Uses for Silicone Compounds in Space
Silicon-based polymers are ideal for use in a range of space and low-earth-orbit (LEO) applications. They are flexible through a wide range of temperatures, resistant to vibration and cracking, and unaffected by high vacuum. However, silicone compounds are negatively affected by radiation, subject to oxidative damage, and prone to outgassing.
Since space puts unique demands on whatever is to be used there, engineers must choose the very best material for the task at hand. Silicon polymers have always been the best choice of material for some important roles in space, and these days, new orbital applications are being developed for this versatile class of chemical compound.
Orbital materials must withstand cosmic radiation and ultraviolet light. Furthermore, in LEO, the relatively high levels of molecular oxygen make for a highly corrosive atmosphere. These adverse conditions damage most polymers, including silicone. Exposure to ionizing radiation causes silicone to lose its elasticity, then crack. Oxidation further damages the compound, leading to outgassing, a lack of vibration resistance, and eventual failure.
Scientists have developed techniques for protecting silicon-based polymers from the deleterious effects of space. Corrosion-resistant coatings, combined with new, radiation-resistant formulations make silicon the best choice of adhesive because it is capable of maintaining its viability during the rapid and extreme temperature changes experienced in orbit.
A new and potentially revolutionary use of silicon is as a replacement for the glass used in the lenses of solar power arrays. Its light weight and flexibility make it an ideal choice for engineers who are designing new solar-concentrating lenses. These lenses are flexible, allowing for lower launch volumes than conventional glass lenses. Once in orbit, they are unfurled into their final shape.
Chemical engineers are continually developing new and improved silicon compounds, and new uses for these versatile and indispensible materials.
