The 1958 US Space Act stipulated that NASA's research and advancements should benefit all people. As a result, many items we now use daily are a direct result of space technology innovation (e.g. scratch-resistant lenses, cord-less tools, satellite communication, etc.). It also resulted in a vast array of chemical innovations. DalinYebo's mentor, Dr. Karl Joachim Zeitsch, was part of the team that developed the hypergolic fuel chemistry for the RD4 thrusters used for the navigation of the Apollo Command Module and the Lunar Lander. Karl was also involved in the heat-shield development and its testing.
Furfuryl Alcohol and the Space Shuttle
Furfuryl Alcohol ("FA") was used in the Reinforced Carbon-Carbon (RCC) composite materials, which was developed to protect the shuttle around its nose and wing leading edge, where extremely high temperatures (>1,260°C) were encountered during the shuttles re-entry into the atmosphere.
Through pyrolysis, and after the graphite fabric has been rough trimmed, the polymer resin is converted into carbon which is then impregnated with furfuryl alcohol. The density of this material is increased by further pyrolysis, which also leads to improved mechanical properties[1].
An Industrial Renaissance
In our "New Agricultural Economy" article, we made reference to the furfural knowledge that has been developed in Durban (South Africa) since the 1970s. Besides the generation that has retired, there is also a generation of scientists and engineers that have left the industry, as a result of the limited opportunities or a lack of research funding (see "Drop-in Pothole Repairs"). However, these professionals are still available to share their knowhow.
One of the unique properties of furfural alcohol is its use to create really long-chain polymers ..
.. on its own or with other compounds. This chemistry was well researched already in the last century ( .. and almost forgotten), but very little of it is used commercially today. Conceptually similar to the process used by the NASA engineers, FA is used to penetrate cell structure of natural materials:
FA is used to impregnate the cells of wood, where is polymerised and bonded with the wood. The treated wood has improved moisture-dimensional stability, hardness, and decay and insect resistance (see dalinyebo.com/tag/Kebony).
In a similar way, new natural co-polymers are created that find its commercial use in structural panels for the aviation or automotive industries (see dalinyebo.com/bioresins-for-fiber-reinforced-bioplastics)
Today, the bulk of the FA is used for the manufacture of furan resins, mainly used in the foundry industry (also suitable for 3D printing).
Furan resins have excellent chemical, solvent, and temperature resistance. Their use is limited, as furan coatings are brittle, show poor adhesion to nonporous surfaces (such as steel), and show high shrinkage on curing. However, there is unexploited research that shows how a copolymer can over-come some of these limitations.
Reference
[1] Space Shuttle and Furfuryl Alcohol and Materials Used in Space Shuttle Thermal Protection Systems
