PEO Blend Research Articles

Preparation and characterization of poly(ethylene oxide)‐loaded hydroxypropyl‐β‐cyclodextrin nanofibers

Hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) is a modified β‐cyclodextrin (β‐CD) derivative, which is toxicologically harmless to mammals and other animals. HP‐β‐CD is electrospun from an aqueous solution by blending with a non‐toxic, biocompatible, synthetic polymer poly(ethylene oxide) (PEO). Aqueous solutions containing different HP‐β‐CD/PEO blends (50:50–80:20) with variable concentrations (4 wt%–12 wt%) were used. Scanning electron microscope was used to investigate the morphology of the fibers, and Fourier transform infrared spectroscopy analysis confirmed the presence of HP‐β‐CD in the fiber. Uniform nanofibers with an average diameter of 264, 244, and 236 nm were obtained from 8 wt% solution of 50:50, 60:40, and 70:30 HP‐β‐CD/PEO, respectively. The average diameter of the fiber was decreased with increasing of HP‐β‐CD/PEO ratio. However, a higher proportion of HP‐β‐CD in the spinning solution increased beads in the fibers. The polymer concentration had no significant effect on the fiber diameter. The most uniform fibers with the narrowest diameter distribution were obtained from the 8 wt% of 50:50 solution. Copyright © 2015 John Wiley & Sons, Ltd.

Miscible crystalline/crystalline polymer blends of polyoxymethylene copolymer/poly(ethylene oxide) with interpenetrated spherulites and enhanced properties

Miscibility and crystallization behavior of a polymer blend consisting of two crystalline components, polyoxymethylene copolymer (Co‐POM) and poly(ethylene oxide) (PEO), have been investigated. Experimental results indicate that Co‐POM is thermodynamically miscible with PEO, as shown by the existence of single‐composition dependent glass transition temperature over the entire composition range. The crystal structures and spherulitic morphologies of (Co‐POM)/PEO blends were studied by X‐ray diffraction, differential scanning calorimetry, scanning electron microscopy, and polarizing light microscopy. It was found that the PEO spherulites crystallized within the matrix of the crystals of the pre‐existing Co‐POM phase and resulted in a high extent of interfibrillar segregation. The unique interpenetrated crystalline structure was beneficial for the sufficient contact between the two components and significantly improved both the toughing and the lubricating effect of PEO on the POM matrix. On incorporation of 30 wt% PEO, the notched impact strength of POM was enhanced from 6.7 to 10.3 MPa, by about 53.7%, while the elongation at break increased from 28.5% to 121.0%, by about 3.2 times. Furthermore, the friction coefficient drastically decreased from 0.35 to 0.17, demonstrating the enhanced tribological performance of the miscible blends. J. VINYL ADDIT. TECHNOL., 22:479–486, 2016. © 2015 Society of Plastics Engineers

Crystallization behavior of disproportionately high and low molecular weight PEO blends

The crystallization behavior of PEOs with molecular weight of 10k and 200k as well as their blends was studied in details. The results show that the lower molecular weight PEO crystallizes with faster crystallization rate as judged from a shorter time for completing the crystallization. On the other hand, the higher molecular weight PEO crystallizes at relatively higher temperature, indicating an early start of crystallization compared with the lower molecular weight one. The blends of these two PEOs with different blend ratios always cocrystallize during the cooling processes. It is confirmed that mixing of the 10k PEO with the 200k one is in favor of the crystallization of the system. This is not only demonstrated by the early start of the crystallization at higher crystallization temperature, and also a faster crystal growth of the blend with respect to the 200k PEO. The crystallization of the blends at higher temperature is caused by an early start of nucleation and an increment of nucleus density. This may originate from the density fluctuation of the blend and a reduction in energy barrier for nucleation. Moreover, it is found that the crystallinity of the 10k PEO rich blends increases with increasing concentration of the 10k PEO. This is caused by the solvent effect of the 10k PEO toward the 200k PEO. On the other hand, the crystallinity of the 30/70 (10k/200k) PEO blend is decreased a little bit. This may be a balanced result of the improved crystallization of the 200k PEO at the expense of the high crystallization ability of the 10k PEO.

Threading of Ring Poly(ethylene oxide) Molecules by Linear Chains in the Melt.

We report results from an atomistic molecular dynamics simulation study of ring-linear poly(ethylene oxide) (PEO) melts followed by a topological reduction to ensembles of primitive paths and a detailed geometric analysis using vector calculus, which reveals considerable cyclic threading by the linear chains. The simulations have been conducted using ring-linear PEO blends of the same size, over a series of molecular lengths and compositions. For PEO melts characterized by molecular weight (MW) greater than 10044 g/mol, in particular, our computations reveal the occurrence of multiple threading events (penetrations). We further find that the time it takes a linear molecule that threads a cyclic one to fully pass through the latter can be more than 1 order of magnitude larger than the corresponding relaxation time of the ring in its own melt. Our analysis implies that dynamics in ring-linear polymer blends is highly heterogeneous, with many of the threadings being long-lived and with the linear chains (even when present in small amounts) dramatically obstructing the mobility of rings.

Investigation of a Nanocomposite of 75 wt % Poly(methyl methacrylate) Nanoparticles with 25 wt % Poly(ethylene oxide) Linear Chains: A Quasielatic Neutron Scattering, Calorimetric, and WAXS Study

We have investigated the thermal behavior, local structure, and dynamics in a system where 25 wt % PEO [poly(ethylene oxide)] linear chains are mixed with 75 wt % PMMA [poly(methyl methacrylate)] soft nanoparticles. Calorimetric and wide-angle X-ray scattering experiments point to a weak penetration of the PEO chains in the nanoparticles, qualifying the mixture as a nanocomposite. Quasi-elastic neutron scattering (QENS) experiments on partially deuterated samples has selectively revealed the component dynamics in the system. The α-methyl group dynamics of PMMA, which fall within the QENS time scale in the temperature range investigated, are hardly affected by the presence of PEO except for hints of a more heterogeneous environment in the nanocomposite than in bulk PMMA. The effects on the dynamics of PEO are more interesting. The observation of dynamics in the microseconds range for the PEO component of the nanocomposite at temperatures at which the calorimetric experiments indicate the freezing of its segmental relaxation provides evidence for confined dynamics below the main glass transition of the mixture—attributable to the effective glass transition of the slow component. A parallel study on an equivalent blend of PEO and linear PMMA chains shows that these effects are independent of the topology of the PMMA. However, well above the effective glass transition of the slow component, the dynamics of PEO differ in both systems. In the linear blend, PEO segments move with the typical features of supercooled polymers in metastable equilibrium, while in the nanocomposite PEO dynamics exhibit an anomalously strong deviation from Gaussian behavior. This deviation grows with increased mobility of the nanoparticles. PEO segments are seemingly trapped in effective cages imposed by the nanoparticles for a very long time—more than 2 orders of magnitude longer than in bulk or when surrounded by linear PMMA chains—before the subdiffusive process leading to segmental relaxation sets in. We speculate that local loops in the surface of the nanoparticles may play an important role in this trapping mechanism.

Effect of swift heavy O7+ ion radiations on conductivity of lithium based polymer blend electrolyte

In the present work, effect of swift heavy O7+ ion of 80MeV of different fluences, on conductivity of [PVA(47.5)–PEO(47.5)–LiCF3SO3(5)]–EC(8) polymeric films has been investigated using ac impedance spectroscopy. The power law exponent n, hopping frequency ωh and activation energies for conduction Eac and relaxation Ear, have been investigated for different fluences. The DSC measurements are carried out in order to investigate the variations in the degree of crystallinity and thermal parameters (Tm) of the blend specimen prior and after irradiation. The Fourier Transform Infrared (FT-IR) measurements are carried out in order to investigate the changes in the vibrational modes of molecules upon irradiation. The FT-IR measurements corroborate the formation of amorphous phase in the blend matrix after irradiation. The conductivity is found to be optimum at the fluence of 1×1012ions/cm2. The enhancement and the improvement in the electrolytic properties of PVA–PEO blend upon O7+ ion irradiation have been observed.

PEO를 이용한 Alg-Na 바인더의 물성향상

There has been increasing demand to the eco-friendly materials such as phytoncide which is extracted to plants in the textile industry, recently. It is interesting that alginic acid sodium salt(Alg-Na) is used to eco-friendly binder for the functional capsule finishing. In this study, we made PEO/Alg-Na blend solutions of various ratio and observed the changing binding property of the blend solutions according to PEO contents through FT-IR, DSC, contact angle, peel strength, etc. The viscosity of Alg-Na/PEO blend solutions increased with increase of contents and the viscosity quickly increased with increase of PEO content in Alg-Na 5% content, specially. It is shown that the hydrogen bond peak by blend of Alg-Na and PEO found through FT-IR analysis but the peak decreased in PEO above 60% content. And the peel strength was predominant in PEO 50% ratio.

Graphene oxide sheet–polyaniline nanohybrids for enhanced photovoltaic performance of dye‐sensitized solar cells

ABSTRACTIn this study, photovoltaic (PV) properties of dye‐sensitized solar cells (DSSCs) incorporated with graphene oxide nanosheet‐polyaniline (GOS‐PANI) nanohybrid/poly(ethylene oxide) (PEO) blend gel electrolytes were investigated. Chemical structure and composition of GOS‐PANI nanohybrids were characterized by Raman spectroscopy and X‐ray photoelectron spectroscopy. The images of transmission electron microscopy revealed that PANI nanorods were anchored to the single‐layered GOS for the GOS‐PANI nanohybrids. Ionic conductivities of the GOS‐PANI/PEO–based gel electrolytes were measured using a conductivity meter. The electrochemical catalytic activities of the GOS‐PANI nanohybrids were determined through cyclic voltammetry. These GOS‐PANI nanohybrids were served as the extended electron transfer materials and catalyst for the electrochemical reduction of I3−. Due to the enhancement of the ionic conductivity and electrochemical catalytic activity of the gel electrolyte, better PV performance was observed for the DSSCs based on the GOS‐PANI containing electrolytes as compared to the pristine PEO electrolyte‐based DSSC sample. Moreover, PV performances of the GOS‐PANI/PEO–based DSSCs were closely related to the PANI content of GOS‐PANI nanohybrids. The highest photo‐energy conversion efficiency (5.63%) was obtained for an optimized GOS‐PANI/PEO (5:95, w/w) blend gel electrolyte‐based DSSC sample. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 321–332

Formation behavior and performance studies of novel antifouling EVAL/PEO–PPO–PEO blend membranes for oil/water separation

Novel anti-fouling poly (ethylene-co-vinyl alcohol)/polyethylene oxide-polypropylene oxide-polyethylene oxide (EVAL/PEO–PPO–PEO) blend membranes were prepared by immersion precipitation method with different EVAL/PEO–PPO–PEO ratios. Thermodynamic and kinetic parameters which govern the formation of membrane were studied by viscosity and precipitation kinetics. Polyethylene oxide–polypropylene oxide–polyethylene oxide (PEO–PPO–PEO) content in the membrane solution controls phase separation by thermodynamic enhancement and kinetic hindrance. The addition of PEO–PPO–PEO is favorable for the formation of spongy like pores and higher porosity surface, which results in larger water flux and higher oil rejection rate through the membrane. Improved hydrophilicity and fouling resistance which have great significance in oil/water separation field were observed by the presence of PEO–PPO–PEO in the membrane. Fourier transform infrared spectroscopy results proved the residual PEO–PPO–PEO in the blend membranes.

Confined Nucleation and Growth of Poly(ethylene oxide) on the Different Crystalline Morphology of Poly(butylene succinate) From a Miscible Blend

The confined and fractional crystallization behavior of poly(ethylene oxide)(PEO) in miscible poly(butylene succinate)(PBS)/PEO blends has been investigated. Both nucleation and growth of PEO cryst...

Alignment Nanofibers Conducting Polymer (PAni.CSA/PEO) Preparation by Electrospinning Technique

Importance of different concentration parameter was evaluated in electrospinning of PAni.CSA/PEO Blends, The alignment nanofibers of this blends were successfully fabricated using electrospinning technique. Morphology and diameters of the nanofibers were studied by Atomic Force Microscope (AFM). The diameter of nanfiber was about 40.49 nm (at 8 wt% PEO concentration) and increased with increasing concentration to 92.35 nm (at 30 wt% PEO concentration). Structural characteristics of the electrospuning nanofibers and the formation of functional group of PEO polymer and the PAni.CSA were predicted by the FT-IR spectra. X-ray diffraction (XRD) showed crystalline peaks of the PAni.CSA/PEO blends. The PAni.CSA/PEO blends containing up to the 8 wt% PEO could be electrospun into the continuous fibers structure, although pure PAni.CSA solution was not able to be electrospuning into the fibrous structure.

Proton conducting polymer electrolyte based on plasticized chitosan–PEO blend and application in electrochemical devices

Plasticized chitosan–poly(ethylene oxide) (PEO) doped with ammonium nitrate (NH4NO3) electrolyte films are prepared by the solution cast technique. From Fourier transform infrared (FTIR) spectroscopy analysis, hydroxyl band of pure chitosan film is shifted from 3354 to 3425cm−1 when blended with PEO. On addition of 40wt.% NH4NO3, new peaks at 3207cm−1 and 3104cm−1 appear in the hydroxyl band region, indicating the polymer-salt complexation. The carboxamide and amine bands are observed to shift to 1632 and 1527cm−1, respectively. The interaction of chitosan–PEO–NH4NO3–EC can be observed by the appearance of the doublet CO stretching band of EC. The sample with 70wt.% ethylene carbonate (EC) exhibits the highest room temperature conductivity of (2.06±0.39)×10−3Scm−1. This result is further verified by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) studies. Proton battery is fabricated and shows an open circuit potential (OCP) of (1.66±0.02) V and average discharge capacity at (48.0±5.0)mAh. The maximum power density of the fabricated cell is (9.73±0.75)mWcm−2. The polymer electrolyte is also employed as separator in electrical double layer capacitor (EDLC) and is cycled for 140 times at room temperature.

Electrospinning of a blend of a liquid crystalline polymer with poly(ethylene oxide): Vectran nanofiber mats and their mechanical properties

Vectran® is a liquid crystalline polymer (LCP) with remarkable specific properties in its commercial microfiber form. Even though it has been widely studied in the last few decades, there have been no reports in the literature on Vectran nanofibers production. Due to the insufficient spinnability of Vectran, a “host–guest” method with poly(ethylene oxide) (PEO) as a host polymer is used in the present work to produce continuous and uniform nanofibers of Vectran–PEO blends. Subsequently, a heat treatment is applied and optimized to remove PEO and convert the amorphous Vectran–PEO nanofibers into more ordered and mechanically improved pure Vectran nanofibers. The conclusions are supported by scanning electron microscopy, thermal analysis, selected area electron diffraction (SAED) patterns and mechanical characterization of electrospun Vectran nanofiber mats after removal of PEO.

Sodium alginate/poly (ethylene oxide) blend hydrogel membranes for controlled release of valganciclovir hydrochloride

Sodium alginate (SA) and poly (ethylene oxide) PEO blend membranes were prepared by solvent casting method for the controlled release of valganciclovir hydrochloride, an antiHIV drug. The prepared membranes were thin, flexible, smooth, and characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), X-ray diffraction (X-RD), scanning electron microscopy (SEM), and tensile strength measurement. FTIR was used to understand the formation of hydrogen bonding between SA and PEO. The DSC and X-RD studies were performed to understand the crystalline nature of drug after encapsulation into the membranes. SEM was used to study the surface morphology of the membranes. Tensile strength measurements revealed the mechanical strength of the membranes. In vitro release studies indicated a dependence of release rate on the extent of crosslinking, amount of drug loading, and the amount of PEO, but slow release rates was extended up to 12 h. Cumulative release data were fitted onto to an empirical equation to compute diffusional exponent (n), which indicated the nonFickian trend for drug release.

Preparation and characterization of polyvinyl alcohol‐polyethylene oxide‐carboxymethyl cellulose blend membranes

AbstractIn this study, blends of poly(vinyl alcohol) (PVA) and poly(ethylene oxide) (PEO) were prepared by solution casting method to develop membranes. The addition of carboxymethyl cellulose (CMC) led to the stabilization of PVA and PEO blend system. PVA/PEO/CMC membranes of three compositions 90/10/5, 90/10/10, and 90/10/20 were prepared and were characterized by X‐ray diffraction (XRD), thermogravimetric analysis, differential scanning calorimetry (DSC), and attenuated total reflectance‐Fourier transform infra‐red. It was found that the addition of CMC to PVA/PEO blend leads to significant visible changes in the miscibility of these two components. Swelling of blend membranes increased with the increase in concentration of CMC. The thermal stability and mechanical strength of the blended samples increased with increasing CMC content when compared with pure PVA and PVA/PEO blends. XRD and DSC showed decrease in crystallinity with the increase in CMC content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The Effect of Thermal Pretreatments on the Mechanical Properties of the Blend Consisting of Poly(Ethyl Methacrylate) and Poly(Ethylene Oxide)

The solution cast technique for the preparation of polymer blends of poly(ethylmethacrylate) (PEMA) and poly(ethylene oxide)(PEO) is described. Polymer blends of poly(ethylmethacrylate) (PEMA) and poly(ethylene oxide) (PEO) with different weight percentage ratio of the two polymers have been prepared. Effect of thermal pretreatments like annealing and quenching on the mechanical properties of polymer blends of PEMA and PEO have been reported using Vicker's microhardness testing. The thermal pretreatment produces morphological changes in the blend system investigated. These thermal pretreatments results in hardening and softening of blend systems under investigation.

Interchain coupled chain dynamics of poly(ethylene oxide) in blends with poly(methyl methacrylate): Coupling model analysis

Quasielastic neutron scattering and molecular dynamics simulation data from poly(ethylene oxide) (PEO)/poly(methyl methacrylate) (PMMA) blends found that for short times the self-dynamics of PEO chain follows the Rouse model, but at longer times past t(c) = 1-2 ns it becomes slower and departs from the Rouse model in dependences on time, momentum transfer, and temperature. To explain the anomalies, others had proposed the random Rouse model (RRM) in which each monomer has different mobility taken from a broad log-normal distribution. Despite the success of the RRM, Diddens et al. [Eur. Phys. Lett. 95, 56003 (2011)] extracted the distribution of friction coefficients from the MD simulations of a PEO/PMMA blend and found that the distribution is much narrower than expected from the RRM. We propose a simpler alternative explanation of the data by utilizing alone the observed crossover of PEO chain dynamics at t(c). The present problem is just a special case of a general property of relaxation in interacting systems, which is the crossover from independent relaxation to coupled many-body relaxation at some t(c) determined by the interaction potential and intermolecular coupling/constraints. The generality is brought out vividly by pointing out that the crossover also had been observed by neutron scattering from entangled chains relaxation in monodisperse homopolymers, and from the segmental α-relaxation of PEO in blends with PMMA. The properties of all the relaxation processes in connection with the crossover are similar, despite the length scales of the relaxation in these systems are widely different.

Poly(ethylene oxide) : succinonitrile—a polymeric matrix for fast-ion conducting redox-couple solid electrolytes

A blend of poly(ethylene oxide), PEO, and succinonitrile, SN, was investigated for the first time for applying it as a polymeric matrix of low-cost and thermally stable fast-ion conducting redox-couple solid polymer electrolytes. The PEO–SN blend in equal weight fraction showed room temperature ionic conductivity of 1 × 10−8 S cm−1 with nearly two orders of magnitude higher than that of PEO due to reduced crystallinity. The blend resulted in a solid electrolyte with improved ionic conductivity of ∼7 × 10−4 S cm−1 at 25 °C. The blend and its electrolyte showed thermal stability up to 100 °C, which is essential for outdoor application of dye-sensitized solar cells.

Morphology Development in Relation to the Ternary Phase Diagram of Biodegradable PDLLA/PCL/PEO Blends

AbstractThe morphology phase diagram of biodegradable polymer blends of PDLLA, PCL, and PEO is presented and discussed. The phase diagram of PCL/high‐molecular‐weight PDLLA mixtures reveals an hour‐glass phase diagram. Upon lowering the molecular weight of PDLLA, a combined LCST/UCST develops that is intersected by the melting transition curve of PCL. The observed liquid/liquid phase separation and crystal/isotropic phase transition are compared with the theoretical liquidus/solidus curves obtained by solving the combined Flory‐Huggins and phase‐field free energies self‐consistently. A similar study is extended to the binary phase diagrams of PEO/PDLLA and PCL/PEO. Of particular interest is that the prism‐type phase diagram of the ternary blends provides a complete description of the overall phase behavior. magnified image

Enhanced photovoltaic performance of quasi-solid-state dye-sensitized solar cells via incorporating quaternized ammonium iodide-containing conjugated polymer into PEO gel electrolytes

In this study, a series of gel electrolytes prepared from blends of alternating conjugated polymer electrolytes (CPEs)/poly(ethylene oxide) (PEO) were developed for use in quasi-solid-state dye-sensitized solar cells (DSSCs). The alternating CPEs poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(9,9-dioctyl-2,7-fluorene)]diiodide, poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(9,9-bis(2-(2-methoxyethoxy)ethyl)-2,7-fluorene)]diiodide (MPCFO-E), and poly[(N-(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-3,6-carbazole)-alt-(siloxane substituted-2,7-fluorene)]diiodide (MPCFS-E) were synthesized through copolymerization of carbazole units (featuring quaternized ammonium iodide groups) and fluorene units featuring flexible side chains (9,9-dioctylfluorene, ethylene oxide-substituted fluorene, and siloxane-substituted fluorene, respectively). The MPCFO-E/PEO-based and MPCFS-E/PEO-based DSSCs exhibited lower electrochemical resistances, superior photovoltaic (PV) properties, and improved PV stabilities relative to those of the corresponding PEO-based DSSC. Among the studied systems, the DSSC based on the MPCFO-E (0.5 wt.%)/PEO blend electrolyte exhibited the best PV performance, with a short current density of 4.97 mA cm−2 and a photoenergy conversion efficiency of 1.17%.