Name: thermal scanning conductometry (tsc) as a general method for studying and controlling the phase behavior of conductive physical gels
Uploaded: 2018-01-23T13:30:00
Description: Watch this Scientific Journal Video about Thermal Scanning Conductometry TSC as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels at JoVE.com

Financial support for this work was provided by the National Center for Science as grant No. DEC-2013/11/D/ST3/02694.

1. Preparation of the Experimental Site for TSC Measurement
<ol>
	<li>To measure the full characteristics of the TSC method, use the commercially available conductometer equipped with four electrode cells (alternatively, two electrode cells can be used for low conductivities) and a temperature sensor. Connect it to the PC and record the conductivity and temperature of the sample (4% wt% of methyl-4,6-O-(p-nitrobenzylidene)-&#945;-D-glucopyranoside in 1 M molar concentration of tetraethylammonium bromide - TEABr in glyc...

<ol>
	<li>Bielejewski, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+approach+in+determination+of+ionic+conductivity+and+phase+transition+temperatures+in+gel+electrolytes+based+on+Low+Molecular+Weight+Gelators.">Novel approach in determination of ionic conductivity and phase transition temperatures in gel electrolytes based on Low Molecular Weight Gelators.</a> Electochim. Acta. 174, 1141-1148 (2015).</li><li>Bielejewski, M., &#321;api&#324;ski, A., Luboradzki, R., Tritt-Goc, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+solvent+on+the+thermal+stability+and+organization+of+self-assembling+fibrillar+networks+in+methyl-4,6-O-(p-nitrobenzylidene)-&#945;-D-glucopyranoside+gels.">Influence of solvent on the thermal stability and organization of self-assembling fibrillar networks in methyl-4,6-O-(p-nitrobenzylidene)-&#945;-D-glucopyranoside gels.</a> Tetrahedron. 67, 7222-7230 (2011).</li><li>Atsbeha, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photophysical+characterization+of+low-molecular+weight+organogels+for+energy+transfer+and+light+harvesting.">Photophysical characterization of low-molecular weight organogels for energy transfer and light harvesting.</a> J. Mol. Struct. 993, 459-463 (2011).</li><li>Gronwald, O., Snip, E., Shinkai, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gelator+for+organic+liquids+based+on+self-assembly:+a+new+facet+of+supramolecular+and+combinatorial+chemistry.">Gelator for organic liquids based on self-assembly: a new facet of supramolecular and combinatorial chemistry.</a> Curr. Opinion in Coll. Interface Sci. 7, 148-156 (2002).</li><li>Vintiloiu, A., Leroux, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organogels+and+their+use+in+drug+delivery-a+review.">Organogels and their use in drug delivery-a review.</a> Control. Rel. 125, 179-192 (2008).</li><li>Wang, Z., Fujisawa, S., Suzuki, M., Hanabusa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+Molecular+Weight+Gelators+Bearing+Electroactive+Groups+as+Cathode+Materials+for+Rechargeable+Batteries.">Low Molecular Weight Gelators Bearing Electroactive Groups as Cathode Materials for Rechargeable Batteries.</a> Macromol. Symp. 364, 38-46 (2016).</li><li>Sharma, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+gels+of+[BMIM][BF4]+by+N-tert-butylacrylamide/ethylene+oxide+based+triblock+copolymer+self-assembly:+Synthesis,+thermomechanical,+and+conducting+properties.">Physical gels of [BMIM][BF4] by N-tert-butylacrylamide/ethylene oxide based triblock copolymer self-assembly: Synthesis, thermomechanical, and conducting properties.</a> J. Appl. Polym. Sci. 128, 3982-3992 (2013).</li><li>Tao, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stable+quasi-solid-state+dye-sensitized+solar+cell+using+a+diamide+derivative+as+low+molecular+mass+organogelator.">Stable quasi-solid-state dye-sensitized solar cell using a diamide derivative as low molecular mass organogelator.</a> J. Power Sources. 262, 444-450 (2014).</li><li>Kataoka, T., Ishioka, Y., Mizuhata, M., Minami, H., Maruyama, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+Conductive+Ionic-Liquid+Gels+Prepared+with+Orthogonal+Double+Networks+of+a+Low-Molecular-Weight+Gelator+and+Cross-Linked+Polymer.">Highly Conductive Ionic-Liquid Gels Prepared with Orthogonal Double Networks of a Low-Molecular-Weight Gelator and Cross-Linked Polymer.</a> ACS Appl. Mater. Interfaces. 7, 23346-23352 (2015).</li><li>Bielejewski, M., Nowicka, K., Bielejewska, N., Tritt-Goc, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ionic+Conductivity+and+Thermal+Properties+of+a+Supramolecular+Ionogel+Made+from+a+Sugar-Based+Low+MolecularWeight+Gelator+and+a+Quaternary+Ammonium+Salt+Electrolyte+Solution.">Ionic Conductivity and Thermal Properties of a Supramolecular Ionogel Made from a Sugar-Based Low MolecularWeight Gelator and a Quaternary Ammonium Salt Electrolyte Solution.</a> J. Electrochem. Soc. 163, G187-G195 (2016).</li><li>Gronwald, O., Shinkai, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bifunctional'+sugar-integrated+gelators+for+organic+solvents+and+water-on+the+role+of+nitro-substituents+in+1-O-methyl-4,6-O-(nitrobenzylidene)-monosaccharides+for+the+improvement+of+gelation+ability.">Bifunctional' sugar-integrated gelators for organic solvents and water-on the role of nitro-substituents in 1-O-methyl-4,6-O-(nitrobenzylidene)-monosaccharides for the improvement of gelation ability.</a> J. Chem. Soc., Perkin Trans. 2, 1933-1937 (2001).</li><li>Bielejewski, M., Ghorbani, M., Zolfigol, M., Tritt-Goc, J., Noura, S., Narimani, M., Oftadeh, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermally+reversible+solidification+of+novel+ionic+liquid+[im]HSO4+by+self-nucleated+rapid+crystallization:+investigations+of+ionic+conductivity,+thermal+properties,+and+catalytic+activity.">Thermally reversible solidification of novel ionic liquid [im]HSO4 by self-nucleated rapid crystallization: investigations of ionic conductivity, thermal properties, and catalytic activity.</a> RSC Adv. 6, 108896-108907 (2016).</li></ol>

The thermal scanning conductometry is a new experimental method which has proven to be an efficient and effective way of investigating dynamically changing systems, like ionogels based on low molecular weight gelators, electrolytes, or ionic liquids. However, its applicability is not restricted only to ionogels. The TSC method can be easily used with other types of conducting soft matter systems like hydrogels, emulsions, creams, or any other charge containing carriers into which the conductivity sensor can be inserted. ...

Thermally Reversible Ionogels 
Physical gelation is a process which allows the construction of structures of self-assembled gelator molecules in presence of the solvent molecules. Due to non-covalent nature of the interactions responsible for this phenomenon (e.g. hydrogen bonding, van der Waals interactions, dispersion forces, electrostatic forces, &#960;-&#960; stacking, etc.), these systems are thermally reversible. This thermal reversibility, together with the very low concentration of the gelator and the wide variety of the systems that can be created, are some of the main advantages of physical gels over chemical ones. Thanks to the unique properties of the physical gel state, the ionogels are characterized with desirable features like easy recycling, long cycle life, enhanced physical properties (e.g. ionic conductivity), ease of production, and lowering of the production costs. Taking into the account the above advantages of physical gels (which already have a wide range of different applications1,2,3,4), these were thought to be used as an alternative way for electrolyte solidification and obtaining of ionogels5,6,7,8. However, the classical conductometry was not sensitive and accurate enough to follow such dynamically changing systems. Therefore,it could not detect the phase transitions and enhanced dynamics of ions in the gel matrix9. The reason for this insensitivity was the time needed for the temperature stabilization, during which dynamic changes of the sample properties were underway before the measurement was started. Furthermore, the number of measured temperatures was limited in order, not to significantly extend the experimental time. Therefore, to fully and accurately characterize the ionogels, a new method was needed, which would be able to follow the dynamic changes of properties as a function of temperature, and record data continuously in real time. The way the gelation process is conducted determines the properties of the created ionogel. The intermolecular non-covalent interactions are defined during the cooling stage; by changing the gelation temperature and cooling rates, one can strongly influence those interactions. Therefore, it was extremely important to measure the system during cooling when the gelation takes place. With the classical approach, this was impossible due to temperature stabilization time for the measurement, and the fast cooling rates required for successful gelation. However, with the thermal scanning conductometry method this task is very simple, delivers accurate and reproducible results, and allows the investigation of the influence of different kinetics of thermal changes applied to the sample on sample properties10. As a result, the ionogels with targeted properties can be studied and manufactured at the same time.
Thermal Scanning Conductometry (TSC) 
The thermal scanning conductometry is supposed to deliver a reproducible, accurate, and fast responding experimental method for the conductivity measurement of dynamically changing and thermally reversible systems, like ionogels based on low molecular weight gelators. However, it can be also used with electrolytes, ionic liquids, and any other conducting sample that can be placed in the measuring cell and has conductivity in the measuring range of the sensor. Additionally, besides the research application, the method was successfully used to manufacture ionogels with targeted properties like microstructure, optical appearance or thermal stability, and phase transition temperature in an accurate and easy way. Depending on the kinetics and history of thermal treating with use of the TSC method, we gain full control over some basic properties of physical gel systems. Additionally the chamber have been equipped in a video camera to inspect the sample state and record the changes of the sample especially during gelation and dissolution processes. An additional advantage of the TSC method is its simplicity, as the system can be built from a standard conductometer, a programmable temperature controller, the gaseous nitrogen line for the heating/cooling medium, the refrigerator, measuring chamber, and a PC, which can be found in most laboratories.
The TSC Experimental Site 
The thermal scanning conductometry experimental setup can be built in almost every laboratory with relatively low costs. In return, one obtains an accurate, reproducible, and fast method for measuring liquid and semisolid conductive samples at different external conditions. A detailed scheme of the TSC experimental setup built in our laboratory is given in Figure 1.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56607/56607fig1v2.jpg" /> 
Figure 1: Block diagram of the measurement site. The components consisting on working experimental setup for thermal scanning conductometry method. <a href="//cloudflare.jove.com/files/ftp_upload/56607/56607fig1v2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
For the temperature change, a homemade temperature controller was used, but any kind of programmable temperature controller, which can change the temperature linearly with a defined change rate, can be used. For thermal isolation, a special chamber has been built. The purpose of using an isolation chamber is to minimize temperature horizontal gradients in the sample, and to assure fast cooling rates. The chamber consists of a glass cylinder with a 40-mm inner diameter and 300 mm length. At the bottom side, where the heater with gaseous nitrogen inlets are located, the end of the inlet is equipped with a diffusor to evenly spread the hot or cold gas. This is also the place where the temperature sensor PT100 of the variable temperature controller (VTC) is located. The temperature of the sample is recorded independently by the temperature sensor located in the conductivity sensor. Additionally, the chamber have been equipped in a video camera to inspect the sample state and record the changes of the sample especially during gelation and dissolution processes. The gaseous nitrogen obtained from evaporation of liquid nitrogen in the 250 L high pressure tank is used as a heating and cooling medium. The working pressure in the nitrogen line is set to 6 bars, and reduced to 2 bars at the measuring site. Such settings allow the obtainment of flow rates between 4 and 28 L/min without any disturbances, which allows a cooling rate of 10 &#176;C/min. To lower the initial temperature of the nitrogen gas, the external refrigerator has been used, and the decreased temperature was 10 &#176;C. This allows the obtainment of good linearity of the temperature change, starting from room temperature. During fast cooling, the temperature of the nitrogen gas is decreased to -15 &#176;C to assist high cooling rates. It is necessary to use gaseous nitrogen, and not even dry air, to avoid icing the refrigerator because of low temperatures.
The samples were inserted into a vial of 9 mm inner diameter and length of 58 mm, made of polypropylene, and equipped with a screw cap, which has a rubber ring for tight closing. The vials can be used up to 120 &#176;C. (see Figure 2).
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56607/56607fig2.jpg" /> 
Figure 2: The picture of a polypropylene vial and its mounting on the conductivity sensor. (1) the polypropylene vial, (2) the screw cap with rubber ring, 2a - the screw cap mounted on the conductivity sensor, (3) the vial with mounted conductivity sensor, the screw cap secured with Teflon tape. <a href="//cloudflare.jove.com/files/ftp_upload/56607/56607fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

<table border="0" cellpadding="0" cellspacing="0" width="698">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">SevenCompact S230 conductometer</td>
			<td style="width:140px;">Mettler-Toledo</td>
			<td style="width:119px;"></td>
			<td style="width:223px;">equiped with InLab 710 sensor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">home-build VTC</td>
			<td style="width:140px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:216px;">LabX PH 3.2 software</td>
			<td style="width:140px;">Mettler-Toledo</td>
			<td style="width:119px;"></td>
			<td>software used for data aqusition</td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:216px;">tetraethylammonium bromide</td>
			<td style="width:140px;">Sigma-Aldrich</td>
			<td style="width:119px;">140023</td>
			<td></td>
		</tr>
		<tr height="30">
			<td height="30" style="height:30px;width:216px;">glycerol</td>
			<td style="width:140px;">Sigma-Aldrich</td>
			<td style="width:119px;">G5516</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">methyl-4,6-O-(p-nitrobenzylidene)-a-D-glucopyranose</td>
			<td style="width:140px;"></td>
			<td style="width:119px;"></td>
			<td style="width:223px;">synthezied according to Gronwald, O., Shinkai, S., J. chem. Soc., Perkin Trans. 2 1933-1937 (2001).</td>
		</tr>
		<tr height="201">
			<td height="201" style="height:201px;width:216px;">[im]HSO4</td>
			<td style="width:140px;"></td>
			<td style="width:119px;"></td>
			<td style="width:223px;">synthezeid by group of prof. Mohammad Ali Zolfigol, Faculty of Chemistry 
			Bu-Ali Sina University 
			Hamedan, I.R.Iran&#160; according to Bielejewski, M., Ghorbani, M., Zolfigol, M., Tritt-Goc, J., Noura, S., Narimani, M., Oftadeh, M. RSC Adv. 6, 108896-108907 (2016).</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">polypropylene vial</td>
			<td style="width:140px;">Paradox Company, Cracow, Poland</td>
			<td style="width:119px;">PTC 088</td>
			<td>www.insectnet.eu</td>
		</tr>
	</tbody>
</table>

thermal scanning conductometry (tsc) as a general method for studying and controlling the phase behavior of conductive physical gels

The thermal scanning conductometry protocol is a new approach in studying ionic gels based on low molecular weight gelators. The method is designed to follow the dynamically changing state of the ionogels, and to deliver more information and details about the subtle change of conductive properties with an increase or decrease in the temperature. Moreover, the method allows the performance of long term (i.e. days, weeks) measurements at a constant temperature to investigate the stability and durability of the system and the aging effects. The main advantage of the TSC method over classical conductometry is the ability to perform measurements during the gelation process, which was impossible with the classical method due to temperature stabilization, which usually takes a long time before the individual measurement. It is a well-known fact that to obtain the physical gel phase, the cooling stage must be fast; moreover, depending on the cooling rate, different microstructures can be achieved. The TSC method can be performed with any cooling/heating rate that can be assured by the external temperature system. In our case, we can achieve linear temperature change rates between 0.1 and approximately 10 &#176;C/min. The thermal scanning conductometry is designed to work in cycles, continuously changing between heating and cooling stages. Such an approach allows study of the reproducibility of the thermally reversible gel-sol phase transition. Moreover, it allows the performance of different experimental protocols on the same sample, which can be refreshed to initial state (if necessary) without removal from the measuring cell. Therefore, the measurements can be performed faster, in a more efficient way, and with much higher reproducibility and accuracy. Additionally, the TSC method can be also used as a tool to manufacture the ionogels with targeted properties, like microstructure, with an instant characterization of conductive properties.

The organic ionic gels constitute a new class of functional materials which can become an alternative solution for polymer gel electrolytes. However, to achieve this aim, these gels have to be deeply investigated and understood. The thermally reversible character of the gelation process, and the dynamically changing properties of temperature and phase occurrence, required a new experimental method which will allow the recording of data and detection of subtle changes in temperature change...

Watch this Scientific Journal Video about Thermal Scanning Conductometry TSC as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels at JoVE.com

Thermal Scanning Conductometry TSC as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels

The kinetics of the cooling process defines the properties of ionic gels based on low molecular weight gelators. This manuscript describes the usage of thermal scanning conductometry (TSC), which obtains full control over the gelation process, along with in situ measurements of the samples' temperature and conductivity.

Thermal Scanning Conductometry (TSC) as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels

The thermal scanning conductometry protocol is a new approach in studying ionic gels based on low molecular weight gelators. The method is designed to ...

The overall goal of this experiment is to develop a reliable and easy method to investigate the dynamically changing state of ionogels and to obtain information about subtle changes of their conductive properties during heating and cooling. This method can help answer key questions in the ionogels field, such as how the dynamics and conductive properties change when transitioning between the liquid and gel states. The main advantage of this technique is that it can follow subtle changes of the conductive and thermal properties of a sample during the gelation process and distinguish between the phases.Most laboratories have the equipment for a thermal scanning conductometry set up. At its core is the measurement chamber. Nitrogen gas flows into a gas dewar with a heater.The nitrogen passes through a gas mixer that is just below a sample in a polypropylene tube. The tube is attached to a conductometry sensor that is immersed in the sample. For an experiment, set up the apparatus under a fume hood.Surround the sample and sensor with thermal insulation. A sense of the complete setup is provided by this schematic. A liquid nitrogen tank provides gaseous nitrogen for a heating and cooling medium.The nitrogen passes through a sample cooler, and its temperature is regulated by a variable temperature controller. In the experimental chamber, the conductometer measures the conductivity and the temperature in the middle of the sample. A computer records the conductivity, temperature and time for each measurement.At this point, prepare the experiment sample. To hold the sample, use a polypropylene vial with a screw cap and a rubber ring for tight closing. Begin with a cap then drill a hole to accommodate the conductive sensor, as with this example.Next, take the cap to the sensor where it will be mounted. Orient the cap so that the vial can be screwed onto it before sliding the cap along the sensor. Position the cap so that the sensor will be approximately at the center of the vial.Once in place, secure the cap with Teflon tape. Ensure the cap is tightly mounted and secured before continuing. Preparing the electrolyte requires some equipment.There should be a scale, a heating block at 100 degrees Celsius and a mixer. Obtain the solvent and solute for the electrolyte solution. Employ the scale to weigh the required amount of compounds for the desired concentration, here, a one-molar solution.Mix the two compounds in a glass vial that can be tightly closed. After mixing, close the vial and heat it at 100 degrees Celsius for 15 minutes. Then remove the vial from the block and place it on the mixer for one minute.Heat the vial again at 100 degrees Celsius for five minutes to ensure the mixture is homogenous. When done, the electrolyte can be stored at room temperature. Preparation of the gels requires the previously made electrolyte solution.It also requires low-molecular-weight gelator. For equipment, be ready to heat the sample at 130 degrees Celsius. Also, have a dry cooling block at 10 degrees Celsius.Begin with four millimeters of the electrolyte in a glass vial. Add 178.6 milligrams of the gelator to create a 4%by weight ionic gel sample. Heat the vial at 138 degrees Celsius for 20 minutes.During the 20 minutes, occasionally stir the contents of the vial to assist dissolution of the gelator in the electrolyte then continue with heating the sample until it is homogenous. When the sample is homogenous, quickly move the vial to the dry cooling block. After cooling, the result will be physical gelation to a homogenous gel phase.For the measurement, set the nitrogen pressure to two bars and the flow to 10 liters per minute. Check that the data acquisition system will record the conductivity, temperature and time of each measurement. Next, move to the bench to work with the sample.Have a polypropylene vial pre-cooled to 10 degrees Celsius. Take a gel sample and place it on the heater block. Raise the sample temperature above the gel-sol transition temperature.Once the gel is in the sol phase, retrieve its container and transfer the gel to the pre-cooled vial. The fast cooling of the sol will produce the gel phase. Next, get the conductivity sensor with the vial cap.Push the sensor into the vial and gel so that the vial can be screwed into the cap. Mount the sensor and sample in the thermal scanning conductometry set-up using a viewport to check for correct positioning. First, do a heating-cooling cycle without performing measurements.This video tracks the changes of a sample as it rises from its gelation temperature of 10 degrees Celsius with a heating rate of two degrees Celsius per minute. The sample reaches the sol phase and then a temperature of about 100 degrees Celsius before it is cooled at a rate of seven degrees Celsius per minute back to 10 degrees Celsius. As it cools, gelation begins, and the sample ends in the transparent ionogel phase.This cycle improves electrode contact and removes imperfections. Hold the sample at 10 degrees Celsius while setting up the conductometer to perform measurements. When ready, perform measurements using the same cycle parameters.The sample temperature as a function of time is displayed here as it rises from its gelation temperature of 10 degrees Celsius to 100 degrees Celsius and back. Also plotted are the evolution of the conductivity as a function of temperature and as a function of time over the course of the cycle. The inset video tracks the sample changes.This is an example of the final transparent gel phase of the sample. For the next heating-cooling cycles, start at 10 degrees Celsius and set both the heating and cooling rate to two degrees Celsius per minute. This experiment records begins as the sample cools from the sol phase at a temperature of about 100 degrees Celsius to its gelation temperature of 10 degrees Celsius.As the sample reaches the gelation temperature, it is in a mixture of the transparent and opaque gel phase. The final transparent and opaque gel mixed phase is clearly seen here. For the final heating-cooling cycles, start the sample at 10 degrees Celsius, maintain the heating and cooling rates at two degrees Celsius per minute and use a gelation temperature of 60 degrees Celsius.As the sample cools from the sol phase at about 100 degrees Celsius, stop the cooling when it reaches the gelation temperature of 60 degrees Celsius. Maintain the gelation temperature for 20 minutes. For this cycle, the final result is an opaque, white gel phase.To perform another cycle, first reduce the temperature to 10 degrees Celsius and hold for 20 minutes. These data are for a heating rate of two degrees Celsius, cooling rate of seven degrees Celsius and gelation temperature of 10 degrees Celsius. The heating curve is in red.The cooling curve is in blue. Identify the phase transition from transparent gel to sol phase by analyzing the first derivative. Similar analysis for this sample, with a mixed transparent and opaque gel phase, identifies two phase transitions, one for each phase.These data are for a heating and cooling rate of two degrees Celsius and a gelation temperature of 10 degrees Celsius. A sample with just an opaque gel phase has one phase transition. In this case, the heating and cooling rates were both two degrees Celsius, and the gelation temperature was 60 degrees Celsius.This technique paves the way for the researchers studying the ionogels as alternatives for electrolyte solidification to explore thermal and conductive properties of systems, which is crucial for future applications. Once mastered, this technique can deliver not only reliable and reproducible results in an easy and straightforward way but can be used to manufacture ionogels with targeted properties with easy-to-do characterization. After watching this video, you should have a good understanding of how to build your own experimental site for the thermal scanning conductometry method and how to perform the measurements.

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