A joint density functional and classical molecular dynamics study on interface characteristics of graphene and polyetheretherketone


Thesis Type: Postgraduate

Institution Of The Thesis: Middle East Technical University, Turkey

Approval Date: 2020

Student: Elif Sert

Supervisor: HANDE TOFFOLİ

Abstract:

Graphene is a single layer allotrope of carbon with a honeycomb arrangement of atoms, characterized by excellent mechanical properties such as high tensile strength, high Young’s modulus as well as desirable electrical properties such as high electron mobility. Due to these superior properties, it is considered an important material in numerous technological applications. Among these, graphene-polymer composites have attracted significant interest in the materials research community in recent years. The use of these composites are particularly important in such fields as aeronautics where strength and low mass are simultaneously desirable. The testing, processing and construction of applicable mixtures of graphene and polymers pose challenges experimentally. Therefore, numerical modeling of graphene and graphene reinforced polymer composites is essential. The main purpose of this thesis is to study the properties of the interface between graphene and the Poly Ether Ether Ketone (PEEK) polymer within the Density Functional Theory (DFT) and Molecular Dynamics (MD) frameworks. PEEK is a high performing thermoplastic polymer with remarkable mechanical characteristics, chemv ical resistance, and relative high melting temperatures. We study the interaction from the smallest building units of a single monomer and build it up to 3-, 6- and 9-monomer chains, revealing all of its facets. In addition, we adhesion characteristics between graphene and PEEK oligomers as they slide past one another as a function of such important parameters as velocity, temperature and chain length.