Strong Ion-dipole Interactions Research Articles

Channel engineering strategy of precisely modified MOF/nanofiber composite separator for advanced aqueous zinc ion batteries

As the combination of metal-organic framework (MOF) materials with adjustable channels and flexible polymeric matrix, MOF/nanofiber composite separators enable the controllable ion transport behavior, which offers promising candidates for developing novel battery separators. In this study, series MOF functionalized electrospun polyacrylonitrile nanofiber separators were successfully developed via a precisely surface grafting strategy and then served as the separators for highly efficient aqueous zinc (Zn)-ion batteries (ZIBs). Moreover, channel engineering was developed by placing amino (MOF-N) and sulfonic acid groups (MOF-NS) on the channel surface of UIO-66, which then effectively promoted the ion transport progress. In particular, the resultant MOF-NS shows an excellent ionic conductivity (22.81 mS cm−1), improved Zn2+ transference number (0.78), and outstanding cyclic durability. These enhanced properties can be contributed by the effectively promoted dissociation of zinc salts and desolvation processes of hydrated Zn ions through strong ion-dipole interactions, as confirmed by the theoretical simulations. Our work demonstrates the great importance of channel engineering in modifying porous MOFs materials and the strong power of the precisely modified MOF/nanofiber separators in regulating ion transmission behavior and thus offers a promising separator candidate for high performance aqueous ZIBs.

Fabrication of all-starch-based hydrogels as eco-friendly water-absorbent resin: Structure and swelling behaviors

Water-absorbent resin has gained wide applications due to the capability in absorbing and retaining substantial amounts of water, while it's a challenge to fabricate a full biobased water-absorbent resin with excellent biodegradability and eco-friendliness. In this study, starch was sulfonated (SS) and crosslinked with epichlorohydrin to fabricate all-starch-based hydrogels (SSH) as water-absorbent resin with advantages of intrinsic biodegradability and low cost. The results confirmed that the hydrogen atoms of -OH groups in starch chains were partially replaced by -SO3− and the substitution degree (DS) of SS reached 0.008–0.344. By controlling DS and gelation process of SS, the swelling ratio (Qe) of SSH was improved in distilled water, reaching 244.47 g/g for samples prepared using SS with medium DS (SSMDSH). SSMDSH showed relatively loose network structure with low cross-linking density and large pore size. Meanwhile, -SO3− groups on SSMDSH chains facilitated strong ion-dipole interactions with water molecules, resulting in an increase in content of non-freezing bound water within hydrogels and thus improvement in water absorption capacity. Besides, SSH showed desired fertilizer absorption performance and complete biodegradability in α-amylase solution, which made it to be a promising candidate in agricultural fields as eco-friendly water-absorbent resin.

Cucurbit[7/8]uril assisted modulations in the photophysical properties of 4′,6-diamidino-2-phenylindole dye

The influence of two versatile macrocyclic hosts, cucurbit[7]uril (CB7) and cucurbit[8]uril (CB8), on the photophysical properties of a biologically important dicationic dye, 4′,6-diamidino-2-phenylindole (DAPI), has been investigated following different photophysical studies and quantum chemical calculations. Results indicate that while CB7 with having smaller cavity size forms only 1:1 dye-host inclusion complex with DAPI, the CB8 host with larger cavity size forms both 1:1 and 2:1 dye-to-host inclusion complexes with the dye. Quantum chemical studies indicate that while 1:1 complex is formed by inclusion of either the benzene or indole end of DAPI into a CBn cavity, the 2:1 complex in the DAPI-CB8 system is formed mainly by the inclusion of two benzene ends of two dye molecules into the host cavity, entering through opposite portals of the host. Estimated binding constant values for the dye-host complexes formed in these systems are found to be exceedingly high. Strong ion–dipole interaction of dicationic DAPI with polarizable CBn portals along with usual hydrophobic interaction arising from inclusion of the dye into the host cavity cooperatively provide the extremely high stability for the dye-host complexes formed in these systems. Overall, the results demonstrate that compatibility between the dye structure and the host cavity are mainly responsible for the differential bindings stoichiometries of the dye-host complexes formed in the studied DAPI-CBn systems. Further, these differences in the binding stoichiometries of the complexes are the main reason for the large differences observed in the modulated photophysical properties of the dye in the DAPI-CB7 and DAPI-CB8 systems. Since DAPI is an important fluorescence marker for several biomolecules, present results are having relevance to the applications of DAPI in various biophysical investigations.

Unveiling the underlying mechanism behind the greatly increased properties of Cu(I)-perovskites and their applications for durable WLED and multi-model encryption/decryption

Methods allowing all-inorganic perovskites to be performed on exceptional photophysical property with ultrastability are potentially important. Especially, the development of Cu(I)-perovskites with high photoluminescence quantum yield (PLQY) and stability remains challenge. Herein, a facile and reliable strategy towards CsCu2I3 nanocrystals composites (CsCu2I3/P-NCCs) by ion–dipole interaction induced space-confined growth within polymer is reported. The greatly enhanced PLQY and superior stability against external stimuli (i.e., UV-irradiation, heat, oxygen/moisture, polar solvents) are primarily attributed to the strong ion–dipole interaction (ΔG = −10.20 eV) between polyethyleneglycol (PEG) and precursor/perovskites as revealed by DFT simulation and experiments, which is unidentified in previous literature. The exceptional optical performance and stability enable the promising application of CsCu2I3/P-NCCs in white light-emitting diode (WLED) and anti-counterfeiting, delivering unprecedented color-rendering index (CRI of 95.4) and long half-life time (984h) under continuous illumination, as well as compositional engineered multi-model encryption/decryption. This work demonstrates that the association of weak force has significant influence on perovskites, providing an original principle for the synthesis and application of strongly-emissive and highly-stable perovskites.

Ion-Dipole Interaction Enabling Highly Efficient CsPbI3 Perovskite Indoor Photovoltaics.

Metal halide perovskites are ideal candidates for indoor photovoltaics (IPVs) because of their easy-to-adjust bandgaps, which can be designed to cover the spectrum of any artificial light source. However, the serious non-radiative carrier recombination under low light illumination restrains the application of perovskite-based IPVs (PIPVs). Herein, polar molecules of amino naphthalene sulfonates are employed to functionalize the TiO2 substrate, anchoring the CsPbI3 perovskite crystal grains with a strong ion-dipole interaction between the molecule-level polar interlayer and the ionic perovskite film. The resulting high-quality CsPbI3 films with the merit of defect-immunity and large shunt resistance under low light conditions enable the corresponding PIPVs with an indoor power conversion efficiency of up to 41.2% (Pin : 334.11µWcm-2 , Pout : 137.66µWcm-2 ) under illumination from a commonly used indoor light-emitting diode light source (2956 K, 1062 lux). Furthermore, the device also achieves efficiencies of 29.45% (Pout : 9.80µWcm-2 ) and 32.54% (Pout : 54.34µWcm-2 ) at 106 (Pin : 33.84µWcm-2 ) and 522 lux (Pin : 168.21µWcm-2 ), respectively.

Dynamic cross-linking of zwitterionic polymer binder based on host–guest interactions for Li-S batteries with enhanced safety and electrochemical performance

The commercial application of lithium–sulfur (Li–S) batteries is gravely hindered by the large volume alteration, lithium polysulfides shuttling, poor ion conduction, and safety concerns. Especially under lean electrolyte and high S-loaded operation, the dramatic volume change and slow ion transport efficiency may cause a rapid capacity fading, inferior reversible capacity, and even security hazards. Herein, a dynamic cross-linking zwitterionic supramolecular binder (β-CDp-Cg-2AD) is skillfully designed to confront these issues. The amphiphilic zwitterionic would contribute to immobilize lithium polysulfide and promoting the polysulfides redox kinetics through the strong ion–dipole interactions, along with the formation of PO4--Li+ and RNH3+-S42- pairs and electron transfer. Meanwhile, the dynamic cross-linking system based on host-guest interactions enables robust cathodes to withstand volume changes and provide a relatively low cross-linking density for Li+ transmission. Combining with a wealth of oxygen heteroatoms and like polyether chain segment, the Li+ transport efficiency is further enhanced through polymer chains thermal motion in β-CDp-Cg-2AD electrode. Benefiting from these attributes, even under 7.36 mg cm−2 S-loaded and sparing electrolyte of 7.1 µL mg−1, the β-CDp-Cg-2AD electrode can also remain a high areal specific capacity of 7.60 mAh cm−2 and 96 % capacity retention after 100 cycles. Moreover, the TG-FTIR test is performed to explore the flame-retardant mechanism of β-CDp-Cg-2AD, indicating their fire safety improvement. This work not only provides a high-performance and safety improvement binder for the practical application, but inspires the exploration of the flame-retardant mechanism of all electrode components.

Harnessing ion–dipole interactions: a simple and effective approach to high-performance lithium receptors

Incorporating strong ion–dipole interactions within acyclic molecular frameworks can remarkably enhance both binding affinity and selectivity for lithium ion, offering a simple and effective strategy for developing high-performance lithium receptors.

Novel Deep Eutectic Electrolyte Induced by Na···N Interactions for Sodium Batteries

Described herein presents a class of novel deep eutectic electrolytes (DEEs) with distinctive properties for sodium batteries. Instead of being limited by the presence of a hydrogen bond donor (HBD) or hydrogen bond acceptor (HBA), the concept of Na···N interactions was first brought in between sodium bis(fluorosulfonyl)imide (NaFSI) and 1,2-dimethylimidazole (DMIm). The deep eutectic phenomenon was caused by the strong ion–dipole interaction, which was conducive to the release of Na+ from NaFSI and drove the DEE with a desirable ionic conductivity. Furthermore, the proposed mechanism of Na···N interactions was credibly confirmed by Raman, 23Na NMR, and theoretical calculations. The half-cell based on NaFSI/DMIm–1/4 can provide a reversible capacity of 316.7 mAh·g–1 at 0.05 A·g–1, and Coulombic efficiency remains 91% after 500 charge–discharge cycles at 1.0 A·g–1 in the application of sodium batteries. It is anticipated that this work will present distinct insights into the extension of electrolytes for sodium batteries.

Constructing practical micron silicon anodes via a homogeneous and robust network binder induced by a strong-affinity inorganic oligomer

Designing robust binders has been demonstrated to be an effective and facile strategy to stabilize Si anodes. However, the binders that performed well for Si nanoparticles are not applicable for low-cost and accessible Si micron-powders. Hence, a novel binder design strategy is still greatly required for practical micron-Si anodes. Herein, a robust water-based network binder (named as c-PTP-Alg) has been designed via coupling potassium tripolyphosphate (PTP) inorganic oligomer with alginic acid (Alg) organic macromolecule. Owing to the unique structure of PTP, a network with high mechanical resistance can be constructed in c-PTP-Alg binder via strong ion-dipole interactions. Moreover, the highly soluble and dispersed PTP inorganic oligomer in water prevents the organic macromolecule from aggregation. This induces a homogeneous texture in the c-PTP-Alg binder, which enables the polar groups in the composite binder to anchor micron-Si particles efficiently. Therefore, by simply applying the c-PTP-Alg binder, a significantly improved electrochemical performance of micron-Si anode with a high reversible capacity of 1599.9 mAh g−1 after 100 cycles at 3000 mA g−1 has been obtained. More specially, the high-energy-density Si||S-PAN full cells have also been constructed, showing the practical application prospect of the c-PTP-Alg binder.

Differentiating the Structure and Dynamics of Solute-Bound Vs. Bulk Water in Deep-Eutectic Aqueous AlCl3 Solutions

Aqueous solutions of aluminum chloride exhibit a deep eutectic (-52˚C) that is likely due to solute-directed formation of complex network structures in the solvent. It is well known that the solute-bound solvent must have a distinct chemical environment from that of the bulk solvent. Commonly used vibrational spectroscopic measurements of aqueous salt solutions are not selective enough to directly identify distinct water environments in solution. However, variable-temperature 1H-NMR spectroscopy of aqueous solutions, specifically those with high charge density salts, can distinguish water directly bound to the cation from water of the bulk solution. This unique ability to resolve characteristic water peaks by NMR spectroscopy affords the opportunity to explore the hydration structure and dynamics of deep-eutectic aqueous solutions. The aqueous AlCl3 system is an excellent model to study solution structure since we can exploit the high charge density of the ions for which strong ion-dipole interactions are structure-directing to the solvent waters, allowing resolution of distinct water chemical environments. We conducted a thorough investigation of the composition- and temperature-dependent solution structure of the AlCl3 : water system using 1H-NMR spectroscopy, and X-ray and neutron diffraction. The room-temperature proton chemical shift of water proceeds downfield with increasing salt concentration until AlCl3•22H2O, the eutectic composition, after which further increasing concentration results in an upfield chemical shift (see Figure.) Using VT-NMR, we can resolve the first-nearest neighbor water signals from the bulk signal upon cooling. 1H-NMR T1 and T2 relaxation measurement of the distinct water environments reveal stark differences in proton mobility for compositions on the water-rich versus AlCl3-rich sides of the eutectic, implying significant changes in hydration structure. To evaluate the extent to which these changes are structural, a parallel set of composition- and temperature-dependent neutron and X-ray diffraction experiments demonstrate that both cations and anions exhibit significant structure-directing influences on the solution, which we hypothesize underlies deep eutectic behavior in aqueous solutions. Figure 1

A cation-dipole-reinforced elastic polymer electrolyte enabling long-cycling quasi-solid-state lithium metal batteries

The application of ionic liquids (IL) in polymer electrolytes represents a safer alternative to the currently used organic solvents in lithium batteries due to their nonflammability and thermal stability. However, as a plasticizer, it is generally agreed that the introduction of ionic liquid usually leads to a trade-off between ion transport and mechanical properties of polymer electrolyte. Here we report the synthesis of an IL-embedded polymer electrolyte with both high ionic conductivity (2.77 × 10−4 S cm−1 at room temperature) and excellent mechanical properties (high tensile strength up to 11.4 MPa and excellent stretchability of 387% elongation at break) achieved by strong ion–dipole interactions between polymer electrolyte components, which was unveiled by the DFT calculation. Moreover, this polymer electrolyte also exhibits nonflammability, good thermal stability and the ability to recover reversibly from applied stress, i.e., excellent elasticity. This highly viscoelastic polymer electrolyte enables tight interfacial contact and good adaptability with electrodes for stable lithium stripping/plating for 2000 h under a current density of 0.1 mA cm−2. By coupling with this polymer electrolyte, the LiFePO4/Li cells exhibit outstanding cycling stability at room temperature as well as the reliability under extreme environmental temperature or being abused.

Structural organization of ionic liquids embedded in fluorinated polymers

• Hybrid materials based on ionic liquids (ILs) and PVDF were produced by solvent casting. • The structural organization of different ILs incorporated into PVDF were determined. • The morphology depends on the structural organization of ILs into the PVDF matrix. • A single IL polydispersion favors the ion-dipole interactions between the Il and PVDF matrix. Hybrid materials based on ionic liquids (ILs) and polymers are increasingly being used for the development of smart and multifunctional materials, allowing to tune polymer properties or introduce new ones. Nonetheless, the structural organization of ILs within the polymer matrix is not properly understood. This work reports on the structural organization of different ILs incorporated into polyvinylidene fluoride (PVDF) films. The effect of IL type ([Pmim][TFSI], [Pmpip][TFSI], [Bmim] 2 [NiCl 4 ] and [Bmim][FeCl 4 ]) incorporated into the PVDF matrix on the structural organization was evaluated and correlated to the observed variations in the morphological and physical-chemical properties. [Bmim][FeCl 4 ] and [Bmim] 2 [NiCl 4 ] leads to highly porous structures and the incorporation of ILs into the polymer matrix increases the electroactive β phase content of PVDF. Different structural organization of the hybrid materials at nanoscale has been found by small-angle neutron scattering experiments. Whereas just single polydisperse objects with average size of about 5 nm have been found in PVDF/[Pmim][TFSI] and PVDF/[Pmpip][TFSI] samples, more complex fractal-like organization of pores are present in PVDF/[Bmim][FeCl 4 ] and PVDF/[Bmim] 2 [NiCl 4 ]. Thus, IL type influences both the morphology and the electroactive phase of the polymer. Complex fractal-like organization observed for [Bmim][FeCl 4 ] and [Bmim] 2 [NiCl 4 ] into the PVDF matrix allows a porous morphology, while single polydispersed [Pmpip][TFSI] or [Pmpip][TFSI] into PVDF favors strong ion-dipole interactions between the IL and the polymer matrix, resulting in higher electroactive β phase contents.

Enhanced stretchability and robustness towards flexible ionotronics via double-network structure and ion-dipole interactions

Ionic conductive gels enabled by ionic liquids (ionogels) are promising candidates for flexible electronics due to less concerns on liquid evaporation and leakage. However, it is still a challenge to simultaneously enhance the strength and stretchability for an ionogel. Here, we report a mechanically robust and stretchable ionogel, employing fluorinated acrylic monomers to construct double network (DN) structure and ion-dipole interactions between ionic liquid and the resulted polymer backbone. The highly transparent ionogels present excellent mechanical properties, with ultimate stretchability up to 784% and strength 5.6 MPa. Noticeably, the addition of ionic liquid up to 30% results in a substantial increase of stretchablity without sacrificing the ultimate stress, due to the strong ion-dipole interactions. With a good conductivity (10−4 to 10−5 S cm−1), the ionogels can be used as flexible conductors for electroluminescent devices and wearable strain sensors, both displaying excellent performance. This study provides a practical strategy on the fabrication of robust and stretchable ionogels for flexible ionotronics.

Impact of Magnesium Salt on the Mechanical and Thermal Properties of Poly(vinyl alcohol).

The effects of magnesium salts with various anion species on the structure and properties of a poly(vinyl alcohol) (PVA) film were studied. The glass transition temperature of the PVA film increased following the addition of a magnesium salt. Furthermore, the salt greatly enhanced the modulus and yield stress and reduced the crystallinity of the film. These effects were attributed to the strong ion–dipole interactions between the magnesium salts and the PVA chains. The strength of interaction, i.e., the reduction of segmental motions, depended on the anion species in the following order: Mg(ClO4)2, MgBr2, MgCl2, Mg(CH3COO)2, and MgSO4. The order corresponded to the Hofmeister series, which predicts the ability to break the structure of water.

Developments on Synthesis and Applications of Sulfobetaine Derivatives: A Brief Review

Zwitterionic polymers are material families characterized by high dipole moment and highly charged groups. Zwitterionic materials simultaneously possess an equimolar number of cationic and anionic moieties, maintaining overall electroneutrality and high hydrophilicity. Zwitterionic is categorized into three groups: phosphobetaine, carboxybetaine, and sulfobetaine that could form dense and stable hydration shells through the strong ion-dipole interaction among water molecules and zwitterions. As a result of their remarkable hydration capability, low interfacial energy, and marvelous antifouling capacities, these materials have been applied as adsorbing agents, biomedical applications, electronics, hydrogels, and antifouling for membrane separation and marine coatings. This review is focused on polysulfobetaine, which contains sulfonate as a negatively charged group, and quaternary ammonium as a positively charged group. Polysulfobetaine is the most promising one to be applied in the industry since it is commercially available and its monomers are easily prepared. The comparisons of several polysulfobetaine derivatives as antimicrobial, antifouling, surfactant and detergents, biomedical and electronic application, surface modification, and smart hydrogel are presented in this review.

Organosulfide-Based Deep Eutectic Electrolyte for Lithium Batteries.

Deep eutectic electrolytes (DEEs) are a new class of electrolytes with unique properties. However, the intermolecular interactions of DEEs are mostly dominated by Li⋅⋅⋅O interactions, limiting the diversity of chemical space and material constituents. Herein, we report a new class of DEEs induced by Li⋅⋅⋅N interactions between 2,2'-dipyridyl disulfide (DpyDS) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The strong ion-dipole interaction triggers the deep eutectic phenomenon, thus liberating the Li+ from LiTFSI and endowing the DEEs with promising ionic conductivity. These DEEs show admirable intrinsic safety, which cannot be ignited by flame. The DEE at the molar ratio of DpyDS:LiTFSI=4:1 (abbreviated as DEE-4:1) is electrochemically stable between 2.1 and 4.0 V vs. Li/Li+ , and exhibits an ionic conductivity of 1.5×10-4 S cm-1 at 50 °C. The Li/LiFePO4 half cell with DEE-4:1 can provide a reversible capacity of 130 mAh g-1 and Coulombic efficiency above 98 % at 50 °C.

Handheld device for rapid detection of lead (Pb2+) in gunshot residue for forensic application

The present work describes an innovative handheld device for rapid detection of Lead (Pb2+) in Gunshot residues (GSR). Our method is very sensitive, selective and specific for not only qualitative but also quantitative detection of Pb2+ in various GSR samples. It is based on the principle of shift in Light Scattering Plasmon Resonance (LSPR) of Poly Vinyl Alcohol (PVA) Capped Silver Nanoparticles (AgNPs) from 410.5 nm to 590 nm which occur due to strong ion dipole interaction between Pb2+ and PVA capped silver nanoparticles leading to change in color. Various parameters were optimized and characterized using several instruments. Qualitative detection was made visually by naked eyes with a change in color using microliter of samples. Various GSR samples were collected from different ammunition fired at varying range on cloth piece. The results were compared and correlated with standard known methods such as Atomic Absorption Spectroscopy (AAS) and UV–Vis spectroscopy. The method showed linearity in the range from 0.01 to 10 ppm with limit of detection (LOD) of 1.02 ppm (R2 = 0.98). No interfering effect was observed in the presence of several other metal ions such as Cu2+, Mg2+, Ca2+, Ba2+, Hg2+, Cr3+ etc. This low cost, rapid, colorimetric method tested using handheld device for Pb2+ detection in GSR underlines the onsite applicability of this method and helpful in determining the range and type of ammunition used which would further help forensic scientist.

Application of the Hofmeister series to the structure and properties of poly(vinyl alcohol) films containing metal salts

The effects of ions on the structures and properties of poly(vinyl alcohol) films were systematically studied using various metal salts. Although cations play an important role, the data obtained in this study demonstrated that the strong ion–dipole interactions between anions and poly(vinyl alcohol) chains also have a significant impact on crystallinity and glass transition temperature. For the first time, the study revealed that the impact of the added salts follows the Hofmeister series. Investigations of various bromine salt cations revealed that Li+ is more effective at disrupting the water structure than either Na+ or K+. Further experiments using lithium salts with various anion species verified that lithium salts play an important role in determining the crystallinity and hydrogen bonding within aqueous poly(vinyl alcohol) and therefore affect the dynamic mechanical properties of films. This phenomenon clearly follows the order LiClO4 > LiI > LiBr > LiNO3 > LiCl, which corresponds to the Hofmeister series. The salt addition affects the structure and properties of poly(vinyl alcohol) films as it reduces the hydrogen bonding in PVA chains and decreases the crystallinity. Consequently, the Tg shifts to low temperatures, and the modulus beyond Tg decreases markedly. This study confirmed that the impact of bromine salts on the structure and properties followed the order of Hofmeister series, i.e., Li+ > Na+ > K+. Although cations play an important role, the data obtained also demonstrated that the strong ion–dipole interactions between anions and PVA chains have a significant impact on the crystallinity and Tg.

Quantification of the ion transport mechanism in protective polymer coatings on lithium metal anodes.

Protective Polymer Coatings (PPCs) have been proposed to protect lithium metal anodes in rechargeable batteries to stabilize the Li/electrolyte interface and to extend the cycle life by reducing parasitic reactions and improving the lithium deposition morphology. However, the ion transport mechanism in PPCs remains unclear. Specifically, the degree of polymer swelling in the electrolyte and the influence of polymer/solvent/ion interactions are never quantified. Here we use poly(acrylonitrile-co-butadiene) (PAN–PBD) with controlled cross-link densities to quantify how the swelling ratio of the PPC affects conductivity, Li+ ion selectivity, activation energy, and rheological properties. The large difference in polarities between PAN (polar) and PBD (non-polar) segments allows the comparison of PPC properties when swollen in carbonate (high polarity) and ether (low polarity) electrolytes, which are the two most common classes of electrolytes. We find that a low swelling ratio of the PPC increases the transference number of Li+ ions while decreasing the conductivity. The activation energy only increases when the PPC is swollen in the carbonate electrolyte because of the strong ion–dipole interaction in the PAN phase, which is absent in the non-polar PBD phase. Theoretical models using Hansen solubility parameters and a percolation model have been shown to be effective in predicting the swelling behavior of PPCs in organic solvents and to estimate the conductivity. The trade-off between conductivity and the transference number is the primary challenge for PPCs. Our study provides general guidelines for PPC design, which favors the use of non-polar polymers with low polarity organic electrolytes.

Ionization–liquid‐crystalline polymer synergistically reinforced poly(ethylene terephthalate) due to interfacial compatibilization by ion–dipole interactions

AbstractTo enhance the compatibility of poly(ethylene terephthalate) (PET)/liquid crystalline polymer (LCP) composite, thereby mechanically strengthening the PET matrix, an optimally compatibilized composite of chain‐extended and ‐carboxylated PET ionomer and poly(4‐hydroxybenzoic acid–ran–6‐hydroxy‐2‐naphthoic acid) (HBA–HNA) was successfully prepared. Upon PET carboxylated chain extension with pyromellitic dianhydride and subsequent ionization with Zn(OH)2, the compatibility of the composite was distinctly improved, as verified by the refined dispersed‐phase morphology, increased number of refined HBA–HNA fibrils, reduced crystallinity, and improved complex viscosity. Compared with PET, the optimally compatibilized composite displayed a 70.1 and 148.7% increase in Young's modulus and tensile strength, respectively. Tentatively mechanistically, the interfacial interaction may change from weak hydrogen bonding to strong ion–dipole interactions due to the introduction of ionic groups, which remarkably boosts the interfacial compatibility, thereby achieving synergistic effects of the ionization and HBA–HNA inclusion to maximally strengthen PET. It seems that the synergistic ionization/LCP inclusion by a one‐pot method establishes a promising preparation approach to commercial PET engineering resins.