Microphase-separated Morphology Research Articles

High‐Efficiency Organic Solar Cells Enabled by Non‐Fullerene Acceptors with Benzimidazole as the Central Core

AbstractElectron‐deficient central core plays a crucial role in the construction of efficient Y‐series non‐fullerene acceptors (NFAs). Here, fused‐ring benzimidazole (BIm) served as a central core for the first time to yield a new NFA named MZ‐1 and its structural analogue named MZ‐2, which is obtained by replacing the methyl group on the 2C position of BIm in MZ‐1 with trifluoromethyl group. Compared with MZ‐1, MZ‐2 shows obviously blue‐shifted absorption and lowers the highest occupied molecular orbital (HOMO) energy level that is more matched to that of polymer donor PM6. Benefiting from the more efficient charge transport and favorable microphase separation morphology of the active layer, the acceptor MZ‐2‐based device affords an excellent power conversion efficiency (PCE) of 17.31% along with a high open‐circuit voltage (Voc) of 0.903 V, a short‐circuit current density (Jsc) of 26.32 mA cm−2 and a fill factor (FF) of 72.83%, which is remarkably superior to that of MZ‐1‐based devices with PCE of 10.70%. This study offers valuable insight into the design of acceptors to enrich Y series NFAs for high‐performance organic solar cells (OSCs).

Nanostructures, Linear Rheological Responses, and Tunable Mechanical Properties of Microphase-Separated Cellulose-graft-Diblock Bottlebrush Copolymer Elastomers.

A series of cellulose-graft-diblock bottlebrush copolymer elastomers (cellulose-graft-poly(n-butyl acrylate)-block-poly(methyl methacrylate) (Cell-g-PBA-b-PMMA)) with short side chains were synthesized via successive atom transfer radical polymerization (ATRP) to study the influence of varying compositions and lengths of the graft diblock side chains on microphase morphologies and properties. The microphase-separated morphologies from misaligned spheres to cylinders were observed by atomic force microscopy (AFM) and small-angle X-ray scattering (SAXS) measurements. These bottlebrush copolymer elastomers possessed thermal stability and enhanced mechanical properties because the PMMA outer block could self-assemble into hard microdomains, which served as physical cross-links. The viscoelastic responses of these bottlebrush copolymers within the linear viscoelastic (LVE) regime were carried out by the oscillatory shear rheology. The time-temperature superposition (tTs) principle was applied to construct the master curves of the dynamic moduli, and the sequential relaxation of dense bottlebrush copolymers with different PMMA hard outer block lengths was analyzed. The rheological behaviors in this work could be utilized to build up the connection of microstructures and properties for the application of these bottlebrush copolymers as high-performance thermoplastic elastomers.

Effects of molecular weight of polyethylene glycol on the moisture-absorption capacity and morphology of the channeling structure in desiccant composite

Moisture removal inside the packaging of food and pharmaceutical products prevents their deterioration during storage. Therefore, the preparation of desiccants derived from moisture-absorbing materials is important. Herein, desiccant composites with channeling morphologies in the polypropylene (PP) matrix are prepared using polyethylene glycol (PEG) with different molecular weights (Mw) and molecular sieves (MS). The effects of the Mw on the formation, morphology, and stability of the channeling structure are investigated. All composites exhibit microphase separation morphology caused by the channeling structure. Accordingly, the PEG with an Mw of 8000 allows uniform microphase separation in the composite matrix owing to the higher chemical compatibility with MS in the formation of the channeling structure, thus inducing significant moisture absorption. Therefore, these composites can be used to introduce novel desiccant packaging in the food and pharmaceutical industries.

Semi-crystalline sulfonated poly(ether ketone) proton exchange membranes: The trade-off of facile synthesis and performance

Improving the performance of proton exchange membranes (PEMs) through the synthesis of sulfonated polymers with elaborate molecular structures has received extensive approval. However, the tedious synthetic process and consequently high costs restrain their possible substitution for Nafion, a classic PEM material. Herein, a series of semi-crystalline sulfonated poly(ether ketone)s with fluorene-based units were prepared via direct copolymerization of commercially available monomers and followed post-sulfonation, namely SPEK-FD-x, where × represents the molar ratio of the fluorene-containing monomer to the employed bisphenol monomers. The entire synthetic pathway was facile without involving hardly accessible materials. Subsequently, various properties of SPEK-FD-x membranes were investigated and further compared with Nafion 117. Due to the formation of the well-defined hydrophilic-hydrophobic microphase separation morphology and the reinforcement of the PEK crystalline regions, the SPEK-FD-x membranes exhibited outstanding proton conductivity, resistance for methanol permeation, as well as dimensional, thermal, oxidative, and mechanical stability. Among them, the overall behavior of the SPEK-FD-25 membrane was comparable to or even greater than that of Nafion 117, most importantly, it also performed decently in both H2/air fuel cells and direct methanol fuel cells. Therefore, with the straightforward synthesis and superior performance, the SPEK-FD-x membranes may serve as a promising alternative to Nafion.

Block copolymer interfaces investigated by means of NMR, atomic force microscopy and dielectric spectroscopy

Self-assembly of block copolymers (BC) is a key feature for bottom-up patterning that is applied in the fabrication of templates for nanostructured membranes, photonic nanodevices, or solar cells. The wide range of possible BC applications is because the dissimilar blocks can be appropriately selected to form distinct domains with controllable dimensions and functionalities. An important representative of these materials is polystyrene-b-poly(ethylene oxide) (PS-b-PEO) diblock copolymer. This copolymer is of considerable academic interest and therefore it is examined by a plethora of experimental techniques to elucidate its structure and molecular dynamics. Particularly worth investigating is the interphase, consisting of polymer chains located at the interface of crystallite-amorphous and inter-domain regions, which codetermines the properties of such a system. It is shown that below the melting point of the PEO, the majority of the amorphous PEO are occupying interfacial sites and are represented by the rigid amorphous fraction (RAF) which can be monitored by dielectric and nuclear magnetic resonance spectroscopies. Moreover, two independent NMR spin-diffusion experiments reveal the asymmetrical nature of PS-PEO interface indicating a significant fraction of the PEO phase under the influence of stiff, adjacent polystyrene. An analysis of complementary thermal calorimetry and X-ray scattering data confirms the presence of microphase-separated morphology as well as the semicrystalline nature of PEO component. Lamelar domain architecture was confirmed by atomic force microscopy data acquired in the case of thin copolymer film.

“Thiol-ene” crosslinked polybenzimidazoles anion exchange membrane with enhanced performance and durability

To address the “trade-off” between conductivity and stability of anion exchange membranes (AEMs), we developed a series of crosslinked AEMs by using polybenzimidazole with norbornene (cPBI-Nb) as backbone and the crosslinked structure was fabricated by adopting click chemical between thiol and vinyl-group. Meanwhile, the hydrophilic properties of the dithiol cross-linker were regulated to explore the effect for micro-phase separation morphology and hydroxide ion conductivity. As result, the AEMs with hydrophilic crosslinked structure (PcPBI-Nb-C2) not only had apparent micro-phase separation morphology and high OH− conductivity of 105.54 mS/cm at 80 °C, but also exhibited improved mechanical properties, dimensional stability (swelling ratio < 15%) and chemical stability (90.22 % mass maintaining in Fenton’s reagent at 80 °C for 24 h, 78.30 % conductivity keeping in 2 M NaOH at 80 °C for 2016 h). In addition, the anion exchange membranes water electrolysis (AEMWEs) using PcPBI-Nb-C2 as AEMs achieved the current density of 368 mA/cm2 at 2.1 V and the durability over 500 min operated at 150 mA/cm2 under 60 °C. Therefore, this work paves the way for constructing AEMs by introduction of norbornene into polybenzimidazole and formation of hydrophilic crosslinked structure based on “thiol-ene”.

Synthesis and characterization of UV curable biocompatible hydrophilic copolymers containing siloxane units

Tissues are highly three-dimensional structure complexes composed of different cell types and their interactions. One of the main challenges in tissue engineering is the inability to produce large, highly perfused scaffolds in which cells can grow at a high cell density and viability. Poly(dimethyl siloxane) (PDMS) is used as a flexible, biocompatible cell culture substrate with tunable mechanical properties. However, its fragility and hydrophobicity still pose a challenge. Here, we present a new strategy for the three-step one-pot synthesis of novel biocompatible hydrophilic copolymers containing siloxane units. In the first step, free radical copolymerization of acrylic acid (AA), butyl methacrylate (BMA), and 2-hydroxyethyl methacrylate (HEMA) was carried out in dioxane (DO) solution in the presence of 2,2′-azodiisobutyronitrile (AIBN). In the second step, the copolymers were modified with diepoxypropoxypropyl-terminated polydimethylsiloxane (DE-PDMS), and in the third step, the copolymers were additionally modified with glycidyl methacrylate (GMA). The modified copolymers were characterized by FTIR, NMR spectroscopy and elemental analysis. Films of modified copolymers were prepared by UV curing. SEM studies revealed microphase separated morphology with distribution of PDMS domains. The mechanical properties of the films depended on the amount of incorporated silicone modifier. The films were more hydrophilic than PDMS films. All novel copolymers showed high biocompatibility.

Installation of the adamantyl group in polystyrene-block-poly(methyl methacrylate) via Friedel–Crafts alkylation to modulate the microphase-separated morphology and dimensions

We present the polystyrene block post-polymerization modification of PS-b-PMMA through Friedel–Crafts alkylation with adamantanols to modulate its microphase-separated morphology and dimensions.

Leveraging peptide-cellulose interactions to tailor the hierarchy and mechanics of peptide-polymer hybrids.

Inspired by spider silk's hierarchical diversity, we leveraged peptide motifs with the capability to tune structural arrangement for controlling the mechanical properties of a conventional polymer framework. The addition of nanofiller with hydrogen bonding sites was used as another pathway towards hierarchical tuning via matrix-filler interactions. Specifically, peptide-polyurea hybrids (PPUs) were combined with cellulose nanocrystals (CNCs) to develop mechanically-tunable nanocomposites via tailored matrix-filler interactions (or peptide-cellulose interactions). In this material platform, we explored the effect of these matrix-filler interactions on the secondary structure, hierarchical ordering, and mechanical properties of the peptide hybrid nanocomposites. Interactions between the peptide matrix and CNCs occur in all of the PPU/CNC nanocomposites, preventing α-helical ordering, but promoting inter-molecular hydrogen bonded β-sheet formation. Depending on peptide and CNC content, the Young's modulus varies from 10 to 150 MPa. Unlike conventional cellulose-reinforced polymer nanocomposites, the mechanical properties of these composite materials are dictated by a balance of CNC reinforcement, peptidic ordering, and microphase-separated morphology. This research highlights that leveraging peptide-cellulose interactions is a strategy to create materials with targeted mechanical properties for a specific application using a limited selection of building blocks.

Hydrogen Bonding-Induced Crystal Orientation Changes in Confined Microdomains Constructed by Block Copolymer Blends

This study examined crystal orientation confined within a lamellar microdomain morphology formed by the blends of polystyrene-block-poly(ethylene oxide) (PS-b-PEO) and polystyrene-block-poly(acrylic acid) (PS-b-PAA) through wide-angle X-ray diffraction. The hydrogen-bonding interaction between PEO and PAA molecules enabled block copolymers to co-organize into a microphase-separated morphology without inducing macrophase separation, but it hampered PEO crystallization. PEO crystallization that occurred at −20 °C resulted in the nucleation mechanism to be dominant, thus leading to the formation of small crystals. Small crystals allowed them to be free from spatial confinement, and they tended to be oriented with their c-axis parallel to the microdomain interface. By contrast, when PEO was crystallized at 40 °C, the high temperature facilitated PEO crystals to exhibit large crystallite sizes, which aligned perpendicularly to the microdomain interface. An increase in the PS-b-PAA concentration considerably reduced the crystallizability of PEO. The presence of a low amount of crystals and additional lateral confinement formed by hydrogen-bonded PEO/PAA reduced the degree of orientation regardless of the crystallization temperature.

Development of shape memory polyurethane/SBS compositely modified asphalt and synergistic modification mechanism

To develop new shape memory polyurethane/styrene butadiene styrene (SMPU/SBS) compositely modified asphalt (PSA) with obvious shape memory property, and to reveal the synergistic modification mechanism and shape memory effect, the optimum blending ratio of different components in PSA and its preparation method were determined by orthogonal test and range analysis. Then the differential scanning calorimetry (DSC), shape memory property test, wide-angle X-ray diffraction (WXRD), Fourier transform infrared spectrometer (FTIR) and atomic force microscope (AFM) were used to study the phase transition temperature, shape memory property, chemical component compatibility, microphase separation and microscopic morphology of PSA samples. The results show that the developed PSA has better anti-deformation and anti-cracking properties, and the modifiers are compatible with matrix asphalt. The phase transition temperature of PSA is accommodative with the working temperature of asphalt pavement. Also, the shape recovery of SMPU can be stimulated by natural environment temperature, which improves the self-healing efficiency of damage or crack in PSA. The obvious microphase separation occurs between soft and hard segments in SMPU, so the shape memory property of PSA is better than that of SBS modified asphalt (SA). SMPU chemically modifies asphalt, which improves the orientation and arrangement of hard segments in SMPU, as well as the agglomeration, crystallization and precipitation of hard segments occur during the cooling. All these lead to the microphase separation between soft and hard segments, improving the shape memory properties of PSA. After the composite modification, the crystal size and spacing of hard segments in SMPU become smaller, as well as a continuous, stable and compact spatial network structure is formed in PSA. These increase the anti-deformation and shape recovery properties of PSA, as well as are conducive to improve the self-healing efficiency of damage or crack in PSA. This study reveals the synergistic modification mechanism of SMPU and SBS on asphalt, as well as the shape memory effect of PSA.

Morphological Effect of Side Chain Length in Sulfonated Poly(arylene ether sulfone)s Polymer Electrolyte Membranes via Molecular Dynamics Simulation.

With the recognition of the multiple advantages of sulfonated hydrocarbon-based polymers that possess high chemical and mechanical stability with significant low cost, we employed molecular dynamics simulation to explore the morphological effects of side chain length in sulfonated polystyrene grafted poly(arylene ether sulfone)s (SPAES) proton exchange membranes. The calculated diffusion coefficients of hydronium ions (H3O+) are in range of 0.61-1.15 × 10-7 cm2/s, smaller than that of water molecules, due to the electrical attraction between the oppositely charged sulfonate group and H3O+. The investigation into the radial distribution functions suggests that phase segregation in the SPAES membrane is more probable with longer side chains. As the hydration level of the membranes in this study is relatively low (λ = 3), longer side chains correspond to more water molecules in the amorphous cell, which provides better solvent effects for the distribution of sulfonated side chains. The coordination number of water molecules and hydronium ions around the sulfonate group increases from 1.67 to 2.40 and from 2.45 to 5.66, respectively, with the increase in the side chain length. A significant proportion of the hydronium ions appear to be in bridging configurations coordinated by multiple sulfonate groups. The microscopic conformation of the SPAES membrane is basically unaffected by temperature during the evaluated temperature range. Thus, it can be revealed that the side chain length plays a key role in the configuration of the polymer chain and would contribute to the formation of the microphase separation morphology, which profits proton transport in the hydrophilic domains.

Hydrogen bonding induced microphase and macrophase separations in binary block copolymer blends

This study investigated the macrophase and microphase transitions of blends comprising polystyrene-block-poly(ethylene oxide) (PS-b-PEO) and polystyrene-block-poly(acrylic acid) (PS-b-PAA). PEO and PAA molecules formed hydrogen bonds that enabled the two block copolymers to organize into a single microphase-separated morphology composed of two PS block chains in a common PS microdomain and PEO and PAA block chains in a coexisting PEO/PAA microdomain. Increasing temperature weakened the hydrogen-bonding interaction through the formation of PAA monomers and anhydride, causing the blends to macrophase separate into PS-b-PEO-rich and PS-b-PAA-rich phases. Further increasing the temperature weakened the repulsive interactions between both the PS and PEO segments and the PS and PAA segments, inducing order-to-disorder transitions in the PS-b-PEO-rich and PS-b-PAA-rich phases. However, the increasing repulsive interaction between the PEO and PAA segments with increasing temperature prevented the blends from forming an isotropic phase. The unique phase transformation of each block copolymer in the blend with an upper critical ordering transition (UCOT)-type interaction parameter, which caused the formation of a lower-critical-solution-temperature-type phase diagram, was attributed to the hydrogen-bonding interaction between PEO and PAA, which outweighed the UCOT behaviors of PS-b-PEO and PS-b-PAA and reversed the phase behaviors of their blends.

Pyrrolidinium-Based Hyperbranched Anion Exchange Membranes with Controllable Microphase Separated Morphology for Alkaline Fuel Cells.

It is well acknowledged that the microphase-separated morphology of anion exchange membranes (AEMs) is of vital importance for membrane properties utilized in alkaline fuel cells. Herein, a rigid macromolecule poly(methyldiallylamine) (PMDA) is incorporated to regulate the microphase morphology of hyperbranched AEMs. As expected, the hyperbranched poly(vinylbenzyl chloride) (HB-PVBC) is guided to distribute along PMDA chains, and longer PMDA cha leads to a more distinct microphase morphology with interconnected ionic channels. Consequently, high chloride conductivity of 10.49 mS cm-1 at 30 °C and suppressed water swelling ratio lower than 30% at 80 °C are obtained. Furthermore, the β-H of pyrrolidinium cations in the non-antiperiplanar position increases the energy barrier of β-H elimination, leading to conformationally disfavored Hofmann elimination and increased alkaline stability. This strategy is anticipated to provide a feasible way for preparing hyperbranched AEMs with clear microphase morphology and good overall properties for alkaline fuel cells.

Mechanically robust and highly conductive semi-interpenetrating network anion exchange membranes for fuel cell applications

A series of highly transparent semi-interpenetrating polymer network anion exchange membranes (SIPN AEMs) composed of a flexible and cation cross-linked polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (cQSEBS) component, and a rigid, highly-charged quaternized poly(2,6-dimethyl phenylene oxide) (QPPO) component are prepared. Flexible and rigid polymer backbones endow SIPN AEMs with excellent flexibility and mechanical strength. High charge content and well defined hydrophilic/hydrophobic phase separation patterns ensure SIPN AEMs with improved ionic conductivity. Alkali-resistant SEBS, enhanced dimensional stability and ordered microphase separation morphology contribute to the good chemical stability of SIPN-AEMs. Among these AEMs, SIPN-cQSEBS/QPPO-10 with an IEC of 1.93 mmol g−1 achieves a better trade-off between tensile strength (19.36 MPa at 25 °C in wet state), flexibility (58.43% at 25 °C in wet state) and OH− conductivity (103.1 mS cm−1 at 80 °C). Besides, SIPN-cQSEBS/QPPO-10 shows low swelling degree (15.4% at 80 °C) and high chemical stability (95.9%, 88.7%, 82.7% and 88.5% retention in weight, OH− conductivity, tensile strength and elongation at break, respectively, after immersing in 1 M NaOH at 80 °C for 30 days). Importantly, a fuel cell peak power density of 1.174 W cm−2 is obtained at 80 °C by using SIPN-cQSEBS/QPPO-10 as the separator.

Effect of bio-based polyols and chain extender on the microphase separation structure, mechanical properties and morphology of rigid polyurethane foams

The preparation of polyurethane foams from bio-based polyols was a preferable alternative to save fossil resources, and the investigation of the microphase separation structure of foams can effectively guide their application. In this work, rigid polyurethane (PU) foams from three bio-based polyols and different content of chain extender of 1,4-butanediol were prepared. Microphase separation behavior and thermodynamic properties of the foams were analyzed by ATR-FTIR, SEM, TG, DSC and DMA. The hydrogen bond content increases and the microphase separation tendency is suppressed with the addition of bio-based polyols. The TG analysis reveals that the thermal loss of bio-based foams is earlier than that of petroleum-based foams at the initial stage. The hydrogen bond content of bio-based rigid PU foam derived from corn stalks increases by 6.03 % relative to petroleum-based foam, and the compression strength reaches 160.18 KPa. Furthermore, with the addition of 1,4-butanediol (5 wt%), the compression strength of bio-based rigid PU foam derived from corn stalks rises to 325.05 KPa, while the proportion of ordered hydrogen bonds is considerably higher than that of the original foam, demonstrating the increase in the degree of microphase separation.

Construction of gas permeable channel in poly(l-lactic acid) membrane and its control of the micro atmosphere in okra packaging

An atmosphere within a package affects the metabolic process of food and the microbial growth of fresh products and has a vital role in preserving food. It depends on the membrane's specific gas permeability and selectivity to generate a desirable atmosphere for storage. In this study, triblock poly(l-lactic acid‑d-ɛ-caprolactone) (PLDC) copolymers and three-arm poly(l-lactic acid-g-ɛ-caprolactone) (PLGC) star copolymers were synthesized, in which a microphase-separated morphology of sea-island structure was established in PLGC membrane as a gas “fast permeation channel” for regulating CO2 and O2 permeability and CO2/O2 selectivity. AFM observation revealed different well-defined micro phase-separated structures of PLGC with size ranges of 200– 300 nm. Comparing PLGC membrane with PLLA, CO2 and O2 transmission rates increased by 416.9 % and 132.7 %, while H2O transport rates increased by 245.6 %. Mechanical testing shows that the PLGC membrane exhibits 40.8-fold elongation at break compared to PLLA, showing excellent flexibility. Moreover, okra's equilibrium-modified atmosphere packaging was designed based on a theoretically derived model. Preservation results suggested that the PLGC packaging membrane could generate an ideal high 8.7– 9.2 % CO2 and low 2.3– 2.7 % O2 atmosphere for okra preservation, delaying the discoloring and rotting of okra.

Adamantane-based block poly(arylene ether sulfone)s as anion exchange membranes

Current anion exchange membranes (AEMs) for fuel cells suffer from low ionic conductivity and poor mechanical property. Herein, we introduce adamantane groups onto the block poly(arylene ether sulfone)s backbone to form the selected comb-shaped structure. The structure-property relationships of the AEMs are investigated by varying the ratio of the hydrophobic to hydrophilic segments. The bulk rigid adamantane group can restrain the swelling of the AEMs thus enhancing the mechanical properties and expand the spacing between the hydrophilic/hydrophobic segments of the polymer chains to promote the formation of microphase separation morphology. Consequently, as characterized by atomic force microscope (AFM) and transmission electron microscopy (TEM), the resulting membranes show well-defined microphase separation between the hydrophilic/hydrophobic segments, resulting in high ionic conductivity range from 27.4 to 90.2 mS cm −1 over a temperature range of 30–80 °C. At the same time, the membranes present ultralow swelling ratio with the levels from 1.6% to 6.1% at 30 °C and from 6.8% to 12.7% at 80 °C, respectively, and thus excellent mechanical properties with the tensile strength as high as 11.52 MPa and elongation at break of 29.28%. The excellent comprehensive properties grant the prepared AEMs bright future for fuel cells. • A series of adamantane-based block poly(arylene ether sulfone)s AEMs was prepared. • Influence of hydrophobic chain segments on AEMs' properties and morphology was studied. • The AEMs showed well-defined microphase separation between the hydrophilic/hydrophobic segments. • The AEMs showed high hydroxide conductivity in the range of 27.4–90.2 mS cm −1 .

Double Gyroid Morphologies in Precise Ion-Containing Multiblock Copolymers Synthesized via Step-Growth Polymerization.

The double gyroid structure was first reported in diblock copolymers about 30 years ago, and the complexity of this morphology relative to the other ordered morphologies in block copolymers continues to fascinate the soft matter community. The double gyroid microphase-separated morphology has co-continuous domains of both species, and the minority phase is subdivided into two interpenetrating network structures. In addition to diblock copolymers, this structure has been reported in similar systems including diblock copolymers blended with one or two homopolymers and ABA-type triblock copolymers. Given the narrow composition region over which the double gyroid structure is typically observed (∼3 vol %), anionic polymerization has dominated the synthesis of block copolymers to control their composition and molecular weight. This perspective will highlight recent studies that (1) employ an alternative polymerization method to make block copolymers and (2) report double gyroid structures with lattice parameters below 10 nm. Specifically, step-growth polymerization linked precise polyethylene blocks and short sulfonate-containing blocks to form strictly alternating multiblock copolymers, and these copolymers produce the double gyroid structure over a dramatically wider composition range (>14 vol %). These new (AB)n multiblock copolymers self-assemble into the double gyroid structure by having exceptional control over the polymer architecture and large interaction parameters between the blocks. This perspective proposes criteria for a broader and synthetically more accessible range of polymers that self-assemble into double gyroids and other ordered structures, so that these remarkable structures can be employed to solve a variety of technological challenges.

Mechanically flexible bulky imidazolium-based anion exchange membranes by grafting PEG pendants for alkaline fuel cells

Imidazoliums with bulky substitutes are promising alternative cations for anion exchange membranes due to their superior stability under alkaline conditions. However, bulky imidazolium-based AEMs suffer from low conductivity as well as poor film-forming ability, and thus unfavorable fuel cell performance. Herein, we presented a strategy to graft hydrophilic and flexible polyethylene glycol (PEG) chains on the imidazoliums to prepare imidazolium-type AEMs. The resulting AEMs showed excellent film-forming ability with reasonable tensile strengths of 18.7 MPã31.8 MPa and high elongation at break of 21.2%–133.3%. Owing to the well-developed microphase-separated morphology and increased water uptake, the AEMs with a low ion exchange capacity of 0.95 meq./g displayed the hydroxide conductivity of 32.3 mS/cm at 20 °C. After immersion in 1 M NaOH at 80 °C for 1248 h, the initial conductivity was maintained by 37.1%–47.9%, and the degradation mechanism was explored by model imidazolium cations investigation. In addition, the Im-PEG-PPO-70 membrane having the highest conductivity was fabricated into membrane electrode assembly, exhibiting a peak power density of 179 mW/cm2 at 60 °C in a single H2/O2 alkaline fuel cell. A short-term life test on this MEA under 200 mA/cm2 showed a performance decay rate of 2.3 mV/h over 100 h of operation.