Thermal Degradation Kinetics and Modeling Study of Ultra High Molecular Weight Polyethylene (UHMWP)/Graphene Nanocomposite
Iman Jafari,
Mohamadreza Shakiba,
Fatemeh Khosravi,
Seeram Ramakrishna,
Ehsan Abasi,
Ying Shen Teo,
Mohammadreza Kalaee,
Majid Abdouss,
Ahmad Ramazani S. A,
Omid Moradi,
Erfan Rezvani Ghomi
Affiliations
Iman Jafari
Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Singapore 117576, Singapore
Mohamadreza Shakiba
Department of Chemistry, Amirkabir University of Technology, Tehran 15875-4413, Iran
Fatemeh Khosravi
Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, Faculty of Engineering, National University of Singapore, Singapore 117581, Singapore
Seeram Ramakrishna
Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, Faculty of Engineering, National University of Singapore, Singapore 117581, Singapore
Ehsan Abasi
Department of Polymer and Chemical Engineering, South Tehran Branch, Islamic Azad University, Tehran 17776-13651, Iran
Ying Shen Teo
Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Singapore 117576, Singapore
Mohammadreza Kalaee
Department of Polymer and Chemical Engineering, South Tehran Branch, Islamic Azad University, Tehran 17776-13651, Iran
Majid Abdouss
Department of Chemistry, Amirkabir University of Technology, Tehran 15875-4413, Iran
Ahmad Ramazani S. A
Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran 11365-9465, Iran
Omid Moradi
Department of Chemistry, Shahre-Qods Branch, Islamic Azad University, Shahre-Qods 37515-374, Iran
Erfan Rezvani Ghomi
Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, Faculty of Engineering, National University of Singapore, Singapore 117581, Singapore
The incorporation of nanofillers such as graphene into polymers has shown significant improvements in mechanical characteristics, thermal stability, and conductivity of resulting polymeric nanocomposites. To this aim, the influence of incorporation of graphene nanosheets into ultra-high molecular weight polyethylene (UHMWPE) on the thermal behavior and degradation kinetics of UHMWPE/graphene nanocomposites was investigated. Scanning electron microscopy (SEM) analysis revealed that graphene nanosheets were uniformly spread throughout the UHMWPE’s molecular chains. X-Ray Diffraction (XRD) data posited that the morphology of dispersed graphene sheets in UHMWPE was exfoliated. Non-isothermal differential scanning calorimetry (DSC) studies identified a more pronounced increase in melting temperatures and latent heat of fusions in nanocomposites compared to UHMWPE at lower concentrations of graphene. Thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) revealed that UHMWPE’s thermal stability has been improved via incorporating graphene nanosheets. Further, degradation kinetics of neat polymer and nanocomposites have been modeled using equations such as Friedman, Ozawa–Flynn–Wall (OFW), Kissinger, and Augis and Bennett’s. The "Model-Fitting Method” showed that the auto-catalytic nth-order mechanism provided a highly consistent and appropriate fit to describe the degradation mechanism of UHMWPE and its graphene nanocomposites. In addition, the calculated activation energy (Ea) of thermal degradation was enhanced by an increase in graphene concentration up to 2.1 wt.%, followed by a decrease in higher graphene content.
