Changes In Rheological Properties Research Articles

Entanglements of Macromolecules and Their Influence on Rheological and Mechanical Properties of Polymers

Flexible macromolecules easily become entangled with neighboring macromolecules. The resulting network determines many polymer properties, including rheological and mechanical properties. Therefore, a number of experimental and modeling studies were performed to describe the relationship between the degree of entanglement of macromolecules and polymer properties. The introduction presents general information about the entanglements of macromolecule chains, collected on the basis of studies of equilibrium entangled polymers. It is also shown how the density of entanglements can be reduced. The second chapter presents experiments and models leading to the description of the movement of a single macromolecule. The next part of the text discusses how the rheological properties change after partial disentangling of the polymer. The results on the influence of the degree of chain entanglement on mechanical properties are presented.

Utilization of Nanocenospheres a waste material to improve the physical and rheological properties of SBS asphalt binders

The performance enhancement of asphalt binders by incorporating innovative additives has been a subject of significant research and industry interest. This study emphasizes the potential of Nano polymer composites as a promising additive for improving the performance of asphalt binders, providing valuable insights into developing advanced asphalt materials for sustainable road infrastructure construction and maintenance. It explores the utilization of nano cenospheres to amplify the attributes of Styrene-Butadiene-Styrene (SBS) modified asphalt binders. It introduces a novel approach by incorporating Nano polymer composites (NPC) comprising nanocenosphere particles and Styrene-butadiene-Styrene Particles. Nanocenosphere particles are the waste materials derived from coal combustion in thermal power plants. Styrene-butadiene-styrene is a type of thermoplastic elastomer, a synthetic rubber. A series of experimental tests, penetration, softening point, ductility, performance grading, temperature sweep, multiple stress and creep recovery, frequency sweep, linear amplitude sweep, and rutting aging index, is conducted to evaluate changes in physical and rheological properties. Results indicate that adding nano cenospheres particles in SBS asphalt binder enhances its softening point, elasticity recovery, rutting resistance, fatigue life, storage stability, and aging resistance compared to traditional SBS-modified asphalt binders. Statistical analyses were accomplished to comprehend the influence of the Nano polymer composites. This analysis provides valuable insights into the effects of nanocenospheres on SBS-modified binders. Through rigorous statistical analysis, a thorough interpretation of how the incorporation of nanocenospheres influences the attributes of Nano-polymer composites.

A Rheological Study on the Effect of Tethering Pro- and Anti-Inflammatory Cytokines into Hydrogels on Human Mesenchymal Stem Cell Migration, Degradation, and Morphology.

Polymer-peptide hydrogels are being designed as implantable materials that deliver human mesenchymal stem cells (hMSCs) to treat wounds. Most wounds can progress through the healing process without intervention. During the normal healing process, cytokines are released from the wound to create a concentration gradient, which causes directed cell migration from the native niche to the wound site. Our work takes inspiration from this process and uniformly tethers cytokines into the scaffold to measure changes in cell-mediated degradation and motility. This is the first step in designing cytokine concentration gradients into the material to direct cell migration. We measure changes in rheological properties, encapsulated cell-mediated pericellular degradation and migration in a hydrogel scaffold with covalently tethered cytokines, either tumor necrosis factor-α (TNF-α) or transforming growth factor-β (TGF-β). TNF-α is expressed in early stages of wound healing causing an inflammatory response. TGF-β is released in later stages of wound healing causing an anti-inflammatory response in the surrounding tissue. Both cytokines cause directed cell migration. We measure no statistically significant difference in modulus or the critical relaxation exponent when tethering either cytokine in the polymeric network without encapsulated hMSCs. This indicates that the scaffold structure and rheology is unchanged by the addition of tethered cytokines. Increases in hMSC motility, morphology and cell-mediated degradation are measured using a combination of multiple particle tracking microrheology (MPT) and live-cell imaging in hydrogels with tethered cytokines. We measure that tethering TNF-α into the hydrogel increases cellular remodeling on earlier days postencapsulation and tethering TGF-β into the scaffold increases cellular remodeling on later days. We measure tethering either TGF-β or TNF-α enhances cell stretching and, subsequently, migration. This work provides rheological characterization that can be used to design new materials that present chemical cues in the pericellular region to direct cell migration.

Application of black tea waste as eco-friendly deflocculant and rheology stabilizer for water-based mud

Maintaining and regulating the rheological properties of the drilling mud at the desired level is essential for successful drilling operations. Bentonite is the key additive used in most water-based drilling mud for enhanced rheological properties. However, the flocculation tendency of bentonite particles poses a significant challenge for the industry due to the undesirable and unpredictable changes in rheological properties of the fluid with downhole increasing temperature. This study aims to develop a low-cost and eco-friendly deflocculant from black tea waste (BTW) that can prevent the aggregation and flocculation of the bentonite and stabilize the rheology of bentonite-polymer muds. Rheological properties were evaluated with different concentrations (0.25%, 0.5%, 0.75%, and 1%) of BTW at 95 °F and 140 °F. The Bingham Plastic (BP) and Power Law (PL) models were studied to characterize the flow behavior and identify the best-fit model through statistical analysis. Along with rheological properties, thinning efficiency, mud stability, thermal aging effect, thixotropic behavior, and shear thinning behavior were investigated through different shear-temperature-time dependent tests. In addition, the lubricating properties and filtration loss characteristics were assessed at ambient conditions. Finally, the findings were compared with the industrially used deflocculant, lignosulphonate (LS). The results revealed that BTW can effectively prevent bentonite flocculation and stabilize the mud rheology even at a very low concentration of 0.25%. Significant improvements were observed in the lubricating and filtration characteristics. With the addition of 1% BTW, the filtrate loss, mud cake thickness, and friction coefficient were reduced by 22.2%, 50%, and 13.29%, respectively. The multifunctional activities of black tea waste (BTW) are attributed to its polyphenolic compounds, the presence of which was confirmed through UV–visible spectroscopy testing. The TG analysis confirmed that BTW remains thermally stable up to 200 °C. Considering the synergistic performance compared with lignosulphonate, availability, and environmental and economic acceptance, BTW may be effectively utilized as a multifunctional deflocculant and rheology stabilizer for water-based bentonite-polymer muds.

Dynamic changes in the aggregation-depolymerization behavior of Ovomucin-Complex and its binding to urease during in vitro simulated gastric digestion

Ovomucin-Complex extracted from egg white is expected to have a barrier function similar to gastric mucin. In this study, the dynamic changes in structure, rheological properties and binding ability of Ovomucin-Complex during in vitro simulated gastric digestion were investigated. The results from HPLC and CLSM showed that extremely acidic pH (pH = 2.0) promoted Ovomucin-Complex to form aggregation. Acid-induced aggregation may hinder its binding to pepsin, thus rendering Ovomucin-Complex resistant to pepsin. Consequently, most of the polymer structure and weak gel properties of Ovomucin-Complex retained after simulated gastric digestion as verified by HPLC, CLSM and rheological measurement, although there was a small breakdown of the glycosidic bond as confirmed by the increased content of reducing sugar. The significantly reduced hydrophobic interactions of Ovomucin-Complex were observed under extremely acidic conditions and simulated gastric digestion compared with the native. Noticeably, the undigested Ovomucin-Complex after simulated gastric digestion showed a higher affinity (KD = 5.0 ± 3.2 nm) for urease - the key surface antigen of Helicobacter pylori. The interaction mechanism between Ovomucin-Complex and urease during gastric digestion deserves further studies. This finding provides a new insight to develop an artificial physical mucus barrier to reduce Helicobacter pylori infection.

STUDY OF SOLUBILITY OF CO(NH2)2 - HOOC - COOH · NH2C2H4OH - H2O SYSTEM

In this work, the interaction of components in the CO(NH2)2 - HOOC - COOH ·NH2C2H4OH - H2O system was studied by visual polythermic method in the temperature range from -11.2 to 61°C. A polythermal solubility diagram of the system was constructed and the crystallization sites of ice, urea, monoethanolammonium oxalate, and the new phase ureamonoethanolammonium oxalate were determined.During the addition of monoethanolammonium oxalate to urea solutions of different concentrations, changes in rheological properties (pH, density, refractive index, viscosity) were recorded, and the results were found to be consistent with the polythermal solubility diagram. A new phase formed during the study of the CO(NH2)2 - HOOC-COOH · NH2C2H4OH - H2O system, ureamonoethanolammonium oxalate, was isolated and analyzed by confirmed using appropriate analytical methods (IR, Thermal, X-ray phase).

Effects of incubation time of plasma activated water (PAW) combined with annealing for the modification of functional properties of potato starch

The present study investigates the application of annealing and plasma-activated water (PAW) for starch modification, as alternative methods compared to the chemical one. Native potato starch was subjected to PAW, annealing with distilled water (DW-ANN), and the combination of the two (PAW-ANN) at different incubation times (1, 4, 8, and 12 h). The changes in rheological, pasting, and thermal properties were evaluated. The results showed that all treatments promoted significant modifications of the investigated parameters. In particular, while the pasting properties of the potato starch remained unchanged after the PAW treatment, G’ (elastic) and G’’ (viscous) of the PAW-treated starch were significantly (p < 0.05) higher than those of the native. DW-ANN significantly increased all rheological parameters and reduced peak viscosity, breakdown, and setback and significantly (p < 0.05) incremented pasting temperature, holding strength, and final viscosities of the potato starch may be due to cross-linking reaction. The combination of treatment (PAW-ANN) showed a synergistic effect leading to strong gel formation up to 4 h, while further treatment reduced the possibility of depolymerization. In conclusion, the combined treatment is a promising new green method to modify the properties of starch and improve its stability within a short treatment time.

Changes in rheology and components during the processing of Chinese traditional handmade hollow dried noodle

The study of the changes in rheological properties and components during the processing of Chinese traditional handmade hollow dried noodle (HHDN) is essential to explaining the excellent quality of HHDN. The dynamic oscillation frequency sweep, stress relaxation, and uniaxial extension characteristics of the dough after kneading, stretching, and resting were investigated at six sampling points during the processing of HHDN. The result showed that stretching led to an increase in G' and G0, and a significant decrease (P < 0.05) in extensibility from 131.02 mm to 57.99 mm. Confocal laser scanning microscopy (CLSM) was used to observe the microstructure of the gluten network, which was destroyed during stretching and restored during resting. Studies of changes in components showed that the stretching process resulted in a decrease in GMP content from 3.24 (g/100 g) to 3.18 (g/100 g), and the resting process resulted in β-sheets decreasing significantly (P < 0.05). The degree of starch pasting increased significantly (P < 0.05) after stretching. The results of the correlation analysis showed that components changes were highly correlated with the rheological properties during the processing of HHDN.

Thermadapt shape memory vitrimeric polymyrcene elastomer

Earlier studies of β-Myrcene (Myr)/ β-ketoester functional (acetoacetoxy)ethyl methacrylate (AAEMA) copolymers exhibited compositional drift, leading to ambiguity in microstructure/thermomechanical property correlations while shape memory recovery times were excessively long ~1 h. The terpene-based 1,3-diene Myr and AAEMA were copolymerized via nitroxide-mediated polymerization (NMP) with an initial Myr molar feed ratio ranging from 0.1 to 0.9. Reactivity ratios estimated by the Meyer-Lowry method were rMyr = 0.20 and rAAEMA = 0.22 with respective 95% confidence intervals of [0.13, 0.37] and [0.15, 0.23], suggesting alternating copolymerization. Bulk terpolymerization with styrene (Sty) afforded linear poly(Myr-stat-Sty-stat-AAEMA) prepolymers designed to modulate glass transition temperature Tg and stiffness. Subsequent cross-linking with isophorone diamine (IPDA) formed catalyst-free vinylogous urethane dynamic linkages. ATR-FTIR, dynamic mechanical analysis (DMA), and tensile measurements confirmed the recyclability of vitrimers through hot pressing at 110 °C, demonstrating minimal changes in rheological and mechanical properties even after four cycles. By heating the vitrimers to above their Tg (to ~45 °C), they exhibited a shape memory effect with high shape fixity and fast shape recovery (< 1 min). The vitrimers could undergo permanent shape reprogramming through reconfiguration of dynamic bonds at ~110 °C. This work shows the adaptability of Myr-based rubbers by vitrification and appropriate copolymerization for the synthesis of more sustainable elastomers with stimuli responsive properties.

Valorization of engineered biochar to develop ultra-high-performance fiber-reinforced concrete with low carbon emission

This research introduces an innovative approach to developing carbon-negative Ultra-High-Performance fiber-reinforced Concrete (UHPC) by incorporating substantial quantities of biochar, both as a binder and as an aggregate, replacing up to 25% by weight of Ordinary Portland Cement (OPC) and quartz sand (QS). The study examines the impact of biochar on cement hydration processes, microstructure evolution, and various other performance metrics in the modified UHPC. Samples were formulated with 3% double-hooked steel fibers and biochar quantities ranging from 5 to 25% by weight as substitutes for OPC and QS. The investigation included assessments of changes in rheological properties, strength metrics, long-term shrinkage, resistance to sulfate attacks, freeze-thaw durability, microstructure analysis, and a cost-benefit evaluation. Test results indicated that biochar-incorporated samples exhibited up to a 20% increase in heat evolution by the end of the seventh day and plastic energy at 28 days that rose to 32.14% as compared to control samples in 20% biochar-augmented versions. Shrinkage reduction varied between 58 and 69% at 210 days for samples with 20% biochar. Specifically, the mix containing 20% biochar (G2-M5-BC-20) significantly improved the 90-day compressive and flexural strength by 8.9 and 9.3%, and 30.6 and 36.8%, respectively, while further inclusion of biochar showed no marked enhancement in performance metrics. The G2-M5-BC-20 mix also demonstrated excellent resistance to sulfate attacks and freeze-thaw cycles, exhibiting the least mass loss and highest residual compressive strength. An initial cost-benefit revealed that biochar-enhanced UHPC could offer compelling financial benefits. Given its mechanical behavior, potential for harmful CO2 emissions, and economic viability, the G2-M5-BC-20 mix emerged as the most promising formulation, potentially generating an overall profit of $36 per cubic meter.

Rheological Properties and Segregation of Fresh UHPC with Fibers Affected by Initial Temperature of Concrete Mix

Within the framework of the project GAČR 21-24070S Model of fibre segregation in dependence on rheological properties of fresh HPC, the rheological properties and fibre segregation in fresh concrete mix depending on temperature changes have been verified. The rheological properties and fibre segregation have been verified under three temperature conditions (very low temperatures around 5 °C, normal temperature conditions around 20 °C and high temperatures above 30 °C). Comparison of the properties of UHPC with fibres at different temperature conditions has been performed on fresh mixtures mainly by spill tests. Subsequently, hardened test bodies, i.e. 40/40/160 beams, were verified in tensile bending and compression in all cases. The actual fibre segregation within the individual samples has also been verified by microscopic analysis. Different temperature conditions have been simulated by heating or cooling the input raw materials. The results have been compared by degree of changes in rheological properties and mechanical parameters.

The Effect of Heat- and Salt Treatment on the Stability and Rheological Properties of Chickpea Protein-Stabilized Emulsions

The aim of the study was to evaluate the effect of heat- (95 °C) and/or salt (0.1 M NaCl) treatment on the physical stability and rheological properties of oil-in-water emulsions stabilized with chickpea protein concentrates (CPCs) for various purposes. Thus, the particle size distribution (PSD), shear behavior, and long-term Turbiscan stability of the prepared emulsions were examined. The oscillatory (dynamic) measurements were also performed to obtain information on the viscoelasticity of tested fluids during thermal treatment. The obtained results indicated that the emulsion stabilized with gelling CPC (eCg) was Newtonian fluid with a homogeneous structure, but susceptible to creaming. Heat-treated eCg exhibited a sol–gel transition at 86 °C and formed fine-stranded aggregates without affecting stability. In turn, heat-induced gelation of eCg in the presence of 0.1 M NaCl resulted in the formation of an aggregated, spatial gel network, stabilization of the system, and a significant change in both shear rheological properties and PSD. Contrariwise, emulsions stabilized with standard CPC (eCs) were unstable heterogeneous systems containing both fine particles &lt; 1 μm and coarse particles of about 100 μm, exhibiting shear-thinning and yield stress. The heat-induced viscoelasticity of eCs was reversible, while heat- and salt-treated emulsions did not form a gel.

Sprouted Oats (Avena sativa L.) in Baked Goods: From the Rheological Properties of Dough to the Physical Properties of Biscuits

AbstractThis study investigated the impact of sprouted oats (SO) on dough properties and biscuit features. Unsprouted oats (USO) and SO (for 48 h and 72 h) were studied in wheat dough at 10, 20, and 30%, and gluten aggregation, mixing, and extensional properties were evaluated. USO caused a weakening in gluten aggregation capacity, an increase in water uptake, development time and dough rigidity, and a decrease in extensibility. Dough enriched in SO showed mixing profiles similar to wheat, but using SO strongly affected dough extensional properties, indicating gluten weakening. Changes in rheological properties suggested the use of SO at 20% level in biscuit production. Using oats did not affect either biscuit size or volume, but decreased both the hardness and the toughness of the product, with 72 h-SO having the greatest impact, especially on hardness. Further study will address consumer acceptability and nutritional features of the developed baked product.

Exploring the influence of sweet potato powder on the physicochemical characteristics, oxidative potential and sensory perception of mayonnaise

SummaryReduced fat mayonnaise was prepared by substituting oil with sweet potato powder at concentrations of 2%, 4% and 6%. The changes in physicochemical, oxidative, rheological, microbial and organoleptic properties of functional reduced fat mayonnaise were investigated. The results revealed that sweet potato powder significantly improved the antioxidant activity (2.63–31.6%), rheological attributes, nutritional content and shelf life stability of mayonnaise during the storage time of 21 days. Rheological evaluation illustrated the stabilisation of samples with the addition of sweet potato powder, with a significant reduction in oil droplet size (6.78–2.16 μm) and an increase in firmness (0.941–1.84 N) and adhesiveness (41.21–76.78 × 10−3 Nm). Emulsion stability (93.3–99.2%) was significantly (P &lt; 0.05) enhanced by supplementation with sweet potato powder. The presence of carotenoids in sweet potato improved colour and increased the L* (73.4%) and b* (31.4%) values. Preliminary sensory evaluation demonstrated that taste, texture, mouthfeel and overall acceptability were perceived better in the samples supplemented with sweet potato powder. Our findings suggest that sweet potato powder can be a nutrient enhancer and a considerable alternative to synthetic antioxidants and stabilisers for oil‐in‐water food emulsions.

Polysaccharide from Clitocybe squamulosa: Gel-forming properties and its compound effect with food thickener

To study the gel-forming properties of polysaccharide from the fruiting body of Clitocybe squamulosa (CSFP) and its degradation product (UH-CSFP), the changes in steady-state and dynamic rheological properties of CSFP and UH-CSFP under different conditions (polysaccharide mass fraction, temperature, pH, and salt ion concentration) were studied. Polysaccharides with good gel-forming properties were selected and mixed with common edible thickeners (gelatin, guar gum, and locust bean gum), after which the properties of the composite gel were assessed. The steady-state rheological results showed that CSFP and UH-CSFP were pseudoplastic fluids, their apparent viscosity decreased with increasing temperature, the viscosity was greatest when the pH was 7. The addition of Na+ and Ca2+ could increase the viscosity, and the viscosity of UH-CSFP was lower than that of CSFP at the same mass fraction. The results of dynamic rheology indicated that G´ and G´´ of CSFP and UH-CSFP increased with increasing mass fraction, pH, and ion concentration (0.01 M to 1 M), and G´´ was always smaller than G´ indicating weak gel behavior. The thixotropy-related experimental results showed that the thixotropy ring area of CSFP and UH-CSFP increased with increasing mass fraction, the ring area of CSFP was larger than that of UH-CSFP, and the gel strength of CSFP was greater than that of UH-CSFP. The results of CSFP and three types of edible gels showed that the composite gels were pseudoplastic fluids, and their apparent viscosity was ranked (in descending order) as follows: guar bean gum, locust bean gum, and gelatin. The addition of CSFP improved the gel-forming properties of guar gum but did not significantly improve the gel properties of locust bean gum and gelatin. This study provides a theoretical basis for the selection of processing methods and the application of polysaccharides.

Cryoprotective effect of curdlan on frozen wheat gluten: With respect to physicochemical properties and molecular structure

Curdlan alleviates the quality deterioration of frozen dough during storage by a mechanism related to retarded migration of moisture. However, the strengthening effect of curdlan on the gluten structure needs to be proved. Therefore, the effect of curdlan on physicochemical properties and molecular structure changes of frozen wheat gluten was investigated. Frozen storage resulted in decreased water-holding capacity and viscoelasticity properties, as well as increase in oil-holding capacity and surface hydrophobicity. However, curdlan significantly inhibited the rheological and physicochemical properties changes of gluten. Scanning electron microscope results showed that the structure of gluten with curdlan had relatively smoother and less damaged surface during frozen storage. Curdlan alleviated the depolymerization of gluten macropolymers (GMP) by restraining the breakage of S–S bonds, with GMP depolymerization degree of 20% after 90 days of storage, significantly lower than that of the control (38%). Curdlan restrained the transition of α-helix to β-turn and antiparallel β-sheet, and suppressed the protein unfolding and chromophores exposure. Curdlan interacted with gluten prominently by hydrogen bonds, followed by hydrophobic interactions, thus strengthening the gluten structure. Alleviation of dough quality loss during frozen storage by curdlan could be related to its strengthening gluten structure.

Structural, Thermo‐Functional, and Rheological Properties of Dielectric Modified Underutilized Jicama (Pachyrhizus, spp.) Starch

AbstractIn this study, underutilized jicama starch (JS) is treated in dielectric‐heating at different power (300, 450, 600 W) and time (1, 3, 5 min), and the change in structural, thermo‐functional, and rheological properties is observed. The dielectric modification increases the water absorption (0.81–2.88 g g−1), whereas the oil absorption capacity (1.02–0.83 g g−1) and bulk density (0.52–0.39 g mL−1) are reduced as compared to native starch. Lightness (95.46–96.26) of JS non‐significantly varies with dielectric‐heating, whereas a significant effect is observed in redness (0.01–0.06) and yellowness (3.74–4.24). The apparent viscosity of all treated samples shows shear thinning behavior. All the pasting properties other than the setback and pasting temperature of dielectric treated samples are significantly (p &lt; 0.05) decreased at higher power than control. The onset (46.50–81.67 °C), peak (64–99.23 °C), and end temperature (68.27–100.77 °C) of gelatinization transition increased, which shows better thermal stability as compared to control. The strong‐peak for the control and treated sample is observed at around 1000 cm−1 wavenumber in the Fourier transform infrared spectroscopy. The structural changes have been observed by X‐ray diffraction analysis (XRD) and scanning electron micrographs (SEM) shows shrinkage and deformation at each power and time.

Study of the Effect of Continuous Thermal Effects on the Shear Stability of Magnetorheological Grease

Magnetorheological dampers in the service of the medium in a project experience continuous thermal effects, frequent reciprocating shear and other complex conditions. Shear stability is an important indicator of the reliability of a magnetorheological media service. Magnetorheological grease (MRG) was prepared using hydroxy iron powder with a mass fraction of 30% and lithium grease of different consistency grades as a continuous phase. The results of magnetic and rheological properties analysis were combined to investigate the mechanism of the continuous thermal effect on the shear stability of MRG. The results show that changes in the temperature field and magnetic field cause significant changes in the magnetic and rheological properties of MRG. At low temperatures and low magnetic fields, the soap fiber structure unique to MRG can effectively inhibit the movement of magnetic particles, with slight changes in the rheological properties and excellent shear stability. When the temperature increases to 80 °C, 00#MRG is damaged by the high temperature. The soap fiber structure is fractured and reorganized, and the rheological properties change significantly. However, the rheological properties of 1#MRG remain largely unchanged during the magnetic field enhancement to saturation, showing better shear stability. The higher consistency continuous phase has excellent heat resistance and better shear performance stability in the face of thermomagnetic coupling conditions, but the fiber breakage caused by continuous reciprocating shear poses a challenge to the service stability of MRG.

Modifying rheological properties of psyllium by gamma irradiation enables development of low glycaemic index food with a predicted gastrointestinal tolerance

Gel forming dietary fibre like psyllium (PS) is effective in slowing down rate of digestion as well as absorption of glucose thereby reducing the postprandial glucose level and hence is used to develop functional foods for diabetic patients. The fortification level is however limited which otherwise elicit unwanted rheological response and poor sensorial quality in final product. In the present study this limitation was overcome by improving the functionality of the fibre by gamma radiation processing of the polysaccharides. We assessed the changes in rheological properties of radiation processed PS (RPPS) at different doses which enabled us to optimise the irradiation dose and levels of fortification of the RPPS in wheat flour for preparation of Indian unleavened bread (chapati). We observed that PS processed at a dose of 25 kGy could be incorporated to a level as high as 14 % in wheat flour yielding a sensorially better product compared to unfortified wheat flour. Further, the most striking effect observed for RPPS fortified chapati was reduction in the release of glucose upon subjecting to simulated gastrointestinal digestion. Finally, clinical and in vitro fermentation studies also confirmed a low GI value and high gastrointestinal tolerance of RPPS fortified chapati.

Performance and Mechanism of Using Low-Cost Fumed Silica Nanoparticles in Enhancing High Viscosity Modified Asphalt

Fumed silica nanoparticles (FSNPs) have shown significant potential in polymer modification due to their economic viability. This study aims to explore the impact of FSNPs on the performance of high viscosity modified asphalt (HVMA). For a comprehensive view, we also introduced Nano-SiO2 and Nano-TiO2, common nano-modifiers, for comparison with the results achieved by FSNPs. The morphology of these nano-modifiers was observed with Field Emission Scanning Electron Microscopy (FESEM). The changes in rheological, chemical, and thermal properties of HVMA before and after modification were evaluated using techniques such as Dynamic Shear Rheometer (DSR), Fluorescence Microscope, Fourier Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis-Differential Scanning Calorimetry (TGA-DSC). The FESEM results revealed that FSNPs form a branchlike network while Nano-SiO2 and Nano-TiO2 lack specific structures or clear interconnections. Further rheological testing reveals that, when compared to Nano-SiO2 and Nano-TiO2, FSNPs improve the high-temperature performance of HVMA by 2–3 times and bolster its fatigue resistance by 1.2–3 times, while reducing temperature sensitivity. These enhancements are attributed to the synergistic strengthening between the FSNP's branchlike network and the SBS polymer network structure, underlining the significance of FSNPs' shape and connectivity in HVMA rheological property improvement.