatest degradation in acidic solution compared with MB and MBT. In alkaline solution, the properties degradation of MBT and MBS was less than that of MB, which indicated that filler could inhibit the alkaline corrosion of SBS modified bitumen. FTIR showed that C=C decreased more in acidic solution, while C=O and S=O of SBS modified bitumen increased significantly after alkaline solution corrosion, which indicated that acidic solution corrosion easily caused SBS degradation, while alkaline solution corrosion was easy to oxidize SBS and bitumen.

Preparation and Properties of SBS Modified Deoiled Asphalt and Slurry Blends

2019 ◽  
Vol 944 ◽  
pp. 1252-1258
Author(s):  
Yi Gu ◽  
Yu Shi Li ◽  
Xiao Qiao Huang ◽  
Jian Ying Yu
Keyword(s):  
Low Temperature ◽  
Softening Point ◽  
Chemical Structure ◽  
Petroleum Refining ◽  
Gas Oil ◽  
Uv Aging ◽  
Before And After ◽  
Low Temperature Flexibility ◽  
Structure And Microstructure ◽  
By Products

Deoiled asphalt (DOA) and slurry are by-products of petroleum refining process. In this paper, blending asphalt (DST) based on DOA, slurry and vacuum gas oil and SBS modified DST (SMDST) were prepared. The aging resistance of SMDST was investigated by thermal aging (TA) and ultraviolet (UV) aging. Meanwhile, the chemical structure and microstructure of SMDST before and after aging were characterized by Fourier transform infrared spectroscopy (FTIR) and fluorescence microscopy. The results showed that the softening point, ductility at 5 °C and low temperature flexibility of SMDST increased gradually with the increase of SBS content. When SBS content was 12 wt%, the softening point, ductility at 5 °C and low temperature flexibility of SMDST were 105 °C, 55 cm and -25 °C, respectively. After TA and UV, the low temperature flexible reductions of SMDST with 12 wt% SBS were 3 °C and 2 °C, respectively, which demonstrated that aged SMDST still had good crack resistance in low temperature. FTIR analysis indicated that the carbonyl (C=O) and the sulfoxide (S=O) characteristic peaks of SMDST were enhanced after aging to a certain extent. However, the fluorescence microscope observation showed the network structure of SMDSB was not damaged significantly, which implies that SMDST has a favourable anti-aging performance.

Effect of Non-Sulfur Stabilizer on Performance of SBS Modified Bitumen

2021 ◽  
Vol 1035 ◽  
pp. 944-950
Author(s):  
Zhao Yang Liu ◽  
San Peng Mao ◽  
Gui Tao Zheng ◽  
Zhi Long Cao ◽  
Lian Li ◽  
...  
Keyword(s):  
Low Temperature ◽  
Aging Process ◽  
Storage Stability ◽  
Growth Index ◽  
Thermal Storage ◽  
Cross Linking ◽  
Modified Bitumen ◽  
Temperature Performance ◽  
Aging Resistance ◽  
Low Temperature Flexibility

Based on the reason that SBS modified bitumen (SMB) with sulfur stabilizer is easy to degrade during aging, a novel non-sulfur stabilizer, P-benzoquinone oxime (GMF), was used to modify SMB. The effects of GMF and sulfur stabilizer on the thermal storage stability, low-temperature performance and aging resistance of SMB were investigated. The results indicate that GMF is more beneficial to improve the thermal storage stability, the low temperature flexibility and softening point of SMB than that of sulfur. And GMF can restrain the degradation of the low temperature flexibility of SMB after thermal aging as compared with sulfur. Fourier transform infrared spectroscopy indicates that the aging growth index of GMF/SBS modified bitumen is 33.5% lower than that of sulfur/SBS modified bitumen after aging. Fluorescence microscope proves that the addition of GMF can prevent the destruction of cross-linking network structure of SBS in bitumen during aging process, which also demonstrates that GMF can improve the aging resistance of SMB. Therefore, GMF can be more suitable as a stabilizer for SMB.

scholarly journals Plasma Exosomal miRNA Levels after Radiotherapy Are Associated with Early Progression and Metastasis of Cervical Cancer: A Pilot Study

2021 ◽  
Vol 10 (10) ◽  
pp. 2110
Author(s):  
Oyeon Cho ◽  
Do-Wan Kim ◽  
Jae-Youn Cheong
Keyword(s):  
Cervical Cancer ◽  
Pilot Study ◽  
Biological Functions ◽  
Patients With Cancer ◽  
Initial Stage ◽  
Exosomal Mirnas ◽  
Early Progression ◽  
Before And After ◽  
Microenvironmental Factors ◽  
Exosomal Mirna

Plasma exosomal miRNAs are key regulators of cell-cell interactions associated with several biological functions in patients with cancer. This pilot study aimed to investigate the log2 fold change (log2FC) of the expression of exosomal miRNAs and related mRNAs in the blood of patients with cervical cancer to identify prognostic markers better than those currently available. We sequenced plasma exosomal RNA from 56 blood samples collected from 28 patients with cervical cancer, who had been treated with concurrent chemoradiotherapy (CCRT). Changes in the expression of miRNAs and mRNAs before and after CCRT were represented as log2FC. Their biological functions were studied by miRNA-mRNA network analysis, using ingenuity pathway analysis, after the selection of two groups of miRNAs, each associated with early progression (EP) and metastasis, also described as initial stage. Seven patients experienced EP, three of whom died within four months after progression. Reduced levels of miR-1228-5p, miR-33a-5p, miR-3200-3p, and miR-6815-5p and increased levels of miR-146a-3p in patients with EP revealed unresolved inflammation, with accompanying increased expression of PCK1 and decreased expression of FCGR1A. Increased levels of miR-605-5p, miR-6791-5p, miR-6780a-5p, and miR-6826-5p and decreased levels of miR-16-1-3p (or 15a-3p) were associated with the degree of metastasis and led to the systemic activation of myeloid, endothelial, and epithelial cells, as well as neurons, phagocytes, and platelets. Log2FCs in the expression of miRNAs and mRNAs from plasma exosomes after CCRT are associated with EP and metastasis, reflecting unresolved inflammation and systemic microenvironmental factors, respectively. However, this study, supported by preliminary data insufficient to reach clear conclusions, should be verified in larger prospective cohorts.

scholarly journals Effects of equal channel angular pressing and heat treatments on the microstructures and mechanical properties of selective laser melted and cast AlSi10Mg alloys

2021 ◽  
Vol 21 (3) ◽  
Author(s):  
Przemysław Snopiński ◽  
Mariusz Król ◽  
Marek Pagáč ◽  
Jana Petrů ◽  
Jiří Hajnyš ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Equal Channel Angular Pressing ◽  
Heat Treatments ◽  
Electron Backscattered Diffraction ◽  
Angular Pressing ◽  
Low Temperature Annealing ◽  
Transmission Electron ◽  
Before And After ◽  
The Impact

AbstractThis study investigated the impact of the equal channel angular pressing (ECAP) combined with heat treatments on the microstructure and mechanical properties of AlSi10Mg alloys fabricated via selective laser melting (SLM) and gravity casting. Special attention was directed towards determining the effect of post-fabrication heat treatments on the microstructural evolution of AlSi10Mg alloy fabricated using two different routes. Three initial alloy conditions were considered prior to ECAP deformation: (1) as-cast in solution treated (T4) condition, (2) SLM in T4 condition, (3) SLM subjected to low-temperature annealing. Light microscopy, transmission electron microscopy, X-ray diffraction line broadening analysis, and electron backscattered diffraction analysis were used to characterize the microstructures before and after ECAP. The results indicated that SLM followed by low-temperature annealing led to superior mechanical properties, relative to the two other conditions. Microscopic analyses revealed that the partial-cellular structure contributed to strong work hardening. This behavior enhanced the material’s strength because of the enhanced accumulation of geometrically necessary dislocations during ECAP deformation.

Low-Temperature Syntheses of Thioketals from Enol Ethers and Carbonyl Compounds.

ChemInform ◽  
2003 ◽  
Vol 34 (19) ◽  
Author(s):  
Arnaud Martel ◽  
Sopa Chewchanwuttiwong ◽  
Gilles Dujardin ◽  
Eric Brown
Keyword(s):  
Low Temperature ◽  
Carbonyl Compounds ◽  
Enol Ethers

Zirconia‐dispersed polyethylene glycol composites with a low temperature‐degradation rate

2020 ◽  
pp. 50384
Author(s):  
Allif Rosyidy Hilmi ◽  
Nibras Fuadi Muwwaqor ◽  
Nur Aini Fauziyah ◽  
Suminar Pratapa
Keyword(s):  
Polyethylene Glycol ◽  
Low Temperature ◽  
Degradation Rate

The modification of bitumen with styrene–butadiene–styrene, ethylene vinyl acetate and varying the amount of reactive ethylene terpolymer

2017 ◽  
Vol 50 (3) ◽  
pp. 241-255 ◽  
Author(s):  
Seyfullah Keyf
Keyword(s):  
Vinyl Acetate ◽  
Softening Point ◽  
Elastic Recovery ◽  
Ethylene Vinyl Acetate ◽  
Modified Bitumen ◽  
Penetration Index ◽  
Different Types ◽  
Styrene Butadiene Styrene ◽  
Styrene Butadiene ◽  
Butadiene Styrene

In this article, 50/70 penetration grade TUPRAS bitumen was modified. Reactive elastomeric terpolymer (Elvaloy RET; DuPont Company), ethylene vinyl acetate (EVA) and styrene–butadiene–styrene (SBS) polymers were used in bitumen modification. Set hours of the tests were applied to samples taken from the obtained modified bitumen mixture. Varying amount of reactive ethylene terpolymer with weight ratios of 0.5%, 1.0%, 1.5%, 2.0% and 2.5% were introduced to the mixture of raw bitumen with 1.0% SBS and 1.0% EVA. Penetration, penetration index, softening point, ductility and elastic recovery tests were performed with these modified bitumen and raw bitumen. The samples of raw bitumen and modified bitumens of 2.0% Elvaloy RET, 1.0% SBS and 1.0% EVA were investigated by means of IR spectroscopy. The raw bitumen was modified with SBS, EVA and RET, and it was determined that penetration and ductility values were decreased while penetration index, softening point and elastic recovery were increased. The purpose of this study is to research the improving properties of 50/70 penetration grade–modified bitumen used in highways of Turkey. The most important characteristics (such as softening point, penetration and % elastic recovery) of new polymer-modified bitumen (NPMB) containing 2.5% EVA, 1% RET and 1% SBS were compared with eight different types of polymer-modified bitumens in Turkey (TPMB). NPMB provided all required parameters (softening point, penetration and % elastic recovery) for five different types of TPMBs (TPMB 70-16, TPMB 70-22, TPMB 76-16, TPMB 76-22 and TPMB 82-16).

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