E-Thesis 167 views
Enhancing the Barrier Properties of Recycled Polymers by Incorporating Nano-Particles / DALAL ALSHAMMARI
Swansea University Author: DALAL ALSHAMMARI
DOI (Published version): 10.23889/SUthesis.67438
Abstract
The emergence of recyclable polymers holds the remarkable potential to preserve the natural ecosystem and resolve the end-of-life issue associated with plastic waste. Every year, tons of plastic arebeing generated by the industrial sector and a large proportion of it stems from packaging and protect...
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Swansea, Wales, UK
2022
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| Institution: | Swansea University |
| Degree level: | Doctoral |
| Degree name: | Ph.D |
| Supervisor: | Korkees, Feras |
| URI: | https://cronfa.swan.ac.uk/Record/cronfa67438 |
| Abstract: |
The emergence of recyclable polymers holds the remarkable potential to preserve the natural ecosystem and resolve the end-of-life issue associated with plastic waste. Every year, tons of plastic arebeing generated by the industrial sector and a large proportion of it stems from packaging and protective industries which ultimately requires enhanced barrier properties. It is therefore highly desired to use recycled polymers and improve the barrier properties of recycled polymers. The addition of nano-fillers in the recycled polymers to produce polymer nanocomposites (PNCs) works as reinforcing agents to restore the properties of the polymers that emerged from the degradation of thermoplastic polymer chains, particularly after the recycling of polymers. In this context, reducing the permeability of water vapours in recycled polymers is of paramount importance in the packaging and protective industries. Diffusing species can be successfully prevented by increasing the tortuosity of the pathways for the permeants, which can be successfully achieved by the inclusion of impermeable nanofillers. Herein, the current study focuses on the inclusion of graphene nanofillers functionalized with Amine (NH2) and oxygen (O2) in recycled polymer matrices including Nylon 6 or polyamide (PA6), (PA66) and Polyethylene terephthalate (PET) to improve their water barrier properties. Functionalized graphene nanofillers have been chosen owing to their excellent dispersion, ability to increase bonding between the fillers and the matrix as well as increase the tortuosity of the diffusing species and ultimately enhance the barrier properties of the resultant PNCs. The PNCs were prepared using the twin-screw extrusion method and different concentrations of (NH2) and oxygen (O2) functionalized graphene have been added to prepare these composites. The PNCs were tested for their barrier and absorption properties. It is revealed that PET demonstrated to be an excellent composite which showed remarkable barrier properties as compared to PA6 and PA66 based composites. A typical Fickian absorption behaviour has been exhibited by these polymers while the absorption was observed to be directly correlated with the temperature, that is, absorption was significantly increased at elevated temperatures. Scanning electron microscopy (SEM) and Fourier transformed infrared (FTIR) spectroscopy also confirmed the efficacy of PET over PA6 and PA66. Two sample thicknesses were tested for the permeability tests and the results revealed that saturation time for absorption is largely thickness dependent. While thicker samples take almost double the time asthe thinner sample to saturate. However, the difference becomes almost insignificant at higher temperatures and the saturation phenomenon becomes more the temperature is driven. The findings of the current study will definitely provide the base to further explore the potential of graphene-based nanofillers in different polymeric matrices. |
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| Item Description: |
ORCiD identifier: https://orcid.org/0009-0000-3204-8541 |
| Keywords: |
nanocomposite; graphene; recycled polymers; barrier properties; absorption behavior |
| College: |
Faculty of Science and Engineering |
| Funders: |
Kingdom of Saudi Arabia - The Royal Embassy of Saudi Arabia Cultural Bureau in London |