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A styrene-butadiene-styrene (SBS) latex modifier can be used for asphalt modification due to the fact of its energy-saving, construction convenience, and economic advantages. The objective of this study was to investigate the influence of asphalt type and SBS latex dosage on the rheological properties, compatibility, and storage stability of asphalt through temperature and frequency sweep, steady-state flow, multiple stress creep and recovery (MSCR) tests, Cole-Cole plots and thermal storage tests. The results indicated that high SBS latex content is beneficial for improving anti-rutting, anti-fatigue, viscous flow resistance, and elastic recovery abilities of modified asphalt. The chemical composition of asphalt had a significant effect on the properties of the SBS latex-modified asphalt. High asphaltenes and low resins were favorable to enhancing anti-rutting and recovery properties but weakened the anti-fatigue, compatibility, and storage stability of modified asphalt. Furthermore, compared to SBS particle-modified asphalt, SBS latex-modified asphalt had greater rutting and fatigue resistance. However, SBS latex-modified asphalt had some disadvantages in compatibility and storage stability. Comprehensively considering the balance of viscoelastic properties, compatibility, and storage stability of SBS latex-modified asphalt, the mixing dosage of SBS latex modifier is recommended at 4.0 wt% which could feasibly replace SBS particle in asphalt modification.

This paper studies performance comparison of two shuttle-based storage and retrieval system (SBS/RS) configurations developed on flexible or non-flexible travel policies of shuttles in the system. In the non-flexible SBS/RS, a shuttle is dedicated to a tier so that it cannot travel out of its dedicated aisle and tier. A lifting mechanism is installed in each aisle to provide vertical travel for loads. In flexible SBS/RS, shuttles can travel between tiers by a separate lifting mechanism installed on the other edge point of each aisle. The advantage of that flexible design is that there might be decreased number of shuttles settling in the system compared to the non-flexible design. We simulate the two system configurations and conduct an experimental design for the comparison purpose. Based on the three-performance metrics: total investment cost, throughput rate and energy consumption per transaction, the results show that mainly the flexible system provides better results which might be considered as future system investment for SBS/RS.

This paper uses a fluorescence microscope to study the microstructure of dry modified asphalt, and compares and analyzes the micro and macro performance of dry and wet modified asphalt. The results show that: in terms of micro performance, when the modifier content is 6%, the dry modifier (SBS-T) becomes to a compact network structure in the asphalt when the shear time is 5 minutes, and it takes 45 min for the modifier to achieve the same result to the wet method. And the macro performance indicators of penetration, softening point, ductility, and viscosity show that the modification effect of asphalt is better by dry modifier is 5 minutes after shearing than the modification effect of asphalt by wet modifier is 45 minutes.

Polyvinylidene fluoride (PVDF)-based piezoelectric materials (PEMs) have found extensive applications in energy harvesting which are being extended consistently to diverse fields requiring strenuous service conditions. Hence, there is a pressing need to mass produce PVDF-based PEMs with the highest possible energy harvesting ability under a given set of conditions. To achieve high yield and efficiency, solution blow spinning (SBS) technique is attracting a lot of interest due to its operational simplicity and high throughput. SBS is arguably still in its infancy when the objective is to mass produce high efficiency PVDF-based PEMs. Therefore, a deeper understanding of the critical parameters regarding design and processing of SBS is essential. The key objective of this review is to critically analyze the key aspects of SBS to produce high efficiency PVDF-based PEMs. As piezoelectric properties of neat PVDF are not intrinsically much significant, various additives are commonly incorporated to enhance its piezoelectricity. Therefore, PVDF-based copolymers and nanocomposites are also included in this review. We discuss both theoretical and experimental results regarding SBS process parameters such as solvents, dissolution methods, feed rate, viscosity, air pressure and velocity, and nozzle design. Morphological features and mechanical properties of PVDF-based nanofibers were also discussed and important applications have been presented. For completeness, key findings from electrospinning were also included. At the end, some insights are given to better direct the efforts in the field of PVDF-based PEMs using SBS technique.

Due to the superiorities of Styrene butadiene styrene (SBS) modified asphalt, it is widely used in civil engineering application. Meanwhile, accurately predicting and obtaining performance parameters of SBS modified asphalt in unison is difficult. At present, it is essential to discover an accurate and simple method between the input and output data. ANNs are used to model the performance and behavior of materials in place of conventional physical tests because of their adaptability and learning. The objective of this study discussed the application of ANNs in determining performance of SBS modified asphalt, based on attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) tests. A total of 150 asphalt mixtures were prepared from three matrix asphalt, two SBS modifiers and five modifier dosages. With the most suitable algorithm and number of neurons, an ANN model with seven hidden neurons was used to predict SBS content, needle penetration and softening point by using infrared spectral data of different modified asphalts as input. The results indicated that ANN-based models are valid for predicting the performance of SBS modified asphalt. The coefficient of determination (R2) of SBS content, softening point and penetration prediction models with the same grade of asphalt exceeded 99%, 98% and 96%, respectively. It can be concluded that ANNs can provide well-satisfied regression models between the SBS content and infrared spectrum statistics sets, and the precision of penetration and softening point model founded by the same grade of asphalt is high enough to can meet the forecast demand.

As the most important thermoplastic and thermosetting modifiers, styrene–butadiene–styrene triblock copolymer (SBS) and epoxy resin have been widely applied in asphalt modifications. In this paper, epoxy SBS-modified asphalts (ESBAs) were prepared with epoxy monomer, curing agent and SBS-modified asphalts (SBAs) with various styrene–butadiene structures, which in turn were subjected to laser scanning confocal microscopy (LSCM), viscous measurements, thermal analysis and tensile tests. The LSCM results revealed that both polymer-rich phase and fluorescent particle-rich phase were observed in the asphalt matrix. Moreover, the number of SBS particles in SBAs increased with the increase of styrene contents. The presence of SBS decreased the size of dispersed domains in the continuous epoxy phase of the neat epoxy asphalt binder (EAB). For ESBAs, a double phase separation occurred between SBA and epoxy in the continuous epoxy phase and between asphalt and SBS in the dispersed SBA phase. Both number and size of SBS domains in the dispersed SBA phase of ESBAs increased with the increase of styrene contents. The inclusion of styrenic polymers increased the viscosity of the neat EAB. The viscosity of ESBAs increased with the increase of average molecular weights of the styrenic polymers. The addition of styrenic polymers increased the glass transition temperature (Tg) and storage modulus (E′) of the neat EAB. Meanwhile, the inclusion of styrenic polymers weakened the damping properties of the neat EAB. The styrene-butadiene structures had little effect on the Tg and damping properties of ESBAs. The E′ of ESBAs decreased with the increase of styrene contents. The presence of SBS enhanced the thermal stability of the neat EAB. Tensile results showed that the addition of SBS increased the tensile strength of the neat EAB.

The thermal behavior of bitumen BND 70/100 and polymer modified bitumens (PMBs) based on it was studied by methods of simultaneous thermal analysis (STA) and microcalorimetry. The effect of SBS (Styrene–Butadiene–Styrene) polymer and plasticized by vacuum gas oil SBS (P-SBS) polymer on the structural organization of PMBs and their thermal stability was revealed. In the base bitumen, the presence of a crystallizing fraction (CF) was detected. It was found that CF is preserved when P-SBS is introduced into bitumen, but is not preserved when SBS is introduced. It is assumed that the absence of CF when introducing only SBS is associated with an increase in the solvent capacity of the bituminous phase in relation to paraffinic hydrocarbons due to selective adsorption of aromatic hydrocarbons by the SBS. The plasticized SBS has less effect on the solvent capacity of the bituminous phase. It was shown that thermal destruction onset temperature of the base bitumen is much higher than the temperature of preparation of the PMBs, and that the addition of SBS and P-SBS to the base bitumen reduces its resistance to thermal degradation. It was established that the destruction energy of PMBs is significantly higher than that of base bitumen and depends on the composition of the additives introduced. The data obtained indicate the influence of the quality of the used polymer on the internal structure of the bituminous phase, which in turn, has a great influence on the performance characteristics of PMBs.

Styrene Butadiene Styrene (SBS) polymer-modified asphalt binders have become widely used in asphalt pavement because of their advantages in high- and low-temperature performance and fatigue resistance. Asphalt pavement is inevitably exposed to sunlight and ultraviolet (UV) radiation during its construction and service life. However, consideration of the aging effect of UV radiation is still limited in current pavement design and evaluation systems. In order to evaluate the impact of UV radiation on the aging properties of SBS-modified asphalt binders, UV aging tests were performed on Rolling Thin Film Oven Test (RTFOT)-aged samples with different UV radiation intensities and aging times. Sixteen different groups of tests were conducted to compare the rheological properties and functional group characteristics of SBS-modified asphalt binders. Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), FTIR, and SEM tests were conducted to evaluate the aging mechanisms in various UV aging conditions. The results found that UV radiation seriously destroys the network structure formed by the cross-linking effect in SBS-modified asphalt binders, which aggravates the degradation of SBS and results in a great change of rheological properties after UV aging. The nature of SBS-modified asphalt binder aging resulted from the degradation of SBS and the changes of asphalt binder base composition, which lead to the transformation of colloidal structure and the deterioration of asphalt binder performance. The tests also found that continuous UV radiation can increase shrinkage stress in the asphalt binder surface and leads to surface cracking of the asphalt binder.

According to UAE Health Ministry and Dubai Healthcare City reports, 15% of Dubai residents have a chronic respiratory disease such as asthma. Moreover, 90% of the 150,000 patients at Al Ain Hospital suffered from upper respiratory tract respiratory diseases, bronchitis, or asthma. Sick Building Syndrome (SBS) has emerged as a social problem in the United Arab Emirates (UAE). The Dubai Municipality regulates Indoor Air Quality (IAQ) with strict stipulations before moving in, but they are relatively passive about regulations related to healthy living. This paper aims to explore the actual state of perception of the IAQ from townhouse residents in Dubai, UAE. The characteristics of the resident’s perceptions of the IAQ are identified, and the influential factors affecting residents’ perceptions of IAQ are extracted. As a methodology, the survey was conducted on four townhouse projects in Dubai from December 2021 to January 2022. A total of 114 copies were distributed, and 98 documents were used. Analysis of the survey data was processed using IBM SPSS Statistics 26.0. The results showed a statistically significant correlation between the cognitive and anxiety levels of SBS with the presence or absence of experience. It was statistically confirmed that the most influential factors were the age of the children and the occupancy time of housewives and children. This is because of the perception that wives who spend a relatively long time in the house and their young children are exposed to indoor air pollution for a long period of time and are easily affected by this influence on the concerns about young children about SBS. Ninety-five percent of the respondents answered that they knew more than average about SBS, indicating a very high level of awareness. As for the degree of anxiety, 87.0% of the respondents felt higher levels of anxiety than usual. However, most of them did not know or were indifferent to the understanding of the air quality improvement methods. The awareness of actual contents was lower than that of residents who assessed that they knew about SBS.

To investigate the effect of styrene-butadiene-styrene (SBS) modifier content on the viscoelastic behavior of SBS-modified asphalt (SBSMA) at different temperatures and phase structures, the star SBS modifier was chosen to fabricate seven types of SBSMA with different contents. Multiple stress creep recovery (MSCR), linear amplitude sweep (LAS), and low-temperature frequency sweep tests were adopted to study the influence of SBS modifier content on the viscoelastic performance of SBSMA at high to low temperatures. The SBSMA’s microstructure with different contents was investigated using a fluorescence microscope. The results indicated that the change in non-recoverable creep compliance and creep recovery rate was bounded by 4.5% content at high temperatures, with an apparent turning point. The changing slope of content at less than 4.5% was much higher than that of the content greater than 4.5%. At medium temperatures, the fatigue life of SBSMA increased exponentially with the rising modifier content. The rate of increase in fatigue life was the largest as the content increased from 4.5% to 6.0%. At low temperatures, the low-temperature viscoelastic property index G (60 s) of SBSMA decreased logarithmically as the modifier content increased. In terms of the microscopic phase structure, the SBS modifier gradually changed from the dispersed to the continuous phase state with the increasing SBS modifier content.