In December 2024, the r-LightBioCom project has achieved its project milestone in advancing fast-curing technologies for composite materials. An innovative resin transfer moulding (RTM) mould has been developed for frontal photopolymerization of bio-based resin systems, incorporating a vacuum infusion system assisted by microwaves. This setup enables the efficient production of sustainable composites, using bio-resins and, among others, natural fibres. This breakthrough offers a viable alternative to traditional autoclave curing, significantly reducing energy consumption and processing time while maintaining comparable mechanical properties.
Composite materials play a vital role in many industries, such as aerospace, automotive, and construction, due to their strength, lightweight properties, and versatility. However, traditional manufacturing methods, like autoclave curing, present significant challenges. These processes are energy-intensive, expensive, and time-consuming, requiring high temperatures and long curing times. Moreover, their environmental impact and limited use of sustainable materials, such as bio-resins and natural fibres, highlight the need for more efficient, eco-friendly production methods.
The r-LightBioCom project is addressing these challenges by developing bio-based high-performance composites alongside sustainable manufacturing and recycling methods. A milestone has been achieved in the area of sustainable composite manufacturing. Project partner CIDAUT, responsible for designing and optimizing new composite manufacturing processes within the r-LightBioCom project, has explored and developed innovative fast-curing technologies that utilize bio-based materials.
Innovative Resin Transfer Moulding (RTM) mould with UV Curing Technology
Project partner CIDAUT has created a mould for the resin transfer moulding process, specifically designed for the frontal photopolymerization of bio-based and eco-friendly resin systems. Additionally, it features a vacuum infusion system supported by microwaves. For testing and validation purposes, project partner AEP Polymers formulated customized bio-based formulations using epoxy resins and diluents obtained from widely available natural sources, balancing viscosity, reactivity and thermal properties of the final polymeric matrix. Meanwhile, project partner AITEX analysed and selected different types of fibres considering mechanical performance, environmental impact, processability and cost-effectiveness, and provided the corresponding fabrics. Using these materials, the process successfully produced high-quality composite materials, demonstrating its effectiveness.
This newly developed RTM mould with UV curing technology offers a faster, more efficient, and more sustainable alternative to conventional autoclave manufacturing, while still maintaining the high mechanical strength, durability, and lightweight properties of the produced composites. While conventional autoclave processes can take up to several hours, the RTM mould with UV curing technology achieves curing in a fraction of the time. Furthermore, it demonstrates substantial improvements in both energy efficiency and environmental impact. With energy consumption of 4,200 MJ and CO2 emissions of 380 kg per cycle, it achieves a 72% reduction in energy use and CO2 output compared to conventional autoclave methods[1]. Additionally, the integration of bio-resins and natural fibres into the RTM mould meets the growing demand for sustainable composite materials. This innovation holds significant potential for industries such as aerospace and automotive, where efficiency, performance, and environmental compliance are essential.
Innovative Microwave Process Curing
In parallel, CIDAUT developed another fast-curing technology: An innovative microwave curing process, which offers a more efficient and sustainable alternative to traditional curing processes, like the autoclave curing. By utilizing microwave energy to heat the resin, this newly developed microwave curing process addresses the challenge of poor thermal conductivity in polymers, while ensuring high mechanical strength, durability, and lightweight properties, which is essential for high-performance composites. During the curing process, the resin absorbs the microwaves, generating heat that accelerates the crosslinking of bio-monomers, resulting in a faster curing process and significantly reduced cycle times[2] compared to conventional methods. Another major advantage is that, unlike traditional curing techniques, which can be influenced by factors such as humidity or temperature, this microwave-based curing process is independent from environmental conditions, offering greater reproducibility and control and ensuring consistent results every time.
[1] Compared to a traditional autoclave process, which consumes 15,000 MJ of energy and results in 1,350 kg of CO2 emissions per cycle
[2] With an energy consumption of just 1 MJ and a time reduction of 15 to 20 minutes, the process is not only faster but also far more efficient and sustainable than traditional infusion or autoclave techniques.
