REPAIRABILITY OF FIBER-REINFORCED POLYMER COMPOSITE USING BIO-BASED VITRIMERS
Topic(s) : Special Sessions
Co-authors :
Bharath RAVINDRAN (AUSTRIA), Michael FEUCHTER , Ewald FAUSTER (AUSTRIA)Abstract :
Composites derived from renewable resources are gaining attention and significance as an economic and ecological substitute for conventional composites made from synthetic fibers and matrix materials derived from petrochemicals. Given the well-established use of epoxy thermosets in diverse functional and structural applications, considerable focus has been placed on the creation of a compatible bio-based epoxy resin. Nevertheless, the thermosetting characteristic of bio-based epoxy systems poses a significant challenge, as it renders them unsuitable for conventional reprocessing, repairing, or recycling methods typically employed for thermoplastics. This limitation raises serious concerns regarding the extended efficiency of these materials and challenges in managing their end-of-life scenarios.
In order to meet the demands of green chemistry and circular economy, bio-based precursors have been progressively integrated into transesterification vitrimers [1]. As a result, increasingly superior bio-based vitrimers have been created. Specifically, many bio-based platforms—such as lignin [2] epoxidized linseed oil [3] and epoxidized soybean oil [4] have joined the vitrimer market as substitute feedstock to create more reversible and sustainable material systems.
In this study, a fully bio-based thermoset derived from epoxidized linseed oil (ELSO) is employed to manufacture a fiber-reinforced polymer (FRP) composite, utilizing distinct curing agents: anhydride and acid. The primary objective of this research is to introduce suitable characterization techniques for the quantitative assessment of the healing effectiveness of the matrix within the composites. Most mechanical test methods such as tensile or impact tests are dominated by the fibrous reinforcement, whereas three-point bending and Interlaminar Shear Strength (ILSS) term methods dominated by the polymer matrix. As a result, the vitrimer composites undergo a three-point bending test, and damaged composite samples then undergo a repair process utilizing temperature and pressure to trigger the vitrimeric behavior (self-healing). Finally, three-point bending tests are conducted on both undamaged and healed samples, thereby evaluating the efficiency of the repair process. Preliminary results indicate successful restoration of the damage as the repaired specimen regain over 91% of its ultimate strength in compression after impact tests.
In order to meet the demands of green chemistry and circular economy, bio-based precursors have been progressively integrated into transesterification vitrimers [1]. As a result, increasingly superior bio-based vitrimers have been created. Specifically, many bio-based platforms—such as lignin [2] epoxidized linseed oil [3] and epoxidized soybean oil [4] have joined the vitrimer market as substitute feedstock to create more reversible and sustainable material systems.
In this study, a fully bio-based thermoset derived from epoxidized linseed oil (ELSO) is employed to manufacture a fiber-reinforced polymer (FRP) composite, utilizing distinct curing agents: anhydride and acid. The primary objective of this research is to introduce suitable characterization techniques for the quantitative assessment of the healing effectiveness of the matrix within the composites. Most mechanical test methods such as tensile or impact tests are dominated by the fibrous reinforcement, whereas three-point bending and Interlaminar Shear Strength (ILSS) term methods dominated by the polymer matrix. As a result, the vitrimer composites undergo a three-point bending test, and damaged composite samples then undergo a repair process utilizing temperature and pressure to trigger the vitrimeric behavior (self-healing). Finally, three-point bending tests are conducted on both undamaged and healed samples, thereby evaluating the efficiency of the repair process. Preliminary results indicate successful restoration of the damage as the repaired specimen regain over 91% of its ultimate strength in compression after impact tests.