Effect of Molecular Chain Length on the Mechanical and Thermal Properties of Amine-Functionalized Graphene Oxide/Polyimide Composite Films Prepared by In Situ Polymerization

Thermostable well-functionalized graphene oxide/polyimide composites with high dielectric constant and low dielectric loss were obtained at a low percolation threshold.

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Effect of Amine Molecular Chain Length on the Mechanical and Thermal Properties of Functionalized Graphene Oxide/Polyurea Nanocomposites

Science of Advanced Materials ◽

10.1166/sam.2021.3897 ◽

2021 ◽

Vol 13 (2) ◽

pp. 199-208

Author(s):

Qiang Zhao ◽

Si Ouyang ◽

Gang Chen ◽

Yiqing Deng ◽

Mengxiao Chen ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Chemical Conversion ◽

Mechanical And Thermal Properties ◽

Functionalized Graphene ◽

Scanning Calorimetry ◽

Functionalized Graphene Oxide ◽

New Approach ◽

Chain Lengths

To improve the overall performance of polyurea, linear diamines with three different chain lengths (1,2-ethylenediamine (EDA) and amino-terminated polyoxypropylenes D230 and D2000) were reacted with graphene oxide (GO) by reaction of amines with carboxyl groups, and three different amino-functionalized graphene oxide (AGO) nanosheets (EDA-GO, D230-GO and D2000-GO) were prepared. Subsequently, an AGO flake was bonded to a polyurea (PUA) substrate by an in situ chemical process. Analytical tests, including X-ray photoelectron spectroscopy (XPS), showed that diamines were attached to the GO flake. The reinforcement properties of the nanocomposites were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile testing. AGO nanosheets, especially EDA-GO, result in a certain degree of enhancement in the thermal and mechanical properties of nanocomposites formed with polyurea. The TGA and DSC results indicated that the T5% and Tg of the nanocomposites at low AGO loading were increased compared with those of pure polyurea. Meanwhile, the elongation at break of the nanocomposite film with 0.1 wt% EDA-GO loading was 240% higher than that of pure polyurea, and tensile strength was increased by 80% over that of pure polyurea. We provide a new approach to the chemical conversion of GO/PUA nanocomposites by preparing AGO and complexing it with polyurea.

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Dielectric, mechanical and thermal properties of all-organic PI/PSF composite films by in situ polymerization

e-Polymers ◽

10.1515/epoly-2020-0020 ◽

2020 ◽

Vol 20 (1) ◽

pp. 226-232 ◽

Cited By ~ 4

Author(s):

Peng Li ◽

Jiajun Yu ◽

Shaohua Jiang ◽

Hong Fang ◽

Kunming Liu ◽

...

Keyword(s):

Thermal Properties ◽

In Situ Polymerization ◽

Composite Films ◽

Dielectric Materials ◽

Mechanical Analysis ◽

Dielectric Measurement ◽

Mechanical And Thermal Properties ◽

High Dielectric Materials ◽

High Dielectric

AbstractAll-organic high dielectric materials are highly required in the field of modern electronic industry and energy storage. In this work, all-organic polyimide/polysulfone composite films with different amounts of PSF (PI/PSF-X) were prepared by in situ polymerization followed by film casting and thermal treatment. The dielectric, mechanical and thermal properties of these PI/PSF-X composite films are characterized by dielectric measurement, tensile test, thermogravimetric analysis and dynamic mechanical analysis. The results suggest that the PI/PSF-X composite films have good dielectric properties, good mechanical properties and excellent thermal properties, which are suitable for applications in electronic devices in harsh environments, especially in high-temperature environments.

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