Polymer blend of Polybenzimidazole and Polyimide for downhole electronics in oil/gas fields

open_access
Open Access
Author:
Al Ahmed, Abdulelah
Area of Honors:
Interdisciplinary in Petroleum and Natural Gas Engineering & Materials Science and Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Qing Wang, Thesis Supervisor
Eugene C Morgan, Thesis Honors Advisor
Amy Carol Robinson, Thesis Honors Advisor
Keywords:
Dielectric
polymers
downhole electronics
downhole
capacitors
oil/gas
logging tools
Abstract:
The demand for energy increases rapidly each year. A sufficient and reliable energy source is imperative. To this day, fossil fuels – especially oil and gas- play a crucial role in meeting the world’s energy demand. Oil and gas extraction depends on advanced technologies that guarantee optimized exploration, enhanced efficiency, and reliable safety under harsh conditions. Downhole electronics are one example that the industry utilizes in fossil fuel extraction. Current efforts to produce equipment that can withstand high temperatures focus on the system rather than specific electronics. However, another approach might be feasible; enhancing the dielectric materials in capacitors to withstand the high temperature can be an alternative. This thesis investigated polymer blends of Polyimide (PI) and Polybenzimidazole (PBI) to assess the dielectric properties and feasibility in high-temperature capacitors. PBI was synthesized in the lab, and the PI was commercially bought. Five blends with different mass ratios were casted as polymer films. The film blends were characterized for Nuclear magnetic resonance (NMR), D-E hysteresis loop, dielectric spectroscopy, and differential scanning calorimetry (DSC). The best overall polymer blend had equal mass PI and PBI ratios (50PI/50PBI). The blend resulted in a higher dielectric constant and dissipation loss at 1 kHz, with 4.45 and 9.04×10^(-3) , respectively. Also, at room temperature the discharge energy density of 50PI/50PBI was 3.03 J/cm3 at 400 MV/m, with an efficiency of 49.5%. At 150°C, 50PI/50PBI exhibited a discharge energy density of 1.40 J/cm3 at 350 MV/m, with the highest recorded efficiency of 45.1%. Besides, the excellent thermal stability of 50PI/50PBI was illustrated using DSC. Hence, these results have proven that the blend 50PI/50PBI showcased a good dielectric behavior for high-temperature downhole electronics.