A high-throughput simulation calculation method for polyurethane resin viscosity

Abstract

The present invention discloses a high-throughput simulation calculation method for polyurethane resin viscosity, comprising the following steps: (1) selecting a hydroxyl compound and an isocyanate compound, and determining the molar ratio of the hydroxyl group to the isocyanate group; (2) establishing a polyurethane molecular chain according to the molar ratio of the hydroxyl group to the isocyanate group; (3) filling a unit cell with the polyurethane molecular chain and solvent molecules to construct a polyurethane model; (4) first performing a force field distribution on the polyurethane model, and then performing geometric optimization on the polyurethane model with the force field distribution; (5) performing molecular dynamics simulation calculation on the optimized polyurethane model to achieve equilibrium; and (6) calculating the viscosity of the polyurethane model based on the dynamics calculation. The high-throughput simulation calculation method for polyurethane resin viscosity provided by the present invention can simultaneously perform viscosity calculations on multiple polyurethane structural models at one time, thereby reducing the heavy experimental workload and significantly lowering the experimental cost.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer resins, and in particular to a high-throughput simulation calculation method for polyurethane resin viscosity. Background Art

[0002] Polyurethane is a polymer with urethane chain segments obtained by the reaction of isocyanate and a polyhydroxy compound. Due to the presence of urethane bond structures in the molecular chain of polyurethane resin, there is strong hydrogen bonding between polyurethane molecules, which also leads to the high viscosity of polyurethane resin. High viscosity will bring many inconveniences to the operating process. Therefore, when using it, it is necessary to select polyurethane resins with corresponding structures and viscosities. At present, due to the wide variety of polyurethane resins and large structural differences, the study of the correspondence between polyurethane structure and viscosity is mainly limited to experimental analysis. However, this method requires the use of raw materials to synthesize polyurethane resins and then conduct testing. The raw material cost is high, the experiment is time-consuming, and the workload is heavy. This will consume a lot of manpower and material resources, and the research efficiency is low. Summary of the Invention

[0003] In view of this, the present invention provides a high-throughput simulation calculation method for polyurethane resin viscosity to solve the above-mentioned problems.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A high-throughput simulation calculation method for polyurethane resin viscosity comprises the following steps:

[0006] (1) selecting a hydroxyl compound and an isocyanate compound, and determining a molar ratio of a hydroxyl group to an isocyanate group in the hydroxyl compound and the isocyanate compound;

[0007] (2) building a polyurethane molecular chain using the 3D Atomistic component of Materials Studio based on the molar ratio of the hydroxyl group to the isocyanate group in the hydroxyl compound and the isocyanate compound in step (1);

[0008] (3) Using the Amorphous Cell module in Materials Studio, the unit cell is filled with the polyurethane molecular chains and solvent molecules in step (2) to construct a polyurethane model;

[0009] (4) Importing the polyurethane model in step (3) into the LAMMPS module of the Matcloud+ material cloud computing platform, first performing force field distribution on the polyurethane model, and then performing geometric optimization on the polyurethane model with the force field distribution to obtain the optimized polyurethane model;

[0010] (5) performing molecular dynamics simulation calculations on the polyurethane model optimized in step (4) to allow the system to reach an equilibrium state;

[0011] (6) Based on the kinetic calculation in step (5), the viscosity of the polyurethane model is calculated using formula 1 and formula 2. Formula 1:

[0012]

[0013] Among them, P xy (t) represents the stress tensor of the polyurethane model at time t, subscripts i and j represent the i-th and j-th particles, and x and y represent the three-dimensional coordinates;

[0014] Formula 2:

[0015]

[0016] Where η is the viscosity coefficient.

[0017] Furthermore, the compound containing a hydroxyl component in step (1) includes at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, n-butanol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,2-propylene glycol, 1,3-propylene glycol, polyether diol, polycaprolactone diol, polybutylene adipate diol and polycarbonate diol.

[0018] Furthermore, the compound containing an isocyanate component in step (1) includes at least one of isophorone diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,4-toluene diisocyanate, and 4,4′-dicyclohexylmethane diisocyanate.

[0019] Furthermore, the number of polyurethane molecular chains in step (3) is 5, the number of solvent molecules is 0-60, and the solvent molecules are one of acetone, butyl acetate, N,N-dimethylformamide, N-methylpyrrolidone, toluene and xylene.

[0020] Furthermore, the parameters of the Amorphous Cell module in step (3) include: density is set to 1.05, precision is selected as Ultra-fine, force field is selected as COMPASS, charge configuration is selected as Change using Gasteiger, optimize geometry is selected, structure optimization algorithm is selected as smart, energy convergence standard is selected as 0.00002, force field convergence standard is selected as 0.001, and optimization of unit cell is not selected.

[0021] Furthermore, the parameters for force field assignment in step (4) include: selecting Molecular as the force field type, selecting Gasteiger as the charge calculation method, setting the cutoff distance of van der Waals interaction to 8, clicking AutoAssign, and assigning the force field to the structure.

[0022] Furthermore, the parameters of the geometric optimization in step (4) include: selecting Conjugate gradient as the structural optimization algorithm, selecting 0.0001 as the energy convergence standard, selecting 0.000001 as the force field convergence standard, setting the maximum number of iterations for structural optimization to 1000, setting the maximum number of energy / force calculations to 10000, selecting optimized unit cell parameters, setting the maximum volume change allowed in a single iteration to 0.0005, and selecting Isostatic Pressure as the applied pressure.

[0023] Furthermore, the parameters of the molecular dynamics simulation calculation in step (5) include: NVT is selected as the dynamics simulation ensemble, the initial temperature and the final temperature are both selected as 298K, Nose-Hoover temperature control is selected as the temperature control method, the temperature control frequency is set to 100, the time step is 1fs, the total simulation time is 200000fs, the total number of simulation steps is 200000, and the calculation is repeated twice.

[0024] Furthermore, the parameters for viscosity calculation in step (6) include: time step of 1 fs, initial velocity set to Random, temperature of 298 K, sampling every 10 steps, correlation integration window size of 100, equilibrium time steps of 10,000, and result collection steps of 10,000.

[0025] The beneficial effects of the present invention are:

[0026] The present invention is based on a determined polyurethane resin. The polyurethane molecular chain is established using Materials Studio software by adjusting the molar ratio of the hydroxyl group to the isocyanate group in the hydroxyl compound and the isocyanate compound. The unit cell is then filled with the polyurethane molecular chain and solvent molecules to construct a polyurethane model. The polyurethane model is then subjected to force field distribution and geometric optimization using the LAMMPS module of the Matcloud+ material cloud computing platform to obtain an optimized polyurethane model. The optimized polyurethane model is then subjected to molecular dynamics simulation calculations. The viscosity coefficient η is then calculated based on the relationship between the stress tensor obtained from the molecular dynamics simulation and the viscosity coefficient η. The present invention uses molecular dynamics simulation to calculate the viscosity of the polyurethane resin. This method can rapidly establish a corresponding relationship between the polyurethane structure and the viscosity and simultaneously calculate the viscosities of multiple polyurethane resins, thereby rapidly screening polyurethane resins with suitable viscosities and reducing unnecessary physical experiments. The viscosity of the polyurethane resin obtained using this method is close to the actual viscosity, resulting in accurate results. This reduces the heavy workload of synthetic experiments and significantly reduces experimental costs. DETAILED DESCRIPTION

[0027] A high-throughput simulation calculation method for polyurethane resin viscosity of the present invention comprises the following steps:

[0028] (1) Select a hydroxyl compound and an isocyanate compound, and determine the molar ratio of the hydroxyl group to the isocyanate group in the hydroxyl compound and the isocyanate compound.

[0029] (2) Based on the molar ratio of hydroxyl group to isocyanate group in the hydroxyl compound and the isocyanate compound in step (1), a polyurethane molecular chain was established using the 3D Atomistic component of Materials Studio.

[0030] (3) The Amorphous Cell module in Materials Studio was used to fill the unit cell with the polyurethane molecular chains and 0-60 solvent molecules in the five steps (2) to construct a polyurethane model. The parameters of the Amorphous Cell module included: density was set to 1.05, precision was selected as Ultra-fine, force field was selected as COMPASS, charge configuration was selected as Change using Gasteiger, optimize geometry was selected, structure optimization algorithm was selected as smart, energy convergence criterion was selected as 0.00002, force field convergence criterion was selected as 0.001, and optimization of unit cell was not selected.

[0031] (4) The polyurethane model in step (3) was imported into the LAMMPS module of the Matcloud+ material cloud computing platform. The force field was first assigned to the polyurethane model. The parameters of the force field assignment included: Molecular was selected as the force field type, Gasteiger was selected as the charge calculation method, the cutoff distance of the van der Waals interaction was set to 8, and Auto Assign was clicked. Then, the polyurethane model with the force field assigned was geometrically optimized. The parameters of the geometric optimization included: Conjugate gradient was selected as the structure optimization algorithm, 0.0001 was selected as the energy convergence standard, 0.000001 was selected as the force field convergence standard, the maximum number of iterations for structure optimization was 1000, the maximum number of energy / force calculations was 10000, the optimized unit cell parameters were selected, the maximum volume change value allowed in a single iteration was set to 0.0005, and Isostatic Pressure was selected as the applied pressure to obtain the optimized polyurethane model.

[0032] (5) Molecular dynamics simulation calculations were performed on the polyurethane model optimized in step (4). The parameters of the molecular dynamics simulation calculations included: NVT was selected as the dynamics simulation ensemble, 298 K was selected for both the initial and final temperatures, Nose-Hoover temperature control was selected as the temperature control method, the temperature control frequency was set to 100, the time step was 1 fs, the total simulation time was 200,000 fs, the total number of simulation steps was 200,000, and the calculation was repeated twice.

[0033] (6) Based on the kinetic calculation in step (5), viscosity calculation is performed using the formula

[0034] Formula 1 and Formula 2 calculate the viscosity of the polyurethane model. Formula 1:

[0035]

[0036] Among them, P xy (t) represents the stress tensor of the polyurethane model at time t, subscripts i and j represent the i-th and j-th particles, and x and y represent the three-dimensional coordinates;

[0037] Formula 2:

[0038]

[0039] Where η is the viscosity coefficient.

[0040] The parameters for the viscosity calculation include: a time step of 1 fs, an initial velocity set to Random, a temperature of 298 K, sampling every 10 steps, a correlation integration window size of 100, an equilibrium time step of 10,000, and a result collection step of 10,000.

[0041] Among them, the compound containing a hydroxyl component includes at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, n-butanol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,2-propylene glycol, 1,3-propylene glycol, polyether diol, polycaprolactone diol, polybutylene adipate diol and polycarbonate diol; the compound containing an isocyanate component includes at least one of isophorone diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,4-toluene diisocyanate and 4,4′-dicyclohexylmethane diisocyanate; the solvent molecule includes one of acetone, butyl acetate, N,N-dimethylformamide, N-methylpyrrolidone, toluene and xylene. The high-throughput simulation calculation method for the viscosity of the polyurethane resin of the present invention can simulate and calculate the viscosity of multiple different polyurethane models at one time.

[0042] Example 1

[0043] The high-throughput simulation calculation method for polyurethane resin viscosity of this embodiment includes the following steps:

[0044] (1) Select polypropylene glycol and isophorone diisocyanate, and determine that the molar ratio of hydroxyl group to isocyanate group in polypropylene glycol and isophorone diisocyanate is 2:1.

[0045] (2) Based on the molar ratio of hydroxyl group to isocyanate group in the polypropylene glycol and isophorone diisocyanate of step (1) being 2:1, a polyurethane molecular chain was established using the 3D Atomistic component of Materials Studio.

[0046] (3) The Amorphous Cell module in Materials Studio was used to fill the unit cell with the polyurethane molecular chains and 38 N,N-dimethylformamide molecules in the five steps (2) to construct a polyurethane model. The parameters of the Amorphous Cell module included: density was set to 1.05, precision was selected as Ultra-fine, force field was selected as COMPASS, charge configuration was selected as Change using Gasteiger, optimize geometry was selected, structure optimization algorithm was selected as smart, energy convergence standard was selected as 0.00002, force field convergence standard was selected as 0.001, and optimization of unit cell was not selected.

[0047] (4) The polyurethane model in step (3) was imported into the LAMMPS module of the Matcloud+ material cloud computing platform. The force field was first assigned to the polyurethane model. The parameters of the force field assignment included: Molecular was selected as the force field type, Gasteiger was selected as the charge calculation method, the cutoff distance of the van der Waals interaction was set to 8, and Auto Assign was clicked. Then, the polyurethane model with the force field assigned was geometrically optimized. The parameters of the geometric optimization included: Conjugate gradient was selected as the structure optimization algorithm, 0.0001 was selected as the energy convergence standard, 0.000001 was selected as the force field convergence standard, the maximum number of iterations for structure optimization was 1000, the maximum number of energy / force calculations was 10000, the optimized unit cell parameters were selected, the maximum volume change value allowed in a single iteration was set to 0.0005, and Isostatic Pressure was selected as the applied pressure to obtain the optimized polyurethane model.

[0048] (5) Molecular dynamics simulation calculations were performed on the polyurethane model optimized in step (4). The parameters of the molecular dynamics simulation calculations included: NVT was selected as the dynamics simulation ensemble, 298 K was selected for both the initial and final temperatures, Nose-Hoover temperature control was selected as the temperature control method, the temperature control frequency was set to 100, the time step was 1 fs, the total simulation time was 200,000 fs, the total number of simulation steps was 200,000, and the calculation was repeated twice.

[0049] (6) Based on the dynamic calculation in step (5), viscosity calculation was performed. The parameters for viscosity calculation included: time step of 1 fs, initial velocity set to Random, temperature of 298 K, sampling every 10 steps, correlation integration window size of 100, equilibrium time steps of 10,000, and result collection steps of 10,000. Finally, the viscosity of the polyurethane model was calculated to be 230 mPa·s.

[0050] Example 2

[0051] The high-throughput simulation calculation method for the polyurethane resin viscosity of this embodiment is roughly the same as that of Example 1, except that in this embodiment, polypropylene glycol and 2,4-toluene diisocyanate are selected to establish the polyurethane molecular chain, wherein the molar ratio of polypropylene glycol to 2,4-toluene diisocyanate is 1:2. At the same time, in this embodiment, the solvent molecules are N-methylpyrrolidone, and the number is 30. The viscosity of the polyurethane model is calculated to be 780 mPa·s.

[0052] Example 3

[0053] The high-throughput simulation calculation method for the polyurethane resin viscosity of this embodiment is roughly the same as that of Example 1, except that in this embodiment, hydroxyethyl methacrylate and 4,4′-dicyclohexylmethane diisocyanate are selected to establish the polyurethane molecular chain, wherein the molar ratio of hydroxyethyl methacrylate to 4,4′-dicyclohexylmethane diisocyanate is 2:1. At the same time, in this embodiment, the solvent molecules are butyl acetate, and the number is 4. The viscosity of the polyurethane model is calculated to be 901 mPa·s.

[0054] Example 4

[0055] The high-throughput simulation calculation method for the polyurethane resin viscosity in this embodiment is substantially the same as that in Example 1, except that in this embodiment, n-butanol and 2,4-toluene diisocyanate are selected to establish the polyurethane molecular chain, wherein the molar ratio of n-butanol to 2,4-toluene diisocyanate is 2:1. Furthermore, in this embodiment, the solvent molecules are toluene, and the number is 4. The viscosity of the polyurethane model is calculated to be 400 mPa·s.

[0056] Example 5

[0057] The high-throughput simulation calculation method for the polyurethane resin viscosity in this embodiment is substantially the same as that in Example 1, except that in this embodiment, polycarbonate diol and isophorone diisocyanate are selected to establish the polyurethane molecular chain, wherein the molar ratio of polycarbonate diol to isophorone diisocyanate is 1:2. Furthermore, in this embodiment, acetone is used as the solvent molecule, and the number of the solvent molecules is 38. The viscosity of the polyurethane model is calculated to be 1780 mPa·s.

[0058] Comparative Example 1

[0059] The compound containing a hydroxyl component and the compound containing an isocyanate component used in this comparative example are the same as those in Example 1. The preparation method of the polyurethane resin of this comparative example includes the following steps:

[0060] (1) Weigh 2000 g of polypropylene glycol, 222 g of isophorone diisocyanate, 555.5 g of N,N-dimethylformamide, and 0.8 g of dibutyltin dilaurate.

[0061] (2) Polypropylene glycol, isophorone diisocyanate, N,N-dimethylformamide and dibutyltin dilaurate were mixed and added into a reactor, and reacted at a temperature of 80° C. for 3 h. The reaction was stopped to obtain the polyurethane resin of Control Example 1.

[0062] The viscosity of the polyurethane was measured at 298 K using a rotational viscometer according to GB / T 9751.1-2008. The viscosity of the polyurethane resin prepared in this comparative example was 211 mPa·s.

[0063] Comparative Example 2

[0064] The compound containing a hydroxyl component and the compound containing an isocyanate component used in this comparative example are the same as those in Example 2. The preparation method of the polyurethane resin of this comparative example includes the following steps:

[0065] (1) Weigh 1000 g of polypropylene glycol, 348 g of 2,4-toluene diisocyanate, 594 g of N-methylpyrrolidone, and 0.6 g of dibutyltin dilaurate.

[0066] (2) Polypropylene glycol, 2,4-toluene diisocyanate, N-methylpyrrolidone and dibutyltin dilaurate were mixed and added to a reactor. The mixture was reacted at 80° C. for 3 h. The reaction was stopped to obtain the polyurethane resin of Control Example 2.

[0067] The viscosity of the polyurethane was measured at 298 K using a rotational viscometer according to GB / T 9751.1-2008. The viscosity of the polyurethane resin prepared in this comparative example was 830 mPa·s.

[0068] Comparative Example 3

[0069] The compound containing a hydroxyl component and the compound containing an isocyanate component used in this comparative example are the same as those in Example 3. The preparation method of the polyurethane resin of this comparative example includes the following steps:

[0070] (1) Weigh 260 g of hydroxyethyl methacrylate, 262 g of 4,4′-dicyclohexylmethane diisocyanate, 92.8 g of butyl acetate, 0.16 g of dibutyltin dilaurate, and 1 g of 2,6-di-tert-butyl-p-cresol.

[0071] (2) Hydroxyethyl methacrylate, 4,4′-dicyclohexylmethane diisocyanate, butyl acetate, dibutyltin dilaurate and 2,6-di-tert-butyl-p-cresol were mixed and added to a reactor. The mixture was reacted at 80° C. for 3 h, and the reaction was stopped to obtain the polyurethane resin of Control Example 3.

[0072] The viscosity of the polyurethane was measured at 298 K using a rotational viscometer according to GB / T 9751.1-2008. The viscosity of the polyurethane resin prepared in this comparative example was 978 mPa·s.

[0073] Comparative Example 4

[0074] The compound containing a hydroxyl component and the compound containing an isocyanate component used in this comparative example are the same as those in Example 4. The preparation method of the polyurethane resin of this comparative example includes the following steps:

[0075] (1) Weigh 148 g of n-butanol, 174 g of 2,4-toluene diisocyanate, 73.6 g of toluene, and 0.16 g of dibutyltin dilaurate.

[0076] (2) n-Butanol, 2,4-toluene diisocyanate, toluene and dibutyltin dilaurate were mixed and added to a reactor, and reacted at a temperature of 80° C. for 2 h. The reaction was stopped to obtain the polyurethane resin of Control Example 4.

[0077] The viscosity of the polyurethane was measured at 298 K using a rotational viscometer according to GB / T 9751.1-2008. The viscosity of the polyurethane resin prepared in this comparative example was 360 mPa·s.

[0078] Comparative Example 5

[0079] The compound containing a hydroxyl component and the compound containing an isocyanate component used in this comparative example are the same as those in Example 5. The preparation method of the polyurethane resin of this comparative example includes the following steps:

[0080] (1) Weigh 1000 g of polycarbonate diol, 444 g of isophorone diisocyanate, 440.8 g of acetone, and 0.6 g of dibutyltin dilaurate.

[0081] (2) Polycarbonate diol, isophorone diisocyanate, acetone and dibutyltin dilaurate were mixed and added to a reactor. The mixture was reacted at 60° C. for 5 h. The reaction was stopped to obtain the polyurethane resin of Control Example 5.

[0082] The viscosity of the polyurethane was measured at 298 K using a rotational viscometer according to GB / T 9751.1-2008. The viscosity of the polyurethane resin prepared in this comparative example was 1662 mPa·s.

[0083] The viscosities of the polyurethane resins of Examples 1-5 and Comparative Examples 1-5 were compared, and the specific results are shown in Table 1:

[0084] Table 1 Viscosity measurement table

[0085]

[0086] A comparison of Examples 1-5 and Comparative Examples 1-5 in Table 1 demonstrates that the high-throughput simulation method for calculating polyurethane resin viscosity according to the present invention allows for rapid screening of polyurethane resins. By establishing corresponding polyurethane structural models on a computer, a relationship between polyurethane structure and viscosity is quickly established, thereby calculating the viscosity of the polyurethane resin. Furthermore, the present invention can simultaneously calculate the viscosity of multiple polyurethane structural models, reducing the laborious workload of synthetic experiments and significantly lowering experimental costs.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this field can make several improvements and supplements without departing from the method of the present invention. These improvements and supplements should also be considered within the scope of the present invention.

Claims

1. A high-throughput simulation calculation method for polyurethane resin viscosity, characterized in that: The following steps are involved: (1) Selecting a hydroxyl compound and an isocyanate compound, and determining the molar ratio of the hydroxyl group to the isocyanate group in the hydroxyl compound and the isocyanate compound; (2) Based on the molar ratio of hydroxyl group to isocyanate group in the hydroxyl compound and the isocyanate compound in step (1), a polyurethane molecular chain is established using the 3D Atomistic component of Materials Studio; (3) Using the AmorphousCell module in MaterialsStudio, the unit cell is filled with the polyurethane molecular chains and solvent molecules in step (2) to construct a polyurethane model; (4) The polyurethane model in step (3) is imported into the LAMMPS module of the Matcloud+ material cloud computing platform, and the force field is first assigned to the polyurethane model. Then, the geometry of the polyurethane model with the force field assigned is optimized to obtain the optimized polyurethane model. (5) Performing molecular dynamics simulation calculations on the polyurethane model optimized in step (4) to allow the system to reach equilibrium; (6) Based on the dynamic calculation in step (5), the following parameters for viscosity calculation are determined, including: time step of 1 fs, initial velocity set to Random, temperature of 298 K, sampling every 10 steps, correlation integration window size of 100, equilibrium time steps of 10,000, and result collection steps of 10,000. Finally, the viscosity of the polyurethane model is calculated.

2. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The compound containing a hydroxyl component in step (1) includes at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, n-butanol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,2-propylene glycol, 1,3-propylene glycol, polyether diol, polycaprolactone diol, polybutylene adipate diol and polycarbonate diol.

3. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The compound containing the isocyanate component in step (1) includes at least one of isophorone diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,4-toluene diisocyanate, and 4,4′-dicyclohexylmethane diisocyanate.

4. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The number of polyurethane molecular chains in step (3) is 5, the number of solvent molecules is 0-60, and the solvent molecules are one of acetone, butyl acetate, N,N-dimethylformamide, N-methylpyrrolidone, toluene and xylene.

5. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The parameters of the AmorphousCell module in step (3) include: density is set to 1.05, precision is selected as Ultra-fine, force field is selected as COMPASS, charge configuration is selected as Change using Gasteiger, optimize geometry is selected, structure optimization algorithm is selected as smart, energy convergence standard is selected as 0.00002, force field convergence standard is selected as 0.001, and optimization of unit cell is not selected.

6. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The parameters for force field assignment in step (4) include: selecting Molecular as the force field type, selecting Gasteiger as the charge calculation method, setting the cutoff distance for van der Waals interaction to 8, and clicking Auto Assign to assign the force field to the structure.

7. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The parameters of the geometric optimization in step (4) include: selecting Conjugate gradient as the structural optimization algorithm, selecting 0.0001 as the energy convergence standard, selecting 0.000001 as the force field convergence standard, setting the maximum number of iterations for structural optimization to 1000, setting the maximum number of energy / force calculations to 10000, selecting optimized unit cell parameters, setting the maximum volume change allowed in a single iteration to 0.0005, and selecting Isostatic Pressure as the applied pressure.

8. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The parameters of the molecular dynamics simulation calculation in step (5) include: NVT is selected as the dynamics simulation ensemble, the initial temperature and the final temperature are both selected as 298K, Nose-Hoover temperature control is selected as the temperature control method, the temperature control frequency is set to 100, the time step is 1fs, the total simulation time is 200000fs, the total number of simulation steps is 200000, and the calculation is repeated twice.

9. The high-throughput simulation calculation method for polyurethane resin viscosity according to claim 1, characterized in that: The parameters for viscosity calculation in step (6) include: time step of 1 fs, initial velocity set to Random, temperature of 298 K, sampling every 10 steps, correlation integration window size of 100, equilibrium time steps of 10,000, and result collection steps of 10,000.

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