Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic ... more Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (GIL′= 7.5 Pa at 100 rad s−1 and 298 K). Furthermore, the ionic conductivity (σ0) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10−4 S cm−1 at 298 K. Additionally, we found the Haven Ratio (HR) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room...
Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtain... more Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtained by commercial and monovarietal durum wheat flours (Cappelli and Karalis). Rheological frequency sweep tests were carried out, and the Weak Gel model, whose parameters may be related to gluten network extension and strength, was applied. IR analysis mainly focused on the Amide III band, revealing significant variations in the gluten network. Compared to the other varieties, Karalis semolina showed a higher amount of α-helices and a lower amount of β-sheets and random structures. Spectroscopic and rheological data were then correlated using Partial Least Squares regression (PLS) coupled with the Variable Importance in Projection (VIP) technique. The combined use of the techniques provided useful insights into the interplay among protein structures, gluten network features, and rheological properties. In detail, β-sheets and α-helices protein conformations were shown to significantly aff...
To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sam... more To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sample concentration profile is developed, which increases the sensitivity. The analytes can be characterized by evaluating the phase angle and magnitude.
Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic ... more Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (GIL′= 7.5 Pa at 100 rad s−1 and 298 K). Furthermore, the ionic conductivity (σ0) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10−4 S cm−1 at 298 K. Additionally, we found the Haven Ratio (HR) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room...
Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtain... more Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtained by commercial and monovarietal durum wheat flours (Cappelli and Karalis). Rheological frequency sweep tests were carried out, and the Weak Gel model, whose parameters may be related to gluten network extension and strength, was applied. IR analysis mainly focused on the Amide III band, revealing significant variations in the gluten network. Compared to the other varieties, Karalis semolina showed a higher amount of α-helices and a lower amount of β-sheets and random structures. Spectroscopic and rheological data were then correlated using Partial Least Squares regression (PLS) coupled with the Variable Importance in Projection (VIP) technique. The combined use of the techniques provided useful insights into the interplay among protein structures, gluten network features, and rheological properties. In detail, β-sheets and α-helices protein conformations were shown to significantly aff...
To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sam... more To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sample concentration profile is developed, which increases the sensitivity. The analytes can be characterized by evaluating the phase angle and magnitude.
s of the invited lectures IL1 ORIENTATION IN POLYMERS STUDIED BY VIBRATIONAL SPECTROSCOPY Christi... more s of the invited lectures IL1 ORIENTATION IN POLYMERS STUDIED BY VIBRATIONAL SPECTROSCOPY Christian Pellerin University of Montreal, Canada c.pellerin@umontreal.ca The properties and function of materials depend on their molecular structure and orientation. Our group develops and applies polarized infrared and Raman spectroscopy to gain insight into the structure of soft materials such as electrospun polymers, ultrathin films, molecular glasses and azomaterials. In this presentation, we will highlight our recent work on two classes of materials. Electrospun fibers show unusual properties that are poorly understood, such as an exponential increase of their modulus with a decreasing diameter. We used Raman spectroscopy at the single fiber level to show that this increase in modulus directly correlates with molecular orientation. We also probed the impact of the collection method on orientation development. Our results on polystyrene fibers further revealed a partial disentanglement th...
Bound and free water within dough strongly affect its rheological behavior and processability, as... more Bound and free water within dough strongly affect its rheological behavior and processability, as well as its gluten network. Depending on its total content and on the characteristics of flour constituents, water can be both bound to components and free in the dough. The equilibrium between bound and free water directly impacts the elasticity and extensibility of dough and therefore controls the texture of final products. In this study, Nuclear Magnetic Resonance (NMR) was used to assess the relaxation behavior with the focus on water. The proton spin-spin relaxation measurements were carried out at 20 MHz with a Bruker Minispec mq20 NMR spectrometer (Bruker, Rheinstetten, Germany). The transverse relaxation time in a spin locking field (T1?) was determined at 25°C following the Carr–Purcell–Meiboom–Gill (CPMG) sequence. The data were analyzed by the continuous distribution model. The dough was prepared with commercial semolina, which was mixed with water in a Brabender Mixer 350 (B...
Bound and free water within dough strongly affect its rheological behavior and processability, as... more Bound and free water within dough strongly affect its rheological behavior and processability, as well as its gluten network. Depending on its total content and on the characteristics of flour constituents, water can be both bound to components and free in the dough. The equilibrium between bound and free water directly impacts the elasticity and extensibility of dough and therefore controls the texture of final products. In this study, Nuclear Magnetic Resonance (NMR) was used to assess the relaxation behavior with the focus on water. The proton spin-spin relaxation measurements were carried out at 20 MHz with a Bruker Minispec mq20 NMR spectrometer (Bruker, Rheinstetten, Germany). The transverse relaxation time in a spin locking field (T1?) was determined at 25°C following the Carr–Purcell–Meiboom–Gill (CPMG) sequence. The data were analyzed by the continuous distribution model. The dough was prepared with commercial semolina, which was mixed with water in a Brabender Mixer 350 (B...
Paper Received: 25 August 2020; Revised: 17 February 2021; Accepted: 12 April 2021 Please cite th... more Paper Received: 25 August 2020; Revised: 17 February 2021; Accepted: 12 April 2021 Please cite this article as: Fanari F., Naue I.F., Desogus F., Grosso M., Wilhelm M., 2021, Durum Wheat Dough Torque Measurements: Characterization and Study of the Mixing Process Parameters as a Function of Water and Salt Amounts, Chemical Engineering Transactions, 87, 205-210 DOI:10.3303/CET2187035 CHEMICAL ENGINEERING TRANSACTIONS
A high sensitivity system for capillary rheometry capable of simultaneously detecting the onset a... more A high sensitivity system for capillary rheometry capable of simultaneously detecting the onset and propagation of instabilities and the first normal stress difference during polymer melt extrusion flows is here presented. The main goals of the study are to analyse the nonlinear dynamics of extrusion instabilities and to determine the first normal stress difference in the presence of an induced streamline curvature via the so-called ’hole effect’. An overview of the system, general analysis principles, preliminary results and overall framework are herein discussed.
This article presents a fast, straightforward synthesis approach to polymerize alternating multib... more This article presents a fast, straightforward synthesis approach to polymerize alternating multiblock copolymers, ultra‐high molecular weight (UHMW) (homo)polymers as well as precursors for complex macromolecular topologies such as comb or barbwire architectures. The one‐pot synthesis strategy proposed in this work is based on anionic polymerization via a bifunctional initiator and the subsequent linking of macro dianions with a bifunctional linker, additionally overcoming the limitations associated with the monomer reactivity. Thus, the synthetic route guarantees the repeating size of polymer blocks and an equal distribution of functional groups in precursors for complex topologies. Dianions of polystyrene (PS), polyisoprene‐b‐polystyrene‐b‐polyisoprene, and poly‐2‐vinylpyridine‐b‐polystyrene‐b‐poly‐2‐vinylpyridine are linked with ‐dibromo‐para‐xylene to UHMW and multiblock copolymers. Multiblock copolymers with on average up to 50 well‐defined alternating A and B blocks are access...
This paper presents the results of an interlaboratory study of the rheological properties of ceme... more This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the indivi...
Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic ... more Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (GIL′= 7.5 Pa at 100 rad s−1 and 298 K). Furthermore, the ionic conductivity (σ0) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10−4 S cm−1 at 298 K. Additionally, we found the Haven Ratio (HR) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room...
Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtain... more Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtained by commercial and monovarietal durum wheat flours (Cappelli and Karalis). Rheological frequency sweep tests were carried out, and the Weak Gel model, whose parameters may be related to gluten network extension and strength, was applied. IR analysis mainly focused on the Amide III band, revealing significant variations in the gluten network. Compared to the other varieties, Karalis semolina showed a higher amount of α-helices and a lower amount of β-sheets and random structures. Spectroscopic and rheological data were then correlated using Partial Least Squares regression (PLS) coupled with the Variable Importance in Projection (VIP) technique. The combined use of the techniques provided useful insights into the interplay among protein structures, gluten network features, and rheological properties. In detail, β-sheets and α-helices protein conformations were shown to significantly aff...
To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sam... more To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sample concentration profile is developed, which increases the sensitivity. The analytes can be characterized by evaluating the phase angle and magnitude.
Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic ... more Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (GIL′= 7.5 Pa at 100 rad s−1 and 298 K). Furthermore, the ionic conductivity (σ0) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10−4 S cm−1 at 298 K. Additionally, we found the Haven Ratio (HR) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room...
Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtain... more Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtained by commercial and monovarietal durum wheat flours (Cappelli and Karalis). Rheological frequency sweep tests were carried out, and the Weak Gel model, whose parameters may be related to gluten network extension and strength, was applied. IR analysis mainly focused on the Amide III band, revealing significant variations in the gluten network. Compared to the other varieties, Karalis semolina showed a higher amount of α-helices and a lower amount of β-sheets and random structures. Spectroscopic and rheological data were then correlated using Partial Least Squares regression (PLS) coupled with the Variable Importance in Projection (VIP) technique. The combined use of the techniques provided useful insights into the interplay among protein structures, gluten network features, and rheological properties. In detail, β-sheets and α-helices protein conformations were shown to significantly aff...
To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sam... more To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sample concentration profile is developed, which increases the sensitivity. The analytes can be characterized by evaluating the phase angle and magnitude.
s of the invited lectures IL1 ORIENTATION IN POLYMERS STUDIED BY VIBRATIONAL SPECTROSCOPY Christi... more s of the invited lectures IL1 ORIENTATION IN POLYMERS STUDIED BY VIBRATIONAL SPECTROSCOPY Christian Pellerin University of Montreal, Canada c.pellerin@umontreal.ca The properties and function of materials depend on their molecular structure and orientation. Our group develops and applies polarized infrared and Raman spectroscopy to gain insight into the structure of soft materials such as electrospun polymers, ultrathin films, molecular glasses and azomaterials. In this presentation, we will highlight our recent work on two classes of materials. Electrospun fibers show unusual properties that are poorly understood, such as an exponential increase of their modulus with a decreasing diameter. We used Raman spectroscopy at the single fiber level to show that this increase in modulus directly correlates with molecular orientation. We also probed the impact of the collection method on orientation development. Our results on polystyrene fibers further revealed a partial disentanglement th...
Bound and free water within dough strongly affect its rheological behavior and processability, as... more Bound and free water within dough strongly affect its rheological behavior and processability, as well as its gluten network. Depending on its total content and on the characteristics of flour constituents, water can be both bound to components and free in the dough. The equilibrium between bound and free water directly impacts the elasticity and extensibility of dough and therefore controls the texture of final products. In this study, Nuclear Magnetic Resonance (NMR) was used to assess the relaxation behavior with the focus on water. The proton spin-spin relaxation measurements were carried out at 20 MHz with a Bruker Minispec mq20 NMR spectrometer (Bruker, Rheinstetten, Germany). The transverse relaxation time in a spin locking field (T1?) was determined at 25°C following the Carr–Purcell–Meiboom–Gill (CPMG) sequence. The data were analyzed by the continuous distribution model. The dough was prepared with commercial semolina, which was mixed with water in a Brabender Mixer 350 (B...
Bound and free water within dough strongly affect its rheological behavior and processability, as... more Bound and free water within dough strongly affect its rheological behavior and processability, as well as its gluten network. Depending on its total content and on the characteristics of flour constituents, water can be both bound to components and free in the dough. The equilibrium between bound and free water directly impacts the elasticity and extensibility of dough and therefore controls the texture of final products. In this study, Nuclear Magnetic Resonance (NMR) was used to assess the relaxation behavior with the focus on water. The proton spin-spin relaxation measurements were carried out at 20 MHz with a Bruker Minispec mq20 NMR spectrometer (Bruker, Rheinstetten, Germany). The transverse relaxation time in a spin locking field (T1?) was determined at 25°C following the Carr–Purcell–Meiboom–Gill (CPMG) sequence. The data were analyzed by the continuous distribution model. The dough was prepared with commercial semolina, which was mixed with water in a Brabender Mixer 350 (B...
Paper Received: 25 August 2020; Revised: 17 February 2021; Accepted: 12 April 2021 Please cite th... more Paper Received: 25 August 2020; Revised: 17 February 2021; Accepted: 12 April 2021 Please cite this article as: Fanari F., Naue I.F., Desogus F., Grosso M., Wilhelm M., 2021, Durum Wheat Dough Torque Measurements: Characterization and Study of the Mixing Process Parameters as a Function of Water and Salt Amounts, Chemical Engineering Transactions, 87, 205-210 DOI:10.3303/CET2187035 CHEMICAL ENGINEERING TRANSACTIONS
A high sensitivity system for capillary rheometry capable of simultaneously detecting the onset a... more A high sensitivity system for capillary rheometry capable of simultaneously detecting the onset and propagation of instabilities and the first normal stress difference during polymer melt extrusion flows is here presented. The main goals of the study are to analyse the nonlinear dynamics of extrusion instabilities and to determine the first normal stress difference in the presence of an induced streamline curvature via the so-called ’hole effect’. An overview of the system, general analysis principles, preliminary results and overall framework are herein discussed.
This article presents a fast, straightforward synthesis approach to polymerize alternating multib... more This article presents a fast, straightforward synthesis approach to polymerize alternating multiblock copolymers, ultra‐high molecular weight (UHMW) (homo)polymers as well as precursors for complex macromolecular topologies such as comb or barbwire architectures. The one‐pot synthesis strategy proposed in this work is based on anionic polymerization via a bifunctional initiator and the subsequent linking of macro dianions with a bifunctional linker, additionally overcoming the limitations associated with the monomer reactivity. Thus, the synthetic route guarantees the repeating size of polymer blocks and an equal distribution of functional groups in precursors for complex topologies. Dianions of polystyrene (PS), polyisoprene‐b‐polystyrene‐b‐polyisoprene, and poly‐2‐vinylpyridine‐b‐polystyrene‐b‐poly‐2‐vinylpyridine are linked with ‐dibromo‐para‐xylene to UHMW and multiblock copolymers. Multiblock copolymers with on average up to 50 well‐defined alternating A and B blocks are access...
This paper presents the results of an interlaboratory study of the rheological properties of ceme... more This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the indivi...
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