Method and system for evaluating the flowability of polymer materials by molecular simulation

Abstract

The invention discloses a method for evaluating the flowability of a polymer material by adopting a molecular simulation method. The method comprises the following steps: constructing a single chain structure of the polymer to be tested according to a repeating unit of the polymer to be tested; establishing a bulk structure model of the polymer according to the structure parameters and ingredientsof the polymer; carrying out the first relaxation of the bulk structure model, the first selection of the global optimum configuration of the NVT ensemble, the second relaxation of the configuration,the second selection of the global optimum configuration of the NPT ensemble, and the cooling annealing simulation of the NVT and NPT ensembles in order to make the configuration and density of the model fully balanced, and obtaining the second structure data; carrying out sufficient dynamic equilibrium on the second structural data to obtain the dynamic trajectory data; testing the validity of the viscosity data was tested by the stress autocorrelation function analysis of the kinetic trajectory data, and obtaining the reliable shear viscosity data of the polymer . The method of the invention can quickly, efficiently and accurately calculate the shear viscosity data of the polymer material.

Description

technical field [0001] The invention relates to the technical field of polymer simulation, in particular to a method and a system for evaluating the flow performance of polymer materials by using a molecular simulation method. Background technique [0002] Polymers can be divided into oligomers and high polymers (high molecular compounds). Natural polymer compounds and synthetic materials based on polymers, such as plastics, synthetic rubber, synthetic fibers, coatings and adhesives, have very important application values ​​in the national economy. [0003] The process of processing polymers into various products is closely related to the fluidity of polymers. Studying the flow properties of materials is of great significance to the synthesis, processing and design of polymers, as well as further improving the processing performance of polymers, correctly selecting processing conditions, and guiding formula design. The flow performance of materials is an important processi...

AI Technical Summary

Problems solved by technology

However, this method is limited by the experience and level of software users, difficult to operate, low in efficiency, and unable to be popularized and calculated on a large scale.

Moreover, the accuracy of the research results is poor, the data discrepancies are large, and the guidance and reference for the development and design of new materials are insufficient.

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