Viscosity Η0 Research Articles

Investigation of Active-Inactive Material Interdigitated Aggregates Formed by Wormlike Micelles and Cellulose Nanofiber.

In this work, a novel active-inactive material interdigitated aggregates (AIMIAs) structure was constructed by self-assembled wormlike micelles (WLMs) and one-dimensional cellulose nanofiber (CNF). The rheological behaviors and microstructures of the AIMIA systems with different CNF concentrations were investigated by rheometer, cryogenic transmission electron microscopy, and environmental scanning electron microscope. Some key parameters, including zero-shear viscosity (η0), relaxing time (τR), and contour length ( L), were calculated to analyze the changes in the properties of different systems. Meanwhile, a proper mechanism describing the interaction between CNF and WLMs was proposed. Through this work, we expect to deepen the understanding of the AIMIAs structure and widen its application.

A biophysically-defined hyaluronic acid-based compound accelerates migration and stimulates the production of keratinocyte-derived neuromodulators

ABSTRACTHyaluronic acid (HA) preparations are widely used in clinical practice and recent data suggest that commercially available HA-based compounds promote ulcer re-epithelialization and induce pain relief. However, the pathophysiological basis of these effects remains poorly understood. In the present study, we investigated the biophysical, biomolecular and functional properties of a HA preparation combined with a pool of collagen precursor synthetic aminoacids, namely l-proline, l-leucine, l-lysine and glycine (Aminogam®). Hydrodynamic characterization of Aminogam® by size exclusion chromatography-triple detector array (SEC-TDA) revealed an average molecular weight in the range of 700–1700 kDa. Rheological measurements of the 1700kDa Mw lot showed a pseoudoplastic behaviour with a zero-shear viscosity (η0) equal to 90 ± 9 Pa∙s at 25°C and 55 ± 6 Pa∙s at 37°C. Automated time-lapse videomicroscopy studies in a fibroblast-free system demonstrated that 1% (v/v) Aminogam® significantly reduced the healing time of wounded keratinocyte monolayers. In AKGOS assays, Aminogam® stimulated cellular locomotion (chemokinesis) and directional migration (chemotaxis) of keratinocytes. Analysis of microarray data suggested that keratinocytes had a functional neuroendocrine machinery, and this was confirmed by testing the secretion of six neuroactive molecules by ELISA, namely α-MSH, β-endorphins, melatonin, substance P, cortisol, and neurotensin. Interestingly, Aminogam® regulated the production of several neuropeptides, including β-endorphins. In conclusion, our data shed light on the epithelial-dependent mechanisms that underlie the efficacy of Aminogam®, particularly in reference to wound healing and nociception.

Molecular-weight dependence of phase structure and viscosity in a liquid crystalline polyester with strong π–π interaction

ABSTRACTIn this article, the molecular-weight dependence of the phase structure, rheological behaviour and thermal stability of a main-chain liquid crystalline polyester (PBDPS) with strong π–π interaction was investigated in details by differential scanning calorimetry, polarising optical microscopy, wide-angle X-ray diffraction, dynamic oscillatory rheological measurements and thermogravimetric analysis. While the molecular weight of PBDPS is 5.2k, it shows smectic B and smectic A phases prior to isotropic phase. With increasing molecular weight, smectic B phase of PBDPS gradually disappeared. Moreover, the smecitc B to smectic A (Tlc) and smectic A to isotropic (Ti) phase transition temperatures decreased as increased molecular weight. The rheology results suggested that fluid type of PBDPSs changed from Newtonian fluid to pseudo-plastic fluid as the molecular weight of PBDPS increased. In addition, the zero-shear viscosity (η0) of PBDPS showed a power law relationship () with molecular weight of PBDPS. All the PBDPSs showed good thermal stability with an initial decomposition temperature higher than 360°C.

Stability of plane Couette flow of Carreau fluids past a deformable solid at arbitrary Reynolds numbers

The linear stability of the plane Couette flow of both power-law and Carreau fluids past a deformable, neo-Hookean solid is analyzed at arbitrary Reynolds numbers. An algebraic error in the mathematical formulation of the earlier studies (for the power-law fluid) is corrected and is shown to result in quantitative differences in the predictions for the stability of the flow. Due to the lack of a proper (zero-shear) viscosity scale and a time scale for the onset of shear thinning in the power-law model, we show that the stability analysis of the flow yields vastly different scalings for the unstable mode depending on the way the problem is scaled to render it dimensionless. When the deformable solid properties are used to non-dimensionalize, we show that for the unstable modes (the so-called “wall modes” at high Re) Γc∝Re−1(2n+1), while when flow properties are used to non-dimensionalize, Γc∝Re−13 much akin to a Newtonian fluid, where Γ=Vm*η*/G*R* is the dimensionless shear rate in the flow, and Γc denotes the minimum value required for instability. Here, Vm* is the velocity of the top plate, G* is the shear modulus of the solid, R* is the fluid thickness, and η* is the (arbitrary) viscosity scale in the power-law model. Within the framework of the power-law model, it is not possible to discriminate between the two predicted scalings. To resolve this in an unambiguous manner, we used the Carreau model to account for shear thinning and to study its role on the stability of flow past deformable solid surfaces. The Carreau model has a well-defined zero-shear viscosity η0* as well as a time scale λ* that characterizes the onset of shear thinning. For fixed λ*η0*/(ρ*R*2), we show that the unstable wall modes scale as Γc∼Re(1−2n)3 at high Re, thus providing a resolution to the ambiguity in the results obtained using the power-law model. The present work thus shows that, at moderate to high Re, shear thinning has a strongly stabilizing effect on the wall mode instability in flow past deformable solid surfaces.

Demonstration of a Novel Charge-Free Reverse Wormlike Micelle System.

We demonstrate a novel charge-free reverse wormlike micelle (RWLM) consisting of a ternary mixture of a nonionic amphiphilic block copolymer, fatty acid alkyl ester oil, and water under ambient conditions. Nonionic amphiphile tetra-[poly(oxyethylene)-poly(oxybutylene)]pentaerythrityl ether (TEBPE) self-assembled into spheroid-type micelles in nonaqueous media isopropyl myristate (IPM) with viscosity comparable to that of IPM. The addition of water increases viscosity only slightly up to a certain concentration of water and then drastically, demonstrating the sphere-to-wormlike micelle transition as confirmed by small-angle X-ray scattering. Further increase in water decreases the viscosity after attaining a maximum value. The zero shear viscosity (η0) of the 10 wt % TEBPE/IPM system reached the maximum at 2.6 wt % water and ca. 56 Pa·s, which is ∼fivefold higher than that of water. Dynamic rheological measurements on the highly viscous solutions confirmed the viscoelastic behavior and could be described by the Maxwell model. Conductivity, measured in the presence of a conductive probe, 1-ethyl-3-methylimidazolium tetrafluoroborate, was found to be higher for viscous samples compared to the nonviscous samples, suggesting the static percolation caused by the RWLM formation. Decrease in η0 and conductivity beyond a maximum suggests the shortening of reverse micelles. A similar behavior has been observed in other fatty acid alkyl ester oils of different alkyl chain lengths. Note that most of the RWLM systems previously reported are based on phosphatidylcholine (PC). Formulation and structure-properties related to non-PC-based RWLMs have been rarely explored. Non-PC-based RWLMs using chemically stable and low-cost synthetic molecules can be applied not only in pharmaceuticals and cosmetics but also in a wide range of applications including drag reduction agents for nonaqueous fluids and as a template for nanomaterial synthesis.

Dynamic rheological behavior of poly(ether ketone ketone) from solid state to melt state

ABSTRACTHigh performance thermoplastic poly(ether ketone ketone) (PEKK) polymers with various meta phenyl links ratio were investigated by dynamical mechanical analysis. Analyses were carried out in a wide range of temperature from solid state (torsion rectangular mode) to the melt state (torsion parallel plates mode) as function of thermal history and environmental conditions. In the solid state, this study was focused on the secondary relaxations in the vitreous state. A complementary investigation conducted with different poly(aryl ether ketones) allowed us to propose a molecular interpretation of PEKK sub‐vitreous relaxations. In the molten state, storage modulus (G′), loss modulus (G″), storage viscosity (η′), and loss viscosity (η″) were studied to determine zero shear‐rate viscosity (η0) and thermal activation energy Ea. Master curves were built and the shift factor aT was determined. Thermal activation energies were extracted from an Arrhenius model on the shift factor temperature's dependency. Finally, Ea and η0 were determined thanks to the dynamic viscosity fit with Cross model and Cole–Cole representation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46456.

Diblock Copolymers with Similar Glass Transition Temperatures in Both Blocks for Comparing Shear Orientation Processes with DPD Computer Simulations

AbstractThe purpose of this study is the development of phase‐separating diblock copolymer model systems suitable for the comparison between the orientation process under shear and computer simulations of the same process. To do so, the polymer systems have to fulfill certain requirements like similar dynamics of both polymer blocks, which are associated with comparable glass transition temperatures. The development of suitable diblock copolymer systems such as poly(ethyl methacrylate)‐b‐poly(2‐vinylpyridine) or the tuning of already established polymer systems like polystyrene‐b‐poly(2‐vinylpyridine) via copolymerization with 4‐vinylpyridine is essential. Anionic polymerization is used for the sample synthesis to achieve this goal with the lowest possible polydispersity. Soft, coarse‐grained models are used to study the block dynamics in computer simulations. Within the dissipative particle dynamics methods the remaining differences in the block mobility are addressed. The experimentally determined zero‐shear viscosity η0is used to match the simulation results to the synthesized polymer melts.

Unexpected Rheology of Polydimethylsiloxane Liquid Blends

AbstractThe rheological behaviour of polydimethylsiloxane (PDMS) liquid blends has been investigated both in rotational and oscillating mode. Liquid silicone rubbers based on PDMS at low, medium, and high viscosity have been used for low/high or medium/high liquid blends. The flow, viscosity, creep, and stress‐relaxation curves, strain‐spectra of temperature‐ or frequency‐sweep have been determined and the behaviour at slow shear rate investigated in detail. The low/high homologous blend shows an unexpected behaviour: the zero‐shear viscosity η0 is higher, the compliance J 0 lower and viscoelastic moduli G 0, G(t), G′(ω) and G″(ω) higher, with respect to the components and medium/high blend. Moreover, the blend viscosity η(T), G′(T), and G″(T) exhibits an anomalous decreasing trend. The Entanglement Swelling Tube (EST) model is proposed. The nanosized chains swelled the entanglement of the long ones by means of dipolar interactions Si δ +–O δ − in the sites between the blobs of the tube chains, where the free‐volume is highest. The linked entanglements are stabilized and the lifetime lengthened; the entanglement density increases at long deformation times. As the temperature rises, the anomalous behaviour is reduced due to the Entanglement Deswelling‐Solvation mechanism of short chains up to the transition to ordinary behaviour for T = 65 °C.

A new prediction method for the viscosity of the molten coal slag. Part 2: The viscosity model of crystalline slag

The complex chemical composition of coal slag separated out different types and shapes of crystals during the cooling process. The morphology of the crystal in the molten slag influenced the viscosity of the coal slag. The aim of this paper was to obtain the viscosity model of crystalline slag using a new calculation method. The model of the suspension viscosity obtained by the previous study was used to predict the viscosity of molten slag. The correction factor (β) was introduced in the model of the suspension viscosity. The solid phase volume fraction (φ) in the molten slag was calculated by FactSage. The liquid phase viscosity (η0) was fitted by the viscosities of molten slag in high temperature section. Ten kinds of crystalline slags were applied in this study to prove the accuracy of the modified viscosity model. The viscosity of molten slag predicted by the model (CSM) agreed with experiment data.

An alternative method to enhance w/o emulsion stability using modified dimer acid and its application in oil based drilling fluids.

This study presents an alternative method to enhance the emulsion stability of oil based drilling fluids (OBMs). Modified dimer acid (MDA) was synthesized with a molecular structure having two hydrophilic heads and two hydrophobic tails. Theoretically, the adsorption of MDA on an oil–water interface makes it possible to increase hydrogen bonding between water droplets and form three dimensional networks which benefit emulsion stability. The influence of MDA on the stability of base emulsions was studied by visual observation. Then the stabilization mechanism of MDA was analyzed from the micro and macro points of view by morphology study using a cryo-scanning electron microscope (cryo-SEM) and rheological measurements including viscosity vs. shear rates, zero-shear viscosity (η0), and creep and recovery tests. Experimental results showed that a substantial improvement in emulsion stability was visually observed when the MDA concentration was 2 g L−1. From cryo-SEM observation, a honeycomb structure was observed in the emulsion containing 2 g L−1 MDA, which can provide a physical barrier to restrain the movement of water droplets. In comparison with the rheological behaviors of the emulsion without MDA, a remarkably larger zero-shear viscosity, a solid-like behavior and a greater elasticity were observed when 2 g L−1 MDA was present. Finally, the application in OBMs shows that MDA can largely enhance electrical stability (ES) and reduce the filtration volume. The method proposed in the paper could be used to enhance the stability of w/o emulsions in a variety of fields.

Effects of relaxation time and zero shear viscosity on structural evolution of linear low‐density polyethylene in shear flow

ABSTRACTThe purpose of this work is to investigate the precursor formation and crystallization of four different types of linear low‐density polyethylene in shear flow. The aggregation of string‐like structure (precursor) in micrometer scale was observed by polarized optical microscopy. Although the existence of precursors accelerates crystallization, we find that it is unnecessary for the polymer fluid to possess crystalline structures at relatively high temperatures by wide‐angle X‐ray diffraction. The rotational rheometer result suggests that relaxation time is consistent with processes of the precursor formation observed at 120 °C, while zero shear viscosity affects the boundaries of their corresponding processing windows. According to these results, we propose a mechanism that the precursor formation consists of entanglement and relaxation stages. Entanglements preserve the ordered state of polymer chains, while they return to the initially disordered state during the relaxation stage. Under shearing, the polymer chain is oriented along the flow direction, and the degree of chain motion remains limited because the oriented parts are confined by the entanglements (characterized by zero shear viscosity η0) acting as slip‐links. However, some chain motions and relaxation (characterized by terminal relaxation time τ) can still take place during this stage. Afterwards, the polymer chain becomes disordered and some entanglements disappear. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46053.

Wormlike micelles constructed by a highly water-soluble carboxylate surfactant containing a phenoxy and nonionic surfactant

Limited wormlike micelles were formed from anionic surfactants, especially for carboxylate surfactants due to their poor solubility. As we all know sodium hexadecanoate (C16Na) has a higher Krafft point (60°C). Introducing a phenoxy at α-position of C16Na, a new carboxylate surfactant, sodium 2-phenoxyhexadecanoate (C16phNa), was synthesized. And the aqueous solution of C16phNa could keep water-like even at a concentration of 2M at 25°C. Wormlike micelles were successfully constructed by adding tri(oxyethylene) monododecyl ether (C12EO3) into the dilute solution of C16phNa. Steady state and dynamic rheological measurements were used to investigate the viscoelasticity of C16phNa/C12EO3 wormlike micellar solution. The results show zero shear viscosity (η0) and relaxation time (τRmax) increase at first and then decrease with the increasing concentration of C16phNa or ratio of C12EO3 and C16phNa. The value of η0 in the system could reach 2194.4Pa·s. In addition, η0 is extremely dependent upon the concentration of C16phNa. And the value of exponents between the η0 and concentration is 13.1, 20.2 and 18.3 for a 1:1, 1:1.5 and 1:1.8 system of C16phNa and C12EO3, respectively, which is rather large. Cyro-TEM gave a direct image of wormlike micelles of the system. The present systems enrich the contents of anionic wormlike micelles systems.

Effect of frying on the pasting and rheological properties of normal maize starch

Normal maize starch (NMS) with various water content was subjected to high temperature in the oil phase to mimic the frying process. The structure and physicochemical properties of the fried starchy samples were investigated. Frying induced the reduction in the swelling power, solubility, the amount of leached amylose, and the molecular weight of starch. Rapid visco-analysis (RVA) revealed the partial gelatinization and limited swelling of starch granules after frying treatment. The effect of frying on the pasting properties of starch was dependent on the water content. Creep curves were fitted with the Burgers model and results showed that the fried samples exhibited higher values of instantaneous creep compliance (J0) and viscoelastic creep compliance (Jm), whereas lower values of zero-shear viscosity (η0) as compared with those of native NMS. The low storage modulus (G′) and low loss modulus (G″) form dynamic viscoelasticity measurements indicated that the fried starch pastes exhibited viscoelastic properties that are inferior to those of native NMS paste. Flow state tests showed that fried starch pastes were less thixotropic than was native NMS. Present work confirmed the inhibitory effect of frying on starch granule swelling and starch molecules leaching. The formation of gelatinization layer near the surface of starch granules and the possible molecular degradation during frying were hypothesized to be responsible for the alterations of the pasting and rheological properties of starch.

Structural relaxation of lead and barium-free crystal glasses

The structural relaxation of Na2O–K2O–CaO–ZrO2–SiO2 (NKCZ), Na2O–K2O–ZnO–ZrO2–SiO2 (NKzZ), Na2O–CaO–ZnO–ZrO2–SiO2 (NCzZ), K2O–CaO–ZnO–ZrO2–SiO2 (KCzZ), and Na2O–K2O–CaO–ZnO–ZrO2–SiO2 (NKCzZ) glasses were studied by thermomechanical analysis. The structural relaxation was described by the Tool–Narayanaswamy–Mazurin model (TNMa). The relaxation function of Kohlrausch, Williams, and Watts (KWW) was used. The parameters of relaxation model were calculated by nonlinear regression analysis of thermodilatometric curves measured under cyclic time–temperature regime by thermomechanical analyzer under the constant load. The values of the exponent b of the KWW equation, modulus K, limit dynamic viscosity η 0 of the Mazurin’s expression for relaxation time, and constant B of the Vogel–Fulcher–Tammann viscosity equation were optimized. It was found that TNMa relaxation model very well describes the experimental data. A more detailed analysis of the obtained results showed that the equimolar substitution of SiO2 by ZrO2 (i.e., the increase of the ZrO2 content in the glass) decreases the parameter b, therefore the continuous distribution of the relaxation times spectrum is widening. A wider spectrum of relaxation times was obtained even in the case of substitution of ZnO for CaO and K2O for Na2O. Substitution of ZrO2 for SiO2 decreases the dynamic viscosity limit η 0 that corresponds to an activation energy increase of temperature dependence of isostructural viscosity. Increased content of ZrO2 in the glass caused the increase of the value of the modulus K.

Rheological characterization of vinal gum, a galactomannan extracted from Prosopis ruscifolia seeds

Prosopis ruscifolia (or vinal tree) is an abundant plant from Argentina semiarid areas, whose seeds contain a galactomannan type interesting gum: vinal gum. The aim of this work was to analyze the rheological behavior of vinal gum suspensions and the consequences of its interactions with commercial gums widely employed in the food industry. Vinal gum aqueous suspensions were in good agreement with the Cox-Merz rule at concentrations lower or equal to 1% (w/w), which establishes an empirical relationship between complex and apparent viscosity. The flow curves of vinal gum could be defined only by two parameters -Newtonian viscosity (η0) and strain rate (γ˙0.1)- and the shear-thinning behavior of vinal gum complied with the generalized curve for other polysaccharides. In mixtures with xanthan gum, vinal gum exhibited a synergistic relationship on its elastic behavior (at a total gum concentration of 1% (w/w)). On the other hand, vinal gum showed no synergism with κ-carrageenan or sodium alginate at the same total concentration of polymer. Apparent viscosity of vinal gum aqueous suspensions showed Arrhenius type dependence with temperature, as other galactomannans. The rheological behavior was not dependent on shear time, and the thickening power of vinal gum was slightly affected by pH and ionic strength changes. The present work provides detailed information on rheological characteristics of a non-traditional galactomannan extracted from an abundant and available source, being a starting point for possible applications of vinal gum as thickening and/or stabilizing agent in food, pharmaceutical, paper, textile, oil and cosmetics industries.

Predicting melt rheology for hot-melt extrusion by means of a simple Tg-measurement.

The feasibility of predicting melt rheology by using the glass transition temperature (Tg) of a desired amorphous solid dispersion (ASD) for hot-melt extrusion (HME) and other melt based processes is presented. Three groups of three different active pharmaceutical ingredients (APIs) or plasticizer/copovidone mixtures, with identical glass transition in rheological testing, were used. Their rheological behavior as a function of temperature and frequency were analyzed by means of small amplitude oscillatory shear (SAOS) on an oscillatory rheometer. The zero-shear viscosity (η0) identified at 150°C was compared to Tg, measured by differential scanning calorimetry (DSC) and SAOS. A strong correlation between η0 and Tg was identified, independent of the API or plasticizer used to achieve Tg of the mixture. To evaluate and rate the discrepancy in η0 of the different mixtures at same Tg, hot-melt extrusion trials were conducted to measure torque and mean residence time. In this paper, carbamazepine, dipyridamole, indomethacin, ibuprofen, polyethylene glycol (PEG 1500) in vinylpyrrolidone-vinyl acetate copolymer (copovidone) as matrix polymer were used.

Comparative study of the viscoelastic micellar solutions of R16HTAC and CTAC in the presence of sodium salicylate

A comparative study of the rheological properties of cationic surfactants 3-hexadecyloxy-2-hydroxypropyl trimethyl ammonium chloride, referred to as R16HTAC, and cetyltrimethylammonium chloride (CTAC) in the presence of sodium salicylate (NaSal) have been carried out by using steady state and frequency sweep rheological measurements. The zero-shear viscosities η0 all appears maximum value in the especial point where the molar ratio of surfactant and NaSal is 1 for both surfactants (R16HTAC and CTAC). The characteristic parameters for two systems are discussed on the basis of their different molecular structures, which leaded to higher viscoelasticity for R16HTAC mixed solution than CTAC. The microstructure of the formed micelles and strong network for R16HTAC/NaSal mixed aqueous solution has been confirmed by transmission electronic microscopy and 1H NMR technology. The antimicrobial properties and toxicity of two surfactants were also investigated.

Highly Viscoelastic Reverse Wormlike Micellar Systems from a Mixture of Lecithin, Polyglycerol Fatty Acid Monoesters, and an Oil.

We report new lecithin reverse wormlike micelles with high viscoelasticity formed using lecithin/polyglycerol fatty acid monoester (PGLFA)/oil systems. In this study, the influence of the amphiphilicity (i.e., hydrophile-lipophile balance, HLB) of PGLFA on the phase behavior and rheological properties of reverse wormlike micelles was investigated in detail. PGLFAs with degrees of polymerization of polyglycerol varying between 6-40 and constituent fatty acids with chains between 6-18 carbon atoms long were used. Partial phase diagrams of the lecithin/PGLFA/n-decane systems indicated that the appropriate PGLFA could change the lecithin/oil solution into a highly viscoelastic solution comprising reverse wormlike micelles. Rheological measurements showed that all systems that formed reverse wormlike micelles exhibited an unusual phenomenon called "shear-thickening". Furthermore, reverse wormlike micelles grew as the PGLFA concentration increased and the zero-shear viscosity (η0) of the solution rapidly increased. Our results indicate that the magnitude of the maximum η0 depends on the degree of polymerization of the constituent polyglycerol in the PGLFA, while the size of the reverse micellar region and the highly viscous region in the phase diagram depends on the HLB value of the PGLFA.

Viscoelastic Properties of Polymer Modified Bitumen in Warm Mix Asphalt Technology in Terms of Ageing

The paper presents the influence of ageing on the viscoelastic properties of the polymer modified bitumen (PMB) in WMA technology. The base bitumen was PMB 45/80-65. Fischer-Tropsch synthetic wax (SW) and the liquid surface active agent (FA) ware used as a bitumen viscosity-reducing modifiers. All properties of binders have been determined before ageing (NEAT) and after long-term ageing (RTFOT+PAV). The research area includes the study basic properties (softening point and Fraass breaking point) and rheological characteristics (zero shear viscosity ZSV, complex viscosity η0 and rutting factor G*/sinδ). It was found that fatty amine additive works as a ageing inhibitor. The ageing process revealed degradation process in polymer. This phenomenon is more explicit in the bitumen modified with wax than the fatty amine.

Structure impact of two galactomannan fractions on their viscosity properties in dilute solution, unperturbed state and gel state

Two fractions of carob galactomannans (GM25 and GM80) were extracted at respectively 25°C and 80°C from crude locust bean gum. Those fractions having slightly different chemical structures, previously characterized, were studied for their viscosity properties over a wide range of concentrations: diluted solution, unperturbed state and gel state. For each of the physical properties, links to the chemical fine structure could be established, expanding knowledge on the topic: in dilute solution, GM25 is more soluble in water while GM80 seems to tend to self-association due to its structure as highlighted by intrinsic viscosity measurements ([η]GM25=9.96dLg−1 and [η]GM80=4.04dLg−1). In unperturbed state, initial viscosities η0 were more important for GM80 fractions at 1% and 2% due to greater hyperentanglements (η0(GM80,1%)=9.9Pas; η0(GM80,2%)=832.0; Pa.s η0(GM25,1%)=3.1Pas; η0(GM25,2%)=45.1Pas). In gel state, hydrogels obtained from GM80 were also stronger (hardness GM80 (2%)=0.51N and hardness GM25 (2%)=0.11N), suggesting a much more important number of junction areas within the gel network. The findings discussed herein demonstrate the potential for new applications.