Ionic Polymer Transducers Research Articles

Electronic-ionic polymer composite for high output voltage generation

The ionic polymer transducers (IPT) have been widely proposed for actuators, energy harvesting, pressure sensing, and robotics applications owing to their exceptional flexibility and actuation performance. However, IPT sensors have a limitation of low output voltage (<1 V) with bending strain that hampers their application in energy harvesting devices and robotics. To address the issue of low output voltage in IPT sensors, we propose a strategy including the introduction of poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) into a poly(vinylidene-fluoride-trifluoroethylene-chlorotrifluoroethylene) (P(VDF-TRFE-CTFE)/polyvinylpyrrolidone blend to develop the electronic-ionic polymer composite (EIPC) that exhibits a high output voltage of up to 27 V in ionic liquid (IL) condition. The PVP aids in the formation of 89 nm (nm) PEDOT:PSS crystals, a low contact angle of 53.75°, and pores on the surface of the P(VDF-TRFE-CTFE)/PVP/PEDOT:PSS-based EIPC with a ratio of 10/05/85, resulting in high water uptake (WUP) (0.92), high DC conductivity (σdc) (0.02 S/cm) and high electrical current 0.02 A/cm2, which improve the high output voltage (27 V) and output power density (4.05 W/cm2) compared to previous existing PEDOT based composites sensors and IPTs based on P(VDF-TRFE-CTFE)/PVP/ionic liquid, P(VDF-TRFE-CTFE)/PVP/PSSA and Nafion membranes. For wearable sensor application, the EIPC was attached to the index finger of humans and generated 25 V with bending of the finger with an angle of 180°. With high ductile nature (tensile strain 223%) and high output voltage of 27 V with bending strain, the EIPC sensors will find practical applications in strain sensors, wearable devices, and energy harvesting devices.

Development of ionic liquid-based electroactive polymer composites using nanotechnology

Abstract This review is intended to provide an overview of the design and fabrication of ionic liquid-based ionic electroactive polymer (IL-iEAP) transducers for advanced applications in biological and electronic fields. The iEAP is a class of smart materials that can perform sensing or actuating functions by controlling the movement of cations and anions in the active layer. This type of material can deform under low voltage stimulation and generate electrical signals when undergoing mechanical deformation because of ion redistribution. Numerous research attention has been focused on studying the deformation mechanisms and the potential for actuation, sensing, and energy harvesting applications. Compared to the traditional water-based iEAP, the non-volatile IL-iEAP delivers a wider electrochemical window and a more stable actuation performance. In this paper, the classification of iEAP with different actuation mechanisms is first outlined, followed by introducing various preparation methods including nanotechnology for IL-iEAPs, and discussing the key factors governing their actuation performance. In addition, the advanced functions of IL-iEAP in actuating and sensing, especially self-sensing in bionics and electromechanical equipment applications, are reviewed. Finally, novel nanotechnologies used for fabricating IL-iEAPs and the prospects of their microelectromechanical system (MEMS) applications are discussed.

Modeling, fabrication, and characterization of motion platform actuated by carbon polymer soft actuator

Carbon polymer composites (CPC) are kind of soft actuators belonging to the category of ionic electroactive polymer transducers. In this work, we present design, modeling, fabrication, and characterization of a novel parallel manipulation system actuated by the CPC actuators. In this system, four actuators are operated in parallel to manipulate an end effector or a platform to generate motion along the different axis. The major advantage of the current system is that the platform and the actuators are fabricated as a single structure using the simple layer-by-layer spray-deposition method with selective masking. The proposed system is highly dexterous and is capable of generating three degrees of motions, namely, roll, pitch, and piston. The initial structural design and its deformation are optimized by modeling and simulating using finite element method and followed by fabrication and characterization to examine its workspace. The experimental results have demonstrated high levels of manipulability from the CPC actuators that are outstanding in the class of soft ionic actuators while keeping the fabrication method simple, scalable and cost-effective. The proposed configuration has potential application in micromanipulation systems that require large deformation in a confined space.

Experimental and theoretical investigation of ionic polymer transducers in shear sensing

Ionic polymer transducers (IPTs), sometimes referred to as ionic polymer metal composites, are ionomers that are plated with conductive media such as metals enabling both actuation and sensing behavior. As sensors they are most often studied in bending mode; however, a measurable signal can be generated in any mode of mechanical deformation. The fundamental physical mechanism responsible for IPT sensing is an open topic. This report asserts that a reasonable mechanistic model should be able to explain IPT sensing in any mode of deformation; the specific hypothesis offered here is the streaming potential hypothesis. In this paper, mathematical modeling of IPTs in shear sensing is presented in comparison with experiments. The experimental studies introduce a novel shear test apparatus for step-loading shear deflection and in situ measurement of resulting transient IPT current. The modeling estimations and experimental outcomes show good agreement, in terms of current output variation for imposed shear deformation magnitude, moreover, in the optimum metal particulate loading in the electrode layers leading to maximum shear sensitivity. The optimum metal concentration was determined to be in the vicinity of 40% for metal particulates by volume demonstrating the influence of electrode structure on the sensing response.

Multi-scale modeling of ion transport in high-strain ionomers with conducting powder electrodes

Ionomeric polymer transducers exhibit electromechanical coupling capabilities. The ion transport due to electric stimulus is the primary mechanism of actuation for a class of polymeric active materials known as ionomeric polymer transducers. In this article, a two-dimensional Monte Carlo simulation of ion hopping has been developed to describe ion transport in materials that have fixed and mobile charge similar to the structure of the ionic polymer transducer. Such Monte Carlo simulations were performed to study the influence of conducting powder electrodes on stationary ion distribution in actuation. Ion accumulation around the powder sphere at the cathode is clearly observed in simulation results. Moreover, based on the unique property of stationary charge density of ionomeric polymer transducers in actuation, this article proposed a novel multi-scale model connecting Monte Carlo simulation for the material boundaries and a continuum model for the central part. To validate this multi-scale model, the simulation results are compared with experimental measurements. Both transient and steady-state responses from the experiments show reasonable agreement with those from the multi-scale model.

Experimental investigation of the streaming potential hypothesis for ionic polymer transducers in sensing

Ionic polymer transducers (IPTs) are ionomers that are plated with conductive media such as metals, leading to capacitive behavior. IPTs exhibit bending deformation when a voltage difference is applied across the surfaces of the transducer, thus displaying actuation. A current is generated when they are deformed, thus exhibiting sensing. However, the mechanisms responsible for actuation and sensing differ; research to date has focused predominantly on actuation, while identification of the dominant mechanism responsible for IPT sensing remains an open topic. The goal of this work is to initiate experimental investigations of the streaming potential hypothesis for IPT sensing. This hypothesis argues that the presence of unbound counter-ions within the hydrophilic phase of an ionic polymer behaves as an electrolyte in the presence of the electrode. Thus, as per classic streaming potential analyses, relative motion of the electrolyte with respect to the electrode will result in the evolution of a streaming potential. According to this hypothesis, the extent of communication between the electrode and electrolyte becomes important in the evolution of an electrical signal. This study experimentally explores the effect of electrode architecture on the sensing response where the IPTs are prepared via the direct assembly process (DAP). The DAP is selected because it enables control over the fabrication of the electrode structure. In this study, cantilevered IPT samples having different electrode composition are tested under several step input tip displacements. The experimental outcomes are consistent with predicted trends via streaming potential theory.

Softening and heating effects in ionic polymer transducers: An experimental investigation

This study reports the softening and heating of ionic polymer transducers during actuation. This is the first account of such effects that will impact the understanding of the actuation mechanisms and the physical modeling of these actuators. The ionic polymer transducer samples are characterized in the extensional mode under a variety of mechanical boundary conditions, as a function of the electrode architecture and the cation species. For instance, the electrode thickness is varied from 10 to 40 µm while three extensional actuators with lithium, cesium, and tetraethylammonium mobile cations are characterized. The actuators are characterized under the following boundary conditions: free displacement, spring loaded with a varied amount of prestress, and constant applied pressure. The softening behavior is observed when the prestressed actuator contracts rather than expands as expected in the extensional mode. While the heating effect is observed when transducers characterized with a high-frequency alternating current, excitation generated a logarithmic like response similar to that of a step input. The shape of this response is correlated with the measured temperature of the actuator. However, when actuated with a low-frequency (&lt;0.1 Hz) alternating current signal, the ionic polymer transducer responded with a sine displacement containing a strong first harmonic. Furthermore, experimental results demonstrate a strong correlation between electrode architecture and the peak strain response. Extensional strains on the order of 1.35% are observed with air stable ionic liquid-based transducers. Ionic polymer transducers with cesium (Cs) cation outperformed all other tested actuators with other mobile species.

Design of an improved signal conditioning circuit for ionic polymer sensors based on the streaming potential hypothesis

Ionic polymer transducers also known as ionic polymer metal composites belong to the family of electroactive polymer transducers. Electroactive polymers are flexible and lightweight devices that operate as sensors and actuators without having any internally moving parts. The absence of moving parts offers a more efficient and cost-effective transducer with increased reliability. As actuators, ionic polymer transducers have the ability to generate bending strains on the order of 5% when +2 V potential is applied across their thickness. However, as sensors, the ionic polymer transducer has superior sensitivity as compared to other electroactive polymer materials. This is especially true when a charge or current amplifier is used as the signal conditioning circuit. These sensors operate in a wide spectrum and specifically at small strains. In this article, a new signal conditioning circuit is designed with superior sensing capabilities compared to the conventional circuit. In the new design, the ionic polymer transducer is biased with a small voltage on the order of 5 to 25 mV. Experimental results demonstrate a 27% enhancement in the current generated and the signal-to-noise ratio as compared to the conventional circuit. Furthermore, this circuit enables the use of ionic polymer transducer polymers with larger capacitance compared to the previous current sensing circuit. Earlier research demonstrates that the capacitance of an ionic polymer transducer is proportional to its actuation performance, and it is believed to affect the sensing performance. To increase the capacitance, the direct assembly process is used in the fabrication of ionic polymer transducer. Previously, using the conventional current amplifiers, it was impossible to use a direct assembly process–fabricated ionic polymer transducer with a large capacitance as a sensor, since it would saturate the operational amplifier circuit. In this study, three types of operational amplifier circuits are investigated, and their ability to bring the sensor to a short-circuit condition is measured. The signal-to-noise ratio of the operational amplifiers is measured and the OP177 has proved to be the best in both experiments.

Experimental demonstration of the active area model in extensional ionic polymer transducers

Ionic polymer transducers (IPTs) also known as ionic polymer metal composites (IPMCs) are soft smart materials that are well characterized in bending actuation. A salient feature of an IPT is its ability to generate large strains of the order of 5% at moderate voltages ( < 2 V). The authors previously reported extensional actuation in IPTs, which in theory is supposed to generate larger energy densities as compared to bending actuation. The experiments in the previous study were limited to the measurement of an AC force response in IPTs. This paper presents DC and AC experimental measurements of the free displacement in extensional IPT actuators. The active area model presented in the previous study is employed in this study and is proven to accurately predict the displacement behavior. Moreover, the magnitudes of the α and β coupling coefficients in the active area model required to fit the displacement data are within the ranges reported in the previous study. Furthermore, the active area model is based on the assumption that the high surface area electrodes are the only active components, while the inner ionomer membrane acts as an ion transport medium and does not perform any electromechanical coupling. This assumption is proved in this study by replacing the central Nafion membrane with a passive AlO2 porous film filled with the EMI-TF ionic liquid. The actuator with the AlO2 membrane demonstrates electromechanical extensional response faster than that in the Nafion based transducer. The large stiffness of the AlO2 based transducer is expected to provide larger forces and results in an actuator with greater energy density.

Liquid crystal polymers and ionomers for membrane applications

Transport phenomena through polymeric composite membranes depend on several complex factors, involving not only their chemical composition but also their microstructure. Due to the combination of mesomorphic and macromolecular behaviour, thermotropic liquid crystal polymers (LCP) may enhance the transport properties in membranes by improving parameters related to the order, orientation, connectivity and distribution of the different domains arising from phase separation. This paper provides an overview of some existing and potential applications of liquid crystals (LC) in polymeric membranes as effective structure-directing templates or as components providing a dynamic response to external stimuli. The first part is a description of the composition and phase behaviour of LCP containing ionic and ionogenic groups, the so-called liquid crystal ionomers (LCI). The second part is focused on the description of LCP and LCI used in transport applications, such as proton-conducting films in fuel cells, ionic polymer transducers and hydrogels. The paper highlights the relationships between the composition and the LC properties of the materials and their potential as membranes for ionic and solvent transport, with particular attention paid to covalently linked materials prepared by copolymerisation, due to their higher versatility and stability.

Prediction of the ionic polymer transducer sensing of shear loading

While ionic polymer transducers (IPTs) have often been studied as actuators, they alsoshow considerable promise as sensors. In addition to responding to bending, IPT sensorscan also detect compression, tension and shear. Existing IPT models focus primarily onactuation, while the few available sensing models are limited to bending. This is due in partto the lack of a viable hypothesis for a physical mechanism that can explain the existenceof a sensing signal in all deformation modes. Identification of the fundamental sensingmechanism is desirable as it could ultimately be exploited to design IPT sensors with anoptimized response. Here it is hypothesized that the dominant physical mechanism forsensing is streaming potential, as it holds promise for explaining the existence ofIPT sensing in any mode of deformation. We present a model for predicting thecurrent developed when an IPT is subject to shear deformation, the creation ofwhich has previously been elusive. The presented study employs a finite elementapproach to predict diluent flow with respect to the surrounding hydrophobicamorphous region under shear loading. Assessment of multiple flow path orientationswith respect to load is used to impose volume averaging, and subsequently toproject transducer current. Both peak and transient response are considered.Model predictions compare well with previously reported experimental results.

Streaming Potential Hypothesis for Ionic Polymer Transducers in Sensing: Roles of Ionomer State and Morphology

To date, consensus has not been reached on the underlying physical mechanism responsible for the experimentally observed sensing response of ionic polymer transducers, sometimes referred to as ionic polymer-metal composites. It is understood that a robust hypothesis will be able to accommodate a range of experimental observations. Moreover, because the actual morphology of ionic polymers is (a) an open topic and (b) expected to vary, a robust sensing hypothesis should additionally be decoupled from any particular morphological assumption. Explored here is the streaming potential hypothesis. As per this hypothesis, the magnitude of the predicted electromechanical response will vary with assumed morphology, but will always exist. This study demonstrates scenarios including predicting the evolution of sensing with diluent and cation variations for two morphological propositions. Specifically, sensing predictions are offered for a Nafion-based sensor (a) exchanged with lithium versus sodium cations, (b) imbued with water versus ionic liquid diluents, and (c) each of these cases is considered for a parallel circular cylindrical channel morphology versus a spherical cluster morphology. Both candidate morphologies correctly predict higher sensitivity for the lithium exchanged and water imbued cases.

THE INFLUENCE OF MICROSTRUCTURE ON BOUNDARY LAYER INTERACTIONS IN IONIC POLYMER TRANSDUCERS

Ionic polymer transducers (IPTs), also known as ionic polymer-metal composites (IPMCs), are smart sensors and actuators which operate through a coupling of micro-scale chemical, mechanical, and electrical interactions. It is known that ion movement, when a voltage is applied, causes stresses which lead to a net bending movement of a cantilevered transducer towards the anode. However, it is not well understood how these stresses arise, and it is not known how the material microstructure affects the observed macroscopic bending response. In this work, we apply a micromechanics modeling framework to analyze how assumptions of the material microstructure of an IPT affect local interactions and the resulting boundary layer stresses which lead to actuation. In the micromechanics framework, local equilibrium consists of a balance between internal cluster pressure and the stress developed in the polymer backbone. Here, we derive a generalized expression for the electrostatic cluster pressure and show how it depends on microstructure and microstructural evolution in the boundary layers. It is proposed that the boundary layer stiffness varies locally with changes in solvent uptake and charge density; this relationship is defined from micromechanics equilibrium conditions and includes effects of the generalized electrostatic cluster pressure. By assuming a relationship between ion and solvent movement, we then examine how boundary layer stresses are affected by assumptions of the material microstructure. The results and implications of the model are compared with recent experimental observations as well as other models of IPT actuation.

Nonlinear capacitance and electrochemical response of ionic liquid-ionic polymers

In this paper we present a physics-based model for the electrochemical response of ionic liquid-ionic polymer transducers (IPTs) and show how the mobile ionic liquid ions influence the charging characteristics and actuation performance of a device. It is assumed that a certain fraction of the ionic liquid ions exist as “free,” making for a total of 3 mobile ions. This leads to predictions of distinctly different charging characteristics for ionic liquid versus water-based IPTs, since for the latter there is only a single mobile ion. The large ionic liquid ions are modeled by including steric effects in a set of modified Nernst-Planck/Poisson equations, and the resulting system of equations is solved using the method of matched asymptotic expansions (MAE). The inclusion of steric effects allows for a realistic description of boundary layer composition near actuator operating voltages (~1 V). Analytical expressions for the charge transferred and differential capacitance are derived as a function of the fraction of free ionic liquid ions, influence of steric effects in formation of the electric double layer, and applied voltage. It is shown that the presence of free ionic liquid ions tends to increase the overall amount of charge transferred, and also leads to a nonmonotonic capacitance-voltage curve. We suggest that these results could be used to experimentally identify the extent of free ionic liquid ion movement and to test the validity of the assumptions made in the underlying theory. A comparison with numerical results shows that while the MAE solution procedure gives valid results for capacitance and charge transferred, it cannot predict the dynamic response due to the presence of multiple time scales in the current decay. This is in contrast to previous results in analyzing water-based IPTs, where the MAE solution is in good agreement with numerical results at all times and applied voltages due to the presence of only a single mobile ion. By examining the structure of the electric double layer in the ionic liquid IPT, it is shown that although the additional mobile ions lead to more charge transferred, they likely do not increase the bending moment generated by a cantilevered IPT because of the increase in symmetry in boundary layer charge density profiles. These results are in good qualitative agreement with recent experiments.

High surface area electrodes in ionic polymer transducers: Numerical and experimental investigations of the electro-chemical behavior

Ionomeric polymer transducer (IPT) is an electroactive polymer that has received considerable attention due to its ability to generate large bending strain (&amp;gt;5%) and moderate stress at low applied voltages (±2 V). Ionic polymer transducers consist of an ionomer, usually Nafion, sandwiched between two electrically conductive electrodes. A novel fabrication technique denoted as the direct assembly process (DAP) enabled controlled electrode architecture in ionic polymer transducers. A DAP built transducer consists of two high surface area electrodes made of electrically conducting particles uniformly distributed in an ionomer matrix sandwiching an ionomer membrane. The purpose of this paper is to investigate and simulate the effect of these high surface area particles on the electro-chemical response of an IPT. Theoretical investigations as well as experimental verifications are performed. The model used consists of a convection-diffusion equation describing the chemical field as well as a Poisson equation describing the electrical field. The two-dimensional model incorporates highly conductive particles randomly distributed in the electrode area. Traditionally, these kinds of electrodes were simulated with boundary conditions representing flat electrodes with a large dielectric permittivity at the polymer boundary. This model enables the design of electrodes with complicated geometrical patterns. In the experimental section, several transducers are fabricated using the DAP process on Nafion 117 membranes. The architecture of the high surface area electrodes in these samples is varied. The concentration of the high surface area RuO2 particles is varied from 30 vol% up to 60 vol% at a fixed thickness of 30 μm, while the overall thickness of the electrode is varied from 10 μm up to 40 μm at a fixed concentration of 45%. The flux and charge accumulation in the materials are measured experimentally and compared to the results of the numerical simulations. Trends of the experimental and numerical investigations are in agreement, while the computational capacity is limiting the ability to add sufficient amount of metal particle to the electrode in order to match the magnitudes.

Boundary layer charge dynamics in ionic liquid-ionic polymer transducers

Ionic polymer transducers (IPTs), also known as ionic polymer-metal composites, are soft sensors and actuators which operate through a coupling of microscale chemical, electrical, and mechanical interactions. The use of an ionic liquid as solvent for an IPT has been shown to dramatically increase transducer lifetime in free-air use, while also allowing for higher applied voltages without electrolysis. In this work, we apply Nernst-Planck/Poisson theory to model charge transport in an ionic liquid IPT by considering a certain fraction of the ionic liquid ions as mobile charge carriers, a phenomenon which is unique to ionic liquid IPTs compared to their water-based counterparts. Numerical simulations are performed using the finite element method to examine how the introduction of another pair of mobile ions affects boundary layer charge dynamics, concentration, and charge density distributions in the electric double layer, and the overall charge transferred and current response of the IPT. Due to interactions with the Nafion ionomer, not all of the ionic liquid ions will function as mobile charge carriers; only a certain fraction will exist as “free” ions. The presence of mobile ionic liquid ions in the transducer will increase the overall charge transferred when a voltage is applied, and cause the current in the transducer to decay more slowly. The additional mobile ions also cause the ionic concentration profiles to exhibit a nonlinear dynamic response, characterized by nonmonotonic ionic concentration profiles in space and time. Although the presence of mobile ionic liquid ions increases the overall amount of charge transferred, this additional charge transfer occurs in a somewhat symmetric manner. Therefore, the additional charge transferred due to the ionic liquid ions does not greatly increase the net bending moment of the transducer; in fact, it is possible that ionic liquid ion movement actually decreases the observed bending response. This suggests that an optimal electromechanical conversion efficiency for bending actuation is achieved by using an ionic liquid where only a relatively small fraction of the ionic liquid ions exist as free ions. Conversely, if it is desired to increase the overall amount of charge transferred, an ionic liquid with a large fraction of free ions should be used. These theoretical considerations are found to be in good qualitative agreement with recent experimental results.

Ionic polymer transducers in sensing: Implications of the streaming potential hypothesis for varied electrode architecture and loading rate

Explored is the mechanism of streaming potential in the sensing response of ionic polymer transducers, sometimes referred to as ionic polymer metal composites. It is argued that, unlike previous hypotheses, the streaming potential hypothesis is insensitive to the assumed ionomer morphology, and accommodates experimental observation of sensing under shear loading. As demonstration a simplified model for sensing under bending deformation is presented for a material system displaying a cylindrical channel morphology. Specific demonstration scenarios considered include predicting the evolution of sensing with electrode particulate volume fraction and type. In addition, evolution of sensing for both step and oscillatory loading is considered.

Ionic Polymer Transducers in sensing: the streaming potential hypothesis

Accurate sensing of mechanical strains in civil structures is critical for optimizing structure reliability and lifetime. For instance, combined with intelligent control systems, electromechanical sensor output feedback has the potential to be employed for nondestructive damage evaluation. Application of Ionic Polymer Transducers (IPTs) represents a relatively new sensing approach with more than an order of magnitude higher sensitivity than traditional piezoelectric sensors. The primary reason this sensor has not been widely used to date is an inadequate understanding of the physics responsible for IPT sensing. This paper presents models and experiments defending the hypothesis of a streaming potential sensing mechanism.

Oligomeric A2+ B3synthesis of highly branched polysulfone ionomers: novel candidates for ionic polymer transducers

AbstractHighly branched poly(arylene ether sulfone)s with systematically varied degrees of branching and sulfonation were synthesized through oligomeric A2+ B3methods for application as ionic polymer transducer (IPT) membranes. IPTs are a class of electroactive polymer devices that leverage ionomeric membranes to perform electromechanical transduction as actuators and/or sensors. Synthesis of controlled molecular weight A2oligomeric polysulfones targeted the global degree of branching (DBglobal) to approximately 1–3% in the absence of gelation. Size exclusion chromatography confirmed molecular weights greater than 20 000 g mol−1were achieved for linear and branched polysulfones. Increased degree of sulfonation of the A2oligomers reduced the development of molecular weight in the oligomeric A2+ B3branching reaction; the formation of tough, flexible, ion‐conducting membranes is required for emerging transducer applications. Variation in the DBglobalattained did not affect the thermal transitions or elastic modulus as significantly as changes in the degree of sulfonation. However, an ionic dissociation temperature was detected below the glass transition temperature of the polysulfone matrix and was relatively independent of the degree of sulfonation. Successful synthesis and characterization of these well‐defined branched polysulfone ionomers provide a basis for future investigation of polymer topology effects on IPT performance. Copyright © 2009 Society of Chemical Industry

Ionomer design for augmented charge transport in novel ionic polymer transducers

Ionic polymer transducers are devices that display electromechanical transduction and areprojected to have extensive applications as actuators and sensors. This study employsnovel, highly branched sulfonated polysulfones (sBPS) as part of an investigation into thecontribution of polymer topology to electromechanical transduction. Specifically, theionomers are combined with an ionic liquid to determine the optimal ratio and method formaximizing ionic conductivity, where charge transport is essential to device performance.Two uptake methods are assessed for introduction of ionic liquid into the central ionomericmembrane. The effects of casting membranes in the presence of ionic liquid andswelling preformed membranes in ionic liquid on film stability and ionic conductivityare examined. Membranes cast from a solution of the ionomer and ionic liquidallow for direct targeting of the component ratio and a single-step process formembrane formation. Swelling conditions for preformed neat membranes combine time,temperature, and the presence of organic co-diluents to achieve the maximum stableuptake of ionic liquid. Comparison of optimal conditions for the various methodsreveals that swelling with co-diluents achieves ionic conductivity of the imbibedmembrane per uptake higher than the levels achieved with the casting process forhighly sulfonated sBPS. However, for less sulfonated sBPS the casting processsuccessfully produced membranes with ionic conductivities unreachable with theco-diluent process. Both methods will enable the production of high performance ionicpolymer transducers constructed from novel sBPS ionomers and ionic liquids.