CN-115561281-B - Polymer in-situ characterization method based on conductive two-dimensional material

CN115561281BCN 115561281 BCN115561281 BCN 115561281BCN-115561281-B

Abstract

The invention discloses a polymer in-situ characterization method based on a conductive two-dimensional material, which comprises the steps of firstly preparing a conductive two-dimensional material film and a polymer film, constructing a composite material based on the conductive two-dimensional material film and the polymer film, enabling the conductive two-dimensional material film to be an electrical probe and uniformly and orderly dispersed in different polymer matrixes, forming a continuous conductive path in the composite material, taking the composite material as a platformization test primitive, measuring the resistance of the composite material to obtain a resistance change curve, analyzing and processing the resistance change curve of the composite material to obtain the structural change of the polymer matrix in the thermal conversion and degradation processes, and calculating the glass transition temperature and the melting point of the polymer matrix. The method can be applied to important fields such as characterization of polymer thermal performance, research of polymer degradation process, evaluation of polymer degradability and the like.

Inventors

LIU PINGWEI
DU JIGANG
WANG WENJUN

Assignees

浙江大学

Dates

Publication Date: 20260505
Application Date: 20221025

Claims (8)

1. A method for in-situ characterization of a polymer based on a conductive two-dimensional material, characterized in that it comprises in particular the following steps: (1) Preparing a conductive two-dimensional material film and a polymer film, and constructing a composite material based on the conductive two-dimensional material film and the polymer film, so that the conductive two-dimensional material film is an electrical probe and is uniformly and orderly dispersed in different polymer matrixes, and a continuous conductive path is formed in the composite material; (2) Taking the composite material constructed in the step (1) as a platform test primitive, measuring the resistance of the composite material to obtain a resistance change curve, analyzing and processing the resistance change curve of the composite material to obtain the structural change of the polymer matrix in the thermal conversion and degradation processes, and calculating the glass transition temperature and melting point of the polymer matrix; Transferring a continuous two-dimensional conductive material film to the surface of a polymer film to construct a composite film, and further processing the composite film into vortex fiber by a transverse shearing rolling method to obtain the composite material; The process of measuring the resistance of the composite material comprises the steps of partially etching polymer layers at two ends of the vortex fiber by using a solvent compatible with a polymer matrix, and coating a conductive adhesive coating at the etched part to realize the conduction between the internal conductive two-dimensional material and an external circuit.
2. The method of claim 1, wherein the conductive two-dimensional material film comprises graphene, a two-dimensional metal material, a two-dimensional covalent organic framework material, a two-dimensional metal organic framework material, a two-dimensional conductive polymer.
3. The method for in-situ characterization of a polymer based on a conductive two-dimensional material according to claim 2, wherein the processing method of the conductive two-dimensional material film comprises chemical vapor deposition, epitaxial growth, ink-jet printing, suction filtration, solvent evaporation, interfacial growth, hydrothermal synthesis or electrochemical synthesis, and the thickness of the conductive two-dimensional material film is less than 100 nm.
4. The method of claim 1, wherein the polymer matrix is a polymer material having a glass transition, a thermal transition behavior including melting, or a polymer material that is degradable by environmental factors.
5. The method of in situ characterization of a conductive two-dimensional material based polymer of claim 4, wherein the polymer matrix comprises a thermoplastic, a polyolefin material or a polyester material, wherein the thermoplastic comprises a polycarbonate, a polystyrene or a polymethyl methacrylate, wherein the polyolefin material comprises a polyethylene, a polypropylene or a polyolefin thermoplastic elastomer, and wherein the polyester material comprises polyethylene terephthalate, polybutylene adipate terephthalate, polycaprolactone, and polyamides, polyimides.
6. The method for in-situ characterization of a polymer based on a conductive two-dimensional material according to claim 1 or 5, wherein the process for preparing the polymer film comprises hot pressing, spin coating, knife coating or solvent evaporation, and the thickness of the polymer film is 0.5-30 μm.
7. The method for in-situ characterization of a polymer based on a conductive two-dimensional material according to claim 1, wherein the structural change of the polymer during thermal transformation includes glass transition, chain movement during melting, chain breakage, and the glass transition temperature and melting point of the polymer matrix are quantitatively calculated by analyzing the resistance change curve, the structural change of the polymer during degradation includes photodegradation, thermal degradation, and microbial degradation, and the formation of free radicals, and the degradation rate of the polymer can be evaluated by analyzing the degradation of the polymer during the resistance change curve.
8. The method for characterizing a polymer in situ based on a conductive two-dimensional material according to claim 1 or 7, wherein the process of quantitatively calculating the glass transition temperature and the melting point of the polymer matrix by analyzing the resistance change curve includes differentiating the resistance change curve for the glass transition, finding the temperature corresponding to the maximum value of the differentiation, namely, the glass transition temperature corresponding to the polymer matrix, fitting straight lines to the resistance change curve in the initial stage and the end stage of melting phase transformation, and the intersection points of the straight lines corresponding to the initial stage and the end stage respectively are the melting point of the polymer matrix.

Description

Polymer in-situ characterization method based on conductive two-dimensional material Technical Field The invention relates to the field of polymer material characterization, in particular to a polymer in-situ characterization method based on a two-dimensional material. Background The characterization of the polymer is an important means for knowing the chemical composition, molecular weight distribution and other physical properties of the polymer, and has important guiding significance for the processing and application of the polymer. Although various reliable techniques have been established to characterize various properties of polymers, there is a problem in that, first, the study of different properties of polymers requires different sample states and the introduction of various complex devices due to the lack of a common characterization platform, which makes this process time-consuming, labor-consuming and costly. Furthermore, it is difficult to achieve rapid in situ characterization of the macroscopic polymeric material after processing, such as thermal transformation and degradation processes of the polymeric material. These problems greatly limit the development and application of multifunctional polymer materials, and the deep understanding and regulation of the polymer degradation process, are important challenges for the development of polymer science at present. Therefore, developing a low-cost, platform-based polymer in-situ characterization technique is a technical problem that needs to be solved currently. Disclosure of Invention The invention aims at providing a polymer in-situ characterization test technical means aiming at the defects of the existing polymer characterization technology. The invention aims at realizing the technical scheme that the polymer in-situ characterization method based on the conductive two-dimensional material comprises the following steps of: (1) Preparing a conductive two-dimensional material film and a polymer film, and constructing a composite material based on the conductive two-dimensional material film and the polymer film, so that the conductive two-dimensional material film is an electrical probe and is uniformly and orderly dispersed in different polymer matrixes, and a continuous conductive path is formed in the composite material; (2) Taking the composite material constructed in the step (1) as a platform test element, measuring the resistance of the composite material to obtain a resistance change curve, analyzing and processing the resistance change curve of the composite material to obtain the structural change of the polymer matrix in the thermal conversion and degradation processes, and calculating the glass transition temperature and the melting point of the polymer matrix. Further, the conductive two-dimensional material film comprises graphene, a two-dimensional metal material, a two-dimensional covalent organic framework material, a two-dimensional metal organic framework material and a two-dimensional conductive polymer Further, the processing method of the conductive two-dimensional material film comprises chemical vapor deposition, epitaxial growth, ink-jet printing, suction filtration, solvent volatilization, interface growth, hydrothermal synthesis or electrochemical synthesis, wherein the thickness of the conductive two-dimensional material film is smaller than 100nm. Further, the polymer matrix is a polymer material having a glass transition, a thermal transition behavior including melting, or a polymer material that can be degraded by environmental factors. Further, the polymer matrix comprises thermoplastic plastics, polyolefin materials or polyester materials, wherein the thermoplastic plastics comprise polycarbonate, polystyrene or polymethyl methacrylate, the polyolefin materials comprise polyethylene, polypropylene or polyolefin thermoplastic elastomers, and the polyester materials comprise polyethylene terephthalate, polybutylene adipate terephthalate, polycaprolactone, polyamide and polyimide. Further, the process for preparing the polymer film comprises a hot-pressing, spin-coating, knife-coating or solvent-volatilizing method for preparing the polymer film, wherein the thickness of the polymer film is 0.5-30 mu m. The process of constructing the composite material based on the conductive two-dimensional material film and the polymer film comprises the steps of transferring the continuous two-dimensional conductive material film to the surface of the polymer film to construct the composite film, and further processing the composite film into vortex fiber by a transverse shearing rolling method to obtain the composite material. Further, the process of measuring the resistance of the composite material comprises the steps of partially etching the polymer layers at the two ends of the vortex fiber by using a solvent compatible with the polymer matrix, and coating a conductive adhesive coating at the etched part to realize the co