This study compared the mechanical properties of a recyclable flax fiber reinforced polymer composite (FFRP) with a covalent adaptable network (CAN) matrix to an FFRP composite with a conventional (unrecyclable) epoxy resin matrix. The results indicated that composites fabricated via vacuum-assisted resin transfer molding (VARTM) exhibited up to 19% higher tensile modulus and strength compared to those fabricated via hand layup, attributed to reduced air void content and more uniform fiber alignment. Microscopy evidence supported by mechanical property tests revealed superior adhesion of the CAN matrix to flax fibers compared to conventional epoxy resin. Additionally, a solvent-based method was demonstrated for separating fibers from the CAN matrix, facilitating reuse or upcycling.
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This content will become publicly available on May 20, 2025
Eco-Friendly Composites: Fabrication and Characterization of Polymer Composites made from Bio-Based Curing Agent
Thermoset polymer composites, known for their outstanding thermal, mechanical, and chemical properties, have found applications in diverse fields, including aerospace and automotive industries. These polymers, once cured, cannot be recycled, making the end-of-life management of these composites very difficult and posing an environmental challenge. Conventional recycling methods are unsuitable for thermosets, forcing their accumulation in landfills and raising environmental concerns. One possible solution to overcome this concern is to use resins or curing agents, or both, made from biodegradable materials. This study explores the fabrication and characterization of polymer composites using a commercially available green curing agent made from biomass. The composite laminates were fabricated using HVARTM (Heated Vacuum Assisted Resin Transfer Molding) process. In this process, heat pads are used to increase the temperature of both the epoxy resin and the plain weave carbon fiber laminate to a desired temperature, providing ease of flow to the resin. Small coupons were cut from the laminate using a water jet machine to study the flexural behavior of the composite in accordance with ASTM testing standards and compared with composite coupons fabricated using conventional epoxy resin.
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- Award ID(s):
- 2000318
- PAR ID:
- 10562699
- Publisher / Repository:
- SAMPE-North America
- Date Published:
- ISBN:
- 978-1-934551-45-5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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