Determination method of topological network structure transition temperature of glass-like polymer materials

Abstract

The invention discloses a method for measuring the topological network structure transition temperature of a glass-like polymer material. The method comprises the steps of: providing a glass-like polymer material and aggregation-induced luminescence molecules, wherein the glass-like polymer material has a cross-linked network; the cross-linked network comprises a dynamic covalent bond responding to thermal stimulus; and the aggregation-induced luminescence molecules are doped in the cross-linked network; measuring multiple fluorescence intensities of the aggregation-induced luminescence molecules corresponding to multiple temperature points in a predetermined temperature range in a temperature increasing or decreasing process; drawing a curve that the fluorescence intensities are changed along with the temperature by utilizing the multiple temperature points and the multiple fluorescence intensities, wherein the curve comprises multiple slope-constant straight sections and multiple slope-changed arc sections; and, according to the known glass transition temperature of the glass-like polymer material, determining the temperature interval corresponding to the first arc section, whichdoes not include the glass transition temperature, as the first temperature interval, where the topological network structure transition temperature is.

Description

technical field [0001] The invention relates to the field of polymer materials, in particular to a method for measuring the transition temperature of a topological network structure of a glass-like polymer material. Background technique [0002] Polymer materials can be simply divided into two types: thermosetting polymers and thermoplastic polymers. Thermoplastic polymers can be repeatedly processed and shaped, but their thermodynamic properties are poor. Thermosetting polymers are just the opposite. They have higher mechanical strength and better pressure and heat resistance. However, because thermosetting materials are three-dimensional cross-linked networks, they are insoluble and insoluble. Once processed and shaped, they cannot be processed and reshaped. . Therefore, when the thermosetting material is aged and damaged, it becomes waste, which not only causes waste of resources, but also causes environmental pollution and other problems in waste disposal. If thermose...

AI Technical Summary

Problems solved by technology

Existing methods can accurately measure T v There are few methods, the traditional measurement of phase transition temperature (such as glass transition temperature T g , melting point T m ) Differential Scanning Calorimetry (DSC) cannot be used to measure T v At present, only dilatometry test, stress relaxation method and rheometer are used to measure T v

Although the dynamically reorganizing network has a higher expansion coefficient than the static network, the expansion curve of the glassy polymer is at T v At , the expansion change is not obvious, so it is difficult to accurately determine T v temperature

This makes the determination of T of glass-like polymers in different literatures v The results obtained vary widely and are controversial

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