Excellent Interfacial Compatibility Research Articles

Polycarbonate-based composite polymer electrolytes with Al2O3 enhanced by in situ polymerized electrolyte Interlayers for all-solid-state lithium-metal batteries

Lithium-metal batteries (LMBs) have attracted significant attention as promising energy storage devices due to their high energy density. However, the practical application of LMBs is hindered by issues such as dendrite growth and electrolyte decomposition, which lead to poor cycling stability. To address these challenges, this study focuses on investigating the performance of poly(ethylene carbonate) (PEC)-based composite polymer electrolytes (CPEs) with an in situ polymerized poly(vinyl ethylene carbonate) (PVEC)-based electrolyte interlayer. The electrolytes were optimized by incorporating lithium bis(fluorosulfonyl)imide (LiFSI) salt, lithium bis(oxalato)borate (LiBOB) and lithium nitrate (LiNO3) additives, as well as Al2O3 filler. The objective was to improve the compatibility and cycling stability of LMBs by enhancing the electrolyte/electrode interfacial properties. Remarkably, the Li||Li symmetric cell utilizing the optimized CPE exhibited outstanding stability, operating for 700 h without short-circuiting at 0.1 mA cm−2, indicating excellent interfacial compatibility. Additionally, the Li||LiFePO4(LFP) cells using the same electrolyte demonstrated impressive performance, delivering initial discharge capacity of 159.32 mAh g−1 at 0.1 C with retention and coulombic efficiency close to 100 % after 100 cycles at 60 °C. This paper highlights the effectiveness of utilizing polymer electrolyte interlayers and additives like LiNO3 in CPEs to enhance the interfacial compatibility and cycling stability of LMBs.

Coconstruction of Supramolecular Lithium-Conducting Cross-Linked Networks Based on PVDF and Triblock Polymer Nanomicrosphere Solid-State Polymer Electrolytes for Lithium-Metal Batteries.

Uneven lithium plating and low ionic conductivity currently impede the realization of high-capacity rechargeable lithium metal batteries. And the conventional poly(ethylene oxide) (PEO) solid-state electrolytes are unsuitable for high-energy-density Li anode applications due to their low lithium-ion transference number and high reactivity with Li metal, leading to detrimental dendrite formation and potentially hazardous exothermic reactions with the electrolyte. In this study, we employ a supramolecular approach to develop a novel polymer solid-state electrolyte based on poly(vinylidene fluoride) (PVDF) and a novel triblock polymer nanomicrosphere, (poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone), (PCL-PEG-PCL). The abundance of carbonyl and ether-oxygen functional groups in PCL-PEG-PCL enhances the lithium coordination environment within the polymer solid-state electrolyte. Additionally, the original C-F moieties of PVDF form hydrogen bonds with C-H and terminal hydroxyl groups in PCL-PEG-PCL, collectively creating a multichannel fast Li+-conducting supramolecular cross-linked network. The resulting electrolyte demonstrates a high ionic conductivity of 1.4 × 10-3 S cm-1 and an extended electrochemical window of 5.2 V. Moreover, the electrolyte exhibits a high lithium-ion transference number (tLi+ = 0.63) at room temperature and exhibits excellent interfacial compatibility with the lithium metal anode. For the resulting electrolyte utilized in LiFePO4 batteries, the capacity retention of the cells assembled with this electrolyte exceeds 91.3% after 1000 cycles at 25 °C and 2 C (0.281 mA cm-2).

Interfacial compatible PolyMOF membranes as ratiometric fluorescence temperature sensors

Cryogenic temperature sensors play significant roles in manufacturing, metallurgy, and aerospace. Metal-organic frameworks (MOFs) as emerging crystal materials exhibited inherent advantages as fluorescence temperature sensors and researchers have shifted their focus toward incorporating MOFs materials into mixed matrix membranes (MMMs) for broader practical applications. However, the poor interfacial compatibility between MOFs particles and the polymer matrix would cause aggregation-induced fluorescence quenching and reduced energy transfer efficiency, thereby compromising temperature sensing performances. Herein, we adopt a post-synthetic copolymerization strategy to realize an interfacial-compatible membranous ratiometric luminescent thermometer based on the emissions of ligands and lanthanide ions. Benefiting from the controllable covalent cross-linking structures, the designed polyMOF membrane exhibited excellent interfacial compatibility and avoided MOFs irregular morphology agglomeration and phase separation, which contributed to outstanding fluorescence temperature sensing performance with excellent sensitivity ranging from 0.300 to 0.745 %·K−1 within the temperature range of 80–300 K, superior to recent reported MOFs-based thermometers. This research presents a promising approach for the design and fabrication of interfacial compatible MOFs-based membranes with excellent fluorescence temperature sensing properties, advancing the understanding of structure-property relationships and accelerating the practical applications.

Covalently assembling multi-dimensional carbon-based nanoclay composites via ionic liquid linkers into PVA membrane for molecular separation

The application of membrane-based separation technology in purifying azeotropic solutions plays a crucial role in minimizing energy consumption during reactive distillation. The strategic integration of multi-dimensional structural composites within mixed matrix membranes (MMMs), characterized by a robust framework and efficient molecular transport channels, poses challenges but demonstrates significant potential for advancing the development of high-performance membrane fabrication. Herein, we proposed a novel strategy to covalently assemble halloysite nanotubes (HNTs) and graphene oxide (GO) using ionic liquids (ILs) as linkers. When incorporated into the polyvinyl alcohol (PVA) matrix, the ILs@HNTs@GO (IHGO) composites exhibit excellent interfacial compatibility, and ILs also enhanced the composite’s selective transfer ability to water molecules. The optimal separation performance for pervaporation dehydration from a ternary solution was respectively 2.57 (selectivity) and 1.74 (permeability) times higher than those of the pristine PVA membrane. The structural stability of the MMMs and their separation mechanism has been comprehensively validated by adjusting the content of GO in IHGO composites and conducting simulations. This study holds significant theoretical and practical implications for organic compounds purification, while simultaneously paving new avenues for the fabrication of structurally robust and high-performance MMMs with optimal filler effectiveness.

Excellent interfacial compatibility of phase change capsules/polyurethane foam with enhanced mechanical and thermal insulation properties for thermal energy storage

The incorporation of phase change microcapsule (microPCMs) substantially augmented the temperature regulation capacity of foams, endowing it with outstanding application potential in numerous industrial domains. However, interfacial compatibility issues between the capsule and the substrate always exist and affect foam performance. In this study, a milli-meter macrocapsule (macroPCMs) containing microPCMs was prepared using calcium alginate gel as the second layer wall to physically improve the interfacial compatibility. And poly (N-hydroxymethyl acrylamide) was in situ polymerized in the gel layer and provided active alcohol hydroxyl groups to form chemical grafting with the polyurethane raw materials, which further chemically improved the interfacial compatibility. These measures created a significantly improved foam microstructure and a greatly increased foaming capacity, which thus endow the composite foam with excellent thermal insulation performance and mechanical strength. Compared with conventional microPCMs-based foam, the foaming capacity of the macroPCMs-based foam increased by 40 folds, the temperature regulation duration increased by 7 folds, and the mechanical performance increased by 3 folds. Moreover, the insulated incubator fabricated with the macroPCMs-based foam exhibited two-fold greater thermal insulation efficiency than conventional models containing internal ice incubator, which validated the potential of employing macroPCMs-based polyurethane foam in cold chain logistics applications.

Self‐emulsification synthesis of epoxy phosphate ester and its flame‐retardant mechanism in flexible poly(vinyl chloride)/magnesium hydroxide composites

AbstractA trade‐off dilemma exists for simultaneously improving the mechanical properties and flame resistance of flexible polyvinyl chloride (fPVC)/magnesium hydroxide (MH) composites. In this study, epoxy phosphate ester (EPE), a hydrophobic surface modifier of MH, was synthesized using a self‐emulsification method. After modification, EPE was bonded to the surface of MH (MHEPE) without altering its morphology. The results of limiting oxygen index and cone calorimetry tests indicated that fPVC/MHEPE exhibited better flame retardancy and smoke suppression effects than did fPVC/MH. The peak of the heat release rate, total heat release, peak of the smoke production rate, and total smoke production of the fPVC/MHEPE composite were 206.0 kJ m−2, 45.90 MJ m−2, 0.0729 m2 s−1, and 9.88 m2, which were 8.64%, 14.00%, 27.61%, and 9.02% lower than those of the fPVC/MH composite, respectively. For the fPVC/MHEPE composite, a compact and continuous char residue formed, which could inhibit heat and flammable volatile migration between the matrix and burning zones. In the gas phase, the dilution effect of H2O vapor reduced the concentrations of O2 and flammable volatiles. The free‐radical quenching effect of ·PO and ·PO2 also played a vital role in extinguishing flame and terminating combustion. Further, the introduction of EPE improved the tensile and impact strengths of the fPVC/MH composites because of the excellent interfacial compatibility between MHEPE and the fPVC matrix. This study provides a simple and workable solution for the trade‐off dilemma, and the remarkable flame retardancy and mechanical properties of the fPVC/MHEPE composite render it a promising cable material.

Laminated composite fabricated using high-performance polyamine thermoset: Ultra heat resistance and excellent mechanical property

Developing polymer composites that can work in harsh environment are important for advancing materials industry. However, the composites generally based-on epoxy or phenolics resins that can endure both extremely high and low temperature are still rather limited. In this work, melamine-hexamethylenediamine (MH) thermoset which is structurally different from conventional matrices was used as matrix resin for woven glass fiber reinforced MH (GFRMH) laminated composite. Owing to the excellent thermostability (Td ≈ 460 °C) and interfacial compatibility of the MH matrix, the fabricated composites exhibited exceptional resistance to extreme temperature and mechanical performances, which are superior to that of the representative commercial epoxy-based composites. Particularly, the heat deflection temperature (HDT) of GFRMH was above 300 °C which is much higher than that of the representative high-performance commercial composites (220–270 °C). Moreover, GFRMH composite exhibited excellent retainability even at 425 °C while severe carbonization and delamination occurred to all the selected commercial products. Further, the GFRMH laminate exhibited flexural strength of 541 MPa at room temperature, higher than that of the commercial products by 80–160 MPa. Remarkably, the flexural strength increased to 852 MPa at 77 K without declining of toughness, suggesting the excellent resistance to cryogenic temperature. In summary, the results of the study disclosed the suitability of MH resin as a new matrix of glass fiber reinforced engineering materials.

A wrapped and infiltrated ∼20-μm-thick 3D ceramic framework composite enables fast Li+ diffusion and interfacial compatibility for lithium-metal batteries

Composite polymer electrolytes (CPEs) have shown potential for energy-dense Li-metal batteries (LMBs), but CPEs have always encountered poor ionic conductivity, low Li+ transference ability, and dendrite propagation. In our work, a mechanically robust three-dimensional porous framework (3DPF) with a thickness of ∼21 μm was successfully prepared by tape-casting and firing Li6.75La3Zr1.75Ta0.25O12 (LLZTO). After wrapping and infiltrating poly(vinylidene fluoride) (PVDF)−salt (LiTFSI)−LLZTO solution to 3DPF (3DPF-PVDF-LLZTO) for subsequent solidification, the resultant composite electrolyte (∼22 μm) shows an excellent room-temperature ionic conductivity of 1.67 × 10−4 S cm−1 and an extremely high Li+ transference number of 0.82, indicating fast Li+ diffusion. Furthermore, 3DPF-PVDF-LLZTO exhibits a mechanical strength of 37.5 MPa, and the assembled Li|3DPF-PVDF-LLZTO|Li cell ensures stable operation at 1.0 mA cm−2 and presents prolonged cycling stability at 0.2 mA cm−2 over 800 h without exhibiting dendrites, demonstrating excellent interfacial compatibility. A Li|3DPF-PVDF-LLZTO|LiFePO4 battery delivers excellent room-temperature cycle stability and rate capability, with an initial capacity of 160.7 mAh g−1 at 0.2 C and 115.3 mAh g−1 over 450 cycles at 1.0 C. This work provides a practical strategy for constructing highly conductive composite electrolytes with electrode−electrolyte compatibility for LMBs and deepens our understanding of Li+ diffusion pathways.

Zwitterionic Polyurethane Solid Polymer Electrolytes: A Pathway to High-Performance All-Solid-State Lithium-Ion Batteries

Lithium-ion batteries (LIBs) currently dominate the energy storage market for electronic devices, thanks to their high energy density, high operating voltage, and good cycling performance. However, commercial LIBs employing organic liquid electrolyte and lithium (Li) salts pose significant safety concerns, including flammability and the risk of thermal runaway. Consequently, the development of solid electrolytes is of paramount importance. Among several solid ion conductors, solid polymer electrolytes (SPEs) can offer numerous advantages, including excellent flexibility and interfacial compatibility with electrodes, good processibility, low cost, and light weight characteristics. However, current SPEs face challenges such as poor thermal stability, inferior electrochemical stability, and low Li-ion conductivity at room temperature (~ 10-5 S cm-1 at 25 ℃).In this study, we introduce a multifunctional zwitterionic polyurethane-based solid polymer electrolyte (zPU-SPE) for all-solid-state LIBs (SLBs) that addresses the limitations of conventional SPE materials. We synthesized zPU [i.e., poly((diethanolamine ethyl acetate)-co-poly(tetrahydrofuran)-co-(1,6-diisocyanatohexane))] and demonstrated its capability to host high amounts of LiTFSI without phase separation (up to 90 wt% LiTFSI loading). The Li-ion conductivity of zPU-SPE at 25° C is 7.4 × 10-4 S/cm, nearly 14 times greater than that of poly(ethylene oxide) (PEO) SPE (EO/Li+ = 16). Moreover, the high surface energy of zPU-SPE (487.5 J/m2 vs. 1.39 J/m2 of PEO) minimizes interfacial resistance. The zPU-SPE also exhibits outstanding elasticity, with a tensile break of 1700%, attributable to its dense inter- and intra-molecular hydrogen bonding.We evaluated the SLB battery performance of PEO and zPU-SPEs using a solid-state Li/SPE/LiFePO4 cell, which we cycled at a constant current rate of 1 C at 25 °C. The SLB cell with zPU-SPE demonstrates remarkable cycle stability, retaining 86% capacity after 1,000 cycles and 76% capacity after 2,000 cycles at a 1C rate and room temperature, while maintaining nearly 100% coulombic efficiency. In contrast, the capacity of the SLB cell with PEO rapidly decreases to 30% of its initial capacity and fails after 100 cycles. Given that significant capacity loss in LIBs under cold weather conditions poses a challenge for electric vehicles, we also assessed the temperature-dependent battery performance. The SLB with zPU-SPE retains 93.8% capacity at 0 °C, a substantial improvement over state-of-the-art LIBs (< 80% capacity retention). We attribute the high-capacity retention of zPU-SPE at low temperatures to the excellent chain mobility of the soft segment in the zPU matrix, which has a low glass transition temperature (-45 °C) and a high ion transport rate due to the zwitterionic group. We also conducted atomistic molecular modeling to investigate the dissolution and dissociation of Li salts and the Li-ion transport mechanism within the zPU polymer matrix. Furthermore, we employed small-angle X-ray scattering to examine the structural organization of the zPU-SPE matrix and its correlation with ion conductivity. Our work aims to guide the design of novel polymer electrolytes capable of overcoming the trade-offs associated with ion-conducting polymers (i.e., stability and ion conductivity). Figure 1

Polyoxometalate Li3PW12O40 and Li3PMo12O40 Electrolytes for High‐energy All‐solid‐state Lithium Batteries

AbstractSolid‐state lithium (Li) batteries promise both high energy density and safety while existing solid‐state electrolytes (SSEs) fail to satisfy the rigorous requirements of battery operations. Herein, novel polyoxometalate SSEs, Li3PW12O40 and Li3PMo12O40, are synthesized, which exhibit excellent interfacial compatibility with electrodes and chemical stability, overcoming the limitations of conventional SSEs. A high ionic conductivity of 0.89 mS cm−1 and a low activation energy of 0.23 eV are obtained due to the optimized three‐dimensional Li+ migration network of Li3PW12O40. Li3PW12O40 exhibits a wide window of electrochemical stability that can both accommodate the Li anode and high‐voltage cathodes. As a result, all‐solid‐state Li metal batteries fabricated with Li/Li3PW12O40/LiNi0.5Co0.2Mn0.3O2 display a stable cycling up to 100 cycles with a cutoff voltage of 4.35 V and an areal capacity of more than 4 mAh cm−2, as well as a cost‐competitive SSEs price of $5.68 kg−1. Moreover, Li3PMo12O40 homologous to Li3PW12O40 was obtained via isomorphous substitution, which formed a low‐resistance interface with Li3PW12O40. Applications of Li3PW12O40 and Li3PMo12O40 in Li‐air batteries further demonstrate that long cycle life (650 cycles) can be achieved. This strategy provides a facile, low‐cost strategy to construct efficient and scalable solid polyoxometalate electrolytes for high‐energy solid‐state Li metal batteries.

Polyoxometalate Li3 PW12 O40 and Li3 PMo12 O40 Electrolytes for High-energy All-solid-state Lithium Batteries.

Solid-state lithium (Li) batteries promise both high energy density and safety while existing solid-state electrolytes (SSEs) fail to satisfy the rigorous requirements of battery operations. Herein, novel polyoxometalate SSEs, Li3 PW12 O40 and Li3 PMo12 O40 , are synthesized, which exhibit excellent interfacial compatibility with electrodes and chemical stability, overcoming the limitations of conventional SSEs. A high ionic conductivity of 0.89 mS cm-1 and a low activation energy of 0.23 eV are obtained due to the optimized three-dimensional Li+ migration network of Li3 PW12 O40 . Li3 PW12 O40 exhibits a wide window of electrochemical stability that can both accommodate the Li anode and high-voltage cathodes. As a result, all-solid-state Li metal batteries fabricated with Li/Li3 PW12 O40 /LiNi0.5 Co0.2 Mn0.3 O2 display a stable cycling up to 100 cycles with a cutoff voltage of 4.35 V and an areal capacity of more than 4 mAh cm-2 , as well as a cost-competitive SSEs price of $5.68 kg-1 . Moreover, Li3 PMo12 O40 homologous to Li3 PW12 O40 was obtained via isomorphous substitution, which formed a low-resistance interface with Li3 PW12 O40 . Applications of Li3 PW12 O40 and Li3 PMo12 O40 in Li-air batteries further demonstrate that long cycle life (650 cycles) can be achieved. This strategy provides a facile, low-cost strategy to construct efficient and scalable solid polyoxometalate electrolytes for high-energy solid-state Li metal batteries.

Green, recyclable, mechanically robust, wet-adhesive and ionically conductive cellulose-based bioplastics enabled by supramolecular covalent hydrophobic eutectic networks

The development of novel cellulose-based bioplastics (CBPs) is highly desirable because CBPs are green, rationally use resources, and lead to a reduction in environmental pollution compared to alternative materials. However, incorporating high transparency, water resistance, mechanical robustness, wet-adhesion, ionic conductivity and recyclability into CBP remains a challenge. In this paper, novel CBPs with supramolecular covalent networks are fabricated by introducing polymerizable hydrophobic deep eutectic solvents (HDES) into ethylcellulose (EC) networks through in situ plasticization followed by a rapid photopolymerization process. The excellent molecular interfacial compatibility enables EC to be loaded with a high content of poly(HDES), while allowing high transparency (more than 90 %) of the prepared CBPs. Multiple intermolecular interactions provide CBPs with mechanical robustness, water resistance, and underwater adhesion, and CBPs can be readily recovered by the solvent in a closed loop. Moreover, CBPs possess inherent ionic conductivities, and using them as green substrates, personalized electroluminescent devices can be successfully constructed. The method proposed in this paper provides a new strategy for the preparation of multifunctional CBPs, which will greatly enrich their applications in self-adhesive materials, green flexible electronics and other package materials.

Hierarchical bulk-interface design of MOFs framework for polymer electrolyte towards ultra-stable quasi-solid-state Li metal batteries

The sluggish ion transportation, oxidation instability and severe lithium dendrites impede the development of solid-state lithium metal battery (SSLMBs). Herein, a novel structural design of in-situ polymerized composite electrolyte (CPE) with the utilization of both orientationally arranged and unilaterally sedimented Zeolitic imidazolate framework-67 (ZIF-67) fillers are reported. The in-situ growing of ZIF-67 crystals on 3D polyvinylidene fluoride (PVDF) nanofiber skeleton not only provides high-speed Li+ conduction pathway, but also promotes the antioxidative ability of surrounding polymer matrix by facilitating the ring-open polymerization of 1,3-Dioxolane (DOL) monomer to form long-chain PDOL. Meanwhile, ZIF-67 deposition layer constructed through the natural sedimentation of residual ZIF-67 during PVDF@ZIF-67 framework fabrication regulates surface Li+ flux towards lithium anode and further optimizes SEI composition. As a result, satisfactory ionic conductivity of 1.8 × 10−4 S cm−1 and oxidative potential of 5.9 V (vs. Li+/Li) are acquired for unilateral-sedimented ZIF-67/PDOL CPE (UZE). Encouragingly, symmetric Li battery based on UZE displays a superior stability over 2300 h at 0.1 mA cm−2 and a remarkable cycle durability with 92.5 % of capacity retained after 570 cycles at 2C is also achieved for Li||LFP battery. This study provides a novel guidance in engineering solid electrolyte with excellent ionic transport kinetics and interfacial compatibility for next-generation SSLMBs.

Size effects of polydopamine-coated BaTiO3 nanoparticles on the piezoelectric performance of P(VDF-TrFE)/BaTiO3 composite

The size effect of the polydopamine (PDA)-coated BaTiO3 (BTO) (BTO@PDA) nanoparticles (NPs) on the interfacial compatibility between BTO NPs and the polymer matrix and the resultant piezoelectric performance of the composite films remain elusive. In this study, BTO and BTO@PDA NPs of various sizes were incorporated into a P(VDF-TrFE) matrix to prepare two series of P(VDF-TrFE)/BTO and P(VDF-TrFE)/BTO@PDA composites. Subsequently, the effects of the NP size on the dielectric, ferroelectric, and piezoelectric properties of the composite films were comprehensively studied. As the size of the BTO@PDA NPs increased, residual hole defects were clearly observed in the cross section of the composite film. The deteriorated interfacial compatibility due to the large size of the BTO@PDA NPs was also confirmed by the increased dielectric permittivity of the composite film, which was induced by the intensified interfacial polarisation. The P(VDF-TrFE)/BTO@PDA composite with NPs of the smallest size (100 nm) exhibited superior piezoelectric performance owing to the excellent interfacial compatibility between the fillers and the matrix. The piezoelectric performance was significantly enhanced by the reduced leakage current during electrical poling and reduced trap charges. Finally, the pulse waveform originating from the radial artery was precisely measured using the optimised P(VDF-TrFE)/BTO@PDA composite film.

A green organic-inorganic PAbz@ZIF hybrid towards efficient flame-retardant and smoke-suppressive epoxy coatings with enhanced mechanical properties

Developing sustainable bio-based flame retardants for flammable polymers has been a research trend. However, applying bio-based flame retardants to confer excellent flame retardancy, smoke suppression, and mechanical properties to polymers remains a formidable challenge. Herein, a green organic-inorganic hybrid (PAbz@ZIF) was readily prepared through a simple neutralization reaction and in-situ generation method and applied to fabricate high-performance flame-retardant epoxy coatings (EP-PAbz@ZIF). It has been shown that PAbz@ZIF hybrids can enhance the curing activity of epoxy coatings in addition to their excellent dispersibility and interfacial compatibility. In addition, the epoxy coating containing 5.0 wt% PAbz@ZIF (EP-5%PAbz@ZIF) exhibits a higher char yield (from 25.1 wt% to 31.5 wt%) in comparison to pristine epoxy resin (EP). More importantly, the PAbz@ZIF-based epoxy coatings show more efficient flame retardancy and smoke suppression compared to pristine EP. For instance, the 5.0 wt% PAbz@ZIF enables EP-5%PAbz@ZIF to obtain a satisfactory UL-94 rating of V0. Meanwhile, the peak heat release rate, total smoke production, peak CO production rate, and peak CO2 production rate of EP-5%PAbz@ZIF are remarkably decreased by 48.6%, 20.5%, 38.6%, and 56.7%, respectively. Furthermore, EP-5%PAbz@ZIF exhibits enhanced heat insulation performance, flexural strength, and impact strength. This work offers a feasible idea for designing green organic-inorganic PAbz@ZIF hybrids and fabricating high-performance flame-retardant epoxy coatings.

Innovative integration of pyrolyzed biomass into polyamide 11: Sustainable advancements through in situ polymerization for enhanced mechanical, thermal, and additive manufacturing properties

The incorporation of pyrolyzed biomass, i.e., biochar, in polymers can be viewed as a sustainable approach that reduces bio-waste in a smart way. Herein, various biochar concentrations were integrated into the biobased polyamide 11 (PA11) matrix via in situ polymerization. Scanning electron microscopy (SEM) micrographs demonstrated the homogeneous dispersion of up to 50 wt% biochar within the PA11 matrix, free from any phase separation, particle agglomeration, or crack formation. Consequently, there was a remarkable enhancement in mechanical and thermal properties. Notably, tensile strength and modulus increased by 35% and 72%, respectively, while the thermal decomposition process was significantly delayed with the incorporation of biochar particles. Furthermore, the viscoelastic performance of the PA11 matrix exhibited substantial improvement upon the addition of the filler particles. These impressive results verified the excellent interfacial compatibility achieved between the PA11 matrix and biochar, owing to the utilization of in situ polymerization. To demonstrate the potential application of these composites in additive manufacturing, a filament with a uniform diameter was fabricated from a composite comprising 50 wt% biochar. It was successfully employed in material extrusion to print a complex object. The resulting structure exhibited high shape fidelity, precise dimensions, and no noticeable defects. This groundbreaking strategy not only highlights the utilization of biochar as a sustainable filler but also underscores the efficacy of in situ polymerization in fabricating high-performance PA11/biochar composites for various demanding applications, including filament production for additive manufacturing.

Bamboo fiber strengthened poly(lactic acid) composites with enhanced interfacial compatibility through a multi-layered coating of synergistic treatment strategy

In this study, a mild and eco-friendly synergistic treatment strategy was investigated to improve the interfacial compatibility of bamboo fibers with poly(lactic acid). The characterization results in terms of the chemical structure, surface morphology, thermal properties, and water resistance properties demonstrated a homogeneous dispersion and excellent interfacial compatibility of the treated composites. The excellent interfacial compatibility is due to multi-layered coating of bamboo fibers using synergistic treatment involving dilute alkali pretreatment, polydopamine coating and silane coupling agent modification. The composites obtained using the proposed synergistic treatment strategy exhibited excellent mechanical properties. Optimal mechanical properties were observed for composites with synergistically treated bamboo fiber mass proportion of 20 %. The tensile strength, elongation at break and tensile modulus of the treated composites were increased by 63.06 %, 183.04 % and 259.04 %, respectively, compared to the untreated composites. This synergistic treatment strategy and the remarkable performance of the treated composites have a wide range of applicability in bio-composites (such as industrial packaging, automotive lightweight interiors, and consumer goods).

Straightforward Strategy Toward In Situ Water-Phase Exfoliation and Improved Interfacial Adhesion to Fabricate High-Performance Polypropylene/Graphene Nanocomposites.

Graphene is a potential candidate for achieving high-performance and multifunctional polypropylene (PP) composites. However, the complex manufacturing process and low dispersibility of graphene, as well as poor interfacial adhesion between graphene and polypropylene chains, stifle progress on large-scale production and applications of graphene/polypropylene composites. Here, we develop a strategy of maleic anhydride grafted polypropylene (MAPP) latex-assisted graphene exfoliation and melt blending to address the key challenges facing in industrial production. The surface property of the graphitic precursor is well-designed to achieve a high graphene exfoliation yield of ∼100% and induce abundant hydrogen bonding between the obtained mild-oxidized graphene (MOG) sheets and MAPP chains. Therefore, the MAPP-modified MOG can homogeneously disperse in the PP matrix and exhibits an excellent interfacial compatibility with the polymer. The addition of 5 wt % MOG results in simultaneous increase in the initial decomposition temperature, crystallization temperature, tensile strength, and Young's modulus by 43.2, 11.4 °C, 21.5, and 50.7%, respectively, and the electrical conductivity increases to 0.02 S·m-1. This work illustrates a practical solution to low-cost, eco-friendly, and feasible industrial production of graphene/PP composites through synchronous exfoliation and interfacial modification of graphene.

Progress and perspectives of in situ polymerization method for lithium‐based batteries

AbstractThe application of lithium‐based batteries is challenged by the safety issues of leakage and flammability of liquid electrolytes. Polymer electrolytes (PEs) can address issues to promote the practical use of lithium metal batteries. However, the traditional preparation of PEs such as the solution‐casting method requires a complicated preparation process, especially resulting in side solvents evaporation issues. The large thickness of traditional PEs reduces the energy density of the battery and increases the transport bottlenecks of lithium‐ion. Meanwhile, it is difficult to fill the voids of electrodes to achieve good contact between electrolyte and electrode. In situ polymerization appears as a facile method to prepare PEs possessing excellent interfacial compatibility with electrodes. Thus, thin and uniform electrolytes can be obtained. The interfacial impedance can be reduced, and the lithium‐ion transport throughput at the interface can be increased. The typical in situ polymerization process is to implant a precursor solution containing monomers into the cell and then in situ solidify the precursor under specific initiating conditions, and has been widely applied for the preparation of PEs and battery assembly. In this review, we focus on the preparation and application of in situ polymerization method in gel polymer electrolytes, solid polymer electrolytes, and composite polymer electrolytes, in which different kinds of monomers and reactions for in situ polymerization are discussed. In addition, the various compositions and structures of inorganic fillers, and their effects on the electrochemical properties are summarized. Finally, challenges and perspectives for the practical application of in situ polymerization methods in solid‐state lithium‐based batteries are reviewed.

Facile fabrication of novel fire-safe MXene@IL-based epoxy nanocomposite coatings with enhanced thermal conductivity and mechanical properties

In recent years, developing high-performance epoxy nanocomposite coatings with excellent fire safety, thermal conductivity, and mechanical performance has become a thorny challenge. Here, the multifunctional nanohybrid (MXene@IL) was facilely fabricated by an electrostatic self-assembly strategy, and epoxy nanocomposite coatings based on MXene@IL (EP/MXene@IL) were prepared. It has been found that MXene@IL nanohybrids exhibit excellent dispersion and interfacial compatibility in the epoxy matrix. Notably, the 2.0 wt% MXene@IL endows the epoxy nanocomposite coating with high fire safety, with a 43.76 % reduction in peak heat release rate and a 65.99 % reduction in smoke factor compared to virgin epoxy resin (EP), respectively. Meanwhile, the thermal conductivity (increased by 21.56 %) of EP/MXene@IL-2.0 is enhanced. Furthermore, the flexural and impact strengths of EP/MXene@IL-1.0 are improved by 10.24 % and 44.73 %, respectively. Interestingly, MXene@IL acts as a co-curing agent to facilitate the curing reaction of epoxy nanocoatings. This work provides a feasible strategy for designing multifunctional MXene@IL-based epoxy nanocomposite coatings.