Recovery of epoxy thermosets and their composites

Wang, Chao; Long, Yuwei; Xu, Shimei; Li, Xuehui; Chen, Li; Wang, Yu‐Zhong

doi:10.1016/j.mattod.2022.12.005

Cited by 67 publications

(41 citation statements)

References 209 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Carbon fiber‐reinforced epoxy composites (CFREPCs) with light weight, superior specific strength/modulus, corrosion, and fatigue resistance have witnessed explosive development in diverse flame retardancy‐required fields, such as wind turbines, aerospace, and transportation 1,2 . The ever‐growing concerns about the environmental and resource impacts caused by the accumulation of CFREPCs wastes have urged the industry to develop the recycling techniques, such as mechanical recycling and energy recovery 3,4 . However, these conventional methods generally resulted in the recycled carbon fibers (CF) with deteriorative comprehensive performances and low energy recovery efficiency from the lower incineration efficiency of EPs, 5 particularly after flame‐retardant modification, making it harder to conquer the environmental and economic issues from the waste CFREPCs.…”

Section: Introductionmentioning

confidence: 99%

Phosphonate‐influenced Diels‐Alder chemistry toward multi‐path recyclable, fire safe thermoset and its carbon fiber composites

Lü

et al. 2023

EcoMat

Self Cite

View full text Add to dashboard Cite

Dynamic covalent chemistry offers a solution to tackle the recycling issue of epoxy resins (EPs) and their carbon fiber‐reinforced composites; however, the vulnerability to creep associated with the inflammable nature of the EPs are the key obstacles for their applications. Herein, we propose a feasible and facile strategy to overcome these obstacles by incorporating phosphorus‐influenced Diels‐Alder (DA) chemistry to construct dynamic epoxy networks. In the strategy, the electron‐withdrawing phosphonate in the dienophile maleimide greatly promotes the thermal stability of the DA reaction, exhibiting excellent creep resistance, repairability, and malleability; while its flame‐retardant activity improves the fire safety of the resultant thermosets. Meanwhile, nondestructive recycling of carbon fiber is achieved. The ease with which EP and its composites can be manufactured, used, recycled and re‐used–without losing service performance–points to new orientation in sustainable composites.image

show abstract

Section: Introductionmentioning

confidence: 99%

Phosphonate‐influenced Diels‐Alder chemistry toward multi‐path recyclable, fire safe thermoset and its carbon fiber composites

Lü

et al. 2023

EcoMat

Self Cite

View full text Add to dashboard Cite

show abstract

“…It brings excellent performance regarding the service time but at the sacrifice of recyclability after the end of life. Numerous studies have been carried out on the development of novel epoxy thermosets containing dynamic covalent bonds from the view of recovery . They are the key to balancing recovery after discard with the stability of the material during service life. − Despite this being a promising exploration, it is imperative and urgent to address the recovery issue of large quantities of existing epoxy thermoset wastes.…”

Section: Introductionmentioning

confidence: 99%

Association between Serviceability and Recyclability of Amine-Cured Epoxy Thermosets

Long,

Bai,

Liu

et al. 2023

ACS Sustainable Chem. Eng.

Self Cite

View full text Add to dashboard Cite

The dense cross-linked network not only endows epoxy thermosets with excellent performance in service time but also increases the difficulty of recycling after the end of life. A great deal of research has been dedicated to developing new methods for chemcycling epoxy thermosets. However, they are always case studies within specific types of curing agents, and it lacks understanding of the comprehensive linkage among structure, performance, and recyclability of the thermosets. Herein, we explore the relationship between service performance and oxidative recovery of widely used types of amine-cured epoxy thermosets. Besides, it is also found that the early degradation stages are mainly determined by the grades of carbon linked to the amine in the curing agent, while the mid−late stages are mainly controlled by the cross-link density. This study will provide a useful guide to the service life and recycling of amine-cured epoxy thermosets.

show abstract

“…Epoxy resins (EPs), a typical kind of thermoset polymer with a highly covalently cross-linking structure, exhibit excellent thermal and mechanical properties, chemical resistance, and electrical insulation, as well as the flexibility of many other applications, and have become an indispensable thermoset in various fields of both industry and daily life . Unlike thermoplastic polymers, once fully cured, EPs can inherently not be reshaped, reprocessed, or recycled due to their permanent cross-linking architecture, producing a significant amount of waste. , Recently, an attractive method to introduce plasticity into thermosets was offered by the introduction of reversible covalent bonds, and the resulting polymer networks were known as covalently adaptable networks (CANs) . According to different exchange mechanisms, under external stimuli, CANs can be “plasticized” in two pathways, i.e., the dissociative pathway and the associative pathway.…”

Section: Introductionmentioning

confidence: 99%

Robust Epoxy Vitrimer with Simultaneous Ultrahigh Impact Property, Fire Safety, and Multipath Recyclability via Rigid-Flexible Imine Networks

Ding,

Chen,

et al. 2023

ACS Sustainable Chem. Eng.

Self Cite

View full text Add to dashboard Cite

Vitrimers have promise as adaptable materials capable of self-healing, shape reconfigurability, and remoldability due to dynamic covalent reactions occurring above their transition temperatures; however, their relatively poor mechanical properties, particularly compared to commercially available thermosets, have limited their further application in diverse industries. Herein, we demonstrate a rigid-flexible integrated strategy for fabricating robust epoxy vitrimers (EVs) with superb mechanical properties comparable to those of conventional epoxy thermosets. The rigid aromatic Schiff base moiety and flexible siloxane spacer increased the network rigidity and molecular weight between cross-links, endowing the EVs with high strength, ultratoughness, and rapid dynamic exchange of imine bonds. The EV displayed a rarely reported ultrahigh impact strength of 61.8 kJ•m −2 and realized the recyclability of the thermosetting resin through physical reprocessing and chemical recycling. Furthermore, it broke through the restriction on the plasticity of a robust EV network greatly limited by permanent cross-links, provided a solution to the inherent contradictions between high mechanical properties and facile malleability, and repaired the deficiency of brittleness and flammability toward conventional epoxy resins without any use of conventional flame-retardant elements, such as halogens and phosphorus. EVs based on this rigid-flexible integrated strategy enormously broaden the field of their application, and it is of great significance for the recycling of damaged, aged, or discarded epoxy resin-based materials as well as resource conservation and environmental protection.

show abstract

Recovery of epoxy thermosets and their composites

Cited by 67 publications

References 209 publications

Phosphonate‐influenced Diels‐Alder chemistry toward multi‐path recyclable, fire safe thermoset and its carbon fiber composites

Phosphonate‐influenced Diels‐Alder chemistry toward multi‐path recyclable, fire safe thermoset and its carbon fiber composites

Association between Serviceability and Recyclability of Amine-Cured Epoxy Thermosets

Robust Epoxy Vitrimer with Simultaneous Ultrahigh Impact Property, Fire Safety, and Multipath Recyclability via Rigid-Flexible Imine Networks

Contact Info

Product

Resources

About