Thermosetting Polymer Modified Asphalts: Current Status and Challenges

Polymer Reviews, Journal Year: 2023, Volume and Issue: 64(2), P. 690 - 759

Published: Nov. 30, 2023

Thermosetting polymers have higher heat resistance, chemical mechanical characteristics and structural integrity than thermoplastic due to their three-dimensional networks of covalent bonds. The current status challenges in the field thermosetting polymer modified asphalts are reviewed this article. Firstly, classification application briefly introduced, modification approaches compared. Crucial factors selecting for asphalt then analyzed. Further, cure mechanisms, preparation methods properties polymers, including epoxy resin, polyurethane, polyurea, unsaturated polyester phenolic furan resin amino discussed. Especially, effect components polyurethane on is described. To develop eco-friendly sustainable materials, article also reviews use bio-based modification. Finally, self-healing recyclable highlighted as promising solution healability recyclability after long-term service.

Language: Английский

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C–H Functionalization of Polyolefins to Access Reprocessable Polyolefin Thermosets

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(50), P. 27450 - 27458

Published: Dec. 11, 2023

Upcycling plastic waste into reprocessable materials with performance-advantaged properties would contribute to the development of a circular plastics economy. Here, we modify branched polyolefins and postconsumer polyethylene through versatile C–H functionalization approach using thiosulfonates as privileged radical group transfer functionality. Cross-linking functionalized polytopic amines provided dynamically cross-linked polyolefin networks enabled by associative bond exchange diketoenamine A combination resonant soft X-ray scattering grazing incidence revealed hierarchical phase morphology in which diketoenamine-rich microdomains phase-separate within amorphous regions between crystallites. The dynamic covalent cross-links microphase separation results useful improved mechanical properties, including ∼4.5-fold increase toughness, reduction creep deformation at temperatures relevant use, high-temperature structural stability compared parent polyolefin. nature provides stress relaxation elevated temperatures, iterative reprocessing polymer network little cycle-to-cycle property fade. ability convert thermoformable material attractive thermomechanical additional optionality for upcycling enable future circularity.

Language: Английский

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Thermally Latent Bases in Dynamic Covalent Polymer Networks and their Emerging Applications

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(24)

Published: March 14, 2023

A novel strategy allowing temporal control of dynamic bond exchange in covalently crosslinked polymer networks via latent transesterification catalysts is introduced. Obtained by a straightforward air- and water-tolerant synthesis, the catalyst designed for an irreversible temperature-mediated release strong organic base. Its long-term inactivity at temperatures below 50 °C provides unique opportunity to equip covalent with creep resistance high bond-exchange rates, once activated. The presented thermally base conveniently introducible readily available building blocks and, as proof concept, applied radically polymerized thiol-ene network. Light-mediated curing used 3D-printing functional objects, on which possibility spatially controlled reshaping welding based illustrated. Since activated, limitations regarding sample geometry optical transparency do not apply, facilitates transfer well-established industrial technologies. Consequently, fiber-reinforced highly filled magneto-active composites are fabricated thermal approach. on-demand activation demonstrated (magneto-assisted) experiments, highlighting wide range potential future applications offered concept.

Language: Английский

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A Critical Review of Sustainable Vanillin-modified Vitrimers: Synthesis, Challenge and Prospects

Reactions, Journal Year: 2023, Volume and Issue: 4(1), P. 66 - 91

Published: Jan. 2, 2023

Nearly 90% of thermosets are produced from petroleum resources, they have remarkable mechanical characteristics, chemically durable, and dimensionally stable. However, can contribute to global warming, depletion reserves, environmental contamination during manufacture, use, disposal. Using renewable resources form thermosetting materials is one the most crucial aspects addressing aforementioned issues. Vanillin-based raw been used in industrial manufacturing polymer because simple modify structurally. Conversely, traditional as a broad class high-molecular-weight molecules challenging heal, decompose recover owing their permanent 3-D crosslinking network. Once products damaged, recycling issues could arise, causing resource loss impact. It be solved by inserting dynamic covalent adaptable networks (DCANs) into chains, increasing product longevity, minimizing waste. also improves attractiveness these prospective field. Moreover, it essential underline that lifespan reducing waste equivalent expense consuming resources. The detailed synthesis, reprocessing, thermal, characteristics partly entirely biomass polymers made vanillin-modified monomers covered current work. Finally, review highlights benefits, difficulties, application emerging vitrimers potential replacement for conventional non-recyclable thermosets.

Language: Английский

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Recycling of flame retardant polymers: Current technologies and future perspectives

Journal of Material Science and Technology, Journal Year: 2024, Volume and Issue: 199, P. 156 - 183

Published: March 28, 2024

Polymers are indispensable to humans in different applications due their ease of manufacturing and overall performance. However, after a material lifetime, there is large amount polymer-based waste, which greatly contributes the loss valuable resources environmental pollution. Thermoplastics may be readily recycled, but because flammability, amounts flame retardant (FR) additives required for many applications. This results significant volume FR polymeric wastes too, particularly halogenated plastics, subject severe recycling regulations. In general, thermoplastics containing FRs raising concerns, as effective strongly influenced by chemical composition, additive content, physicochemical characteristics waste stream. The thermosets even more challenging crosslinked cured nature, makes them resistant melting reprocessing. cases, traditional mechanical methods, such grinding melting, not applicable thermosetting polymers. Current methods do always consider recovery thermosetting/thermoplastic matrix presence toxic polymer network. Sorting solvent washing treatment important steps, usually performed before reduce contamination following steps. Considering all technical difficulties during recycling, high cost sorting washing, increasing demand sustainable procedures, scientific community fostering transformation toward feasible energy-efficient strategies. Also, directives imposing strict disposal rules, limiting use halogen-based compounds, promoting commercialization recyclable review aims provide general overview currently applied approaches thermosets, possible designing next generation materials. existing strategies polymers summarized. Developments covalent adaptable networks an outlook towards circularity also addressed this review.

Language: Английский

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