Method for simulating deformation of rubber compound

摘要

A method for simulating deformation of rubber compound including silica particles and an interfacial coupling agent therefor is disclosed. Using a scanning transmission electron microscope (STEM), data of STEM images of the rubber compound are acquired. Based on the STEM image data, a dataset of a 3D structure of the rubber compound is reconstructed. Based on the dataset, a model of the rubber compound is generated. Using the model on which conditions are defined, a deformation calculation is made and a physical quantity is acquired. The rubber compound model comprises a rubber component model, silica particle models and interface models surrounding the silica particle models and defined as being harder than the rubber component model.

主权项

1. A method for simulating deformation of rubber compound including a rubber component, silica particles and an interfacial coupling agent for coupling the silica particles with the rubber component, comprising:
a STEM image acquiring step of acquiring, by the use of a scanning transmission electron microscope (STEM), data of STEM images of the rubber compound; a three-dimensional structure reconstruction step of reconstructing, based on the data of the STEM images, a dataset of a three-dimensional structure of the rubber compound; a finite element model generating step of generating, based on the dataset of the three-dimensional structure of the rubber compound, a finite element model of the rubber compound; a deformation calculation step of making a deformation calculation by the use of the finite element model of the rubber compound on which conditions are defined; and a step of acquiring a physical quantity through the deformation calculation, wherein the finite element model generating step comprises the steps of:
reconstructing data of a slice image of the rubber compound from the dataset of the three-dimensional structure;identifying a domain of the rubber component and domains of the silica particles in the slice image through an image processing of the slice image; andgenerating the finite element model of the rubber compound, wherein the step of generating of the finite element model further comprises the steps of:
creating silica particle models by subdividing the domains of the silica particles into finite elements;creating an interface model made up of finite elements surrounding each of the silica particle models;creating a rubber component model by subdividing the domain of the rubber component into finite elements; anddefining a physical property on the finite elements of the interface models as being harder than the rubber component, wherein the physical property of the interface model is determined by the steps of: preparing a first unvulcanized rubber compound having the same composition as that of said rubber compound as an analysis object and a second unvulcanized rubber compound having a composition same as the first unvulcanized rubber compound except that the interfacial coupling agent is eliminated; immersing each of the first and second unvulcanized rubber compounds in solvent to remove the rubber component and thereby to obtain residue; determining the difference between a peak temperature T1 of a loss tangent of the residue of the first unvulcanized rubber compound and a peak temperature T2 of the loss tangent of the residue of the second unvulcanized rubber compound; preparing a basic vulcanized rubber compound having a composition same as the first unvulcanized rubber compound except that the silica particles are eliminated, and plural kinds of vulcanized rubber compounds which are the same as the basic vulcanized rubber compound but different in a crosslink density from each other and from the basic vulcanized rubber compound; measuring a peak temperature of the loss tangent of each of the vulcanized rubber compounds, which are the basic vulcanized rubber compound and said plural kinds of vulcanized rubber compounds; obtaining, from the measured peak temperature and the crosslink density of each of the vulcanized rubber compounds which are said basic vulcanized rubber compound and said plural kinds of vulcanized rubber compounds, a relationship between the peak temperature of the loss tangent and the crosslink density; finding, from the obtained relationship, the crosslink density when the peak temperature of the loss tangent is equal to the sum of the difference |T2−T1| and the peak temperature T3 of the loss tangent of the basic vulcanized rubber compound; and measuring the physical property of a vulcanized rubber compound having the found crosslink density and defining the physical property for the interface model.