Towards sustainable and efficient out-of-autoclave processing of fibre reinforced epoxy by frontal polymerisation
Abstract
Fiber reinforced thermoset polymers are a key component in the structure of modern aircrafts due to their excellent specific stiffness and strength, as well as fatigue resistance, and the possibility to tune mechanical, thermal, and electrical properties by an adequate choice of fiber reinforcement. Their processing route still relies on the use of pre-impregnated materials cured in high temperature and pressure autoclaves, or the use of resin impregnation followed by thermal cure, requiring several hours, and contributing to high economic and environmental impact. With the development of novel epoxy-based resin systems, which can polymerize from a localized thermal or UV-light trigger into a self-sustaining curing front, a new route to process composites can be imagined. This requires, however, to harness the complex interplay between the heat released by the fast-curing resin, and that dissipated by thermal diffusion into the reinforcing fibers and the mold. Up to now, the maximal fiber content that could be reached with these materials is below what is desired for a structural part. Preliminary work at LPAC showed great promise with an adapted resin composition and mold design, reaching up to 60percent fiber content in small composite samples. With the present project, we intend to prove that we can formulate a process whereby impregnation and frontal polymerization are optimized to reach high volume fraction composites with low void content and adequate mechanical properties. To this end, we will develop an experimental process window to reach adequate composite quality as a function of the resin formulation, mold material and complexity, together with a modelling framework to enable further predictions, once validated. We will also design a mold to demonstrate potential scaling-up of the processing route and conduct a life cycle analysis as well as economic analysis to produce a composite part with this novel process, as compared to traditional autoclave or out-of-autoclave methods.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 22, 2024
- Source ID
- FA86552317035
Entities
People
- Veronique Michaud
Organizations
- Air Force Office of Scientific Research
- Swiss Federal Institute of Technology in Lausanne
- United States Air Force