Pili nut is common in the Philippines, especially in the Bicol region. It is a favorite crispy snack, or as an ingredient in dishes. It is also currently being used in cosmetics.
Another part of the pili tree will soon become popular through the innovative research by a former Aeronautics Engineering student.
The pili tree resin was used in a research for an aircraft sealant by Mark Kennedy Bantugon, which made him the Philippine National Winner in the 2021 James Dyson Award. The 28 national winners were chosen from the best young inventors from over 2,000 entries from 28 countries and regions.
The Philippine State College of Aeronautics graduate, Bantugon turned the waste of pili tree resin, also called as “spent resin” or “de-oiled resin,” into Pili Seal as sealant for aircraft integral fuel tank.
He began his research on the applications of natural tree resin when he was still in high school at Batangas National High School and continued it in college.
He explored his study on the pili tree resin as an alternative to the polysulfide-based sealant that is commonly used by the aircraft industry for sealing fuel tanks.
“This product is beneficial and effective for aircraft parts application like integral fuel tank that serves as a sealing material to avoid the fuel leakage. Unlike the commercial sealant, it offers safe and nontoxic effects to user’s health based on toxicity test,” the Dyson web site said.
Polysulfide-based sealant is the first aerospace sealant which have been used by the aircraft industry for over 50 years and currently used by the manufacturers that serve as resistant to aviation fuels and are therefore useful for sealing fuel tanks.
However, the commercial sealant was deemed hazardous on several counts based on the Hazard Statement under Section III of Material Safety Data Sheet due to its chemical compositions.
Bantugon’s Pili Seal, Dyson said, is a two-component sealant that serves as the base ingredient for aircraft integral fuel tank sealant production.
It can be applied for specific aircraft parts particularly the integral fuel tank and other areas subject to contact with aircraft fuels, lubricants, oils, water and/or weathering.
As a two-component sealant, the base ingredient and hardener material are mixed in order for the sealant to work and function as a sealing material.
Admatel tests; intricate research
Bantugon sought the assistance of Advanced Device and Materials Testing Laboratory (Admatel), a Department of Science and Technology national testing laboratory, for his intricate research in January 2020, Admatel said in its web site.
His research design and procedures is composed of two parts. The Optimization Process will get the suitable and best formulation of sealant through Flammability Test, which is an important test required by the Air Laws and Regulations particularly the 14 Code of Federal Regulation Appendix.
In the Characterization Process, both Pili Seal and the commercial sealant underwent 20 different standard tests—Organoleptic Test (Color, Odor and Appearance Test), Instrumental Color Measurement Test, Flash Point Test, Tack-Free Time Test, Curing Time Test, Toxicity Test, Shore A Hardness Test, Shear Strength Test, Tensile Strength, Tear Strength Test, Peel Strength Test, Knife Test, Pull-off Test, Thermogravimetry-Differential Thermal Analysis Test, Differential Scanning Calorimetry Test, Calorific Value Test, and Viscosity Test to analyze its material properties, including the physical, chemical, mechanical, thermal and rheological properties.
“The result shows that the Pili Seal material properties are far more effective as aircraft integral fuel tank sealant in comparison to the commercial sealant,” Dyson said.
Admatel said it took Bantugon 38 formulations before he could proceed to the next part of his study, citing how the rigorous process has also impacted his final year in the university.
“I attended my classes from 7 [am] to 2 [pm] then after my class at 5 pm to 11 pm I stay up at school to formulate everyday… Even on weekends, I work from 7 o’clock in the morning until 11 at night. This is how I dedicate myself to my research,” Admatel quoted him.
With his hard work, he was able to advance to the next part of the study: to subject the experimental sealant to different standard testing to prove its effectiveness, Admatel added.
An important aspect to consider was the thermal property of the sample. It used Admatel’s Thermogravimetric-Differential Thermal Analysis (TG-DTA) and Differential Scanning Calorimetry (DSC).
DSC reveals the melting point of the sealant, while DTA reveals the thermal stability and/or degradation temperature.
Bantugon was able to identify the thermal properties of his experimental sealant to prove its stability in the application procedure.
After 10 months, 38 formulations, 20 different standard testing, nine laboratory consultations and 43 overall competitors, Bantugon finished his research.
The project first earned him the Alfredo M. Yao Intellectual Property (AMY IP) Awards Collegiate Winner in 2020.
“I did not expect to win [the AMY IP award]. I am still speechless thinking about how all of this happened, how it ended this smooth, this successful. [I] just trusted the process. I really worked hard to give a good ending and journey to my research,” he said in Filipino.
The AMY IP Awards body, through the Intellectual Property Office of the Philippines and the Philippine Chamber of Commerce and Industry, are working together to have Bantugon’s research patented and eventually test its application.
The research also won for Bantugon the Grand Champpion (Cardinal Innovator)-Cardinal Challenge 2021, Mapua Design and Innovation Competition.
The innovative Pili Seal is considered a pioneering study in the aviation industry.
Since it uses the waste material as the main ingredient in formulating sealant, Dyson said it is cheaper and affordable compared to commercially available sealants in aviation.
In analyzing its application and effectiveness, Bantugon’s product “exceeded all the data results of the commercial sealant used in aircraft integral fuel tank including the physical, chemical, mechanical, thermal and rheological property tests.”
“One of the unique features of this innovation is that it offers safe and nontoxic effects to the user’s health including the aircraft mechanics and technicians since this product undergone Toxicity Test,” Dyson said.
Moreover, this sealant displays “assured qualities and performance because it undergone 20 different standard tests.”
Bantugon plans to make further study for the application of the sealant on the other aircraft parts or different sectors [like construction, building, wood, metal sheet roof] to maximize its use and function.
He said this innovation can be used to build a manufacturing company of aviation sealants in the Philippines since the country only import aviation sealants from other countries.
“Through this goals and vision, it can help our local farmers to have new job opportunities and income because they will play a vital role in manufacturing this aviation sealant including the plantation of pili tree and extraction of its resin which is needed for sealant production,”Bantugon said.