Six Technology Trends in Polymer Materials for The Aerospace Sector

Six Technology Trends in Polymer Materials for the Aerospace Sector

Polymers are increasingly used in aircraft and spacecraft to reduce weight, enhance quality, and lower manufacturing and maintenance costs.

1. Use of more disinfectant-compatible antimicrobial plastics for aircraft interiors.
Cleaning and disinfection methods for aircraft interior surfaces can rapidly degrade traditional plastics. New antimicrobial and disinfectant-resistant plastics, originally developed for hospital use, are now being specified for aircraft interiors. These materials are formulated to meet the stringent flame, smoke, toxicity, and heat release standards required for commercial aircraft.

2. Specifying high-strength thermoplastic composites to reduce weight and improve fuel efficiency.
Aerospace structures requiring high strength and stiffness have traditionally been made from metals or thermoset composites. However, these materials have significant limitations. Metals are heavy, restricting their use in weight-sensitive aerospace applications. Thermoset composites are often brittle, typically exhibit poor chemical resistance, and their manufacturing is labor-intensive. Most thermoset composites are unsuitable for use above 100°C.
A new class of thermoplastic composites developed by companies like Ensinger offers strength and modulus (stiffness) values comparable to metals and thermosets. This technology involves embedding continuous glass or carbon fibers into a thermoplastic polymer matrix, typically composed of Polyetheretherketone (PEEK) or Ultem PEI (Polyetherimide). Since the matrix is made from high-performance, thermally stable plastics, these composites can be used at elevated temperatures.
Thermoplastic composites offer many advantages associated with thermoplastics, including ductility, fatigue resistance, vibration damping, and resistance to fuels, lubricants, and cleaning chemicals. Sheets made from these materials can be rapidly formed into finished parts using heated metal tools, reducing manufacturing costs.

3. Selecting plastics that do not interfere with Radio Frequency (RF) signals for high-performance communication radomes.
The proliferation of Unmanned Aerial Vehicles (UAVs), drones, and satellites that rely on RF signals for flight operations has increased the demand for highly reliable antennas. Optimal antenna function requires that the plastic radome does not significantly attenuate the RF signal across the required frequency range and the device's operating temperature range. Specialized engineering plastics with low dielectric constants, low dissipation factors, and enhanced toughness, UV resistance, and thermoformability are increasingly being specified for protective antenna radomes.

4. Selecting durable high-temperature plastics to separate metal surfaces for improved reliability.
Metal-to-metal joints are often failure points in aircraft components due to inherent issues when paired metal surfaces are subjected to vibration and/or sliding wear. Designers are increasingly using tough, high-performance polyimide materials for applications like spline couplings and lock fastener anti-rotation elements to separate metal parts. Introducing a polymer element into the assembly can extend service life and prolong intervals between required maintenance.
For spline connections that transmit power via connected rotating metal shafts to various aircraft systems, high-temperature couplings made from DuPont Vespel polyimide are installed between the paired metal splines for smoother operation and longer life. This approach reduces spline wear when rotating shafts are slightly misaligned. The ductility of the polymer allows for shaft misalignment without excessive stress on the metal shafts, bearings, or drive motors.
In aerospace lock fasteners, DuPont Vespel polyimide is used as a ductile locking element in nuts or bolts to prevent unwanted rotation without damaging the mating metal fastener during assembly or disassembly for maintenance. This polymer element prevents galling associated with all-metal lock fastener designs.
In both examples, the polymer's ductility and wear characteristics mitigate problems associated with metal-to-metal contact.

5. Selecting plastics with low flammability and high dielectric strength for electrical insulation.
Plastics have long been the material of choice for applications requiring electrical insulation properties. The electrical systems of modern military and civilian aircraft are particularly challenging. Besides good dielectric strength and arc resistance, polymer insulators must also be resistant to aircraft fuels and lubricants, withstand vibration, wear, and fatigue, and possess excellent flammability performance. Plastic insulators on aircraft must also operate across a wide temperature range, from extreme cold at cruise altitudes to extreme heat near jet engines.
Aircraft electrical system designers now specify fluoropolymers like Polytetrafluoroethylene (PTFE), Fluorinated Ethylene Propylene (FEP), and Perfluoroalkoxy (PFA), along with other high-performance thermoplastics, for demanding aerospace electrical applications, including bracket insulators, heat-shrink tubing, and flexible wire insulation.

6. Adopting innovative polymers to create premium aircraft interiors.
Commercial aircraft are becoming more upscale, with interiors rivaling luxury hotel lobbies. Traditionally, printed patterns on aircraft interiors were problematic because high-traffic areas exposed to wear and repeated cleaning quickly degraded the print.
Newer technologies, like the infused imaging process for KYDEX thermoplastics, allow designers to create custom environments using images within the material, not on it.
Significant progress has also been made in plastic lens materials for managing and transmitting light onboard commercial aircraft. New polymer formulations enable high light transmittance, good diffusion, and precise color control for LED lighting. Light management using high-performance plastics is positively impacting the aesthetics of aircraft interior spaces.

In summary, polymers have become indispensable in modern aerospace technology, from high-performance composite structures to critical functional components. Particularly in safety-critical areas, the design and application of flame-retardant materials are paramount. Whether it's PA for connectors and wire insulation, or EVA for interiors and packaging, these materials must meet stringent standards for flame retardancy, low smoke, low toxicity, and excellent mechanical and environmental performance. Addressing these high-end demands, Yinsu Flame Retardant Company, leveraging its profound technical expertise, has successfully developed a series of star products such as FRP-950X and WADP-10. These materials not only possess outstanding flame retardant efficiency but also balance toughness, processability, and durability. They have been successfully applied in various key areas including aircraft interior components, electrical systems, and equipment protection, providing robust material support for enhancing the safety, reliability, and lightweight performance of aerospace vehicles.