Date of Award
Master of Science in Mechanical Engineering (MSME)
Dr. Abdel-Hamid Ismail Mourad
Dr. Basim Abu-Jdayil
Dr. Jaber Abu Qudeiri
The main scope of this research is to develop polymer-filler thermal insulators utilizing natural and industrial local waste such as date pit powder (DPP), devulcanized tire rubber (DVR), and buffing dust (BD). Recycling and reuse of these local wastes as fillers in insulation materials has significant benefits for the UAE environment. An objective of this work was to study the effect of the combination of these local wastes with polystyrene (PS) on the physical, mechanical, and thermal properties of the developed thermal insulators. PS was used as a matrix, mixed in different proportions with the waste fillers. Each mixture was then exposed to heat and pressure in a hot press to form a solid sample. The formed composites were tested to evaluate their physical (water absorption and bulk density), mechanical (compression strength, compression modulus, tensile strength, tensile modulus, flexural strength, and flexural modulus), and thermal properties (thermal conductivity and thermogravimetric analysis (TGA)). The results established that DPP, DVR, and BD were suitable as fillers in thermal insulation materials. Use of DPP and DVR waste in ratios ranging from 0 wt. % to 30 wt. % affected thermal conductivity minimally and resulted in an acceptable reduction in mechanical properties. Replacing 50 wt. % of PS by DPP increased the thermal conductivity by only 9.1%. Adding 10 wt. % of BD to the PS reduced thermal conductivity by 13.29 %, with negligible effect on the mechanical properties. Similarly, low DVR rubber content led to a slight reduction in thermal conductivity (4 %). However, higher proportions of DVR and BD content had a negative effect on the thermal and mechanical properties. Prior treatment of the waste fillers with NaOH, enhanced mechanical performance in composites prepared from the treated fillers. Scanning electron microscopy (SEM) was used to investigate the microstructure of the prepared composites. In addition, the waste fillers were analyzed by infrared spectroscopy (FTIR) to identify the main functional groups in the fillers. To study the effect of the chemical treatment on the main functional groups, these fillers were analyzed by FTIR after the treatment. Although the addition of the three types of waste reduced mechanical strength, all prepared composites with a waste filler concentration below 30 wt. % displayed good mechanical properties, compared with available commercial thermal insulators. Moreover, replacing one-third of the thickness of a building wall with DPP-polystyrene, DVR-PS, and BD-PS composites reduced the heat transfer coefficient by 85 %, 87.8 %, and 83 %, respectively. Therefore, recycling of the local wastes DPP, BD, and DVR as filler materials in thermal insulators presents an opportunity for significant benefit to the UAE economy.
Yousef Hittini, Waseem, "DEVELOPMENT OF WASTE-BASED-THERMOPLASTIC COMPOSITE HEAT INSULATORS" (2018). Mechanical Engineering Theses. 12.