scholarly journals Investigation of rheological properties of asphalt emulsions

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Enhao Zhang ◽  
Xiaofei Qi ◽  
Liyan Shan ◽  
Dongsheng Li
Keyword(s):  
Rheological Properties ◽  
Shear Viscosity ◽  
Loss Modulus ◽  
Critical Issue ◽  
Solid Content ◽  
Zero Shear Viscosity ◽  
Asphalt Emulsions ◽  
Palierne Model ◽  
Better Than

AbstractRheology is critical issue in the workability, stabilization and engineering performance of asphalt emulsions. The objective of this study is to investigate the rheological properties of asphalt emulsions. To achieve this goal, a preshear protocol was introduced and four kinds of asphalt emulsions were tested base on preshear. Firstly, the necessarity of preshear was analyzed and the suitable range of preshear rate and preshear time of the studied asphalt emulsions were given. Then, the rheological properties of asphalt emulsions were studied after preshear. Finally, the palierne model was modified and the storage/loss modulus of asphalt emulsions was accurately predicted by the modified palierne model. The results showed that it’s necessary to preshear asphalt emulsions before testing rheological properties. The viscosity, zero shear viscosity, storage and loss modulus of asphalt emulsions increase with the increase in solid content. The prediction results of the modified palierne model are better than that of palierne model. The storage/loss modulus of asphalt emulsions can be effectively predicted by the modified palierne model. This study has considerable meaning to the promotion of production and manufacturing of asphalt emulsions.

Thermal Property, Morphology, Mechanical and Rheological Properties of a Modified Bio-Polymers Prepared by Blending Poly(3-Hydrobutyrate-Co-4-Hydrobutyrate) with Chain Extenders

2010 ◽  
Vol 152-153 ◽  
pp. 924-930
Author(s):  
Mei Li ◽  
Zhi Qiang Li ◽  
Jun Xu ◽  
Dun Sheng Wei ◽  
Hong Wei Zhu ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Shear Viscosity ◽  
Loss Modulus ◽  
Freeze Fracture ◽  
Fracture Morphology ◽  
Steady Shear ◽  
Thermal Transitions ◽  
Remarkable Effect ◽  
Steady Shear Viscosity ◽  
Chain Extenders

Modified Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] was prepared by melt reactive blending P(3HB-co-4HB) with chain extenders (ADR-4367). Thermal transitions, spherulitic and freeze-fracture morphology, mechanical and rheological properties of the chain extended bio-materials were investigated. The results show that glass transition temperatures and crystallization temperatures increase, crystallinity and diameters of spherulites decrease, there are amorphous parts dispersed among the crystalline phase, and the bio-materials transfer from brittleness to toughness and ductility. Steady shear viscosity of the modified P(3HB-co-4HB) increases by about one order of magnitude, melts of the modified P(3HB-co-4HB) behave more viscoelasticity by storage modulus and loss modulus correlated with oscillatory shear frequency. Addition of ADR-4367 with contents of 4~6 wt% in the blends is enough to branching and coupling the co-polymer chains and brings remarkable effect on improving mechanical properties, steady shear viscosity and viscoelasticity.

Effect of Solvent Cleaning on Thermo-Mechanical and Rheological Properties of Plastic Wastes from Municipal Solid Waste (MSW)

2020 ◽  
Vol 856 ◽  
pp. 230-236
Author(s):  
Laongdaw Techawinyutham ◽  
Wiroj Techawinyutham
Keyword(s):  
Municipal Solid Waste ◽  
Solid Waste ◽  
Rheological Properties ◽  
Loss Modulus ◽  
Tensile Modulus ◽  
Cleaning Process ◽  
Maximum Value ◽  
Plastic Wastes ◽  
Thermal Stability Of ◽  
Better Than

The plastics from municipal solid waste (MSW) were modified to improve cleanness for adding value. The stir and sonication were performed as cleaning processes. Xylene, tetrachloroethylene, chloroform, acetone and toluene were used as solvent cleaning. The most suitable cleaning process was sonication method with cleaning time of 5 min and the appropriate solvent was xylene for washing the plastic wastes for further study in terms of thermo-mechanical and rheological properties. The cleaning process was successful as evidence in thermogravimetric analysis (TGA) results. The properties of new plastics, cleaned plastic wastes and plastic wastes were compared and analyzed. Tensile strength of the specimens from plastic wastes was slightly decreased; however, elongation and impact strength of cleaned plastic wastes and plastic wastes sharply dropped as compared to new plastics. Tensile modulus of cleaned plastic wastes was slightly better than that of new plastics. Thermal stability of plastic waste was slightly lower than that of new plastic. Shear storage modulus (Gʹ), shear loss modulus (Gʺ) and shear viscosity (η) of new plastics showed the maximum value; on the other hand, those properties of cleaned plastic wastes and plastic wastes were similar. The cleaning method with solvent did not destroy thermo-mechanical and rheological properties of the cleaned plastic wastes.

scholarly journals Effect of Citrus Fiber on the Rheological Properties of Dough and Quality of the Gluten-Free Bread

2020 ◽  
Vol 10 (19) ◽  
pp. 6633
Author(s):  
Jarosław Korus ◽  
Lesław Juszczak ◽  
Mariusz Witczak ◽  
Rafał Ziobro
Keyword(s):  
Rheological Properties ◽  
Loss Modulus ◽  
Average Pore Size ◽  
Quality Parameters ◽  
Partial Replacement ◽  
Gluten Free ◽  
Zero Shear Viscosity ◽  
Average Pore ◽  
Swelling Properties ◽  
Water Binding

The aim of the study was to evaluate the use of citrus fiber for the nutritional enrichment and technological improvement of gluten-free bread. A partial replacement of starch in bread formulation was analyzed in terms of the dough’s rheological properties and selected quality parameters of the bread. The results allowed to conclude that the presence of citrus fiber modifies the rheological properties of the dough, causing an increase in storage modulus (G′) and loss modulus (G″) values, as well as zero shear viscosity, accompanied with a decrease in instantaneous compliance (J0) and viscoelastic compliance (J1) to the applied stress, which reflects dough strengthening caused by significantly greater water binding and swelling properties characteristic of this ingredient. The introduction of the citrus fiber to bread formulations caused a significant decrease in bread volume and structure changes in crumb visible in the larger porosity and average pore size. The presence of citrus fiber affected texture, decreasing crumb hardness, springiness, cohesiveness and chewiness in comparison to the control. It could also be observed that the use of citrus fiber results in limited crumb hardening during storage, which indicates that this component could be an effective factor retarding the staling of the gluten-free bread based on starch and hydrocolloids.

scholarly journals Rheology by Design: A Regulatory Tutorial for Analytical Method Validation

Pharmaceutics ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 820 ◽  
Author(s):  
Ana Simões ◽  
Margarida Miranda ◽  
Catarina Cardoso ◽  
Francisco Veiga ◽  
Carla Vitorino
Keyword(s):  
Yield Point ◽  
Shear Viscosity ◽  
Loss Modulus ◽  
Shear Thinning ◽  
Critical Parameters ◽  
Relative Area ◽  
Zero Shear Viscosity ◽  
Analytical Method Validation ◽  
Lower Shear ◽  
The Impact

The increasing demand for product and process understanding as an active pursuit in the quality guideline Q8 and, more recently, on the draft guideline on quality and equivalence of topical products, has unveiled the tremendous potential of rheology methods as a tool for microstructure characterization of topical semisolid dosage forms. Accordingly, procedure standardization is a dire need. This work aimed at developing and validating a methodology tutorial for rheology analysis. A 1% hydrocortisone cream was used as model cream formulation. Through a risk assessment analysis, the impact of selected critical method variables (geometry, temperature and application mode) was estimated in a broad range of rheological critical analytical attributes—zero-shear viscosity, upper-shear thinning viscosity, lower-shear thinning viscosity, infinite-shear viscosity, rotational yield point, thixotropic relative area, linear viscoelastic region, oscillatory yield point, storage modulus, loss modulus, and loss tangent. The proposed validation of the approach included the rheometer qualification, followed by the validation of numerous operational critical parameters regarding a rheology profile acquisition. The thixotropic relative area, oscillatory yield point, flow point and viscosity related endpoints proved to be highly sensitive and discriminatory parameters. This rationale provided a standard framework for the development of a reliable and robust rheology profile acquisition.

Prediction of Zero-Shear Viscosity of Linear Polybutadienes from the Crossover Point Using Doi-Edwards Theory

1988 ◽  
Vol 61 (5) ◽  
pp. 812-827 ◽  
Author(s):  
Ramesh R. Rahalkar ◽  
Henry Tang
Keyword(s):  
Shear Viscosity ◽  
Amorphous Polymers ◽  
Simple Expression ◽  
Crossover Frequency ◽  
Crossover Point ◽  
Zero Shear Viscosity ◽  
Plateau Modulus ◽  
Good Agreement

Abstract Based upon the Doi-Edwards theory, a simple expression has been obtained for zero-shear viscosity in terms of the plateau modulus and the crossover frequency. There are no adjustable parameters in the expression. The model is in very good agreement with the zero-shear viscosity values for linear polybutadienes, the typical discrepancy being ∼5–10%. If the model can be validated for other linear amorphous polymers, it may become possible to estimate the zero-shear viscosity by measuring a single Theological parameter (the crossover frequency).

Electrical conductivity and rheological properties of carbon black based conductive polymer composites prior to and after annealing

2021 ◽  
pp. 096739112110012
Author(s):  
Qingsen Gao ◽  
Jingguang Liu ◽  
Xianhu Liu
Keyword(s):  
Electrical Conductivity ◽  
Carbon Black ◽  
Percolation Threshold ◽  
Rheological Properties ◽  
Network Formation ◽  
Loss Modulus ◽  
Conductive Polymer ◽  
Complex Viscosity ◽  
Electrical Percolation ◽  
Electrical Percolation Threshold

The effect of annealing on the electrical and rheological properties of polymer (poly (methyl methacrylate) (PMMA) and polystyrene (PS)) composites filled with carbon black (CB) was investigated. For a composite with CB content near the electrical percolation threshold, the formation of conductive pathways during annealing has a significant impact on electrical conductivity, complex viscosity, storage modulus and loss modulus. For the annealed samples, a reduction in the electrical and rheological percolation threshold was observed. Moreover, a simple model is proposed to explain these behaviors. This finding emphasizes the differences in network formation with respect to electrical or rheological properties as both properties belong to different physical origins.

scholarly journals Impact of Graphene Oxide on Zero Shear Viscosity, Fatigue Life and Low-Temperature Properties of Asphalt Binder

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3073
Author(s):  
Abbas Mukhtar Adnan ◽  
Chaofeng Lü ◽  
Xue Luo ◽  
Jinchang Wang
Keyword(s):  
Graphene Oxide ◽  
Fatigue Life ◽  
Low Temperature ◽  
Shear Viscosity ◽  
Storage Stability ◽  
Asphalt Binder ◽  
Asphalt Binders ◽  
Test Results ◽  
Zero Shear Viscosity ◽  
Modified Asphalt

This study has investigated the impact of graphene oxide (GO) in enhancing the performance properties of an asphalt binder. The control asphalt binder (60/70 PEN) was blended with GO in contents of 0%, 0.5%, 1%, 1.5%, 2%, and 2.5%. The permanent deformation behavior of the modified asphalt binders was evaluated based on the zero shear viscosity (ZSV) parameter through a steady shear test approach. Superpave fatigue test and the linear amplitude sweep (LAS) method were used to evaluate the fatigue behavior of the binders. A bending beam rheometer (BBR) test was conducted to evaluate the low-temperature cracking behavior. Furthermore, the storage stability of the binders was investigated using a separation test. The results of the ZSV test showed that GO considerably enhanced the steady shear viscosity and ZSV value, showing a significant contribution of the GO to the deformation resistance; moreover, GO modification changed the asphalt binder’s behavior from Newtonian to shear-thinning flow. A notable improvement in fatigue life was observed with the addition of GO to the binder based on the LAS test results and Superpave fatigue parameter. The BBR test results revealed that compared to the control asphalt, the GO-modified binders showed lower creep stiffness (S) and higher creep rate (m-value), indicating increased cracking resistance at low temperatures. Finally, the GO-modified asphalt binders exhibited good storage stability under high temperatures.

Sign in / Sign up

Export Citation Format

Share Document