2022-11-10 オークリッジ国立研究所(ORNL)
研究チームのアプローチは、可逆的な動的共有結合を組み込むことで、炭素繊維とポリマーの両方のリサイクルを可能にするものである。この新しいポリマーは、6回の再処理サイクルで機械的強度を維持し、これまで報告されてきたポリマーとは全く対照的であった。
ORNLの炭素繊維複合材料は、高速処理が可能で、修理や再処理を何度も行うことができるため、循環型の低炭素製造への道を開くものである。
＜関連情報＞
- https://www.ornl.gov/news/recyclable-composites-help-drive-net-zero-goal
- https://www.sciencedirect.com/science/article/pii/S2666386422003307
テーラード繊維強化ビトリマー複合材料のマルチサイクルリサイクルへの道筋の解明 Unraveling a path for multi-cycle recycling of tailored fiber-reinforced vitrimer composites
Zhengping Zhou,Sungjin Kim,Christopher C.Bowland,Bingrui Li,Natasha Ghezawi,Edgar Lara-Curzio,Ahmed Hassen,Amit K.Naskar,Md Anisur Rahman,Tomonori Saito
Cell Reports Physical Science Published: August 31, 2022
DOI:https://doi.org/10.1016/j.xcrp.2022.101036
Highlights
- •Facile and scalable vitrimer design allows rapid and stable multi-cycle reprocessing
- •The tailored vitrimer CFRPs enable multi-cycle processability and repairability
- •The circular CFRP processing provides a path for low-carbon manufacturing
Summary
Manufacturing transformation toward a net-zero carbon society demands polymeric composite materials to be reprocessable in circularity in an energy-efficient and stable manner. Recent advancements in vitrimers have bestowed crosslinked polymers like epoxies with reprocessability, opening a path for the circular manufacturing of thermosets. However, (re)processing of mechanically robust vitrimers such as epoxy vitrimers typically requires high temperatures and long processing times, which cause degradation and compromise efficient recyclability. Here, we report a simple design of dynamic polyurea/epoxy (DPE) vitrimers and their carbon-fiber-reinforced polymers (CFRPs) with exchangeable disulfide crosslinks, which overcome such intrinsic limitations. Compared with conventional epoxy vitrimers, the DPE vitrimer exhibits 6 times faster bond rearrangement and ∼40°C lower reprocessing temperature, which enables full recovery of the mechanical strength throughout 6 reprocessing cycles, while the conventional vitrimer lost ∼63% of strength. Moreover, the CFRPs prepared with the DPE vitrimers exhibit facile multi-cycle processability and repairability by thermoformation.
