Amine-graphene oxide/waterborne polyurethane nanocomposites: effects of different amine modifiers on physical properties

Abstract

To study the dispersity of different amine-graphene oxide (amine-GO) in polymer matrix and the interfacial interactions between functionalized graphene oxide and matrix, two kinds of modifiers-organoamine-and aminosilane-coupling agents-were used to functionalize graphene nanosheets to obtain functionalized graphene oxide/waterborne polyurethane nanocomposites by in situ polymerization. The chemical structure, morphology, and interlayer space of amine-GO nanoplatelets were confirmed by FT-IR, Raman, TGA, XPS, TEM, AFM, and XRD. The dispersity behaviors between different amineGOs and polymers were evaluated by FESEM. The thermal, mechanical, and hydrophobic properties of the nanocomposites were investigated by TGA, tensile testing machine, and water contact angle test, respectively. It was found that the tensile strength of nanocomposites was increased from 10.13 to 27.79 and 28.96 Mpa after the addition of amine-GO functionalized by APTMS and APTES, respectively. The better thermal stability and hydrophobicity of nanocomposites were also achieved by the addition of amine-GO, especially those modified by aminosilane-coupling agents. This study paves a new route for designing and developing chemically converted graphene oxide nanosheets/polymer nanocomposite materials by altering suitable amine-modifier to functionalize graphene oxide nanosheets and then optimizing the interphases between graphene oxide nanosheets and polymer matrices.

A review on the role of interface in mechanical, thermal, and electrical properties of polymer composites

“…For different polymer nanocomposites, T g was shown to be increased [206,207], decreased [180,208], or even unaffected [182,209] by the introduction of fillers into the system. More studies are summarized in Table 2.…”

“…The presence of reinforcing agents in the matrix can increase the thermal stability in different ways. First, they can act as a barrier, which makes them useful for flame retardation applications [209,227,228]. Second, they can create a network which can protect the polymer from degradation [229][230][231][232].…”

WPU/CB/GO nanocomposites: in situ polymerization preparation, thermal, and anticorrosion performance evaluation

“…An enhancement of T d could be observed in Table obtained from Figures and . The authors believe that five main factors could account for this enhancement: a , directional distribution of GO layers in polymer substrate as the result of strong hydrogen‐bonding existing between GO and WPU as well as the fundamental factor‐uniformly dispersed composite fillers in the matrix; b , strong interaction between composite fillers and matrix; c , the restricted polymer chain movement because of the enhancement of crosslinking density of WPU substrate after adding CB and GO; d , the added composite fillers also serve as barrier layers to prevent heat and mass transfer between the external environment and the polymer; and e , the synergetic effect of fillers …”

Mechanical Properties, Thermal Stability, and Glass Transition Behaviors of a Waterborne Polyurethane/Graphene Oxide Nanocomposite

“…The decrease of the mechanical properties above a certain GO content was observed in many studies 26,27) . In many studies 13,18,19,28,29) , the incorporation of GO or functionalized graphene results in the decreased EB. Thus, it is meaningful that both stiffness and toughness increase with the incorporation of GO nanosheets in this study.…”

“…They observed increased stiffness and thermal stability but decreased elongation-at-break with the incorporation of GO in WPU. Hu et al prepared four different amine functionalized GO and synthesized WPU/ amine-GO nanocomposites by in situ polymerization 19) . The stiffness, thermal stability, and hydrophobicity of the composites were increased by the addition of amine-GO but the elongation-at-break was slightly decreased.…”