Frontal Polymerizations: From Chemical Perspectives to Macroscopic Properties and Applications

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(6), P. 3237 - 3298

Published: Feb. 24, 2023

The synthesis and processing of most thermoplastics thermoset polymeric materials rely on energy-inefficient environmentally burdensome manufacturing methods. Frontal polymerization is an attractive, scalable alternative due to its exploitation heat that generally wasted unutilized. only external energy needed for frontal initial thermal (or photo) stimulus locally ignites the reaction. subsequent reaction exothermicity provides local heating; transport this neighboring monomers in either a liquid or gel-like state results self-perpetuating zone fully cured thermosets thermoplastics. Propagation front continues through unreacted monomer media until all reactants are consumed sufficient loss stalls further Several different mechanisms support processes, including free-radical, cat- anionic, amine-cure epoxides, ring-opening metathesis polymerization. choice monomer, initiator/catalyst, additives dictates how fast polymer traverses reactant medium, as well maximum temperature achievable. Numerous applications frontally generated exist, ranging from porous substrate reinforcement fabrication patterned composites. In review, we examine detail physical chemical phenomena govern polymerization, outline existing applications.

Language: Английский

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High-strength, self-reinforcing and recyclable multifunctional lignin-based polyurethanes based on multi-level dynamic cross-linking

Chemical Engineering Journal, Journal Year: 2023, Volume and Issue: 473, P. 145423 - 145423

Published: Aug. 12, 2023

Language: Английский

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Dynamic Interfaces in Self-Healable Polymers

Langmuir, Journal Year: 2024, Volume and Issue: 40(14), P. 7268 - 7285

Published: Feb. 23, 2024

It is well-established that interfaces play critical roles in biological and synthetic processes. Aside from significant practical applications, the most accessible measurable quantity interfacial tension, which represents a measure of energy required to create or rejoin two surfaces. Owing fact processes are polymeric materials, this review outlines recent advances dynamic involving physics chemistry targeting self-healing. Entropic energies stored during damage participate recovery, self-healing depends upon copolymer composition monomer sequence, molar ratios, molecular weight, polymer dispersity. These properties ultimately impact chain flexibility, shape-memory interactions. Self-healing localized process with global implications on mechanical other properties. Selected examples driven by flow shape memory effects discussed context covalent supramolecular rebonding self-healable materials development.

Language: Английский

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Solvent‐Free, Degradable Resins for 3D Inkjet Printing Based on Silyl Ether and Amino Acid Phosphoramide Photomonomers

Macromolecular Materials and Engineering, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 27, 2025

Abstract Inkjet 3D printing is a fast, reliable and noncontact method, capable of producing small large structures enabling multi‐material printing. These characteristics make inkjet an excellent technique for additive manufacturing biomaterials, such as scaffolds tissue engineering. However, the technology restricted by limited number suitable photopolymers which hitherto are to acrylate‐based chemistries, not only toxic but nondegradable, thus use in many biomaterials‐based applications. Herein, unique innovative approach described looking beyond traditional carbon‐based chemistry design synthesize novel photomonomers based on amino acid phosphoramides (APA) with silyl ethers utilizing thiol‐yne click chemistry. The inks specifically designed solventless biomaterials shown be biocompatible having fast tunable degradation rates. This makes these promising material biomedical applications, regeneration.

Language: Английский

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Thermally Robust yet Deconstructable and Chemically Recyclable High‐Density Polyethylene (HDPE)‐Like Materials Based on Si−O Bonds

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(51)

Published: Oct. 30, 2023

Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into backbone of PE, it possible to produce deconstructable PE derivatives; date, however, such designs have primarily relied on carbonyl- and olefin-related functional groups. Bifunctional silyl ethers (BSEs; SiR2 (OR'2 )) could expand scope mimics as they possess strong Si-O facile chemical tunability. Here, we report BSE-containing high-density polyethylene (HDPE)-like materials synthesized through a one-pot catalytic ring-opening metathesis polymerization (ROMP) hydrogenation sequence. The crystallinity these can be adjusted by varying BSE concentration or steric bulk Si-substituents, providing handles control thermomechanical properties. Two methods for recycling HDPE are introduced, including circular approach that leverages acid-catalyzed bond exchange with 1-propanol. Additionally, despite fact starting were chain-growth (ROMP), show recover molar mass dispersity recycled products using step-growth formation exchange, generating high molecular weight mechanical properties similar commercial HDPE.

Language: Английский

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Reprocessability in Engineering Thermosets Achieved Through Frontal Ring‐Opening Metathesis Polymerization

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(28)

Published: April 23, 2024

While valued for their durability and exceptional performance, crosslinked thermosets are challenging to recycle reuse. Here, inherent reprocessability in industrially relevant polyolefin is unveiled. Unlike prior methods, this approach eliminates the need introduce exchangeable functionality regenerate material, relying instead on preserving activity of metathesis catalyst employed curing reaction. Frontal ring-opening polymerization (FROMP) proves critical activity. Conditions controlling catalytic viability explored successfully reclaim performance across multiple generations thus demonstrating long-term reprocessability. This straightforward scalable remolding strategy poised widespread adoption. Given anticipated growth thermosets, these findings represent an important conceptual advance pursuit a fully circular lifecycle thermoset polymers.

Language: Английский

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Soft‐Rigid Construction of Mechanically Robust, Thermally Stable, and Self‐Healing Polyimine Networks with Strongly Recyclable Adhesion

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 11, 2024

Abstract Reversible and recyclable thermosets have garnered increasing attention for their smart functionality sustainability. However, they still face challenges in balancing comprehensive performance dynamic features. Herein, silicon (Si)─oxygen (O) imidazole units covalent bonds are coupled to generate a new class of bio‐polyimines (Bio‐Si‐PABZs), endow them with high excellent reprocessing capability acid‐degradability. By tailoring the molar content diamines, this Bio‐Si‐PABZs displayed both markedly glass transition temperature (162 °C) char yield at 800 °C an oxygen atmosphere (73.1%). These favorable properties outperformed various previously reported polyimines competed effectively commercial fossil‐based polycarbonate. Moreover, scratch (≈10 µ m) on surface samples can be self‐healing within only 2 min, effective “ Bird Nest ”‐to‐“ Torch ” recycling also achieved through free amines solution. Most importantly, bio‐based siloxane adhesive derived from intermediate Bio‐Si‐PABZ‐1 by acidic degradation demonstrated broad robust adhesion substrates, values reaching up ≈3.5 MPa. For first time, study lays scientific groundwork designing polyimine Si─O units, as well converting plastic wastes into thermal‐reversibility renewable adhesives.

Language: Английский

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Thermally Robust yet Deconstructable and Chemically Recyclable High‐Density Polyethylene (HDPE)‐Like Materials Based on Si−O Bonds

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 135(51)

Published: Oct. 30, 2023

Abstract Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into backbone of PE, it possible to produce deconstructable PE derivatives; date, however, such designs have primarily relied on carbonyl‐ and olefin‐related functional groups. Bifunctional silyl ethers (BSEs; SiR 2 (OR′ )) could expand scope mimics as they possess strong Si−O facile chemical tunability. Here, we report BSE‐containing high‐density polyethylene (HDPE)‐like materials synthesized through a one‐pot catalytic ring‐opening metathesis polymerization (ROMP) hydrogenation sequence. The crystallinity these can be adjusted by varying BSE concentration or steric bulk Si‐substituents, providing handles control thermomechanical properties. Two methods for recycling HDPE are introduced, including circular approach that leverages acid‐catalyzed bond exchange with 1‐propanol. Additionally, despite fact starting were chain‐growth (ROMP), show recover molar mass dispersity recycled products using step‐growth formation exchange, generating high molecular weight mechanical properties similar commercial HDPE.

Language: Английский

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Reprocessable Polyurethane Foams Using Acetoacetyl-Formed Amides

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 2, 2023

Like any other thermosetting material, polyurethane foams (PUFs) contain permanent cross-links that hinder their reprocessability and make recyclability a tedious environmentally unfriendly process. Herein, we introduce acetoacetyl-formed amides, formed by the reaction of isocyanates with acetoacetate groups, as dynamic units in backbone PUFs. By extensive variation foam composition, optimum parameters have been found to produce malleable above temperatures 130 °C, without requirement solvent during foaming The PU cross-linked material can be compression-molded at least three times, giving rise elastomers thus maintaining network structure. Characterization original shows comparable properties standard PUFs, for example, having density 32 kg/m3, while they show similar chemical thermal upon reprocessing strong elastomers, exhibiting Tg ranging from −42 −48 °C. This research provides straightforward method thermally reprocessable PUFs promising pathway address recycling issues end-of-life foams.

Language: Английский

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Facile Approach for the Preparation of Robust and Thermally Stable Silyl Ether Cross-Linked Poly(ethylene-vinyl acetate) Vitrimers

ACS Applied Polymer Materials, Journal Year: 2023, Volume and Issue: 5(10), P. 8379 - 8386

Published: Sept. 11, 2023

Vitrimers as an emerging class of dynamic polymer networks hold great promise for the development sustainable thermosets. While straightforward method to prepare vitrimers from commodity polymers is cost-competitive, most studies involved synthesis with specific functional groups and/or crosslinkers. Herein, we demonstrated a simple and scalable approach produce poly(ethylene-vinyl acetate) (EVA) by direct cross-linking industrial EVA product commercial bis[3-(trimethoxysilyl)propyl]amine using titanium(IV) butoxide catalyst through reactive blending. Incorporation thermally stable silyl ether cross-links into network led significantly enhanced thermal mechanical properties. Compared original EVA, resulting showed up 4 2 times improvement in Young's modulus tensile strength, respectively. The creep resistance vitrimer increased density, notably, EVA-V0.8 displayed low permanent deformation 1.2% at high temperature 180 °C, much higher than normal service temperature. Moreover, excellent reprocessability recyclability, modulus, elongation break were nearly identical even after four recycling.

Language: Английский

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