Screening method of coordination regulation mixed matrix membrane based on molecular simulation

Abstract

The invention belongs to the technical field of gas separation membranes, and particularly relates to a molecular simulation-based screening method of a coordination regulation mixed matrix membrane. The method is combined with a molecular simulation technology and is used for quantitatively evaluating the interface compatibility of the mixed matrix membrane and reasonably screening and designing a coordination active additive so as to synergistically optimize the interface structure and the gas separation performance. According to the method disclosed by the invention, a new method for accurate prediction and rational design from a microscopic molecular structure to macroscopic membrane performance is realized, and the method can be used for guiding efficient development of high-performance MMMs.

Description

Technical Field

[0001] This invention belongs to the field of gas separation membrane technology, and specifically relates to a screening method for coordination-regulated mixed matrix membranes based on molecular simulation. Background Technology

[0002] C3H6 is a crucial basic raw material in the petrochemical industry, and it often coexists with C3H8 during its production. Due to the extreme similarity in molecular size and physical properties between the two, the separation of C3H6 / C3H8 has become a highly energy-intensive and challenging task in industry. Compared with traditional energy-intensive processes such as cryogenic distillation, membrane separation technology is considered a promising alternative due to its advantages of low energy consumption and ease of operation.

[0003] Hybrid matrix membranes (MMMs), a novel type of composite membrane material composed of a continuous polymer matrix and a dispersed porous packing, aim to synergistically combine the processability of polymers with the high selectivity of packing, representing a key technological pathway for achieving efficient and energy-saving gas separation. Among them, MMMs composed of ZIF-8 and PIM-1 have shown great application potential in critical industrial gas separation systems such as C3H6 / C3H8.

[0004] However, the inherent differences in physicochemical properties between MOFs and polymers make it easy for non-ideal structures to form at their interfaces, mainly manifested in the following three types of defects: First, interfacial voids, stemming from weak interactions between MOF and polymer chains and excessively rigid polymer chains, forming non-selective interfacial pores that severely impair membrane selectivity; second, polymer rigidification, caused by excessively strong interactions between MOF and polymer chains, leading to restricted polymer chain movement and excessive stacking in the interfacial region, significantly reducing membrane permeability; and third, pore blockage, caused by polymer chains or solvent molecules intruding into MOF pores during the preparation process, hindering gas transport. These interfacial defects have become the core bottleneck restricting MMMs from achieving their theoretical separation performance and moving towards large-scale industrial applications.

[0005] To improve interfacial compatibility, existing technologies mainly revolve around two strategies: covalent modification and non-covalent modification. While covalent modification can significantly enhance interfacial interactions, it typically involves complex surface functionalization steps and harsh reaction conditions, making the process cumbersome and costly, and potentially damaging the inherent porosity of the filler. Non-covalent modification, such as introducing π-π interactions, hydrogen bonds, or electrostatic interactions, operates under milder conditions, but its interaction strength is relatively weak, resulting in limited improvement. Furthermore, it often depends on specific functional groups, lacking universality.

[0006] In recent years, the introduction of third-component additives with coordination capabilities has been considered a promising interface engineering strategy. Coordination bonds possess a suitable balance of strength and directionality, effectively enhancing interfacial adhesion without excessively increasing process complexity. However, research in this field still heavily relies on experimental trial-and-error methods. Faced with a vast array of potential additives, their compatibility with specific MOF / polymer combinations, their microscopic arrangement behavior at the interface, and their regulatory mechanisms on final separation performance remain unclear. This blind screening approach is inefficient, costly, and fails to elucidate structure-activity relationships at the molecular level, severely hindering the targeted development of high-performance MMMs.

[0007] Molecular simulation and density functional theory have become powerful tools for studying the microstructure and separation mechanisms of membrane materials at the atomic / molecular scale. However, current research mainly focuses on the "post-hoc interpretation" and mechanistic analysis of known, single MMM systems. There is no report of a universal methodology that integrates multi-scale molecular simulation with "quantitative evaluation, rational pre-screening, and performance prediction," and can proactively guide the design and screening of MMM interface additives.

[0008] Specifically, how to accurately quantify the quality of interface compatibility through simulation, how to quickly predict the coordination feasibility of additives with MOFs and their gas selectivity, and how to accurately predict the comprehensive impact of additive introduction on interface structure and macroscopic separation performance are technical problems that urgently need to be solved but have not yet been overcome in this field. Summary of the Invention

[0009] The purpose of this invention is to provide a screening method for coordination-regulated hybrid matrix membranes (MMMs) based on molecular simulation. By organically combining multi-scale molecular simulations, a closed-loop design process from molecular recognition to performance prediction is constructed.

[0010] This invention aims to contribute from one or more of the following perspectives:

[0011] 1) Overcome the interface defects caused by poor compatibility between fillers and polymer matrix in MMMs, especially interface voids, polymer rigidification and pore blockage.

[0012] 2) To break free from the current reliance on trial-and-error methods in screening interface-modulated additives, and provide a universal method for rationally, accurately, and efficiently screening the optimal additives. How can we accurately predict the final interfacial microstructure and gas separation performance of MMMs at the molecular level before their preparation, thus achieving "directional design" of materials?

[0013] 3) Reveal the intrinsic structure-activity relationship between the molecular structure of additives, the microstructure of the interface, and the macroscopic separation performance, providing theoretical guidance for the design of a new generation of high-performance MMMs.

[0014] The technical solution adopted in this invention is as follows:

[0015] A screening method for coordination-regulated hybrid matrix membranes based on molecular simulation includes the following steps:

[0016] 1) Benchmark evaluation: Construct a benchmark mixed matrix membrane molecular model without additives, obtain its equilibrium structure through molecular dynamics simulation, which is called the benchmark MMMs model, and calculate its benchmark interface characteristic parameters and benchmark gas separation performance parameters.

[0017] 2) Necessity judgment: Based on the baseline interface characteristic parameters in step 1), determine whether the interface compatibility of the baseline MMMs model needs to be optimized; if the baseline interface characteristic parameters do not meet the preset conditions, then proceed with the subsequent steps to optimize.

[0018] 3) Additive pre-screening: Using DFT calculations, coordination active additives are pre-screened;

[0019] 4) Quantification of interface regulation effect: Construct a mixed matrix membrane model containing pre-screened additives, perform molecular dynamics simulation to obtain its equilibrium structure, which is called the MMMs model to be evaluated, and calculate the change of its interface characteristic parameters relative to the baseline interface characteristic parameters in step 1).

[0020] 5) Separation performance prediction: Based on the MMMs model to be evaluated in step 4), the gas separation performance parameters are predicted through gas adsorption and diffusion simulation, and the relative change value of the gas separation performance parameters relative to the baseline gas separation performance parameters described in step 1) is calculated.

[0021] 6) Comprehensive optimization: Combining steps 4) and 5), select the final additive from the pre-screened additives that can synergistically optimize interfacial compatibility and gas separation performance.

[0022] Furthermore, the interface characteristic parameters mentioned in step 1) are one or more of the following parameters: interfacial bonding energy (ΔE) binding Interface length (L) interface ), free volume (V) f ), porosity (Φ).

[0023] It should be noted that in step 1), the baseline gas separation performance parameters can be omitted initially and calculated later in step 2) when optimization is deemed necessary. For ease of description, this calculation step is included in step 1).

[0024] In step 2), the statement that the reference interface characteristic parameters do not meet the preset conditions means that three or more of the interface characteristic parameters do not meet the following threshold conditions: absolute value of interface binding energy > 750.00 kcal / mol, interface length Free volume <70cm 3 / g, porosity <60%.

[0025] In step 3), the pre-screened coordination active additives must meet the following conditions: the absolute value of the binding energy between the additive and the MOF filler is greater than the absolute value of the binding energy between the polymer and the MOF filler; and the absolute value of the binding energy of the additive to the target gas molecules is greater than the absolute value of the binding energy to the non-target gas molecules.

[0026] In step 5), the gas adsorption simulation is a giant canonical Monte Carlo simulation (GCMC), and the gas diffusion simulation is based on equilibrium molecular dynamics simulation (EMD) to calculate the mean square displacement (MSD) of gas molecules; the gas separation performance parameters are permeability (P) and selectivity (α).

[0027] In step 6), the principle for selecting the final additive that can synergistically optimize interfacial compatibility and gas separation performance is: the interfacial binding energy (ΔE) obtained in step 4). binding ), free volume (V) f The changes in porosity (Φ), permeability (P) calculated in step 5) are all less than 0, the percentage change in permeability P is greater than 10%, and the percentage change in selectivity is greater than 1.

[0028] The molecular dynamics simulation described in steps 1), 4), and 5) of the method of the present invention uses a universal amber force field (GAFF) and includes a multi-step relaxation process in which the polymer matrix is ​​compressed using a MOF as a piston under the NPT ensemble.

[0029] In the method of the present invention, the MOF filler is preferably ZIF-8, and the polymer matrix is ​​an inherently microporous polymer, preferably PIM-1.

[0030] The candidate additives include ionic liquids (ILs), metal complexes, or functional polymers; preferably, the IL is [Pmim][TF2N], the metal complex is silver tris(pyrazolylacetic acid) (AgPZ), and the functional polymer is OPBI.

[0031] The gas separation parameters are preferably those used for the separation of propylene (C3H6) / propane (C3H8).

[0032] This invention is basically divided into the following stages:

[0033] a) Benchmark Assessment and Necessity Determination: Construct a baseline all-atom model of MMMs without additives, obtain its equilibrium configuration through molecular dynamics simulations, and calculate its baseline interfacial characteristic parameters (such as interfacial binding energy, interfacial length, free volume, and porosity) and baseline gas separation performance parameters (such as permeability and selectivity). Based on the aforementioned baseline interfacial characteristic parameters, determine its interfacial compatibility level according to the compliance with threshold conditions. If significant defects exist, initiate the additive screening process.

[0034] b) Rational pre-screening of additives: Using DFT calculations, the binding energy of candidate additives with the target MOF filler is evaluated. Preferably, the binding energy with the target gas molecules is also evaluated. Based on predetermined screening criteria, potential additives are quickly identified from the candidate library, i.e., the binding energy between the additive and the MOF is stronger than that between the polymer and the MOF, and the additive exhibits better adsorption affinity for the target gas than for the impurity gas.

[0035] c) Quantitative prediction of interfacial regulation effects and separation performance: Pre-screened additives are introduced into a baseline model to construct an additive-regulated MMMs model. Molecular dynamics simulations are used to quantitatively calculate the changes in interfacial characteristic parameters relative to the baseline interfacial characteristic parameters (e.g., the change in interfacial binding energy Δ). ΔEbinding Free volume change ΔV f (Porosity change rate ΔΦ, etc.). Based on this equilibrium structure, the gas adsorption and diffusion behavior is further predicted through GCMC and equilibrium molecular dynamics simulations, and the relative changes of gas separation performance parameters (permeability, selectivity) relative to the baseline values ​​are calculated.

[0036] d) Comprehensive optimization and output: Taking into account the obtained interface structure optimization index and gas separation performance improvement index, the optimal coordination active additive that can synergistically optimize interface compatibility and separation performance is selected through weighted judgment or visualization analysis (such as radar chart) as the target molecule for experimental synthesis.

[0037] This invention establishes for the first time a rational design bridge from the microscopic molecular level to macroscopic separation performance, overcoming the blindness of traditional trial-and-error methods and providing a universal solution for the precise and efficient development of high-performance MMMs. It has the following beneficial effects:

[0038] 1) Foresight and accuracy: It transforms molecular simulation from a "post-analysis" tool to a "pre-design" guide, enabling accurate prediction of final performance before experiments are conducted, realizing "on-demand design" of MMMs, greatly shortening the R&D cycle and reducing R&D costs.

[0039] 2) Rationalization and efficiency: Pre-screening of additives through DFT calculations avoids time-consuming and laborious experimental exploration on a large number of invalid candidate molecules, transforming the screening process from "finding a needle in a haystack" to "targeted screening", resulting in an order-of-magnitude improvement in efficiency.

[0040] 3) Quantification and In-depth Insight: By calculating the changes in interface parameters and gas separation performance parameters, a precise and quantitative assessment of the additive's regulatory effect is achieved. More importantly, this method can profoundly reveal the intrinsic structure-property relationship between "additive structure → interface microstructure → macroscopic separation performance" at the molecular level, providing a solid theoretical foundation for guiding the development of new materials.

[0041] 4) Universality and strong adaptability: The methodological framework established by this invention does not depend on specific MOF, polymer or additive types, and can be widely applied to different gas separation systems, with strong versatility and scalability.

[0042] 5) Collaborative optimization capability: Through a comprehensive evaluation mechanism, additives that can simultaneously achieve strong interfacial adhesion (reducing defects) and high separation performance (high permeability and high selectivity) can be successfully screened, solving the industry problem that traditional methods cannot achieve both simultaneously.

[0043] In general, this invention provides a universal method that combines molecular simulation technology to quantitatively evaluate the interfacial compatibility of MMMs and rationally screen and design coordination active additives to synergistically optimize interfacial structure and gas separation performance. This new method realizes accurate prediction and rational design from microscopic molecular structure to macroscopic membrane performance and can be used to guide the efficient development of high-performance MMMs. Attached Figure Description

[0044] Figure 1 This is a flowchart of the screening method for coordination-regulated hybrid matrix membranes based on molecular simulation according to the present invention;

[0045] Figure 2 This is a schematic diagram of the molecular model involved in the embodiments;

[0046] Figure 3 The optimized configuration and energy diagram of the additive's binding with ZIF-8 and gas molecules were obtained through DFT calculations.

[0047] Figure 4 This is a quantitative comparison chart of the effects of additives on the microstructure of the ZIF-8 / PIM-1 interface;

[0048] Figure 5 This is a quantitative comparison chart of the effects of additives on the gas separation performance of ZIF-8 / PIM-1;

[0049] Figure 6This is a schematic diagram of the comprehensive performance evaluation of additives based on radar charts. Detailed Implementation

[0050] The technical solution of the present invention is illustrated below with specific embodiments, but the scope of protection of the present invention is not limited thereto:

[0051] This embodiment uses C3H6 / C3H8 separation as an application scenario to fully demonstrate the entire process of regulating interfacial coordination in ZIF-8 / PIM-1 hybrid matrix membranes. The overall process flow can be found in [link to documentation]. Figure 1 The flowchart shown.

[0052] (1) Benchmark system construction and quantitative compatibility assessment

[0053] The core objective of this step is to establish an objective evaluation benchmark and quantify the compatibility of the initial interface.

[0054] The specific steps are as follows:

[0055] First, based on Figure 2 The molecular structures of ZIF-8 and PIM-1 shown in Figure a were used to construct an initial ZIF-8 / PIM-1 baseline hybrid matrix membrane molecular model. The ZIF-8 model used the

[011] crystal plane, and its surface was modified with -OH and -H groups to simulate a real environment. The amorphous cell model of polymer PIM-1 was built using the Amorphous Cell module of Materials Studio. All atomic force field parameters and charges were matched to a universal GAFF to ensure force field compatibility.

[0056] Subsequently, an improved "21-step molecular dynamics relaxation method" was used to construct the initial interface: two ZIF-8 boxes were placed on the upper and lower sides of the PIM-1 polymer matrix, with the bottom ZIF-8 fixed and the top ZIF-8 acting as a "piston," and the system was cyclically compressed and relaxed under the NPT ensemble. Then, the top ZIF-8 was fixed again, and the bottom ZIF-8 was used as a piston for cyclic compression. This process aimed to simulate the actual arrangement and adsorption process of polymer chains on the filler surface during experimental preparation. Finally, the system underwent MD simulations for more than 1 ns under the NVT ensemble to obtain a fully balanced baseline MMM structure (its final configuration overview is shown in...). Figure 2 (c right side) All of the above molecular dynamics simulations were performed in LAMMPS software.

[0057] To quantitatively assess the compatibility of this benchmark interface, this invention performs a series of calculations on the obtained equilibrium structure, i.e., the benchmark MMM molecular model, and obtains that the interfacial binding energy of this benchmark MMM is -621.97 kcal / mol, and the interfacial length is... Its free volume is as high as 69.66 cm³. 3 / g, porosity reaches 61.41%. The above parameters are compared with the set threshold conditions (interface length). Interfacial binding energy absolute value >750.00 kcal / mol, free volume <70 cm³ 3 A comparison was made between the baseline MMM and the data (with a porosity of <60%), revealing that three characteristic parameters at the interface did not meet the threshold conditions. This indicates that the baseline MMM exhibits "interfacial voids" and "C3H6 / C3H8" separation defects. The above process quantitatively demonstrates the poor interfacial compatibility of this baseline system, necessitating the introduction of a third component for regulation and optimization. This conclusion is consistent with... Figure 1 The first 'No' branch in the flowchart corresponds directly to this.

[0058] (2) Rational pre-screening of coordination active additives

[0059] After confirming the necessity of interface optimization, this invention shifted to the rational pre-screening of additives to avoid the high cost and low efficiency of the traditional "trial and error method".

[0060] This invention selects three candidate additives with distinct structures but all possessing coordination potential: an ionic liquid ([Pmim][TF2N]), a silver-based complex (AgPZ), and a polymer (OPBI), the molecular structures of which are shown below. Figure 2 b. Using DFT calculations, the coordination feasibility of the above candidate additives with ZIF-8 was first evaluated. For example... Figure 3 As shown in a-3d, the binding energy (ΔE) is calculated. binding It was found that the binding energies of all three were much negative than those of PIM-1 and ZIF-8 (-39.01 kcal / mol, corresponding to...). Figure 3 d) The binding strength order is: AgPZ (-73.85 kcal / mol, corresponding to Figure 3 c)>[Pmim][TF2N](-52.26kcal / mol, corresponding to Figure 3 a)>OPBI(-42.96kcal / mol, corresponding to Figure 3 b). The absolute values ​​of the binding energy of all three are greater than the absolute value of the binding energy between the polymer and the MOF filler. This result theoretically confirms that all three can be stabilized on the ZIF-8 surface through coordination.

[0061] Further evaluation was conducted on the additive's differentiated adsorption potential for the target gas (C3H6) and impurity gas (C3H8). For example... Figure 3 As shown in e-3f and Table 1 (Binding energies calculated at different interaction sites between the three coordination additives and C3H6 / C3H8 in DFT), the absolute values ​​of the binding energies of the additives for the target gas (propylene) are all greater than those for non-target gases. Furthermore, DFT calculations reveal that AgPZ exhibits significant specific adsorption for propylene, with the binding energy difference (ΔE) at different adsorption sites being particularly high.binding(C3H6) -ΔE binding(C3H8) The maximum gas selectivity can reach -5.13 kcal / mol, indicating its great potential as a selectivity promoter. While IL and OPBI exhibit relatively weaker gas selectivity, the combined DFT data demonstrates that all three coordination additives passed the required standards. Figure 1 The pre-screening stages. The above steps precisely correspond to... Figure 1 The "density functional theory analysis" step in the process provides a scientific basis and target molecules for subsequent atomic simulations.

[0062] Table 1

[0063]

[0064] (3) Multiscale quantitative prediction of the regulatory effect of additives

[0065] This step is the core of the quantitative evaluation of this invention, aiming to predict the comprehensive impact of additives on the interfacial microstructure and macroscopic separation performance.

[0066] The pre-screened additives were introduced into the baseline MMM model at an equivalent mass loading rate (the three additives were added at the same mass ratio to ensure that the amount (mass) of the three additives was the same and to ensure the accuracy of the study). The "21-step molecular dynamics relaxation method" from step 1) was applied again to ensure that a thermodynamically stable additive-interface composite structure was obtained (see the final model snapshot). Figure 2 (c, left side). Subsequently, a comprehensive quantitative analysis was conducted on the balanced system.

[0067] At the interface microstructure level (see...) Figure 4 Calculate the changes in key parameters:

[0068] Interface binding energy change (Δ ΔEbinding ):like Figure 4 As shown in a, [Pmim][TF2N] has the most significant enhancement effect on interfacial binding (-364.61 kcal / mol), followed by OPBI (-309.84 kcal / mol), while AgPZ is relatively weak (-156.89 kcal / mol).

[0069] Free volume and porosity variation (ΔV) f ,ΔΦ): such as Figure 4 As shown in b, [Pmim][TF2N] can fill interfacial voids most effectively, resulting in the largest reduction in free volume and porosity.

[0070] In terms of gas separation performance (see...) Figure 5 Prediction is made through multiphysics simulation:

[0071] First, the equilibrium adsorption capacities of propylene and propane under 300 K and 5 bar conditions were calculated using GCMC.

[0072] Subsequently, based on the adsorption equilibrium configuration, equilibrium molecular dynamics simulations were performed. By calculating the mean square displacement of gas molecules and fitting the curves, the self-diffusion coefficient of the gas was obtained.

[0073] Finally, based on the dissolution-diffusion model, the adsorption coefficient is multiplied by the diffusion coefficient (P = S * D) to obtain the gas permeability, and the ideal selectivity of C3H6 / C3H8 is calculated. Figure 5 As shown in a and 5b, the performance prediction results show a completely different trend from the interface structure regulation: AgPZ can significantly increase propylene permeability by about 19.9% ​​and greatly improve selectivity by about 131.5%; while [Pmim][TF2N], which has the best interface compatibility improvement, actually leads to a decrease in both permeability and selectivity.

[0074] (4) Comprehensive performance evaluation and optimal additive output

[0075] The foregoing steps demonstrate that improvements in interface compatibility and separation performance are not always positively correlated. Therefore, this invention introduces a radar chart-based comprehensive evaluation method to achieve synergistic optimization.

[0076] like Figure 6 As shown, the four key indicators representing interface compatibility, namely "enhanced interface binding energy" and "reduced free volume", as well as the four indicators representing separation performance, namely "increased propylene permeability" and "increased C3H6 / C3H8 selectivity", are normalized and integrated into a single radar chart for visual analysis.

[0077] The radar chart of [Pmim][TF2N] shows the largest coverage area in terms of interface compatibility metrics, but a significant shrinkage in performance metrics, indicating that it is an "over-compatibility" strategy that sacrifices the membrane's transmission channels.

[0078] The radar chart of AgPZ exhibits a unique morphology: it covers the largest area in terms of separation performance indicators, while also showing a moderately enhanced interfacial binding energy. This indicates that while effectively enhancing interfacial interactions, AgPZ's unique rigid structure and gas affinity create and preserve pathways favorable for the selective transport of propylene.

[0079] OPBI's radar chart features fall somewhere in between.

[0080] according to Figure 6Considering the comprehensive evaluation conditions of the radar chart, neither [Pmim][TF2N] nor OPBI were satisfied, failing to achieve effective control. The AgPZ control model, however, demonstrated superior performance in improving gas separation selectivity and satisfied all radar evaluation conditions, thus being identified as the optimal coordination control additive in this embodiment. This decision-making process and conclusion output fully realize... Figure 1 The closed-loop design screening process.

[0081] This embodiment fully verifies the effectiveness of the method described in this invention. Through the organic combination and quantitative evaluation of multi-scale molecular simulations, this invention not only successfully predicted the regulatory behavior of different additives, but also rationally screened out the optimal additive AgPZ that can synergistically optimize interface and gas separation performance.

[0082] To further verify the reliability of the theory, experiments on the separation of C3H6 / C3H8 using the ZIF-8@AgPZ / PIM-1 mixed matrix membrane were carried out in actual preparation research. The results showed that compared with the mixed matrix membrane without additives, the gas permeability and selectivity of the composite membrane were significantly improved, and the performance change trend was highly consistent with the theoretical prediction of the present invention, which fully confirmed the theoretical reliability of the present invention.

[0083] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions, obvious modifications, or reasonable developments based on the concept of the present invention made by those skilled in the art within the scope of the technical solutions and principles disclosed in the present invention, as long as they are covered within the scope of the claims of the present invention, shall be deemed to fall within the scope of protection of the present invention.

Claims

1. A screening method for coordination-regulated hybrid matrix membranes based on molecular simulation, characterized in that, Includes the following steps: 1) Benchmark evaluation: Construct a benchmark mixed matrix membrane molecular model without additives, obtain its equilibrium structure through molecular dynamics simulation, which is called the benchmark MMMs model, and calculate its benchmark interface characteristic parameters and benchmark gas separation performance parameters. 2) Necessity judgment: Based on the baseline interface characteristic parameters in step 1), determine whether the interface compatibility of the baseline MMMs model needs to be optimized; If the baseline interface characteristic parameters do not meet the preset conditions, proceed with the next steps; 3) Additive pre-screening: Using DFT calculations, coordination-active additives are pre-screened; 4) Quantification of interface regulation effect: Construct a mixed matrix membrane model containing pre-screened additives, perform molecular dynamics simulation to obtain its equilibrium structure, which is called the MMMs model to be evaluated, and calculate the change of its interface characteristic parameters relative to the baseline interface characteristic parameters in step 1). 5) Separation performance prediction: Based on the MMMs model to be evaluated in step 4), the gas separation performance parameters are predicted through gas adsorption and diffusion simulation, and the relative change value of the gas separation performance parameters relative to the baseline gas separation performance parameters described in step 1) is calculated. 6) Comprehensive optimization: Combining steps 4) and 5), select the final additive from the pre-screened additives that can synergistically optimize interfacial compatibility and gas separation performance.

2. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, The interface characteristic parameters are one or more of the following parameters: interfacial bonding energy (ΔE) binding Interface length (L) interface ), free volume (V) f ), porosity (Φ).

3. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 2, characterized in that, If three or more of the interface characteristic parameters do not meet the following threshold conditions, the interface is deemed not to meet the preset conditions: interface length < 11.00 Å, absolute value of interface binding energy > 750.00 kcal / mol, and free volume < 70 cm³. 3 / g, porosity <60%.

4. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, In step 3), the pre-screened coordination active additives must meet the following conditions: the absolute value of the binding energy between the additive and the MOF filler is greater than the absolute value of the binding energy between the polymer and the MOF filler; and the absolute value of the binding energy of the additive to the target gas molecules is greater than the absolute value of the binding energy to the non-target gas molecules.

5. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, The molecular dynamics simulation employs a universal amber force field (GAFF) and includes a multi-step relaxation process in which the polymer matrix is ​​compressed using a MOF as a piston under the NPT ensemble.

6. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, In step 5), the gas adsorption simulation is a giant canonical Monte Carlo simulation (GCMC), and the gas diffusion simulation is based on equilibrium molecular dynamics simulation (EMD) to calculate the mean square displacement (MSD) of gas molecules; the gas separation performance parameters are permeability (P) and selectivity (α).

7. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, In step 6), the principle for selecting the final additive that can synergistically optimize interfacial compatibility and gas separation performance is: the interfacial binding energy (ΔE) obtained in step 4). binding ), free volume (V) f The changes in the three parameters (porosity (Φ)) are all less than 0, and the percentage change in permeability P calculated in step 5) is greater than 10%, and the percentage change in selectivity is greater than 1.

8. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in any one of claims 1-7, characterized in that, The MOF filler is ZIF-8, and the polymer matrix is ​​an inherently microporous polymer.

9. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 7, characterized in that, The candidate additives include ionic liquids (ILs), metal complexes, or functional polymers. Preferably, the IL is [Pmim][TF2N], the metal complex is tris(pyrazoleacetic acid)silver (AgPZ), and the functional polymer is OPBI.

10. The screening method for coordination-regulated hybrid matrix membranes based on molecular simulation as described in claim 1, characterized in that, The gas separation parameters are those used for propylene / propane separation.

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