Mobility Of Polymer Segments Research Articles

Manipulating Protein Configuration for High-Performance Solid Polymer Electrolytes

Solid polymer electrolytes (SPEs) are well known for their excellent mechanical properties and high safety. It will be significant to develop advanced SPEs for substituting currently used organic liquid electrolytes. However, determined by their ion-transport coupled with mobility of polymer segments, SPEs usually exhibit low ionic conductivity (10-8 ~ 10-6 S/cm) at room temperature, which severely limits their practical applications. Thus far, efforts on enhancing the ionic conductivity of SPEs have been primarily focusing on reducing crystallinity degree of the polymer hosts via introducing plasticizers, advanced nanofillers, other polymers, etc. while there have not existed effective ways to the control of the ion-transport pathways inside the SPEs. In our work, we discovered that by manipulating the configuration of denatured soy protein, the transportation of Li+ can be significantly promoted, which is of great interest for fabricating high-performance SPEs. Via carefully controlling critical factors, including denaturation of soy protein, loading level of lithium salt and temperature for the evaporation process of the electrolyte preparation, a protein-based solid electrolyte with high ionic conductivity (ca. 10-5 S/cm at room temperature) and modulus (ca. 1 GPa) was achieved, which has never been realized in any conventional SPEs. Meanwhile, the soy-protein-based SPE presents high lithium ion transference number of ca. 0.94. Molecular dynamic simulation results indicate that evaporation temperature for electrolyte preparation plays a critical role in controlling the configuration of protein. As a result, a more flexible protein configuration allows strong interactions between anions of lithium salts with the backbone oxygen and negative charge side groups of protein to form anion clusters that can facilitate the transportation of Li+. It is therefore speculated that this unique ion-transport mechanism is ceramic-like and is decoupled with mobility of protein chains. In addition, by introducing ceramic nanoparticles into denaturation of soy protein, the configuration of the protein was dramatically changed to result in a type of highly efficient nanofiller that enables fast ion-transport. A composite polymer electrolyte based on poly(ethylene oxide) (PEO) loaded with such hybrid nanofillers shows one order of magnitude improvement in ionic conductivity at room temperature, as compared with the one with untreated nanofillers. Moreover, the composite polymer electrolyte was demonstrated improved mechanical properties, and importantly improved adhesion properties that greatly benefit interfacial properties with the electrodes. The studies may open a new avenue for developing high-performance SPEs with promoted ion-transport by manipulating the configuration of the protein.

Tunable shape recovery progress of thermoplastic polyurethane by solvents

PurposeThis study aims to present that the chemo-responsive shape recovery of thermoplastic polyurethane (TPU) is tunable by solvents with different solubility parameters, and it is generic for chemo-responsive shape-memory polymer and its composites.Design/methodology/approachTwo kinds of commercial TPU samples with different thicknesses were prepared by panel vulcanizer and injection molding (an industrial manner) to investigate their chemo-responsive shape memory properties in acetic ether and acetone.FindingsResults showed that all of TPU films with different thicknesses can fully recover their original shapes weather they recover in acetic ether or acetone. But the recovery time of TPU films in acetone is greatly reduced, especially for the twisting samples. The residual strains of recovery TPU samples after extension reduce obviously.Research limitations/implicationsThe great decrement of recovery time is related to two factors. One is due to the bigger solubility parameter of acetone with higher dipole moment compared with those of acetic ether, and the other is the remained internal stress of TPU films after preparation. The internal stress is identified to have an effect on the shape-memory properties by comparing the recovery process of samples with/without annealing. The reduced residual strains of recovery TPU samples after extension is due to the increasing mobility of polymer segments after molecules of acetic ether penetrates into the polymeric chains.Originality/valueThis is a universal strategy to control the recovery process of shape-memory materials or composites. The underlying mechanism is generic and should be applicable to chemo-responsive shape-memory polymers or their composites.

Autoacceleration in Bulk Free‐Radical Polymerization: Effect of Chain Transfer

AbstractThe model and methodology for estimating diffusion‐controlled rate coefficients for the methyl methacrylate polymerization system reported in Parts I and II of this series is extended to include the chain transfer reaction to an agent (CTA). Theoretical and experimental results exhibit minima in the rate of polymerization curves at low conversions as it is observed in the absence of CTA. Such minima are proposed to be the onset of the autoacceleration effect where the termination reaction undergoes a transition from chemically controlled to diffusion controlled where the segmental mobility of the chain ends plays a key role. As the CTA concentration increases, the conversion at which the minimum is presented is higher and the autoacceleration is less pronounced. This behavior is explained in terms of the effect of polymer chain entanglements and segmental mobility of the chain ends on the termination rate coefficient k t.

Molecular Mobility and Physical Aging of a Highly Permeable Glassy Polynorbornene as Revealed by Dielectric Spectroscopy

Polymeric membranes represent a cost- and energy-efficient solution for gas separation. Recently superglassy polymers with high free volume outperform many conventional dense polymers in terms of gas permeability and selectivity. However, such polymers are prone to pronounced physical aging, resulting in a dramatic reduction in the gas permeability. Molecular mobility of polymer segments plays an important role in the physical aging and the gas transport performance of polymeric membranes. Molecular mobility and physical aging of a representative superglassy polynorbornene with very high gas permeability, PTCNSi2g, was monitored by using dielectric spectroscopy with state-of-the-art high-resolution analyzers. This work helps to shed some light on the structure–property relationship of superglassy polymers on a molecular level and to provide practical “design rules” for the development of high performance polymers for gas separation.

Effect of Low-Concentration Polymers on Crystal Growth in Molecular Glasses: A Controlling Role for Polymer Segmental Mobility Relative to Host Dynamics.

Low-concentration polymers can strongly influence crystal growth in small-molecule glasses, a phenomenon important for improving physical stability against crystallization. We measured the velocity of crystal growth in two molecular glasses, nifedipine (NIF) and o-terphenyl (OTP), each doped with four or five different polymers. For each polymer, the concentration was fixed at 1 wt % and a wide range of molecular weights was tested. We find that a polymer additive can strongly alter the rate of crystal growth, from a 10-fold reduction to a 10-fold increase. For a given polymer, increasing molecular weight slows down crystal growth and the effect saturates around DP = 100, where DP is the degree of polymerization. For all the systems studied, the polymer effect on crystal growth rate forms a master curve in the variable (Tg,polymer - Tg,host)/Tcryst, where Tg is the glass transition temperature and Tcryst is the crystallization temperature. These results support the view that a polymer's effect on crystal growth is controlled by its segmental mobility relative to the host-molecule dynamics. In the proposed model, crystal growth rejects impurities and creates local polymer-rich regions, which must be traversed by host molecules to sustain crystal growth at rates determined by polymer segmental mobility. Our results do not support the view that host-polymer hydrogen bonding plays a controlling role in crystal growth inhibition.

Role of chemical crosslinking in material-driven assembly of fibronectin (nano)networks: 2D surfaces and 3D scaffolds

Poly(ethyl acrylate) (PEA) induces the formation of biomimetic fibronectin (FN) (nano)networks upon simple adsorption from solutions, a process referred to as material-driven FN fibrillogenesis. The ability of PEA to organize FN has been demonstrated in 2D and 2.5D environments, but not as yet in 3D scaffolds, which incorporate three-dimensionality and chemical crosslinkers that may influence its fibrillogenic potential. In this paper we show for the first time that while three-dimensionality does not interfere with PEA-induced FN fibrillogenesis, crosslinking does, and we determined the maximum amount of crosslinker that can be added to PEA to maintain FN fibrillogenesis. For this, we synthesised 2D substrates with different amounts of crosslinker (1–10% of ethylene glycol dimethacrylate) and studied the role of crosslinking in FN organization using AFM. The glass transition temperature was seen to increase with crosslinking density and, accordingly, polymer segmental mobility was reduced. The organization of FN after adsorption (formation of FN fibrils) and the availability of the FN cell-binding domain were found to be dependent on crosslinking density. Surface mobility was identified as a key parameter for FN supramolecular organization. PEA networks with up to 2% crosslinker organize the FN in a similar way to non-crosslinked PEA. Scaffolds prepared with 2% crosslinker also had FN (nano)networks assembled on their walls, showing PEA’s ability to induce FN fibrillogenesis in 3D environments as long as the amounts of crosslinker is low enough.

Porous crosslinked polycaprolactone hydroxyapatite networks for bone tissue engineering.

In this study, porous scaffolds were produced by a thermal crosslinking of polycaprolactone diacrylate in the presence of hydroxyapatite (HA) and particulate leaching technique with sodium chloride as the water soluble porogen for bone tissue engineering applications. The prepared scaffolds were characterized using techniques such as Field Emission Scanning Electron Microscopy, Differential Scanning Calorimetry, and Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. Moreover, dynamic mechanical properties were investigated using Dynamic Mechanical Thermal Analysis. The obtained scaffolds present a porous structure with interconnected pores and porosity around 73%. It was found that the incorporation of HA particles to polycaprolactone (PCL) matrix resulted in an increased crystallinity. Moreover, both the storage modulus (E') and glass transition temperature (Tg) increased, while the loss factor (tan δ) decreased due to the hindrance of the HA particles to the mobility of polymer segments. Cytocompatability of the scaffolds was assessed by MTT assay and cell attachment studies. Osteoconductivity of the scaffolds was investigated with cells alkaline phosphatase extraction. The levels of alkaline phosphatase activity were found to be higher for PCL/HA network scaffold than for PCL network scaffold. In addition, cytocompatibility of the PCL/HA network scaffold indicated no toxicity, and cells were attached and spread to the scaffold walls.

Silane crosslinking of electrospun poly (lactic acid)/nanocrystalline cellulose bionanocomposite

Biodegradable nanofibrous mats fabricated by electrospinning are commonly used in tissue engineering, however, lack of essential mechanical properties of such nanofibers is a challenging issue. In this work, vinyltrimethoxysilane (VTMS) was grafted onto poly (lactic acid) (PLA) and the silane grafted PLA was subsequently applied in electrospinning process. Electrospun nanofibrous mats based on PLA/nanocrystalline cellulose (NCC) and PLA-g-silane/NCC nanocomposites were fabricated and immersed in hot water (70°C) for crosslinking of silane grafted PLA. It was found that introducing NCC to the samples cause to reduction in fiber diameter and the other hand the silane crosslinking of PLA increase the mean fiber diameter. DSC thermograms also revealed that silane grafting caused a reduction in mobility of polymer segments, and consequently reduction of crystallinity. On the contrary, the NCC in the PLA-g-silane samples effectively influenced the crystal nucleation, while in the PLA nanofibers the nucleation was lower. The impact of NCC on tensile strength enhancement of samples was notable. The results suggested that the chemical crosslinking remarkably improves the mechanical properties of PLA nanofibers. Furthermore, biocompatibility of such modified nanofibers was also evaluated through cytotoxicity results, therefore the modified PLA nanocomposite can be considered as a practical candidate for hard tissue engineering applications.

Preferential Stereocomplex Crystallization in Enantiomeric Blends of Cellulose Acetate-g-Poly(lactic acid)s with Comblike Topology.

Although stereocomplex (sc) crystallization is highly effective for improving the thermal resistance of poly(lactic acid) (PLA), it is much less predominant than homocrystallization in high-molecular-weight (HMW) poly(l-lactic acid)/ poly(d-lactic acid) (PLLA/PDLA) racemic blends. In this contribution, the sc crystallization of HMW PLLA/PDLA racemic blends was facilitated by using comblike PLAs with cellulose acetate as the backbone. Competing crystallization kinetics, polymorphic crystalline structure, and structural transition of comblike PLLA/PDLA blends with a wide range of MWs were investigated and compared with the corresponding linear/comblike and linear blends. The HMW comblike blend is preferentially crystallized in sc polymorphs and exhibits a faster crystallization rate than does the corresponding linear blend. The sc crystallites are predominantly formed in nonisothermal cold crystallization and isothermal crystallization at temperatures above 120 °C for the comblike blends. Except for the facilitated sc formation in primary crystallization, synchrotron radiation WAXD analysis indicates that the presence of a comblike component also facilitates the transition or recrystallization from homocrystallite (hc) to sc crystallite upon heating. Preferential sc formation of comblike blends is probably attributable to the favorable interdigitation between enantiomeric branches and the increased mobility of polymer segments. After crystallization under the same temperature, the comblike blends, which mainly contain sc crystallites, show smaller long periods and thinner crystalline lamellae than do the corresponding PLLA with homocrystalline structures.

Bilayered (silica–chitosan) coatings for studying dye release in aqueous media: The role of chitosan properties

Chitosan and bilayered – Rhodamine 6G impregnated silica–chitosan – coatings (300–3000nm thick) were prepared and investigated as a model for controlled drug release. Properties of native, ionically (sodium triphosphate) and covalently (glutaraldehyde) cross-linked layers of chitosan in contact with aqueous phase (modeling human blood pH of ca. 7.3) were investigated. The cross-linking was confirmed by attenuated total reflection (ATR) Fourier transform infrared (FTIR), energy-dispersive spectroscopy (EDS) and solid state 13C nuclear magnetic resonance (NMR) spectroscopy. The evolution of advancing water contact angles as a function of time was measured, and from the results restricted mobility of polymer segments in the interfacial layer of cross-linked chitosan coatings were assumed. Spectroscopic ellipsometry measurements showed that covalent cross-linking leads to a lowered, while ionic cross-linking to an increased swelling degree of chitosan layers. Despite the swelling behavior both cross-linked chitosan layers showed significant retard effect on dye release from the bilayered coatings.

Manipulating the glass transition behavior of sulfonated polystyrene by functionalized nanoparticle inclusion.

Nanoscale interfaces can modify the phase transition behaviors of polymeric materials. Here, we report the double glass transition temperature (Tg) behavior of sulfonated polystyrene (sPS) by the inclusion of 14 nm amine-functionalized silica (NH2-SiO2) nanoparticles, which is different from the single Tg behaviors of neat sPS and silica (SiO2)-filled sPS. The inclusion of 20 wt% NH2-SiO2 nanoparticles results in an increase of Tg by 9.3 °C as well as revealing a second Tg reduced by 44.7 °C compared to the Tg of neat sPS. By contrast, when SiO2 nanoparticles with an identical concentration and size to NH2-SiO2 are dispersed, sPS composites possess a single Tg of 7.3 °C higher than that of the neat sPS. While a nanoscale dispersion is observed for SiO2 nanoparticles, as confirmed by microscopic and X-ray scattering analyses, NH2-SiO2 nanoparticles show the coexistence of micron-scale clustering along with a nanoscale dispersion of the individual nanoparticles. The micro-phase separation contributes to the free volume induced Tg reduction by the plasticization effect, whereas the Tg increase originates from the polymer segment mobility constrained by nanoconfinement and the rigid amorphous fractions deriving from strong polymer-particle interactions.

Analysis of pH-dependent Structure and Mass Transfer Characteristics of Polydopamine Membranes by Molecular Dynamics Simulation

Detailed atomistic structures are constructed for polydopamine membranes containing different amounts of catechol and quinone groups to investigate the effect of pH value in the membrane casting solution on sorption and diffusion of small gas molecules (water and propylene) in the membranes. Interactions between dopamine oligomers are calculated, and it is found that the interactions decrease from −2356.52kJ·mol−1 in DOP-1 to −1586.69kJ·mol−1 in DOP-3 when all of the catechol groups are converted to quinone groups. The mobility of polymer segments and free volume properties of polydopamine membranes are analyzed. The sorption quantities of water and propylene in the membrane are calculated using Grand Canonical Monte Carlo method. The sorption results show that water adsorbed in DOP-1, DOP-2 and DOP-3 are 17.3, 18.6 and 20.0mg water per gram polymer, respectively, and no propylene molecule can be adsorbed. The diffusion behavior of water molecules in the membrane is investigated by molecular dynamics simulation. The diffusion coefficients of water molecules in DOP-1, DOP-2 and DOP-3 membranes are (1.80±0.52)×10−11, (3.40±0.64)×10−11 and (4.50±0.92)×10−11m2·s−1, respectively. The predicted sorption quantities and diffusion coefficients of water and propylene in the membrane present the same trends as those from experimental results.

Poly(ε-caprolactone)-based polymer electrolyte for electrical double-layer capacitors

The potential of electrical double-layer capacitors (EDLCs) fabricated from symmetry activated carbon electrodes and poly(ε-caprolactone) (PCL)-based polymer electrolytes (PE) have been studied. PEs that consisted of PCL, ammonium thiocyanate, and ethylene carbonate (EC) were prepared by solution casting. In this system, EC was added as a plasticizing solvent to improve the conductivity. The room temperature ionic conductivity of PE increased from 3.94 × 10−7 S cm−1 to 3.8 × 10−5 S cm−1 at 50 wt% EC. In the structural studies carried out by X-ray diffraction, it was found that addition of EC reduces the degree of crystallinity of the entire system. Temperature-dependent conductivity studies showed that Vogel–Tamman–Fulcher model fits very well with regression value close to unity. This observation demonstrates a close coupling between the ionic motion and the polymer segment mobility. The preliminary result of EDLC cell was evaluated by cyclic voltammetry. The single-electrode specific capacitance of EDLC is obtained to be 42.4 F g−1.

Effect of free volume redistribution on the diffusivity of water and benzene in poly(vinyl alcohol)

We used molecular dynamics simulation to study the diffusion of two selected penetrants, water and benzene, in poly(vinyl alcohol) (PVA) over a wide range of temperatures and concentrations to gain insights into their diffusion mechanisms under different conditions. To help understand the effect of free volume on the diffusion behavior of water and benzene, we used the technique of Voronoi tessellation to determine key characteristics of free volume redistribution. Unlike the Connolly surface analysis method, Voronoi tessellation yields information not only on the mean fractional free volume but also on the size distribution of the free volume surrounding each penetrant molecule and its time evolution. In the case of water, we showed that it was the free volume redistribution frequency that led to an observation, previously reported in the literature, that the self-diffusion coefficient of water increases with increasing water concentration despite the fact that increase in water concentration decreases the mean fractional free volume in PVA. In the case of benzene (non-polar) diffusing in PVA (polar), we demonstrated that the failure of the Macki–Meares model was not entirely due to the dissimilarity between the intermolecular interactions. Rather, one of the reasons was the inability of the benzene molecules to break the hydrogen bonds between the PVA chains which are essential to increase the polymer segments mobility. Higher polymer segmental mobility is needed to create larger fluctuations in free volume holes for benzene to diffuse. This would in turn prevent the benzene molecules, with a relatively larger size compared to water molecules, from diffusing by a fluid-like streaming mechanism that is required by the model. In fact, the Macki–Meares model also failed for water at low temperatures and concentrations, as water diffused by a hopping mechanism under such conditions.

Examination of the fundamental relation between ionic transport and segmental relaxation in polymer electrolytes

Replacing traditional liquid electrolytes by polymers will significantly improve electrical energy storage technologies. Despite significant advantages for applications in electrochemical devices, the use of solid polymer electrolytes is strongly limited by their poor ionic conductivity. The classical theory predicts that the ionic transport is dictated by the segmental motion of the polymer matrix. As a result, the low mobility of polymer segments is often regarded as the limiting factor for development of polymers with sufficiently high ionic conductivity. Here, we show that the ionic conductivity in many polymers can be strongly decoupled from their segmental dynamics, in terms of both temperature dependence and relative transport rate. Based on this principle, we developed several polymers with “superionic” conductivity. The observed fast ion transport suggests a fundamental difference between the ionic transport mechanisms in polymers and small molecules and provides a new paradigm for design of highly conductive polymer electrolytes.

Supercritical carbon dioxide-assisted silanization of multi-walled carbon nanotubes and their effect on the thermo-mechanical properties of epoxy nanocomposites

Supercritical carbon dioxide was employed as the solvent for the functionalization of multi-walled carbon nanotubes (MWCNTs) with an epoxy-capped silane. The silanization protocol was found to be a suitable green alternative to traditional routes that rely on organic solvents for grafting nearly monolayers of silane molecules onto the nanotube surfaces. The addition of silanized MWCNTs to a model epoxy markedly increased its Tg, and measurements of the network cooperativity length scale linked this change to a reduction in polymer segment mobility. Composites filled with low loading levels of both pristine and silanized MWCNTs exhibited significantly higher strain at break and toughness than the neat epoxy, and the greatest improvements were observed at low loading levels. SEM analysis of the composite fracture surfaces revealed that nanotube pullout was the primary failure mechanism in epoxy loaded with pristine MWCNTs while crack bridging predominated in composites containing silanized MWCNTs as the result of strong interfacial bonding with the matrix. The elevated Tg and toughness achieved with small additions of silanized MWCNTs promise to extend the engineering applications of the epoxy resin.

Nanoconfinement of Ionic Liquid and Polymers in Supported Thin Films: A Time-of-Flight Secondary Ion Mass Spectrometry Study of Surface Diffusion

To gain insights into properties of a room-temperature ionic liquid in confined geometry, 1-ethyl-3-methylimidazolium bis[trifluoromethanesulfonyl]imide ([emim][Tf2N]) adspecies interacting with various substrates was investigated as a function of temperature by using time-of-flight secondary ion mass spectrometry. The monolayer of adspecies is incorporated into substrates of porous Si, self-assembled monolayers, and Li[Tf2N] at 180–190 K that is slightly greater than the bulk glass transition temperature, Tg, of [emim][Tf2N]. In contrast to simple glass formers, no surface diffusivity is observed for [emim][Tf2N] in the sub-Tg region. The uptake of [emim][Tf2N] into polymer films is associated with the surface mobility of polymer segments rather than adspecies. The mobility of poly(methyl methacrylate) is not quenched by hydrogen bonds with the substrate, as evidenced by that the uptake onset of [emim][Tf2N] is almost independent of the polymer film thickness.

Silica phase formed by sol–gel reaction in the nano- and micro-pores of a polymer hydrogel

Hybrid composites consisting in a hydrogel matrix with silica micro- and nano-particle reinforcement were produced and characterized. The strategy proposed here to obtain them consisted in a two-step synthesis being the polymer network formation the first step. Porous poly(hydroxyethyl acrylate) hydrogel network was produced by radical polymerization of the monomer diluted in different amounts of ethanol. Polymeric microstructure drives the absorption of a silica precursor solution and the further distribution of the inorganic phase that is formed in situ. A fraction of the resulting silica phase occupies the pores and the other part is in the form of nanoparticles dispersed in the polymer phase. Composites with silica content up to ~60% by weight were obtained. Silica phase is continuous and samples maintain their integrity after eliminating the organic phase by pyrolysis. Dependence of hybrid microstructure in compliance, water sorption capacity, bioactivity and the effect of silica content in polymer segmental mobility were assessed.

Molecular Weight Effects on Particle and Polymer Microstructure in Concentrated Polymer Solutions

Microstructure of particles and polymers in concentrated polymer solutions are examined. Silica nanoparticles with diameters of 44 nm are suspended in concentrated poly(ethylene glycol) (PEG) solutions working with PEG molecular weights from 300 to 20 000. Using time-domain NMR, we explore the effects of PEG adsorption on the silica particles on the mobility of polymer segments. Our results reveal that polymer mobility varies from the particle surface to the bulk with different relaxation times; polymers are glassy near the particle surface and mobile in the bulk. While polymer segments adsorb to the particle surfaces to form a glassy layer in a molecular weight independent manner, the number of polymer segments with intermediate mobility between that of the glassy state and the bulk increases with molecular weight. Systematic variations in the nanoparticle and polymer microstructure in concentrated polymer solutions are explored using contrast-matching small angle neutron scattering techniques demonstrat...

Effect of ethylene carbonate on proton conducting polymer electrolyte based on poly(ε-caprolactone) (PCL)

Polymer electrolytes (PE) comprised of poly(e-caprolactone) (PCL), ethylene carbonate (EC) and ammonium thiocyanate (NH4SCN) were prepared by solution casting. Thermal properties, conductivity and structural studies were characterized by differential scanning calorimetry (DSC), impedance spectroscopy and X-ray diffraction (XRD), respectively. EC is intended to be used as plasticizing solvent to enhance the conductivity. It is found later that EC can also promote ion dissociation in polymer electrolyte system. From DSC studies, the introduction of EC as additive into PCL-NH4SCN complexes reduces the Tm from 56.4 °C to 44.1 °C, drops Tg from − 59.7 °C to − 76.7 °C and suppresses the crystallinity. The conductivity of PE improves from 4.6 × 10− 8 S cm− 1 to 3.8 × 10− 5 S cm− 1 at 50 wt.% EC. Relative permittivity studies show that EC contributes to higher dissociation rate of charge ions. In the temperature dependence conductivity analysis, VTF equation fits very well with regression value close to unity for all the samples demonstrating a close coupling between the conductivity and the polymer segment mobility. The pre exponential factor A increases as more EC is added, reflecting the growth in the number of charge carriers. Structural analysis using XRD displays an apparent reorganization of polymer matrix due to the EC effect. This is in agreement with DSC and EIS observations. Degree of crystallinity calculated using XRD two phase model shows a decrease from 32.7% of zero EC to 16.0% of 50 wt.% EC. These results are comparable to the DSC analysis.