Achieving high-performance epoxy nanocomposites with trifunctional poly(oxypropylene)amines functionalized graphene oxide

Abstract

In this article, two types of functional graphene oxide (GO) with amine-rich surface were synthesized through chemically grafting two different molecular chain length trifunctional poly(oxypropylene)amines T5000 and T403, which were named as T5000-GO and T403-GO, respectively. The functionalized GO was then added to epoxy (EP) resin. Fourier transform infrared spectra analysis confirmed successful chemical functionalization on GO. Both T403-GO and T5000-GO were tightly embedded in the EP, because the amine-rich surface of functionalized-GO could form covalent bonds with the EP matrix, thereby contributing to the enhancement of mechanical properties. Particularly, T5000-GO, which has longer grafting molecule chains, achieved better compatibility and dispersibility in the EP matrix, resulting in a better reinforcing efficiency in mechanical properties. For example, the T5000-GO/EP composites showed an incremental enhancement in tensile strength with increasing filler concentrations, whereas their T403-GO/EP counterparts failed to follow the same trend. Meanwhile, the T5000-GO/EP composites with only 0.1-wt% T5000-GO achieved a prominent increase in flexural strength (approximately 50%) and flexural modulus (approximately 26.8%), which were higher than those of T403-GO-filled counterparts. This work indicated that the compatibility and interphase between GO and EP could be designed by manipulating the length of grafting molecule chains, thereby providing a better understanding of the relationship between the structure and mechanical properties of the graphene/EP nanocomposites.

Polyoxazoline‐modified graphene oxides with improved water and epoxy resin dispersibility and stability towards composite applications

“…In addition, all modified GOs have better thermal stability than the neat GO as the peak representing the maximum weight loss shifts from 220 to 350°C due to the polymer incorporation as for the neat polymers, 100% weight loss is observed between 350 and 400°C. The decomposition of grafted polymers starts earlier than neat polymers, demonstrating that the presence of GO affect the decomposition behavior of the attached polymers 60 …”

Graphene Oxide/Polymer-Based Multi-scale Reinforcement Structures for Enhanced Interfacial Properties of Carbon Fiber Composites

“…The hardener 4,4-diaminodiphenylmethane was supplied by Wengjiang Co., Ltd. (Guangdong, China). GO was synthesized in our lab . Potassium hydroxide (KOH), sulfuric acid (H 2 SO 4 ), p -aminobenzoic acid, and itaconic acid were supplied by Shanghai Aladdin Reagent Co., Ltd.…”

A Review on the Contemporary Development of Composite Materials Comprising Graphene/Graphene Derivatives

“…Simultaneously, surface functional modification using non-covalent bonds can be used to improve the dispersibility of Gr, but the resulting graphene composite is unstable and its intermolecular forces are weak. Comparatively, covalent bond functional modification is achieved by introducing a functional group capable of forming a covalent bond with reactive double bonds or another oxygen-containing group on the Gr or GO surface [29,30]. Compared with non-covalent bond functionalization, covalent bond functionalization is more stable but affects performance because it destroys the structure of Gr.…”