Linear Viscoelastic Regime Research Articles

Use of Multi-Anionic Sodium Tripolyphosphate to Enhance Dispersion of Concentrated Kaolin Slurries in Seawater

This research aims to analyze the impact of sodium tripolyphosphate (STPP) as a rheological modifier of concentrated kaolin slurries in seawater at pH 8, which is characteristic of copper sulfide processing operations. The dispersion phenomenon was analyzed through chord length measurements using the focused beam reflectance measurement (FBRM) technique, complementing size distributions in unweighted and square-weighted modes. The reduction of the rheological properties was significant, decreasing from 231 Pa in a reagent-free environment to 80 Pa after the application of STPP. A frequency sweep in a linear viscoelastic regime indicated that by applying a characteristic dosage of 0.53 kg/t of STPP, the pulp before yielding increases its phase angle, which increases its liquid-like character. Measurements of the chord length verified the dispersion of particles, which showed an apparent increase in the proportion of fine particles and a reduction of the coarser aggregates when STPP was applied. Measurements of the zeta potential suggested that the high anionic charge of the reagent (pentavalent) increases the electrostatic repulsions between particles, overcoming the effect of cations in seawater. The results are relevant for the mining industry, especially when the deposits have high contents of complex gangues, such as clays, that increase the rheological properties. This increases the energy costs and water consumption needed for pumping the tailings from thickeners to the tailing storages facilities. The strategies that allow for the improvement of the fluidity and deformation of the tailings generate slack in order to maximize water recovery in the thickening stages.

Payne effect of carbon black filled natural rubber nanocomposites: Influences of extraction, crosslinking, and swelling

Rubber nanocomposites experiencing dynamic shears at large strain amplitudes (γ) exhibit the nonlinear Payne effect featured by decays of storage and loss moduli (G′ and G″) or by G′ decay accompanied with G″ overshoot near a critical strain amplitude. The occurrence of the Payne effect has been assigned to damages of “filler network” and rubber-filler interfacial interactions for a long time and to Rouse dynamics of rubber chains recently. To solve the dispute, influences of extraction, crosslinking, and paraffin swelling on the Payne effect of carbon black filled natural rubber nanocomposites are investigated systematically. Master curves of G′ as a function of γ could be always created, and overshoot of G″ in the filled vulcanizates weakens with increasing filler content and intensifies by dilution via paraffin swelling, suggesting that the Payne effect is not mainly rooted in the “filler network” and rubber-filler interfacial interactions. The filler reduces the onset strain amplitude of the Payne effect by amplifying microscopic strain amplitude of the rubber phase, irrespective of whether the matrix is crosslinked or not and whether the crosslinked matrix is swollen or not. Partial removal of bound rubber by compounding the paraffin swollen compounds could lower modulus and eliminate G″ overshoot of the deswollen vulcanizates without influence on the mechanism of G′ decay accompanying Payne effect. The overshoot is found to be closely related to the overall viscous characteristic of the vulcanizates in the linear viscoelastic regime. Provided herein are new insights for recognizing the important roles of the viscoelastic rubber phase on the Payne effect of the nanocomposites.

Evolution of the electrical resistivity at rest and during oscillatory shearing of co‐continuous morphology (PP/PMMA)/MWCNT systems

AbstractIn this work, a modified parallel‐disks configuration on a strain‐controlled ARES rheometer (TA Instrument) was used to study the evolution of the electrical resistivity at rest and during oscillatory shearing of a co‐continuous immiscible polymer blend morphology based on polypropylene and /polymethyl(methacrylate) (PP/PMMA) in which various amounts (0–3 wt%) of multiwall carbon nanotubes (MWCNT) were added. The co‐continuity of both PP and PMMA phases allowed the buildup of a conductive network due to the preferential localization of the conductive MWCNT at the interface between PP and PMMA. Under a stepwise increase of the oscillatory strain amplitude below a critical value (γc = 6.3%), a significant decrease in the electrical resistivity was observed for MWCNT concentrations above the percolation threshold (0.3 wt%) due to the conductive paths induced by both thermal (Brownian) motion and oscillatory shearing. However, for deformation amplitudes higher than γc, the resistivity increased due to the destruction of the MWCNT paths induced by the large deformation imposed on the PP/PMMA interface. These observations were also confirmed by the evolution of the storage modulus (G′) which remained constant for γc < 6.3% (linear viscoelastic regime), while the values decreased above γc due to the destruction of the system's morphology.

Mapping the texture of plant protein blends for meat analogues

The development of next-generation meat analogues can be accelerated by in-depth knowledge of the rheological properties of dense biopolymer blends. Blends comprising plant proteins such as pea protein isolate or soy protein isolate combined with wheat gluten can be used to create a wide range of structures. The objective of this study is to demonstrate the use of texture maps to systematically show the rheological properties of plant proteins under conditions relevant to processing of meat analogue products. The first texture map was constructed by plotting the stress and strain at the end of the linear viscoelastic regime of the strain sweeps and a second map was based on the stress and strain at the crossover point of those sweeps. Next, a colour scheme was used to visualize the relative importance of the viscous and elastic contributions as a function of the strain amplitude and different ratios of each protein in the blend. The maps and schemes showed that heating induced elasticity. In pea protein–wheat gluten blends, lower strain, stress and elasticity values were obtained for pea compared with wheat gluten. In soy protein–wheat gluten blends, the texture properties were almost similar for the two components. Soy protein–wheat gluten blends are tougher and more elastic than pea protein–wheat gluten blends.

Friction of lubricated hydrogels: Influence of load, speed and lubricant viscosity

Agarose hydrogels are used to study the tribological response of hydrogel materials. We demonstrate that the dynamic frictional behaviour of agarose hydrogels is influenced by their mechanical properties, lubricant viscosity and applied load. Within the linear viscoelastic regime of the hydrogels, we find the Stribeck-type framework proposed previously for elastomers and other viscoelastic materials describes their tribological behaviour and dependency on lubricant viscosity. However, this breaks down when sufficient stress in the contact is applied so that the hydrogel undergoes yielding (i.e. elastic-plastic deformation). As a result, we find that the friction- normal load relationship differs from the classic trend (F ~ W2/3) observed in elastomers above finite loads. Conventional interpretations of the friction associated with hydrogels should be revised with consideration for the non-linear deformation of the hydrogels. We suggest that theories on viscoelastic lubrication are generally applicable to hydrogels within their linear viscoelastic regime, and propose a conceptual model that considers the effects of bulk mechanical properties and measurement conditions including lubricant viscosity, measuring geometry, speed and load.

Validation of partial time-temperature superposition principle in thermorheologically complex asphalts

This study aims to validate the applicability of the partial time–temperature superposition principle to simulate the behavior of thermorheologically complex modified asphalts. Six different asphalts were used to analyze this complexity using dynamic mechanical tests within the linear viscoelastic regime. The results showed that the complexity of polymer-modified asphalts is attributable to the formation of an entanglement network generated during the modification via physical and chemical processes based on the polymer type. It was also found that this network increased the modulus and decreased the viscous component at high temperatures, thereby improving the performance of modified asphalts. Despite the observed complex behavior, smooth and continuous master curves were obtained for viscoelastic properties different from the phase angle in frequency and time domains. For the phase angle and loss modulus master curves, the overall trend of the disjointed isothermal curves was simulated using a rheological model.

Chain structure, linear viscoelasticity and extensional rheology of poly(4‐vinyl biphenyl‐stat‐styrene) statistical copolymers

AbstractA series of statistical copolymers of 4‐vinylbiphenyl and styrene were prepared via free radical polymerization to investigate the effect of the comonomer ratio on their microstructure and rheological properties. The glass transition temperature of the copolymers follows a nonlinear monotonic decreasing dependence with increasing styrene content which is well described by the Gordon‐Taylor equation. WAXS measurements reveal that both the backbone to backbone and the inter‐phenyl distances (d1 and d2, respectively) are decreasing functions of the styrene content in the copolymers. The apparent monomeric friction coefficient, calculated from dynamic frequency sweeps in the linear viscoelastic regime, decreases exponentially with the styrene content in the copolymer. We postulate that the strong effect of the copolymer composition on the friction coefficient is due to the larger overlapping distance between phenyl rings of adjacent polymer chains (doverlap), giving rise to stronger aromatic π–π interactions, which in turn results in stronger friction between adjacent chains. The increase in doverlap and monomeric friction coefficient also leads to a significant increase in the extensional strain hardening measured during extensional startup flow measurements.

Nonlinear Rheology of FENE Dumbbell with Friction-Reduction: Analysis of Brownian Force Intensity through Comparison of Extensional and Shear Viscosities

Normalized extensional and shear viscosities, ηE/ηE0 and η/η0 with the subscript “0” standing for quantities in the linear viscoelastic (LVE) regime, are theoretically analyzed for the FENE-dumbbell in the presence of isotropic friction-reduction under flow. The basic parameters in the analysis are the friction reduction factor rζ = ζsf/ζeq, FENE factor rκ = κsf/κeq, and the Brownian force intensity factor rB = Bsf/Beq, with ζ and κ being the bead friction coefficient and spring strength of the dumbbell, B denoting the intensity of the Brownian force acting on the bead, and the subscripts “sf” and “eq” standing for the quantities under steady flow and at equilibrium, respectively: Beq = 2ζeqkBT with kBT being the thermal energy, according to the fluctuation-dissipation theorem valid at equilibrium. The normalized viscosities were found to be analytically expressed as ηE/ηE0 = (rB/rκ){1−2(rζ/rκ)Wi}−1{1+(rζ/rκ)Wi}−1 and η/η0 = (rB/rκ), with Wi being the Weissenberg number defined with respect to the LVE relaxation time. Both ηE/ηE0 and η/η0 are proportional to the rB factor, so that comparison of these quantities allows us to characterize the intensity of the Brownian force Bsf under flow. For example, for a test case of power-law decay of rζ with Wi, the above expressions of ηE/ηE0 and η/η0 suggested a relationship 2ζsfkBT < Bsf < 2ζeqkBT View PDF for the rest of the abstract

Luffa Cylindrica as a durable biofiber reinforcement for epoxy systems

Luffa Cylindrica (LC) is the dried fruit of a sponge-type plant belonging to Curcubitacea family. Recent advancements in hierarchical and lightweight structures have aroused interest in this natural fibrous material for illustrating an extraordinary multi-porous architecture of high anisotropy and low density. To the extent of its biodegradable nature, such a structure is potentially apt to replace conventional porous-like composites for low-energy absorbing and material reinforcing applications. In order to investigate its candidacy as a long-term sustainable reinforcement, a LC layer is impregnated with an epoxy resin (ER) system and subjected to tensile creep tests within the linear viscoelastic regime. Specimens loaded with 30% weight fraction of LC fibers are tested at four stress levels corresponding to 5%, 8%, 10% and 15% of the static tensile strength σu of the composite. The viscoelastic response of the LC/ER composite is found improved with respect to that of the pure polymer. This improvement is reflected to the creep strain and compliance that decreased by 30%. The creep results are subsequently probed by means of the four–parameter (Burger) analytical model to gain insight on the viscoelastic behavior.

Development of hydroxyapatite reinforced alginate–chitosan based printable biomaterial-ink

This study reports synthesis of sodium alginate/ chitosan/ hydroxyapatite (HAp) based biomaterial-ink. An ionic interaction between polyanionic alginate and polycationic chitosan has been observed that forms a physical gel. The dispersion of HAp has been achieved through ultra-sonication, and stability of HAp in the hydrogel system has been achieved through hydrogen bonding with chitosan. Post printing crosslinking has been carried out with a 10 w/v % aqueous calcium chloride (CaCl2) solution. The combinations of biomaterial-ink have been characterized through Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), Scanning Electron Microscope (SEM), contact angle measurements. Further, the inks were characterized to estimate the printability and rheological responses. ATR-FTIR study confirms the ionic interaction between alginate and chitosan and identifies the presence of HAp in the biomaterial-ink. SEM morphology depicted the post-printing shape retention ability of the bioprinted constructs and revealed the structure’s rough morphology. All the biomaterial-ink combinations depicted hydrophilic nature as confirmed by the contact angle measurements. Rheological studies of the printable ink with hydroxyapatite revealed shear thinning properties and acceptable viscosity, essential for extrusion during bioprinting. The biomaterial-ink comprised only sodium alginate, and chitosan also displayed shear thinning abilities and showed lower working viscosity resulting in poor printability. The addition of hydroxyapatite to the hydrogel revealed acceptable post-printing structural stability. However, beyond 0.2% by weight of HAp imparts brittleness in the final structure. The linear viscoelastic regime, elastic modulus, and viscous modulus of the inks have been determined through the oscillatory strain sweep test. Creep recovery study, essential for predicting material behaviour immediately after ejection from the nozzle, indicated the material’s viscoelastic behaviour. The power law model has been used to estimate the flow index that predicted shear thinning abilities of the biomaterial-ink, and a correlation between the experimental and theoretical model was established. Herschel–Bulkley empirical model was used to determine yield stress (minimum stress required for extrusion from the nozzle) of the biomaterial-ink. Rheological studies and printability studies indicated Ink 5% 2% 0.1% as a promising combination for tissue engineering applications.

A nonlinear dynamic model of magnetorheological elastomers in magnetic fields based on fractional viscoelasticity

As smart materials, magnetorheological elastomers (MREs) have been broadly applied in the field of intelligent structures and devices. In order to mathematically represent the dynamic behavior in a wide range of strain amplitude, excitation frequency and magnetic field; a nonlinear model with a fractional element was developed for MREs in a linear viscoelastic regime. The identification of model parameters was realized through fitting experimental data of dynamic moduli measured in shear mode, and the identified parameters exhibited good repeatability and consistency to reflect the rationality of this nonlinear dynamic model. Considering material elasticity and viscosity, the dependence of model parameters on strain amplitudes and magnetic fields was analyzed to interpret the dynamics of MREs. The fitted results displayed an excellent agreement with the experimental results on the dependence of dynamic moduli on strain amplitudes and magnetic fields. Using the predictor-corrector approach, predicted results on the stress-strain hysteresis loop were calculated based on identified parameters to further validate the proposed model by comparing with experimental results and predicted results of the revised Bouc-Wen model. This proposed model is expected to facilitate the dynamic analysis and simulation of MRE based vibration systems with a high precision accuracy.

Creep behaviour of elastomeric nanocomposites by flat punch indentation: Influence of graphene modification and content

Creep can be understood as the resistance of a material to a continuous stress and represents an important property for engineering design. The creep behaviour of a series of nanocomposites with electromechanical applications based on a thermoplastic elastomer, poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS), and small amounts of graphene has been explored using cylindrical flat punch depth-sensing indentation. Special attention is paid to the influence of the nature of the polymer brushes (polyethylene or polystyrene) attached to the graphene surface. Common methodologies for indentation creep analysis are critically examined and brought together to provide a comprehensive picture of creep deformation. It is found that graphene significantly reduces the creep rate and this is most significant under viscoplastic deformation than in the linear viscoelastic regime. Most interesting, polyethylene branches reduce visco-elastic-plastic flow in a more effective manner and this is attributed to the selective interaction of the filler with the matrix chains.

Silk Protein Solution: A Natural Example of Sticky Reptation.

Silk is one of the most intriguing examples of biomolecular self-assembly, yet little is understood of molecular mechanisms behind the flow behavior generating these complex high-performance fibers. This work applies the polymer physics of entangled solution rheology to present a first microphysical understanding of silk in the linear viscoelastic regime. We show that silk solutions can be approximated as reptating polymers with “sticky” calcium bridges whose strength can be controlled through the potassium concentration. This approach provides a new window into critical microstructural parameters, in particular identifying the mechanism by which potassium and calcium ions are recruited as a powerful viscosity control in silk. Our model constitutes a viable starting point to understand not only the “flow-induced self-assembly” of silk fibers but also a broader range of phenomena in the emergent field of material-focused synthetic biology.

The rheological properties and gelation kinetics of corn starch/bovine serum albumin blend

The rheological properties and gelation kinetics of corn starch (CS)/bovine serum albumin (BSA) blends were investigated using the mass ratio of [CS]/[BSA] of 0, 0.5, 1, 2, and 3. The results from the temperature ramp and time sweep tests within linear viscoelastic regime showed a decrease in the gelation temperature (Tgel) and gelation time (tgel) of the BSA with increasing the mass ratio of [CS]/[BSA]. A significant decrease in the Tgel and tgel occurred at 5 wt.% BSA with [CS]/[BSA] = 3, where about 12 °C and 11 min drops in the Tgel and tgel were recorded. At the molecular scale, the decrease in the Tgel and tgel with increasing the mass ratio of [CS]/[BSA] was attributed to the breaking down of hydrogen bonding sites in the CS molecules with increasing temperature, and thereby allowing the hydroxyl group to engage in intermolecular hydrogen bonding with the BSA polar amino acid residues. The hydrogen bonding in addition to other non-covalent forces appeared to strengthen the microstructure of the CS/BSA gel as confirmed by the dynamic frequency sweep test. The frequency sweep test also showed that the value of the storage modulus (G′) at [CS]/[BSA] = 3 was about 10 to 103 orders of magnitude larger than its value recorded for the pure BSA. Kinetically, the gelation process was well modelled by the temperature dependency of reaction rate constant as represented by the Arrhenius equation. If interpreted in terms of the energy required to attain the gel state, the addition of CS reduced the gel activation energy (Ea) to 153.90 kJ/-mol as against the original value of 268.55 kJ/mol that was observed for the BSA without CS.

Interfacial viscoelasticity and aging effect on droplet formation and breakup

Interfacial rheology of interfaces stabilized by food ingredients has been studied extensively within the limits of small and slow deformations, within the linear viscoelastic regime (LVR). However, in practice, products such as foams or emulsions undergo fast and large deformations during food processes such as chewing. emulsifying, or foaming. In this study, we used capillary break-up and droplet formation to observe and quantify large and fast deformations of such interfaces, in the presence of surface viscoelasticity. We studied the inertial thinning of the liquid neck during drop formation using high-speed imaging. We tested solutions of several surface active molecules, including two low molecular weight surfactants (SDS and Tween 20), two milk proteins (β-Lactoglobulin, Bovine Serum Albumin) and the saponin Escin. Escin showed the most significant effect on the shape of the neck and neck thinning dynamics. Interfacial shear rheology measurements indicated that the unusual breakup observation of Escin solutions was related to the high viscoelastic surface shear moduli. These high moduli, and the resulting more symmetric and shorter neck shape observed for the proteins and Escin, are associated with the formation of solid-like interfacial structures. However, the presence of a viscoelastic interface did not affect the inertial thinning regime, which indicates that the solid structures were broken down locally at the area of minimum radius (Rmin), and affected only the shape outside this region. The results of this work therefore, show that interfacial measurements within the LVR are not entirely representative for fast and large deformations well beyond linearity.

I-Rheo: determining the linear viscoelastic moduli of colloidal dispersions from step-stress measurements.

We report on the application of a Fourier transform-based method, 'i-Rheo', to evaluate the linear viscoelastic moduli of hard-sphere colloidal dispersions, both in the fluid and glass states, from a direct analysis of raw step-stress (creep) experimental data. We corroborate the efficacy of i-Rheo by comparing the outputs of creep tests performed on homogenous complex fluids to conventional dynamic frequency sweeps. A similar approach is adopted for a number of colloidal suspensions over a broad range of volume fractions. For these systems, we test the limits of the method by varying the applied stress across the materials' linear and non-linear viscoelastic regimes, and we show that the best results are achieved for stress values close to the upper limit of the materials' linear viscoelastic regime, where the signal-to-noise ratio is at its highest and the non-linear phenomena have not appeared yet. We record that, the range of accessible frequencies is controlled at the higher end by the relative weight between the inertia of the instrument and the elasticity of the complex material under investigation; whereas, the lowest accessible frequency is dictated by the extent of the materials' linear viscoelastic regime. Nonetheless, despite these constrains, we confirm the effectiveness of i-Rheo for gaining valuable information on the materials' linear viscoelastic properties even from 'creep ringing' data, confirming its potency and general validity as an accurate method for determining the material's rheological behaviour for a variety of complex systems.

Interfacial rheology and relaxation behavior of adsorption layers of the triterpenoid saponin Escin

HypothesisEscin, a monodesmosidic triterpenoid saponin, was shown previously to form viscoelastic interfaces with a very high dilatational and surface shear storage modulus. This is expected to be due to the arrangement of Escin into 2D disordered soft viscoelastic solid interfacial structures, which results in turn in a distribution of relaxation times. ExperimentsThe responses to dilatational and surface shear deformations of Escin-stabilized air-water interfaces were studied, both in the linear viscoelastic (LVE) and non-linear (NLVE) regime. Step relaxation and amplitude sweeps were performed in dilatation experiments. For surface shear, amplitude sweeps and creep recovery experiments were performed. FindingsEscin stabilized-interfaces displayed a highly non-linear behavior in dilatation as seen in the Lissajous plots. In large oscillatory shear the Lissajous curves had a rhomboidal shape, indicating intracycle yielding and recovery, typical of glassy systems. The relaxation of the interface showed stretched exponential behavior, with stretched exponents typical of disordered solids with dynamic heterogeneity. The use of surface rheological measurements beyond the commonly measured LVE regime clearly has provided new insights into the behavior of these interfaces and their microstructure. These results highlight the need to reconsider other complex interfaces as disordered solids and not as 2D homogenous viscoelastic fluids.

Numerical simulation of the fluid dynamics in a 3D spherical model of partially liquefied vitreous due to eye movements under planar interface conditions

Partially liquefied vitreous humor is a common physical and biochemical degenerative change in vitreous body which the liquid component gets separated from collagen fiber network and leads to form a region of liquefaction. The main objective of this research is to investigate how the oscillatory motions influence flow dynamics of partial vitreous liquefaction (PVL). So far computational fluid dynamics modeling of the PVL has not yet been well studied. To this end, a spherical model of the vitreous is subjected to harmonic motion and the numerical simulations are performed for various planar interface conditions in linear viscoelastic regimes. A numerical solver is developed in the OpenFOAM toolbox which is based on finite volume method and uses the PIMPLE algorithm and the dynamic mesh technique. This solver also uses modified classic volume-of-fluid approach to capture the interface effects and dynamic characteristics of two-phase viscoelastic-Newtonian fluid flow. The numerical model is validated by comparing the obtained results with the analytical solution which excellent agreement was observed. The results showed that the intensity of secondary flow in the vertical direction was much higher for the PVL with a higher liquefied fraction. Also, the obtained maximum stresses were dependent on the liquefied fraction of the PVL and located on the equatorial plane at the cavity wall near the interface layer and within the vitreous gel.

Is density enough to predict the rheology of natural sediments?

Mud is a cohesive material which contains predominantly clay minerals, water, organic matter and some amounts of silt and sand. Mud samples can have complex rheological behaviour, displaying viscoelasticity, shear-thinning, thixotropy and yield stress. In this study, influence of organic matter on the rheological behaviour of different mud samples having similar densities is investigated. Four samples, collected from different locations and depths of Port of Hamburg (Germany) were selected. Two samples with the density of about 1210 kg/m3 and two samples with the density of about 1090 kg/m3 were analysed by different rheological tests, including stress ramp-up tests, flow curves, thixotropic tests, oscillatory amplitude and frequency sweep tests. Two yield stress regions (with two yield stress values stated as “static” and “fluidic” yield stresses) were identified for all the samples, and these regions, corresponding to a structural change of the samples were significantly different from sample to sample due to the differences in organic matter content. For lower density samples, the ratio of fluidic to static yield stress increased from 3 to 4.4 while it increased from 4.4 to 5.2 in case of higher density samples, by increasing the organic matter content. The thixotropic studies showed that the mud samples having lowest organic matter content (VH and KBZ) exhibit a combination of thixotropic and anti-thixotropic behaviours. The results of frequency sweep tests revealed the solid-like character of the mud within the linear viscoelastic regime. Mud samples having higher organic matter content (RV and RT) had a higher complex modulus (417 Pa and 7909 Pa) than the ones with lower organic matter content (13 Pa and 1774 Pa), for a given density. This study demonstrated that the density only is not a sufficient criterion to predict the rheology of different mud. Furthermore, even small amounts of organic matter content change significantly the mud rheological behaviour.

Rheological behaviour of thermotropic and lyotropic liquid crystalline phases of Guerbet branched chain glycolipids

Glycolipids, being low toxicity, biodegradable and showing surface activity, are a candidate for an alternative surfactant known as biosurfactant. In this study, two Guerbet branched chain glycolipids namely 2-hexyl-decyl-β-d-glucoside (β-Glc-C10C6) and 2-hexyl-decyl-β-d-maltoside (β-Mal-C10C6) were prepared and their mesomorphic behaviours in dry and hydrated conditions were characterized and compared using rheology. These glycolipids possessed the same number of carbons in their alkyl chain but differed in headgroup size. β-Glc-C10C6 exhibited inverse hexagonal phase (H2) in thermotropic but formed inverse bicontinuous cubic phase (V2) of space group Ia3d and Pn3m upon contact with water at different concentration ranges. The self-assembly of β-Mal-C10C6 was dominated by the lamellar phase (Lα) in both conditions. A shear viscosity test indicated that all mesophases formed by these Guerbet glycolipids exhibited shear thinning behaviour. Oscillation measurements were obtained within the linear viscoelastic regime. In general, the viscoelastic studies on the thermotropic H2 (β-Glc-C10C6) and Lα (β-Mal-C10C6) phases showed that the storage modulus (G′) and loss modulus (G″) increased with the frequency, indicating the typical viscoelastic response for non-Newtonian fluid at the selected temperatures. The lyotropic inverse bicontinuous cubic of β-Glc-C10C6 containing different water concentrations showed the dominance of G’ over G” at the range of frequencies and temperatures tested. A similar finding was observed for the lyotropic Lα phase of β-Mal-C10C6 but with a lower magnitude of structural strength.