Microwave Absorption of Multifunctional Graphene Based Polylactide Acid Composites: Experimental and Numerical Study

• Author / Creator

  Dua, Mahima

• Thermoplastic polymer piping is increasingly used in a variety of industries. Thermoplastics permit fusion bonding for the joining of pipe sections, which can be performed using joule heating. However, embedding heating wires into the plastic adds fabrication complexity and expenditure. Moreover, joule heating enables only localized heat input that requires moderation to avoid damage in polymers. Another key factor linked to failure with this joining method is joint misalignment. Microwave heating may compensate for these inadequacies, resulting in shorter fusing times, improved heating uniformity, and lower electricity use. This study explores the use of pure graphene nanoplatelets (pGNP) and functionalized GNP (fGNP) to create multifunctional polylactide acid (PLA) composites for high microwave absorption. GNP was treated with tannic acid to produce fGNP. A two-step scalable fabrication procedure, consisting of solution blending followed by hot compression molding was used to obtain the pGNP/PLA and fGNP/PLA composites. The concentration of GNP and fGNP in the composites ranged from 0 to 8 wt%. The resulting composites were characterized for their heat capacity, thermal and electrical conductivity, and complex permittivity. Thermal imaging was used to investigate the efficacy of microwave heating in pGNP/PLA and fGNP/PLA samples as a function of microwave power and filler weight fractions. Multi-physics finite element software was used to explore and simulate the microwave heating mechanism in GNP composites. The experimental results were compared to numerical model predictions for maximum temperature and microwave energy absorbed. The produced nanocomposites were found to exhibit strong microwave absorption and thus rapid heating, making this type of composite a promising candidate for gasket materials that facilitate fusion bonding in thermoplastic-based piping via localized heating.

• Subjects / Keywords

  • Microwave Heating
  • Graphene Nanocomposite
  • Thermoplastic Polymer
  • FEM
  • PLA

• Graduation date

  Fall 2022

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-h96q-6p68

• License

  This thesis is made available by the University of Alberta Library with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.