Conducting Polymer Blends Research Articles

A study on blend polymer electrolyte based on poly(vinyl alcohol)-poly (acrylonitrile) with magnesium nitrate for magnesium battery

Studies on magnesium ion conducting blend polymer electrolyte (BPE) at room temperature are reported. BPE films of optimized 92.5PVA:7.5PAN ratio in view of its maximum conductivity with various concentrations of magnesium salt—Mg(NO3)2—of different molar mass percentages (0.1, 0.2, 0.3, and 0.4 m.m.%) have been prepared using solution-casting technique with dimethylformamide (DMF) as solvent. The promising characteristic features of these films have been studied. Possible conformational changes in the polymer host 92.5PVA:7.5PAN due to Mg(NO3)2 entrapment have been investigated by FTIR and XRD analysis. The composition 92.5PVA:7.5PAN:0.3 m.m.% Mg(NO3)2 offers maximum electrical conductivity of 1.71 × 10−3 S/cm at room temperature. The σ values follow the Arrhenius equation, and the activation energy for the optimized composition is 0.36 eV. The variations in glass transition temperature have been found using differential scanning calorimeter. Mg2+ ion conduction in the BPE film is confirmed using transference number measurement and cyclic voltammetry. The transport number of the Mg2+ ion is 0.30. Using linear sweep voltammetry, the electrochemical stability window for the highest BPE has been measured. Primary magnesium battery has been constructed using the maximum conducting membrane, and its output characteristics have been studied.

Studies on Conducting Polymer Blends: Synthesis and Characterizations of PVA/PVP Doped with CaCl₂.

Calcium ion conducting polymer blend electrolyte films based on PVA/PVP complexed with CaCl2 have been prepared by solution casting technique. The structural changes of the polymer blends have been studied by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. XRD and FT-IR studies confirmed the complex formation of polymer blends. Electrical conductivity was calculated with impedance analyzer within the frequency range 42 Hz-1 MHz and in the temperature range 303 K-340 K. The higher electrical conductivity value of 1.704 × 10-4 Scm-1 was observed for 50PVA:50PVP:15 wt% CaCl2 concentration at room temperature. The magnitude of electrical conductivity was increased with the increase in the salt concentration as well as temperature. The electrical permittivity of the polymer films have been studied for various temperatures.

Single Ion Conducting Blend Polymer Electrolytes Based on LiPAAOB and PPEGMA

Single-ion polymer electrolytes are expected to play an important role in the development of next-generation lithium batteries. The current work focuses on the designing of novel solid single-ion conducting inorganic polymer electrolytes based on lithium polyacrylic acid oxalate borate (LiPAAOB) and poly(ethyleneglycol) methacrylate (PEGMA). PEGMA is polymerized into PPEGMA via free radical polymerization and LiPAAOB is prepared from poly(acrylic acid), oxalic acid and boric acid. Blend polymer electrolytes were produced by mixing of LiPAAOB with PPEGMA at different weight fractions to enhance the single ion conductivity of the system. To exploit the flexible chemistry and increase segmental mobility of the blend electrolyte, the composition was changed up to 80% with respect to PPEGMA. FT-IR and differential scanning calorimeter technique verifies the interaction between the host and guest polymers. Thermogravimetry analysis verified that the thermal stability of the blends increased up to approximately 200 °C. Scanning electron microscopy images confirm the homogeneity of the blend electrolytes. Cyclic voltammetry studies showed that electrochemical stability electrochemical stability window is approximately 5 V versus Li/Li+. The effect of PPEGMA on to the Lithium ion conductivity was investigated using dielectric impedance analyzer. The maximum single ion conductivity was measured as 1.3 × 10−4 S/cm at 100 °C for the sample LiPAAOB-80PPEGMA. Clearly these results confirmed the positive effect to the increment in ionic conductivity of the blend electrolytes with the addition of PPEGMA.

Preparation and Characterization of Conductive Polymer Blends of Polypyrrole and Poly(ethylene oxide).

Conductive polymer blends of polypyrrole (PPy) and poly(ethylene oxide) (PEO) were obtained in the form of films and fibers, respectively by solvent casting and electrospinning. Different amounts of PPy were introduced in the blends in order to study the effect of the conductive polymer on the properties of the final material and in particular to elucidate the influence of the different morphology on conductivity. The structure and morphology of PPy/PEO blends were characterized by wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to understand the influence of different PPy content on thermal behavior and stability, electrospun fibrous mats were examined by scanning electron microscopy (SEM). The conductivity of the films and fibrous mats was measured and correlation with morphology was highlighted.

Piezoresistive response of extruded polyaniline/(styrene-butadiene-styrene) polymer blends for force and deformation sensors

Smart materials for sensor applications are increasingly being used in a wide variety of applications ranging from engineering to medical devices. This work reports on piezoresistive sensors based on conductive polyaniline and thermoplastic elastomer processed by conventional polymer extrusion. The material presents excellent processability and piezoresistive performance offering an alternative to traditional composites with conductive nanofillers for sensor applications.The polyaniline/styrene-butadiene-styrene (PANI/SBS) conductive polymer blends present good mechanical properties, high electrical conductivity and piezoresistive response. The maximum strain reaches ≈60% for 30 weight percentage (wt%) PANI content and the electrical conductivity is σ≈0.1S/m for blends with 40wt% PANI content. Further, the sample with 40wt% PANI content shows a piezoresistive gauge factor GF≈1 for deformation measurements between 0.1 and 3mm in bending cycles.

Kinetic Control of Graphene Localization in Co-continuous Polymer Blends via Melt Compounding.

Selective localization of graphene in co-continuous polymer blends is an attractive method for preparing conductive polymer composites. Localization of graphene at the interface between the two polymer phases produces good conductivity at ultra-low concentrations. Although graphene localization is ultimately dependent on thermodynamic factors such as the surface energy of graphene and the two polymer components, kinetics also strongly affects the migration and localization of graphene in polymer blends during melt compounding. However, few studies have systemically investigated the important role of kinetics on graphene localization. Here, we introduced graphene nanoplatelets (GNPs) in polylactic acid (PLA)/polystyrene (PS) co-continuous polymer blends. Although GNPs in thermal equilibrium prefer the PS phase, we were able to kinetically trap GNPs at the interface of polymer blends via control of melt-compounding sequences, mixing times and shear rates. Utilizing morphological, rheological, and electrical measurements, we verified graphene localization and the suppression of coarsening in co-continuous polymer blends during annealing. When GNPs were premixed with the thermodynamically less-favorable PLA phase before mixing with the PS phase, GNPs can be kinetically trapped at the interface during melt compounding. Moreover, we show that a shorter melt-compounding time gives rise to a higher GNP interfacial coverage and a more effective morphology stabilization effect. Blends with as low as 0.5 wt % GNPs with only 30 s of melt compounding have a room-temperature conductivity of ∼10-6 S/cm, which is larger than blends with longer melt-compounding times and potentially useful for antistatic materials. The in-depth study on the kinetics of graphene localization in our work provides a general guideline for the kinetic control of the localization of platelike nanofillers in polymer blends. Our study also demonstrates a facile method for manufacturing conductive polymer blends with low percolation thresholds.

Construction of interconnected micropores in poly(arylene ether) based single ion conducting blend polymer membranes via vapor-induced phase separation

We report the construction of interconnected micropores in a poly(arylene ether) based single ion conducting blend polymer electrolyte by tuning phase separation. Bis(4-fluorine benzene sulfonyl)imide is copolymerized with bis(4-hydroxy benzene sulfonyl)imide and bisphenol A separately to form two types of AB alternating block copolymers, i.e., lithiated poly(bis(benzene sulfonyl)imide)ether (LiPBIE) and lithiated poly(bisphenol A-alt-bis(4-fluorine benzene sulfonyl)imide)ether (LiPAFE). The former is immiscible with poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and the latter is well entangled with the binder upon introducing the bisphenol group. The results reveal that the LiPBIE blend film exhibits an interconnected microporous structure while the LiPAFE blend film does not. Even if the ion exchange capacity (IEC) of the LiPAFE blend film is raised to the level of the LiPBIE blend film by reducing the proportion of PVDF-HFP, the film is porous only on the surface but remains dense in its bulk. The comparative experiments confirm that the disparity of polarity and solubility between the ionomers and the binder is largely responsible for the phase separation. The microporous single ion conducting gel polymer electrolyte offers an ionic conductivity of 0.52 mS cm−1 at 25°C and its membrane displays the capability of dendrite suppression. A battery incorporating the electrolyte film exhibits excellent rate performance and electrochemical stability.

Lightning strike resistance of an electrically conductive CFRP with a CSA-doped PANI/epoxy matrix

An analysis of a structural damage extent of a developed electrically conductive CFRP composite exposed to the high-current electrical discharges simulating lightning strikes was conducted in order to evaluate its ability of carrying on lightning electrical current and its damage resistance during lightning events. The composite was fully fabricated from organic compounds, i.e. electrically conductive polymer blend of polyaniline (PANI) doped with camphorsulfonic acid (CSA) and epoxy resin, and carbon fabric used both as a mechanical reinforcement as well as supporting electrical conductor for ensuring adequate electrical conductivity and mechanical properties. An investigation of lightning strike resistance was performed during high-voltage and high-current mode tests. For preliminary evaluation the resulting damage was examined using visual inspection. Furthermore, the ultrasonic testing and X-ray computed tomography were applied for evaluation of degradation mechanisms occurring during a typical lightning strike event. The obtained results show that the developed composite is characterized by good electrical conductivity and mechanical properties and may successfully resist high-current impulse discharges typical for lightning strike events. Therefore, the developed composite can be considered asa potential candidate for a lightning strike protection material in aircraft industry and other applications.

Using Femtosecond Laser Irradiation to Enhance the Vertical Electrical Properties and Tailor the Morphology of a Conducting Polymer Blend Film.

We report femtosecond infrared laser-induced selective tailoring of carrier transport as well as surface morphology on a conducting polymer blend thin film. Maximal 2.4 times enhancement on vertical current transport in poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester, was achieved by this irradiation. The laser irradiation induced a photo expansion without deteriorating its molecular structure and the film morphology could be customized in the micron scale by adjusting the laser writing parameters. In the photoexpanded region, the face-on populations were about 2.2 times larger in comparison with the pristine region, which was a major contributor to the enhanced carrier transport.

Mg-ion conducting blend polymer electrolyte based on poly(vinyl alcohol)-poly (acrylonitrile) with magnesium perchlorate

Research on magnesium battery has gained momentum in recent years due to its high stability and hazardous free nature. For such batteries solid polymer electrolyte films have been prepared using blend polymer technique with the polymers polyvinyl alcohol (PVA) & polyacrylonitrile (PAN) (92.5PVA:7.5PAN) and Mg(ClO4)2 of different molar mass percentage (m.m.%) as 0.05%,0.1%,0.15%,0.2%,0.25% and 0.3% by solution casting technique using DMF as solvent. The XRD results confirms that the incorporation of magnesium salt (Mg(ClO4)2) which reduces the crystallinity of blend polymer (92.5PVA:7.5PAN). FTIR has been carried out to study the complex formation between the blend polymer and salt. AC impedance spectroscopy has been used to examine the ionic conductivity and dielectric behaviour of the blend polymer electrolyte (BPE). The maximum ionic conductivity of 2.96×10−4S/cm has been observed for the sample 92.5PVA:7.5PAN:0.25m.m.% Mg(ClO4)2 at room temperature for which the activation energy measured is minimum (0.21eV). Electrochemical studies show that highest conducting BPE has the highest electrochemical stability. Transference number measurement confirms that the conducting species are Mg2+ ion. Primary magnesium battery has been constructed with maximum conducting electrolyte system and its discharge characteristics have been studied.

Lithium ion-conducting polymer electrolytes based on PVA–PAN doped with lithium triflate

Blend polymer electrolytes with optimized composition (92.5 PVA:7.5 PAN) doped with lithium triflate (LiCF3SO3) have been prepared in different concentrations by solution casting technique, using DMF as solvent. The prepared electrolytes have been characterized by XRD, FTIR, DSC, AC impedance, and SEM techniques. The complex formation between the blend polymer and the salt has been confirmed by X-ray diffraction and FTIR analyses. Differential scanning calorimetry thermogram has shown a decrease in glass transition temperature with the addition of salt. It has been observed that the ionic conductivity of the doped blend polymer electrolyte increases as the salt concentration increases. The ionic conductivity has been found to be 4.0 × 10−5 S cm−1 for 92.5 PVA:7.5 PAN:50 M wt% LiCF3SO3 sample at room temperature. The temperature dependence of ionic conductivity has been studied with Arrhenius plot and the activation energies have been calculated. Primary lithium ion battery has been constructed with the configuration Zn + ZnSO4 7H2O/ 92.5 PVA:7.5 PAN:50 M wt% LiCF3SO3/ PbO2 + V2O5 using the maximum conducting blend polymer, and its discharge characteristics have been studied.

Magnesium ion conducting polyvinyl alcohol–polyvinyl pyrrolidone-based blend polymer electrolyte

Structural, thermal, electrical and electrochemical behaviour of polymer blend electrolytes comprising polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) as host polymers and Mg(ClO4)2 as dopant salt have been investigated. The changes in the structural properties on the incorporation of dopant in the blends were investigated by XRD and FTIR analyses. Thermal properties of pure PVA–PVP blend and their complexes were examined by DSC to measure how the thermal transitions of the prepared films were affected by different concentration of Mg(ClO4)2. The ionic conductivity and dielectric behaviour were explored using A.C. impedance spectroscopy. The trend of ionic conductivity increases almost proportionally to the content of magnesium salt and can be related to an increase of amorphous phase at high level of dopant salt. The electrochemical stability of the optimum conducting blend polymer electrolyte is found to be ∼3.5 V. The Mg2+ transference number for the sample with optimized conductivity was found to be 0.31.

Influence of carbon black and carbon nanotubes on the conductivity, morphology, and rheology of conductive ternary polymer blends

The influence of carbon black (CB) and multiwall carbon nanotubes (CNT) with different colloidal properties on the phase morphology, electrical properties, and rheological behavior in a polypropylene (PP)/poly(methyl methacrylate) (PMMA)/ethylene acrylic acid copolymer (EAA) ternary polymer blend was studied. A PP/PMMA/(EAA‐CNT) system was compared to two different PP/PMMA/(EAA‐CB) systems. The relationship between the phase morphology, electrical percolation threshold, and rheological behavior was analyzed. The critical percolation threshold for the ternary system was found to be around 0.5 vol% for the PP/PMMA/(EAA‐CB1) and 0.2 vol% for the PP/PMMA/(EAA‐CB2) and PP/PMMA/(EAA‐CNT), which were more than 8 times lower than for the single phase systems. The rheological threshold coincided with the electrical resistivity percolation threshold inversion point. It was proposed that beyond a critical loading of conductive filler particles in the minor EAA phase, especially for high aspect ratio fillers such as the CB2 and CNT, phase separation is slowed significantly due to the aggregation of particles into a network formation within the EAA phase causing a significant increase in phase viscosity. The results are consistent with the hypothesis that the kinetics of phase separation and resulting formation of a tri‐continuous morphology are dictated by the viscosity of the minor phase relative to the two major phases. POLYM. ENG. SCI., 57:1329–1339, 2017. © 2017 Society of Plastics Engineers

Experimental and numerical analysis of conductive ternary polymer blend composites

ABSTRACTExperimental and theoretical analysis of the phase morphology and electrical conductivity of a carbon black (CB)‐filled polypropylene /poly(methyl methacrylate) /ethylene acrylic acid copolymer ternary system were compared. The Cahn‐Hilliard theory was used to model and predict the phase morphology and electrical conductivity as a function of the constituents' characteristics of the ternary system. A method for generating statistically representative microstructures of a co‐continuous ternary polymer system and a numerical method for calculating the resultant electrical conductivity of these ternary polymer systems are presented. Excellent agreement between numerically calculated and experimentally measured results was observed. The developed analytical and numerical models were able to successfully predict the electrical percolation threshold with that of ternary polymer composites containing CB as a conductive medium with minimal experimental input. The combination of experimental and numerical results presented suggests the optimization of the conductive minor phase includes having a conductivity beyond the critical percolation threshold, is at least three orders of magnitude greater than either of the two nonconductive phases, and has a lower viscosity than the other two major phases in order to maximize the phase separation kinetics. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44749.

Study of PVAc-PMMA-LiCl polymer blend electrolyte and the effect of plasticizer ethylene carbonate and nanofiller titania on PVAc-PMMA-LiCl polymer blend electrolyte

Abstract lithium ion conducting polymer electrolyte is one of the essential components of modern rechargeable lithium batteries because of its good interfacial contact with electrodes and effective mechanical properties. A solid lithium ion conducting polymer blend electrolyte is prepared using poly (vinyl acetate) (PVAc) and poly (methyl methacrylate) (PMMA) polymers with different molecular weight percentages (wt%) of lithium chloride (LiCl) by the solution casting technique with tetrahydrofuran as a solvent. The polymer electrolytes were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), Thermogravimetry (TG), AC impedance spectroscopy and ionic transport measurements. XRD and FTIR studies confirm the amorphous nature of the polymer electrolyte and the complexation of salt with polymer. The thermal behavior of polymer electrolytes has been studied from DSC and TG. The highest conductivity obtained using AC impedance spectroscopy is 1.03×10−5 Scm−1 at 303 K for 70 wt%PVAc:30 wt%PMMA:0.8 wt% of LiCl polymer-salt complex. The plasticizer ethylene carbonate (EC) and nanofiller titania (TiO2) were added to the optimized high conducting blend polymer electrolyte. An enhancement in conductivity by one order of magnitude was observed for the plasticized 70 wt%PVAc-30 wt%PMMA-0.8 wt% LiCl polymer electrolyte at ambient temperature. The ionic conductivity value obtained using AC impedance spectroscopy for the plasticized 70 wt%PVAc-30 wt%PMMA-0.8 wt% LiCl polymer electrolyte was 1.03×10−4 Scm−1. The highest conductivity obtained for 70 wt%PVAc-30 wt%PMMA-0.8% LiCl-6 mg TiO2 was 4.45×10−4 Scm−1. Dielectric properties of polymer films are studied and discussed. The electrochemical stability of 1.69 V and 2.69 V was obtained for 70 wt%PVAc-30 wt%PMMA-0.8% LiCl and 70 wt%PVAc-30 wt%PMMA-0.8% LiCl-6 mg TiO2 polymer electrolytes, respectively, using linear sweep voltammetry. The value of Li+ ion transference number was estimated by the DC polarization method and was found to be 0.99 for the highest conducting 70 wt%PVAc-30 wt%PMMA-0.8 wt% LiCl-6 mg TiO2 nanocomposite polymer electrolyte.

Electrical Impedance Studies on Sodium Ion Conducting Composite Blend Polymer Electrolyte

Sodium ion conducting polymer blend thin films are of technologically interesting due to the tuned physical and electrical properties with wide variety of applications like sodium sulphur batteries, thermoelectric generators, electrochemical sensors, etc. sodium ion conducting composite blend polymer electrolyte films, based on poly vinyl alcohol (PVA) and poly(vinyl pyrrolidone) (PVP) complexed with NaCl were prepared by solution casting technique. The prepared films were characterized by various methods. The complexation of the salt with the polymer blend was identified by X-ray diffraction and Fourier transforms infrared spectroscopy. DSC was used to analyze the thermal behavior of the samples and the glass transition temperature is low for the highest conducting polymer material. The Frequency and temperature dependent of electrical conductivities of the films were studied using impedance analyzer in the frequency range of 1 Hz–1 MHz. The higher electrical conductivity of 50 PVA:50 PVP:15 wt% NaCl concentration has been found to be 1.747 × 10−3 Scm−1 at room temperature. The electrical permittivity of the polymer films have been studied for various temperatures.

Studies on conductivity and dielectric properties of PEO/PVP nanocomposite electrolytes for energy storage device applications

Investigations on Sodium-ion conducting polymer blend electrolyte systems based on PEO/ PVP complexed with NaIO 4 salt and TiO 2 nano fillers were presented in this report. The complexed polymer blend electrolytes were prepared in the form of dimensionally stable and free-standing films by conventional solution cast technique. Micro Raman and XRD studies confirmed the miscibility between PEO and PVP and the complexation of the salt with PEO/PVP polymer host. TEM measurements were carried out to evaluate size & distribution of the dispersed TiO 2 nanofillers. Complex impedance spectroscopy in the frequency 1 Hz – 1 MHz within the temperature range from room temperature to 343 K. Ionic conductivity of blend electrolytes increased with the increase of TiO 2 nanofillers concentration. Electrical conductivity and dielectric properties of NaIO 4 salt complexed blend PEO/ PVP/Na + electrolytes were analysed as a function of TiO 2 nanofillers concentration.

Impedance spectroscopy, ionic conductivity and dielectric studies of new Li+ ion conducting polymer blend electrolytes based on biodegradable polymers for solid state battery applications

New solid polymer blend electrolyte films based on biodegradable polymer blend comprising of polyvinyl alcohol (PVA) and poly (N-vinyl pyrrolidone) (PVP) doped with different wt% of lithium carbonate (Li2CO3) salt have been prepared by solution casting method. The resulting PVA/PVP/Li2CO3 polymer blend electrolyte films have been characterized by various analytical techniques such as FTIR, UV–vis, XRD, TGA, polarized optical microscopy and scanning electron microscopy. The FTIR and XRD analysis confirmed the complex formation between PVA/PVP blend and Li2CO3 salt. The ionic conductivity and the dielectric properties of PVA/PVP/Li2CO3 polymer blend electrolyte films were investigated using an impedance spectroscopy. It was observed that the ionic conductivity of PVA/PVP/Li2CO3 electrolyte system increases as a function of Li2CO3 concentration. The highest ionic conductivity was found to be 1.15 × 10−5 S cm−1 for polymer blend electrolyte with 20 wt% Li2CO3 content. On the other hand, the dielectric results revealed the non-Debye type of behaviour. The dielectric constant values indicate a strong dielectric dispersion in the studied frequency range which increases as the Li2CO3 content increases. The dielectric constant as high as 1200 (e = 1201.57, 50 Hz, 150 °C) and the dielectric loss well below 4 (tan δ = 3.94, 50 Hz, 150 °C) were obtained for polymer blend electrolytes with 25 wt% Li2CO3 salt. Thus, the results obtained in the present study suggest that the PVA/PVP/Li2CO3 polymer blend electrolyte system seems to be a promising candidate for solid state battery applications.

Development of environmental friendly castor oil-based waterborne polyurethane dispersions with polyaniline

This study describes the fabrication and characterization of castor oil-based waterborne polyurethane/polyaniline (COWPU/PAni) conducting polymer blend films. The COWPU synthesized from isophorone diisocyanate was reacted with castor oil to form prepolymers, which were chain extended by reacting it with N-methyldiethanolamine. Quaternization and self-emulsification including deionized water followed in COWPU dispersions. Also, COWPU/PAni hybrid dispersions were synthesized with 2, 4, and 6 wt% of PAni–dodecyl benzene sulfonic acid to make different conductive composites. The outcome of COWPU/PAni was characterized by Fourier transform infrared spectrometer, differential scanning calorimeter, thermogravimetric analysis, dynamic mechanical and thermal analyzer, and scanning electron microscopy analysis. According to Fourier transform infrared spectrometer analysis, hydrogen bonding appears between –NH of PAni and CO of COWPU. Meanwhile, incorporating PAni can improve the thermal stability of COWPU. The resulting COWPU/PAni conducting blend films can be used as antistatic and anticorrosive coating materials. Copyright © 2016 John Wiley & Sons, Ltd.

Selective Chain Alignment of Conducting Polymer Blend Films by an Ultrafast Laser

Tunable and selective areal polymer chain alignment method is developed for spin‐cast blend films of poly(3‐hexylthiophene)(P3HT):[6,6]‐phenyl‐C61‐butlyric methyl ester (PCBM) system by a femtosecond laser process. The chain alignment, phase separation, and molecular structure of the laser exposed P3HT:PCBM films are investigated by grazing incidence wide angle X‐ray scattering and micro‐Raman analysis. The alkyl chains of P3HT polymer become highly ordered along the polarization axis of the laser. Thus, the amount of desirable face‐on configuration for solar cell application is largely enhanced with a subsequent postannealing process. Vertically expanded morphology up to 200 nm on P3HT:PCBM films is also prompted by the laser irradiation without deteriorating intramolecular structure and changing chemical composition. Simultaneously, vertical phase separation of PCBM toward surface is induced at exposed region. image