Newtonian Fluid Behavior Research Articles

Structural and Rheological Properties of Nonedible Vegetable Oil-Based Resin.

Jatropha oil-based polyol (JOL) was prepared from crude Jatropha oil via an epoxidation and hydroxylation reaction. During the isocyanation step, two different types of diisocyanates; 2,4-toluene diisocyanate (2,4-TDI) and isophorone diisocyanate (IPDI), were introduced to produce Jatropha oil-based polyurethane acrylates (JPUA). The products were named JPUA-TDI and JPUA-IPDI, respectively. The success of the stepwise reactions of the resins was confirmed using 1H nuclear magnetic resonance (NMR) spectroscopy to support the Fourier-transform infrared (FTIR) spectroscopy analysis that was reported in the previous study. For JPUA-TDI, the presence of a signal at 7.94 ppm evidenced the possible side reactions between urethane linkages with secondary amine that resulted in an aryl-urea group (Ar-NH-COO-). Meanwhile, the peak of 2.89 ppm was assigned to the α-position of methylene to the carbamate (-CH2NHCOO) group in the JPUA-IPDI. From the rheological study, JO and JPUA-IPDI in pure form were classified as Newtonian fluids, while JPUA-TDI showed non-Newtonian behaviour with pseudoplastic or shear thinning behaviour at room temperature. At elevated temperatures, the JO, JPUA-IPDI mixture and JPUA-TDI mixture exhibited reductions in viscosity and shear stress as the shear rate increased. The JO and JPUA-IPDI mixture maintained Newtonian fluid behaviour at all temperature ranges. Meanwhile, the JPUA-TDI mixture showed shear thickening at 25 °C and shear thinning at 40 °C, 60 °C and 80 °C. The master curve graph based on the shear rate for the JO, JPUA-TDI mixture and JPUA-IPDI mixture at 25 °C, 40 °C, 60 °C and 80 °C was developed as a fluid behaviour reference for future storage and processing conditions during the encapsulation process. The encapsulation process can be conducted to fabricate a self-healing coating based on a microcapsule triggered either by air or ultra-violet (UV) radiation.

Thermo-fluidic significance of non Newtonian fluid with hybrid nanostructures

The main purpose of this investigation is to analyze the flow and heat transfer behavior of a non Newtonian fluid (Oldroyd B fluid) with hybrid nanostructure subject to externally inclined magnetic field. Cattaneo Christov heat flux model is incorporated in the energy equation. Non linear thermal radiation and viscous dissipation mechanisms are considered. Shooting technique is implemented to accomplish the numerical solution. The outcomes of the numerical computations are discussed with the aid of relevant graphs. The performed study reveals that rise in magnetic field strength shows opposite behavior to fluid velocity and temperature. Thermal relaxation time factor controls the rate of heat transportation. Rise in curvature parameter accelerates the fluid flow while that of angle of inclination of magnetic field imparts the reverse effect.

Magnetite/Poly(ortho-anisidine) Composite Particles and Their Electrorheological Response.

Magnetic and semiconducting Fe3O4/poly(o-anisidine) (POA) core/shell composite particles were fabricated by an oxidation process using Fe3O4 synthesized separately. The dispersion stability in a liquid medium and the electrical conductivity of synthesized particles were improved because of the conductive POA polymeric shell. The morphological, microstructural, compositional/elemental, and thermal behaviors of the particles were characterized using SEM with energy dispersive X-ray spectroscopy, TEM, XRD, and thermogravimetric analysis, respectively. A smart electro-magneto-rheological suspension containing Fe3O4/POA particles with two functionalities, magnetism and conductivity, was prepared. Its electrorheological properties were investigated at different electric field strengths using a rotational rheometer. Without an electric field, the sample demonstrated typical Newtonian fluid behavior, as expected. However, while under the electric field, it exhibited a solid-like behavior, and the dynamic (or elastic) yield stress of the ER fluid increased linearly as a function of the electric field strength in a power-law function with an index of 2.0, following the polarization mechanism.

In situ impregnation of continuous thermoplastic composite prepreg for additive manufacturing and automated fiber placement

Components made from thermoplastic composites (TPC) by additive manufacturing (AM) and automated fiber placement (AFP) are gaining popularity because of the material system’s inherent advantages over thermosets, but high material costs and limited production flexibility are hindering more widespread use. This paper discusses prototyping, fluid flow modeling, and testing of a novel in situ preimpregnator (prepregger) for lower-cost TPC feedstock used in AM and AFP. Prior attempts by researchers to address this technical need have generally resulted in low-quality prepreg with low fiber volume fraction (Vf) and high void content, which can be explained by Darcy’s law applied to the highly viscous polymer melts. Uniformly spreading the fiber tow thin before impregnation is the key to rapid and complete impregnation. Based on initial experiments with a flexible experimental setup to quickly test concepts, a prototype prepregger consisting of dry fiber payout reel with slight torsional resistance, fixed pin fiber spreader, double slot die coater fed with polymer melt from a microextruder, consolidator with pultrusion exit die, and prepreg downstream drive mechanism was designed and built. Predictions from a steady-state flow model of the coating die/microextruder system assuming creeping flow and Newtonian fluid behavior agreed well with experimental flow measurements for a variety of polymer melts and operating conditions. Once ideal input parameters were determined, prepreg tape specimens exhibited complete impregnation but low Vf and excessive encapsulation due to insufficient consolidation and removal of excess resin. Experiments where pultrusion dies were used for filament manufacturing showed significantly improved Vf and prepreg quality. Future work is suggested to facilitate commercialization of this promising process technology.

Conditional and unconditional second-order structure functions in bubbly channel flows of power-law fluids

The influence of non-Newtonian fluid behavior and the Eötvös number on conditional and unconditional second-order structure functions of bubbly channel flows has been investigated by conducting a series of direct numerical simulations at a friction Reynolds number of 127.3. Two Eötvös numbers have been considered (Eo = 0.3125 and Eo = 3.75) together with three different power-law indexes representing shear-thinning (n = 0.7), Newtonian (n = 1.0), and shear-thickening (n = 1.3) fluid behavior. The scaling of the second-order structure functions (SFs) can be translated into an inertial range scaling of the turbulent kinetic energy spectrum. However, because of the discontinuous character of the fluid properties in bubbly flows, SFs are more easily accessible than turbulence spectra, which are based on Fourier transform. It has been found that the different parameters (i.e., Eo, n) have an influence on the energy content as well as the peak location of the compensated second-order SFs (i.e., the dimensions of the large scales). However, after appropriate scaling, the curves nearly collapse. To confirm and further explain the above findings, directional length scales have been evaluated and discussed in detail. Finally, the anisotropy of the Reynolds stress tensor and dissipation tensor has been analyzed in terms of the Lumley triangle, showing that bubbly channel flows are less isotropic than their single-phase counterpart, although they are more homogeneous in the channel center. While the dissipation tensor is slightly more isotropic than the Reynolds stress tensor in the bulk region of the channel flow, overall, a very similar behavior is observed.

Controlling the flow and heat transfer characteristics of power-law fluids in T-junctions using a rotating cylinder

In this work, the combined influence of the power-law rheology and isothermal rotating cylinder has been investigated numerically on the flow and heat transfer characteristics in a T-channel. The cylinder placed at the T-junction imitates the functioning of a rotating valve which controls the flow rate and the enthalpy distribution of the exiting streams in two branches. The range of parameters considered in this work is as: Reynolds number, 1 < Re ≤ 50, power-law index, 0.2 ≤ n ≤ 1, Prandtl number, 10 ≤ Pr ≤ 100 and non-dimensional circumferential velocity of the cylinder, −5 ≤ α ≤ 5. Results suggest that the rotating cylinder can be used as a technique to create and/or reduce the formation of momentum and thermal boundary layers in the flow domain. The rotational velocity (α) and power-law flow index (n) are seen to have a strong effect on the critical Reynolds number for both the main and side branches. The hydrodynamic forces acting over the cylinder surface exerted by the fluid in the flow and perpendicular to the flow direction show a strong relationship with the cylinder rotation. For a particular combination of the studied parameters, these forces are also seen to be negative. Further, it is interesting to note that as the power-law index increases, the flow split ratio decreases while it shows an opposite trend with the Reynolds number. It can also be varied by switching the rotation direction. The dimensionless exiting temperature and enthalpy distribution are seen to have a strong relationship with the direction of rotation, fluid power-law index, Reynolds and Prandtl numbers. The mean values of the Nusselt number are seen to increase and/or decrease with the rotational velocity. For the anticlockwise rotation, the maximum suppression in the heat transfer is seen to be 79% while 62% for the clockwise rotation for the Newtonian fluid behaviour at low Prandtl number and high Reynolds numbers.

Formulation of highly stable PCM nano-emulsions with reduced supercooling for thermal energy storage using surfactant mixtures

This study was to develop stable phase change material (PCM)-water nano-emulsions with low supercooling and low viscosity using two-surfactant mixtures by the phase inversion temperature (PIT) method. The PCM agent n-hexadecane was mixed with Brij L4 as the primary surfactant and polyethylene-block-poly(ethylene glycol) (PE-b-PEG), Tween 60 or Tween 80 as a co-surfactant to form stable nano-emulsions. The results showed that the droplet size, viscosity and PIT point as well as the stability of PCM nano-emulsions were strongly dependent on the combination, mass ratio and total concentration of the two surfactants. In 25% (w/w) PCM nano-emulsions, an optimum formulation was the surfactant combination of Brij L4 and Tween 60 at 6:4 mass ratio, mixed with PCM at 11:20 mass ratio. The corresponding nano-emulsion had a high stability, a small droplet size of 60 nm and desirable Newtonian fluid behaviour with a relatively low viscosity of 50 mPa s. The addition of n-octacosane as a nucleating agent was effective to reduce the emulsion supercooling, though the supercooling degree was notably increased after multiple thermal cycles. The optimized 25% PCM nano-emulsion with 2% (w/w) n-octadecane showed an excellent stability over 120 days and 300 thermal cycles with a droplet size below 80 nm, a supercooling degree of ~5 °C and a latent heat of ~50 J/g, which was very promising for further development and application as a cooling storage medium.

CFD modeling of particle settling in drilling fluids: Impact of fluid rheology and particle characteristics

The settling of drilling cuttings is important for the drilling and clean-out operations. The current article provides a Computational Fluid Dynamics (CFD) modeling study of particle settling behavior during the drilling operations, with a special focus on the impact of fluid rheology, flow regime, particle size and shape on the settling rate. The Eulerian-Lagrangian method are adopted to track particle trajectories in a shear-thinning fluid under quiescent conditions. The rheological properties of the drilling fluids are described by different rheological models. Settling of spherical and ellipsoidal cuttings, with various aspect ratios, is studied for particles with a diameter ranging between 2 and 6 mm. The settling behavior is predicted for particles with narrow (0.5–2 mm), medium (0.5–6 mm) and broad (0.5–10 mm) particle size distributions (PSD). Applying a non-Newtonian power-law model at low shear rates, where the fluid is in the Newtonian regime, resulted in 11–19% over-prediction of settling velocities as compared to the experimental data. On the other hand, ignoring the particle-induced shear rate by assuming a Newtonian fluid behavior in the transition regime showed 8–10% difference between the estimated and experimental settling rates. Therefore, the CFD computations of settling rates suggest that Cross and Carreau models provide more accurate predictions than a simple power-law model. The selection of the suitable rheological model is a key factor in predicting settling in drilling fluids. This is more important for small particles where the Newtonian behavior is dominant and particle-induced shear rate is low. Ellipsoidal cuttings exhibited significantly greater resistance to settling as compared to spherical particles, mainly due to the increased drag force. Further, the terminal settling velocity of ellipsoidal cuttings consistently increased with the particle aspect ratio. Cuttings with broad PSD showed ~32 times higher settling velocity than particles with narrow PSD. CFD results are validated with experimental measurements. Moreover, results for settling of non-spherical particles are validated with an empirical correlation. Agreement of experimental and theoretical predictions is observed when the fluid and flow regimes are well identified and described.

Rheological characterization of polymeric solutions used in spray drying process

The present works contributes with a rheological characterization of the most commonly used polymers and solvents to formulate amorphous solid dispersions by means of spray drying process: copovidone, hydroxypropyl methylcellulose (HPMC), hydroxypropyl methylcellulose acetate succinate (HPMCAS) and a copolymer of methacrylic acid and methyl methacrylate (1:1 ratio and commercially known as Eudragit L100). The organic-based solutions are characterized in terms of surface tension, shear viscosity and relaxation time. HPMC and HPMCAS solutions exhibit shear thinning behaviour, i.e. decrease of shear viscosity with the increasing shear rate imposed, while the samples with Eudragit L100 can be considered Boger fluids, showing a constant viscosity but maintaining its viscoelastic character. Under uniaxial extensional flow, these polymers solutions exhibit a viscoelastic behavior with an increasing relaxation time with an increasing concentration, and in some cases showed a ‘beads-on-string’ effect. In contrast, copovidone showed a Newtonian fluid behavior, with the absence of elasticity. The fundamental understanding and characterization of the present work may be further applied to atomization modelling and support and expedite spray drying process development.

Squeeze Flow of a Newtonian Fluid under Different Test Speeds

In this paper, the squeeze flow behavior of Newtonian fluid was investigated with a series of squeeze tack laboratory experiments. The Newtonian fluid was squeezed out radially between two parallel and circular plates. From the flow curves obtained in the squeeze tack experiments, rheological parameters such as yield stress in tension and in squeeze, have been investigated. The results indicate that the values of yield stress in squeeze and in tack of the testing material are relatively small. These values gradually decrease with increasing sample thickness. This shows that the squeezing and tacking process does not affect the testing material, glucose in this case. Although the experimental results are not much, a linear relationship can be found between tensile and squeeze stress of Newton fluid in the experiment. This is especially evident at low test speeds

Molecular interpretation of the non-Newtonian viscoelastic behavior of liquid water at high frequencies

Using classical as well as ab-initio molecular dynamics simulations, we calculate the frequency-dependent shear viscosity of pure water and water-glycerol mixtures. In agreement with recent experiments, we find deviations from Newtonian-fluid behavior in the THz regime. Based on an extension of the Maxwell model, we introduce a viscoelastic model to describe the observed viscosity spectrum of pure water. We find four relaxation modes in the spectrum which we attribute to i) hydrogen-bond network topology changes, ii) hydrogen-bond stretch vibrations of water pairs, iii) collective vibrations of water molecule triplets, and iv) librational excitations of individual water molecules. Our model quantitatively describes the viscoelastic response of liquid water on short timescales, where the hydrodynamic description via a Newtonian-fluid model breaks down.

Physicochemical Properties of Potato Starch Nanoparticles Produced by Anti‐Solvent Precipitation

AbstractThis work aims to understand the physicochemical properties of potato starch nanoparticles (SNPs) obtained by anti‐solvent precipitation. Moisture content, water activity, color, morphology, thermal behavior (differential scanning calorimetry), swelling factor, solubility in water, water sorption isotherms, rheological properties, and stability in water are analyzed and compared using native potato starch (PS) as control. The resulting SNPs after anti‐solvent precipitation have a particle size between 50 and 150 nm, smaller than those observed in PS (between 10 and 100 µm). SNPs behave as an amorphous material without gelatinization stage where the swelling factor is drastically reduced, while the solubility increased dramatically at low temperatures when compared with PS. The Guggenheim–Anderson–de Boer model from the isotherms data allows a calculation of the surface area, obtaining values of 105 and 211 m2 g−1 for PS and SNPs, respectively. The high surface area in SNPs is associated with an increase in the proportion of hydroxyl groups active for water adsorption throughout its structure. Both samples show Newtonian fluid behavior; however, SNPs solutions prove to be much more stable at room temperature than PS solution.

Eco-friendly solvents and their mixture for the fabrication of polysulfone ultrafiltration membranes: An investigation of doctor blade and slot die casting methods

Nonsolvent induced phase separation has been widely used to fabricate polymeric membranes. Common solvents, such as dimethylacetamide (DMAc) and N-Methyl-2-pyrrolidone (NMP), are toxic and not environmentally friendly; therefore, eco-friendly alternatives are needed. Eco-friendly solvents, such as Rhodiasolv® PolarClean (PolarClean) and γ-valerolactone (GVL), have been investigated to replace DMAc and NMP at the laboratory scale; however, not extensively at the production scale. In this work, the feasibility of fabricating polysulfone (PSf) ultrafiltration membranes using eco-friendly solvents at laboratory and production scales is investigated. First, it was determined that the addition of GVL to dope solutions of PolarClean could reduce the original preparation time at a rotation speed of 450 RPM by two-thirds, and by three-quarters at 600 RPM. Furthermore, dope solutions exhibit Newtonian fluid behavior. Doctor blade extrusion and a roll-to-roll (R2R) system integrated with slot die casting are used to fabricate the PSf ultrafiltration membranes at laboratory and production scales, respectively, and the resulting membranes are compared structurally, morphologically and operationally.The chemical structure of membranes is not affected by the use of different solvents or by the differences in fabrication scale. On the other hand, cross-sectional images show that the structures of the membranes are different, most likely due to differences in diffusion rates between the different solvents/co-solvents into the nonsolvent, water. Furthermore, it has been observed that the roughness values of the membranes relative to the fabrication process is different, possibly due to differences in the required evaporation time. All membranes display similar operational parameters, i.e., flux decline, permeability and recovery, during bovine serum albumin (BSA) filtration. Therefore, this study shows that PSf membranes fabricated using eco-friendly solvent mixtures are comparable to traditional membranes, cast using petroleum-derived solvents, and are scalable using slot die casting on a R2R.

Flow morphology of two-phase fluid in co-axial capillaries: Numerical simulation

The dynamic behavior of two-phase Newtonian fluid in co-flow coaxial capillaries was studied numerically. It was found that morphology of the dispersed phase is uniquely described by three non-dimensional parameters as capillary numbers and ratio of Reynolds numbers of the fluid components.

Preparation and Performance Evaluation of Polymeric Microspheres Used for Profile Control of Low-Permeability Reservoirs

To improve in-depth profile control in a low-permeability reservoir, polymeric microspheres were used. A distillation–precipitation polymerization method was adopted to prepare nanometer-sized polymeric microspheres, whose structure, apparent pattern, thermal endurance, particle size, hydration, and swelling capacity were tested and analyzed by a series of techniques, including infrared spectroscopy, scanning electron microscopy, thermogravimetry, high-pressure and high-temperature rheometry, and dynamic light scattering. The prepared polymeric microspheres were copolymerization products of acrylamide, acrylic acid, and methyl methacrylate that were uniformly round with a centralized size distribution. The nanometer-sized microspheres had satisfactory hydration/swelling performance, indicating that they could act as oil displacement profile control agents. With the increase of shear rate, the apparent viscosity of the polymeric microspheres was significantly reduced, and the fluid possessed a pseudoplastic behavior. When the shear rate was 100–1000 s−1, the fluid demonstrated a Newtonian fluid behavior. After the polymeric microspheres were hydrated, the particle size distribution curve shows a normal distribution, reaching a maximum swelling size of 21.3 times that of the original microspheres. The plugging performance and deformability of the polymeric microspheres gradually enhanced with swelling time, which makes the microspheres effective pore channel plugging agents for delivering a better in-depth profile control effect in rock cores with lower permeability. The core flooding test showed that, for the heterogeneous core with a permeability of 10 μm2, polymer microspheres have good plugging effect.

Mechanical, rheological and thermal properties of montmorillonite-modified polyhydroxybutyrate composites

Polyhydroxybutyrate (PHB), a bio-derived and biodegradable polyester, has the potential to be a substitute for traditional polymers. PHB was modified with montmorillonite (MMT), a nanoclay, with the aim of improving its mechanical properties. The clay dispersion, mechanical, rheological and thermal properties of untreated and acid-treated MMT-modified PHB nanocomposites were investigated. Nanocomposite specimens at three different clay loading were prepared using extruder and injection moulding machine. Energy dispersive X-ray mapping revealed that nanocomposites with clay content of 3 phr exhibited better dispersion compared to nanocomposites with higher clay content. The mechanical properties of the MMT-modified PHB, such as the tensile and flexural modulus, were enhanced when compared to neat PHB. From rheology, PHB and PHB nanocomposites modified with untreated MMT exhibited Newtonian fluid behaviour in the tested frequency range. However, for nanocomposites modified with acid-treated MMT, shear thinning behaviour was observed at higher clay content. The nanocomposites also exhibited higher complex viscosity compared to PHB. From transmission electron microscopy analysis, exfoliation of the MMT was observed for the treated MMT nanocomposites at all clay loading. MMT-modified PHB has lower melting temperature when compared to neat PHB. Furthermore, it was found that the addition of MMT influenced the crystallisation behaviour of PHB. The presence of acid-treated MMT also reduced the degree of crystallinity with increasing clay content.

Shearing accelerates denaturation of β-lactoglobulin and α-lactalbumin in skim milk during heating

Shearing is an embedded step during thermal processing of milk that can add additional impact on native proteins. Behaviour of native proteins in bovine skim milk was studied at different temperatures (70–100 °C) for 5 min with or without applying a constant shear rate at 1000 s−1. Shear stress generated generally decreased with increase in temperature due to decrease in milk viscosity which displayed a Newtonian fluid behaviour. β-Lactoglobulin (β-Lg) and α-lactalbumin (α-La) denatured rapidly even at low temperature (70 °C) under the shearing and about 25% more of them denatured at 85 °C than those of the non-sheared counterparts. Shearing predominantly induced formation of thiol/disulphide aggregates mainly consisting of β-Lg and α-La, as well other minor whey proteins and caseins. These results highlighted the necessity of assessing impact of shearing on milk proteins when optimising thermal processing conditions.

Numerical simulation of nanofluid turbulent flow in a double-pipe heat exchanger equipped with circular fins

In this study, the thermal and flow characteristics of a nanofluid were evaluated numerically in a circular finned double-pipe heat exchanger. A 3D CFD model was employed to study the effects of nanofluid properties and fin configuration on the friction coefficient, Nu number and thermal performance. The effects of Al2O3 nanoparticles at the volume concentration of 1–2% were considered for both Newtonian and non-Newtonian turbulent flow in the annulus side with an insulated outer surface and constant heat flux inner tube. A numerical analysis is conducted for different values of Re numbers of 5000–100,000, fin heights (1, 2 and 3 mm) and fin pitches (80, 160 and 320 mm). The results showed that the use of circular fin increases the heat transfer 36% and 30% for Newtonian and non-Newtonian nanofluid, respectively. The Nu number was increased by enhancing Al2O3 volume concentration and Re number. A thermal performance evaluation was carried out to study the conflict between heat transfer and pressure drop. Although the simultaneous use of the fins and nanoparticles improves the thermal behavior of Newtonian fluid but decreases the thermal performance for non-Newtonian fluid due to a penalty in pressure drop. Therefore, in this research adding nanoparticles to non-Newtonian fluid is suggested without any inserts in the annulus.

Composição centesimal e comportamento reológico do extrato de aveia (Avena sativa)

O presente estudo tem como objetivo obter o extrato hidrossolúvel da aveia, determinar a sua composição centesimal e o seu comportamento reológico. O extrato hidrossolúvel foi obtido a partir da imersão dos flocos de aveia em água (70 °C) na proporção 1:3 (aveia/água), durante 15 minutos. O extrato foi caracterizado quanto aos seguintes parâmetros: umidade, atividade de água, sólidos totais, cinzas, proteínas, lipídeos, fibras e carboidratos; para leitura da viscosidade foi utilizado um viscosímetro de Brookfield, modelo DVII+Pro utilizando o splidlen nº 2 com as seguintes rotações: 50, 60, 70, 80, 100, 120, 140 rpm. Através da composição centesimal, percebeu-se que o extrato de aveia apresentou um alto teor de água, baixos valores de cinzas e moderados valores de proteínas, lipídeos e fibras; o aumento da velocidade de rotação acarretou um aumento da viscosidade aparente, o que dificulta o escoamento e a troca de calor durante processos térmicos; o extrato de aveia apresentou comportamento de um fluido não newtoniano com características de plástico de Bingham na temperatura analisada neste trabalho. Sendo portanto, uma ótima alternativa como ingrediente para preparações e dietas isentas de lactose e proteína do leite.

Physical and Rheological Characteristics of Hydroxypropyl, Acid‐Thinned Tapioca Starch‐Based Plasma Expander for Blood Volume Replacement

AbstractPlasma expander (PE) is fluid administered to instantly restore intravascular volume after massive blood loss. PEs can be prepared from various types of polymers such as dextran, albumin, and starch derivatives. This study investigates an alternative source of starch for PEs, that is, hydroxypropyl, acid‐thinned tapioca starch (HPS). HPS is dissolved in 0.9% sodium chloride solution at different concentrations (2%, 4%, 6%, 8%, and 10%). The physical and rheological properties (turbidity, pH, colloid osmotic pressure (COP), and viscosity) and storage stability are compared with 6% of hydroxyethyl starch (6% HES 130/0.4). It clearly demonstrates that turbidity, COP, and viscosity of HPS‐based PE increase when the concentration of HPS increases. The pH of the HPS‐based PE is higher than that of the 6% HES 130/0.4. The viscosity of 6% HPS‐based PE is close to 6% HES 130/0.4 that shows a Newtonian fluid behavior. The COP of 8% HPS‐based PE is similar to 6% HES 130/0.4. After storing for 4 weeks, the viscosity of each concentration is of similar value compared to Day 1. Using a hydroxypropyl tapioca starch as PE has more advantages than HES‐based PE, HPS can be prepared more economically and safely, on a commercial scale, than HES.