Interfacial Polymerization Method Research Articles

Synthesis and Characterization of Polyaniline / [BMIM][BF4] Polyionic Liquid by Interfacial Polymerization

Polyaniline (PANI) was prepared by polymerization via the chemical oxidation of aniline monomer with ammonium persulfate as the initiator. The interfacial polymerization method was used to prepare PANI/1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] polyionic liquid (PIL). The obtained PANI/ [BMIM][BF4] PIL was investigated by the XRD, EDX, SEM, FTIR, and UV-Visible characterizations. X-ray diffractogram of PANI showed five prominent characteristic peaks at 27.1°, 24o, 21.8°, 19.8°, and 18.2°. This demonstrates the semi-crystalline character of the polyaniline produced through the interfacial polymerization process. Incorporation of [BMIM][BF4] into PANI reduced the crystalline phase and enhanced amorphicity. From the EDX pattern, several elements appeared in this test; oxygen had of the highest weight percentage of 54.2%. The SEM image showed a clear hierarchal porous structure with nano-sticks particles and forms a cross-linked framework between PANI and [BMIM][BF4]. From FTIR spectra of PIL, a prominent absorption peak at 3163.26 cm-1 was noted because of the N-H stretching vibrations present in the polymer. The UV-Vis spectra for PANI/[BMIM][BF4] polyionic liquid showed three peaks between 200 and 1060 nm. These bands result from π → π* and n → π* transitions, which are related to the excitement absorption of benzenoid and quinoid groups.

Tris-phenol phosphine oxide-based polyester loose nanofiltration membranes with a three-dimensional structure for efficient dye/salt separation

Loose nanofiltration (LNF) membranes prepared by hydroxyl monomers with good dye rejection and inorganic salt permeation properties have attracted significant attention for treating salt-containing textile wastewater. This study adopted interfacial polymerization (IP) method to fabricate a novel polyester LNF membrane, in which tris (4-hydroxyphenyl) phosphine oxide (THPPO) with a steric structure was employed as the solely aqueous monomer. To enhance the solubility and esterification reaction activity of THPPO, sodium hydroxide (NaOH) was specially adopted in aqueous phase, helping the development of the polyester selective layer. The findings demonstrated that the prepared ultrathin (30–38 nm) polyester selective layer exhibited a smooth surface with a negative charge. The optimal membrane LNF-0.05 exhibited a good water permeance of 20.8 L m−2h−1 bar−1, excellent rejection of anionic dyes (99.6 % for EBT, 99.3 % for CR, 98.8 % for DR 23, and 98.1 % for MB), and low rejection of monovalent salts (8.2 % for NaCl, 5.0 % for MgCl2), showing excellent EBT/NaCl mixture selectivity as high as 221. The performance stability of the membranes was partially testified by continuous filtration process. These results confirm the significant application potential of tris-phenol phosphine oxide-based polyester LNF membrane for treating saline textile wastewater.

Hybrid Self‐Repairing Polymer Composites Based on a Mixture of Intrinsic and Extrinsic Self‐Healing

AbstractThe development of high‐strength and multiple self‐healing polymer materials remains a major challenge. In this study, a hybrid self‐healable polymer using the combination of intrinsic and extrinsic self‐healing is demonstrated. The epoxy resin microcapsules with dynamic disulfide bonded shells are successfully prepared through an interfacial polymerization method, which are then added into the intrinsically self‐healable epoxy resin substrate also containing disulfide bonds. The unique combination structure enables the polymer composites to exhibit high mechanical strength and excellent multiple self‐healing efficiency. On the one hand, the Young's modulus and tensile strength of the material are enhanced due to the reinforcement effect of the fillers. On the other hand, the extrinsic self‐healing strategy of the microcapsules, which released repair agents, can support the intrinsic repairing substrate to improve the self‐healing ability of the material. More interestingly, the design of the disulfide bond structure of the microcapsule shell contributes to the high self‐healing capability of the material during multiple self‐healing processes.

Forward osmosis membrane substrates with low structure parameter: Modification with PSf‐g‐PMMA graft copolymer

AbstractIn this work, using the combination of atom transfer radical polymerization and click chemistry, the graft copolymer polysulfone‐graft‐poly (methyl methacrylate) (PSf‐g‐PMMA) was synthesized as a modifying agent. The copolymer was embedded in the PSf substrate using a nonsolvent phase inversion method. Then, the modified substrate was used to make thin film composite forward osmosis (TFC‐FO) membranes using the interfacial polymerization method. Also, the effect of PSf‐g‐PMMA copolymer content on the surface properties of the membrane, as well as the filtration performance, was investigated. The increase in hydrophilicity, porosity, and average pore diameter indicated the favorable effect of PSf‐g‐PMMA copolymer on the characteristics of modified substrates. In addition, the improvement in the membrane morphology (an increase in the length and number of finger‐like pores) provided a substrate with low tortuosity and structure parameters. Therefore, the pure water permeability increased from 79.9 LMH/bar for the control membrane to 372.1 LMH/bar for the membrane containing 20 wt.% of PSf‐g‐PMMA copolymer. Investigating the FO separation properties of TFC‐FO membranes showed an increase in water flux and selectivity due to an improvement in the morphology of the modified substrate with low structural parameters. The new TFC‐FO membranes have been optimized, and water flux has significantly improved. Compared with the control membrane, which did not have copolymer blending, the new membranes have a triply enhanced water flux of 17.1 LMH. In addition, the selectivity of these optimized membranes has improved when 1 M NaCl is used as the draw, and DI water is used as the feed in the FO mode.

Structure design and performance optimization of PVDF-CTFE nanofibrous composite nanofiltration membrane modified by C–Cl active site grafting

The substrate membrane plays a crucial role in determining the performance of composite nanofiltration membranes prepared by interfacial polymerization (IP). In this study, persistent hydrophilic modification of polyvinylidene fluoride-co-chlorotrifluoroethylene (PVDF-CTFE) was achieved by incorporating N-methylglucamine (N-MG) without altering the membrane's morphology or pore size. Moreover, thin-film nanofibrous composite (TFNC) nanofiltration membranes were prepared using the surfactant assembly regulated interfacial polymerization (SARIP) method with the modified PVDF-CTFE@N-MG nanofibrous membrane as the substrate. The effect of N-MG addition on the substrate membrane's hydrophilicity and the structure and performance of the polyamide (PA) separation layer was investigated. The results showed that the addition of N-MG significantly improved the hydrophilicity of the PVDF-CTFE nanofibrous membrane. The TFNC-5 membrane, prepared with the modified PVDF-CTFE@N-MG nanofibrous membrane as the substrate, exhibited permeability exceeding 13.5 L m−2 h−1·bar−1 for various dye solutions at 3 bar pressure, with rejection rates above 98 %. It also demonstrated excellent selective separation performance (separation factor for NaCl/Orange G reaching 97.38) and long-term operational stability. This work provides a method for the preparation of low-pressure, high-flux nanofiltration membranes, which is applicable to seawater desalination and dye wastewater treatment.

Effect of Ammonium Peroxydisulphate (APS) Addition on Polyaniline Nanofiber Microstructure in Interfacial Polymerization Method

Effect of Ammonium Peroxydisulphate (APS) Addition on Polyaniline Nanofiber Microstructure in Interfacial Polymerization Method

Exploring polyaniline nanofiber synthesis at vegetable oil-water interfaces for high-performance hybrid electrochemical capacitors

Polyaniline (PANI) nanofibers are synthesized at five different vegetable oil-water interfaces by a modified interfacial polymerization method. A series of syntheses is performed to study the effect of vegetable oil- water interfaces on the sizes, morphologies and corresponding electrochemical performances of resultant PANI nanofiber samples. Five PANI nanofiber samples are synthesized and the corresponding electrochemical performances as electrochemical capacitor (EC) electrodes are evaluated. It is observed that the PANI nanofiber sample prepared at water-sunflower oil interface, PANI5 possesses the lowest diameter and highest specific capacitance among all the prepared samples. Herein, we have fabricated an all-solid-state asymmetric electrochemical capacitor (AEC) of PANI5 and bio-derived chemically activated carbon (AC). The electrochemical measurements show that PANI5 and AC exhibits specific capacitance of 395 F g−1 and 240 F g−1 respectively at current density 1 A g−1. The fabricated PANI5//AC AEC exhibits areal capacitance of 70 mF cm−2 at current density of 1 mA cm−2. The energy density (Ed) and power density (Pd) of constructed AEC are found to be 19 µW h cm−2 and 696 µW cm−2, respectively. It gives the cyclic stability of 62 % retention of initial areal capacitance after completing 5000 galvanostatic charge-discharge cycles.

Anionic covalent organic framework membranes for the removal of per- and polyfluoroalkyl substances with enhanced selectivity

Nanofiltration (NF) is an effective technology for removing per- and polyfluoroalkyl substances (PFAS), a group of emerging pollutants. However, conventional NF membranes often reject high levels of minerals, leading to low salt/PFAS selectivity. Herein, we introduce the use of continuous ionic covalent organic framework (COF) membranes as a novel approach to achieve effective PFAS removal with high selectivity. Thin TpPa-SO3H COF selective membrane layers were fabricated on polymer supports using a scalable counter-diffusion interfacial polymerization (IP) method to form thin film composite (TFC) membranes. These membranes feature a highly negative surface charge and ordered pore channels with suitable pore sizes, leading to impressive PFAS rejection rates, with over 99 % rejection for perfluorooctanesulfonic acid (PFOS) and 90–95 % rejection for perfluorooctanoic acid (PFOA) and two short-chain PFAS. Moreover, the TpPa-SO3H membranes allowed the passage of scale-forming salts, enabling selective PFAS removal with a high salt/PFAS selectivity. Furthermore, these continuous ionic COF membranes exhibited a high water permeance of 19.9–37.5 LMH/bar, outperforming commercial membranes like NF270 and other lab-made membranes.

In-situ construction of covalent organic frameworks membrane via interfacial polymerization and crosslinking modification using trimesoyl chloride for organic solvent nanofiltration

Organic solvent nanofiltration (OSN) is a modern technology for separating and purifying organic solvents. It has the advantages of both low energy consumption and low environmental pollution. In this work, we utilized an oligomer triggered interfacial polymerization (OT-IP) method and followed by a post-IP modification using trimesoyl chloride (TMC) to synthesize a kind of covalent organic frameworks (COFs)/TMC membrane. This process involves pre-mixing both COFs monomers in a same organic solvent to form oligomers, followed by conducting an IP reaction at the interface between the organic solvent phase and an aqueous phase solution containing acetic acid as a catalyst. Subsequently, a surface modification is conducted using TMC n-hexane solution, which effectively manipulates the surface hydrophilicity, average size, solute rejection, solvent permeance and solvent resistance of the membrane. Afterward, crosslinking and solvent activation are performed to improve its solvent resistance and separation permeance. The optimized OSN membrane exhibits an ethanol permeance of 72.5 L m−2 h−1 MPa−1 with an RDB rejection of 98.4 %. Its surface roughness is as low as 3.4 nm. Furthermore, it has high permeance for both polar solvents (MeOH permeance of 176.7 L m−2 h−1 MPa−1) and weakly polar solvents (EtOAc permeance of 183.0 L m−2 h−1 MPa−1). Moreover, the optimized OSN membrane demonstrates excellent solvent resistance and excellent catalyst recovery performance. Therefore, this work presents a promising avenue for the application of COFs in OSN membranes.

Development of fluorosilicon bivalve isocyanate microcapsules for multifunctional coatings with excellent self-repairing properties, enhanced hydrophobicity, and corrosion protection properties

This study first self-made TMP-IPDI tetramer, and then prepared a fluorine-modified silicon dioxide double shell isocyanate type self-healing microcapsule (CBS-X/TMP-IPDI@PU@F-SiO2) using TMP-IPDI tetramer, fluorescent agent 4,4-bis (2-disulfonic acid sodium styrene) biphenyl (CBS-X) as the core material, polyurethane (PU) as the single shell, and fluorine modified silicon dioxide (F-SiO2) as the double shell using interfacial polymerisation method. Then, it was added to waterborne polyurethane (WPU) to prepare self-healing coatings and coatings. The chemical structure, microstructure, self-healing self detection, and mechanical properties of TMP-IPDI, CBS-X/TMP-IPDI@PU@F-SiO2, and composite coatings were characterized by infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), scanning electron microscopy (SEM), particle size analysis (PSA), X-ray electron spectroscopy (XPS) analysis, contact angle testing, tensile testing, electrochemical impedance testing, and Ultraviolet photograph. The results showed that the TMP-IPDI tetramer was successfully prepared. The average particle size of CBS-X/TMP-IPDI@PU@F-SiO2 prepared is 29 μm. The contact angle, tensile strength, low-frequency impedance and Nyquist curve radius of the repaired spots increased with the increase of the amount of CBS-X/TMP-IPDI@PU@F-SiO2 in WPUs; the increasing trend slowed down when the amount of CBS-X/TMP-IPDI@PU@F-SiO2 was >5 %. When the CBS-X/TMP-IPDI@PU@F-SiO2 dosage is 5 %, the WPU coating has good self-repair and self-detection performance. The stress before and after repair were 12.89 MPa and 20.11 MPa, respectively, with a repair rate of 80.3 %. The contact angle at the repair site can reach 100.8°, and the coating has good corrosion resistance. The microcapsules prepared based on fluorine-modified silica (F-SiO2) as the wall material have good self-healing performance for WPU coatings, achieving secondary protection of the repaired material.

Defect-Healed Carbon Nanomembranes for Enhanced Salt Separation: Scalable Synthesis and Performance.

Carbon nanomembranes (CNMs), with a high density of subnanometer channels, enable superior salt separation performance compared to conventional membranes. However, defects that occur during the synthesis and transfer processes impede their technical realization on a macroscopic scale. Here, we introduce a practical and scalable interfacial polymerization method to effectively heal defects while preserving the subnanometer pores within CNMs. The defect-healed freestanding CNMs show an exceptional performance in forward osmosis (FO), achieving a water flux of 105 L m-2 h-1 and a specific reverse salt flux of 0.1 g L-1 when measured with 1 M NaCl as draw solution. This water flux is 10 times higher than that of commercially available FO membranes, and the reverse salt flux is 70% lower. Through successful implementation of the defect-healing method and support optimization, we demonstrate the synthesis of fully functional, centimeter-scale CNM-based composite membranes showing high water permeance and a high salt rejection. Our defect-healing method presents a promising pathway to overcome limitations in CNM synthesis, advancing their potential for practical salt separation applications.

Preparation of self-standing ultra-thin three-dimensional covalent organic frameworks by interfacial polymerization for dye separation

Three-dimensional covalent organic frameworks (3D COFs) have garnered considerable attention in the adsorption of small molecules owing to their unique 3D pore structure and easily modifiable functional group sites. However, most 3D COFs exhibit lattice interpenetration, making the membrane fabrication process difficult. Most 3D COFs are prepared as powders using solvothermal methods, which severely limits their application in material separation. Therefore, self-supporting 3D COFs membranes were fabricated using room-temperature interfacial polymerization, a low-energy method. Traditional alkane/water interfacial polymerization methods have disadvantages such as poor water solubility of the monomer, volatile solvents, and low crystallinity. Herein, an imine-linked, self-standing, 3D COFs membrane with an ultrathin layer was engineered at the alkane/ionic liquid interface. Owing to the improved crystalline structure, which exposed a large number of imine-linked sites within a 3D pore channel, the constructed 3D COFs membrane exhibited a high Brunauer–Emmett–Teller surface area of 1061.4 m2·g−1 and high water flux of approximately 76 L·m−2 h−1 bar−1 and demonstrated excellent rejection rates of 97.76% and 95.36% for two cationic dyes, rhodamine B and methylene blue, respectively. The membrane exhibited high rejection rates after seven testing cycles. This study reveals the great potential of self-standing 3D COFs membranes as dye separation.

Sintesis polianilin (PANi) dengan metode polimerisasi interfasial sebagai bahan dasar pembuatan sensor gas amonia (NH3)

One of the main components in IoT-based devices is sensors. Polyaniline is a conductive polymer that has great potential to be developed as an active layer for chemical sensors because it has high sensitivity, is easy to synthesize and its electrical conductivity can be adjusted. This study aims to synthesize and characterize polyaniline using the interfacial polymerization method. In this study, polyaniline was synthesized by varying the aniline concentration of 2, 3, and 5 M, then its functional groups were characterized using FTIR and its conductivity and sensitivity were measured with an LCR meter. The result shows that polyaniline is in the form of emeraldine salt which is characterized by the formation of absorption bands at concentrations of 2, 3, and 5 M, respectively, 1,141.86 cm-1, 1,139 cm-1 and 1,139.93 cm-1. The highest conductivity was obtained at a concentration of 2 M, namely 4.9x10-5 and a sensitivity of 82.8% for an ammonia concentration of 100 ppm. So it can be concluded that the polyaniline obtained is a form of semiconducting emeraldine salt.

Study on bulletproof performance of functionalized fabrics modified by microcapsules

AbstractThe incorporation of microcapsule particles (MPs) into fabrics offers the potential to enhance both the friction between fabric yarns and the bulletproof impact performance. In this study, MPs were prepared using the interfacial polymerization method. Furthermore, an innovative modification of the AF fabric was achieved by introducing a silane coupling agent and MPs. This resulted in the development of a microcapsules‐aramid fibers (MPs‐AF) composite material exhibiting excellent protective performance. The characterization experiment demonstrated the successful adhesion of MPs to the AF fabric, forming a robust bond between the fiber and the particles. Importantly, the modification process did not have any adverse effects on the fiber structure. The study further investigated the ballistic performance and protection mechanism of the modified fabrics through mechanical performance tests and ballistic impact tests. The yarn pull‐out experiment revealed that the MPs‐AF composite material exhibited a significant increase in pull‐out force, with a remarkable improvement of 175.6% compared to AF fabric. In the ballistic impact experiments, the MPs‐AF composite material demonstrated a substantial increase in ballistic limit velocity, rising from 52 to 118 m/s when compared to the AF fabric. These findings highlight the potential application of the MPs‐AF composite material in the field of wearable protection.Highlights Fiber surface modification grafting reaction. A simple and novel solution impregnation method was used to prepare modified AF. Preparation of microcapsule particles by interfacial polymerization. Green new fiber bulletproof material. Chemical grafting produces strong chemical bonds to increase interfacial resistance.

Interfacial polymerization of self-standing ABC-stacking Covalent organic framework membranes for dye separation

Covalent organic framework (COF)-based membranes are burgeoning candidates for separation technologies owing to their well-ordered channel structures. However, it is still a significant challenge to obtain high-quality COF membranes with a mild and convenient preparation strategy. In this paper, we adopted a simple liquid-liquid interfacial polymerization method to manufacture a self-standing COF membrane with decent crystallinity at room temperature. Aldehyde monomer and catalyst were dissolved in water as the bottom layer and the amine monomer was dissolved in ethyl acetate as the top layer, and new COF membranes were subsequently obtained by interfacial polymerization in the two-phase interface. The synthetic conditions including precursor and catalyst dosage were further optimized, and thus-synthesized PDA-TAPB-ABC membrane displayed a stable rejection to MB of 97.57% with a high water permeance of up to 101. 32 L m−2h−1bar−1. Its dyes separation performance was much better than their AA-stacking counterpart. Moreover, the prepared membrane endowed favorable chemical stability and long-term durability.

Photo-modulated activation of organic bases enabling microencapsulation and on-demand reactivity

A method is developed for facile encapsulation of reactive organic bases with potential application for autonomous damage detection and self-healing polymers. Highly reactive chemicals such as bases and acids are challenging to encapsulate by traditional oil-water emulsion techniques due to unfavorable physical and chemical interactions. In this work, reactivity of the bases is temporarily masked with photo-removable protecting groups, and the resulting inactive payloads are encapsulated via an in situ emulsion-templated interfacial polymerization method. The encapsulated payloads are then activated to restore the organic bases via photo irradiation, either before or after being released from the core-shell carriers. The efficacy of the photo-activated capsules is demonstrated by a damage-triggered, pH-induced color change in polymeric coatings and by recovery of adhesive strength of a damaged interface. Given the wide range of potential photo-deprotection chemistries, this encapsulation scheme provides a simple but powerful method for storage and targeted delivery of a broad variety of reactive chemicals, promoting design of diverse autonomous functionalities in polymeric materials.

Preparation and thermal properties of nano-microcapsule and simulation heat storage application

The prevention of material leakage and improvement of thermal conductivity are very important for thermal energy storage application. In this work, nano-TiO2@n-docosane microcapsules were synthesized by the fine emulsion interface polymerization method using tetra-n-butyl titanate (TBT). This approach enhances the encapsulation rate and efficiency of phase change microcapsules. The microcapsules formation process was observed using a biological microscope. The diameter of the microcapsules decreased significantly with the increase of stirring rate. The phase transition temperature of the optimal microcapsules is 42.4 °C. The encapsulation rate and efficiency reach up to 90.7% and 91.0%, respectively. The average thermal conductivity of nano-TiO2@n-docosane microcapsules is 215% higher than that of n-docosane. SEM and infrared spectroscopy testing results confirm the successful coating of n-docosane by TiO2. Thermogravimetric analysis presents that TiO2 forms a shell, which reduces the leakage of n-docosane. The melting and solidification processes of n-docosane and nano-TiO2@n-docosane microcapsules were simulated numerically. In comparison to n-docosane, nano-TiO2@n-docosane microcapsules exhibit a 14.89% increase in peak storage power and a 12.47% increase in heat transfer coefficient during charging. Additionally, during discharging, these values rise by 3.23% and 6.46%, respectively. Nano-TiO2@n-docosane microcapsules enhance heat transfer and the charging/discharging process of phase change materials.

Hollow Fiber Membrane Modification by Interfacial Polymerization for Organic Solvent Nanofiltration

Hollow fiber (HF) organic solvent nanofiltration (OSN) membranes have recently attracted significant interest in the field of membrane technology. Their popularity stems from comparative advantages, such as high packing density, fouling resistance, and easier scalability for larger applications, unlike flat-sheet/spiral-wound OSN membranes, which may present challenges in these aspects. The combination of interfacial polymerization (IP) and HF configuration has opened up new opportunities for developing advanced membranes with enhanced separation performance that can be tailored for various OSN applications. The objective of this review is to discuss the latest advancements in developing thin film composite (TFC) HF membranes, with a focus on the IP method. Novel materials and processes are discussed in detail, emphasizing the fabrication of greener, interfacially polymerized HF OSN membranes. In addition, the commercial viability and limitations of TFC HF membranes are highlighted, providing perspectives on future research directions.

TFN nanofiltration membrane incorporating ZIF-8@MXene for efficient removal ReO4- from simulated nuclear-contaminated wastewater

In an effort to explore the potential application prospects of membrane separation technology in treating nuclear-contaminated wastewater, a TFN nanofiltration membrane incorporating the ZIF-8@Ti3C2Tx nanocomposite was successfully synthesized using the interfacial polymerization method. This involved doping the microemulsion of ZIF-8@Ti3C2Tx into the aqueous (organic) phase. The morphology and structure of ZIF-8@MXene nanocomposites and TFN nanofiltration membranes were characterized. The selective removal of ReO4- from simulated radioactive wastewater using the TFN nanofiltration membrane was evaluated. The results indicated that the ZIF-8@Ti3C2Tx composite, uniformly dispersed in the polymer, effectively enhanced the pore structure and polarity of the nanofiltration membrane, thereby improving its permeability. The electronegativity of ZIF-8@Ti3C2Tx also enhanced the negative charge on the surface of the polymer membrane, significantly improving the membrane’s performance in rejecting ReO4- while maintaining a low retention rate for Na+. This design facilitates the efficient selection of ReO4- from high-salinity wastewater. In addition, the layer spacing of Ti3C2Tx further improved the screening of ReO4- and Na+. However, when 0.75 g·L−1 of microemulsion was added, it became challenging to disperse the microemulsion completely in the organic phase. This led to the agglomeration of composites in the nanofiltration membrane, weakening both flux and selectivity. Optimal performance was achieved with a microemulsion doping amount of 0.5 g·L−1, resulting in the nanofiltration membrane M-O-1 exhibiting the best performance (Jp = 41.92 L·m2·h−1 and R(ReO4-) = 65.81%). Even at a high salt concentration (20 g·L−1), the M-O-1 membrane retained approximately 55% of pollutants after continuous operation for 5 h, indicating that the TFN nanofiltration membrane containing ZIF-8@Ti3C2Tx holds significant promise for selectively extracting 99Tc from wastewater with a high salt content.

Decoupling synthesis and crystallization of covalent organic frameworks (COFs) for more crystalline layer targeting high efficiency dye separation

Covalent organic frameworks (COFs) are crystalline porous materials composed of organic building blocks linked by covalent bonds, which have attracted great attention for membrane–based separation applications. However, fabrication of COF membranes with high quality and performance remains a challenge, especially for the β–ketoenamine linked COFs. In the conventional IP methods, the synthesis process (the Schiff–base reaction of the monomers and the tautomerism of the oligomers) and the crystallization process (the self–assembly of the oligomers) of the COFs materials occur simultaneously on the surface of the support membrane, which can result in low crystallinity, high defect density, and poor separation performance of the COF layer. In this study, a novel strategy for fabricating large-area, defect–free COFs composite membranes by interfacial polymerization (IP) was presented to overcome this problem. By incorporating both the amine and aldehyde monomers in one organic phase, and dissolving organic acid catalyst in another phase (the water), the synthesis process mostly take place in the bulk of the organic phase, while the crystallization occurs on the surface of the support membrane under the influence of the organic acid catalyst. This strategy effectively decoupled the synthesis process with the crystallization, providing a stable growth region for crystalline layer, ultimately leading to the formation of a thin, defect–free and highly ordered COF layer on the support membrane. The strategy was demonstrate by synthesis of triformylphloroglucinol phenylenediamine (TpPa)–Ⅱ/Poly(m–phenylene isophthalaminde) (PMIA) composite membrane. We characterize the structure and morphology of the TpPa–Ⅱ/PMIA composite membrane by various analytical techniques to verify our hypothesis, and evaluate its separation performance using pure water permeance and dyes retention rate as indicators. The results show that the TpPa–Ⅱ/PMIA composite membrane has an 80 nm thick top-layer with regular COF structure and orderly pores. It exhibits an excellent dye separation performance, with a (pure water permeance) PWP of 105.6 L·m−2·h−1·bar−1 and CR rejection of 99.2 %, which surpasses most of the TpPa–type COFs composite membranes reported in literature, as well as the reference (TpPa–I/PMIA membrane) in this work. Moreover, the TpPa–Ⅱ/PMIA composite membrane maintains both its performance and structural stability during a 240–hour cross–flow filtration of the dye solution, demonstrating its excellent potential in the dye wastewater treatment.