Thermally Robust yet Deconstructable and Chemically Recyclable High‐Density Polyethylene (HDPE)‐Like Materials Based on Si−O Bonds DOI Creative Commons
Alayna M. Johnson,

Jeremiah A. Johnson

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(51)

Опубликована: Окт. 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.

Язык: Английский

Recycling of flame retardant polymers: Current technologies and future perspectives DOI Creative Commons
Aurelio Bifulco, Jiuke Chen, Arvindh Sekar

и другие.

Journal of Material Science and Technology, Год журнала: 2024, Номер 199, С. 156 - 183

Опубликована: Март 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.

Язык: Английский

Процитировано

16
Biobased, reprocessable, self-blown non-isocyanate polyurethane foams: Influence of blowing agent structure and functionality DOI Creative Commons
Nathan S. Purwanto, Yixuan Chen, John M. Torkelson

и другие.

European Polymer Journal, Год журнала: 2024, Номер 206, С. 112775 - 112775

Опубликована: Янв. 19, 2024

Язык: Английский

Процитировано

15
Polypropylene-based transesterification covalent adaptable networks with internal catalysis DOI
Yuanchu Gao, Hui Niu

Polymer Chemistry, Год журнала: 2024, Номер 15(9), С. 884 - 895

Опубликована: Янв. 1, 2024

With neighboring group participation, polypropylene-based transesterification covalent adaptable networks were facilely prepared via the reaction of maleic anhydride grafted polypropylene and diol without using external catalysts.

Язык: Английский

Процитировано

10
Oligosiloxane-Based Epoxy Vitrimers: Adaptable Thermosetting Networks with Dual Dynamic Bonds DOI
Amelia A. Putnam‐Neeb,

Alex Stafford,

Sachin Babu

и другие.

ACS Applied Polymer Materials, Год журнала: 2024, Номер unknown

Опубликована: Фев. 7, 2024

Embedding dynamic covalent bonds into polymer compositions transforms static thermosets active materials with the reprocessability of thermoplastics and bulk properties cross-linked networks. This class next-generation materials, called adaptable networks, shows significant promise in composites, soft optoelectronics, robotics. Herein, we synthesized two oligosiloxane-based epoxy networks that provide fast bond exchange. Oligosiloxane diepoxides were cured stoichiometric amounts 1,2-phenylenediacetic acid to generate bonding mechanisms. The resulting provided access stress-relaxation times (1–10 min) at temperatures only 130 °C excellent reprocessability.

Язык: Английский

Процитировано

10
Dynamic covalent adhesives and their applications: Current progress and future perspectives DOI
Zhipeng Liu, Ying Tang, Yuxuan Chen

и другие.

Chemical Engineering Journal, Год журнала: 2024, Номер 497, С. 154710 - 154710

Опубликована: Авг. 13, 2024

Язык: Английский

Процитировано

10
Closed-Loop Recyclable, Self-Catalytic Transesterification Vitrimer Coatings with Superior Adhesive Strength, Fire Retardancy, and Environmental Stability DOI
Cheng Wang, Guofeng Ye,

Qi Zhang

и другие.

ACS Materials Letters, Год журнала: 2024, Номер 7(1), С. 210 - 219

Опубликована: Дек. 13, 2024

The nondegradability, nonreusability, and flammability of epoxy coatings have brought serious environmental safety issues. Herein, a multifunctional, fire-retardant vitrimer coating (DCNC/45PETO) was prepared via curing bis(2,3-epoxypropyl)cyclohex-4-ene-1,2-dicarboxylate (DCNC) with well-designed phosphaphenanthrene-containing polyethylenimine (PETO) at room temperature. DCNC/45PETO exhibits excellent adhesion to different substrates, high adhesive strength 7.9 MPa on wood, outperforming previous wood coatings/adhesives. endows fire retardancy, including limiting oxygen index 34.0% vertical burning (UL-94) V-0 rating. demonstrates durable performances in harsh environments. self-catalytic transesterification within the network effectively avoids application extra toxic catalysts, this can be reused for least 5 times mild conditions without compromising its performances. This study provides an innovative design strategy creating multifunctional coatings, showing great potential construction field.

Язык: Английский

Процитировано

9
Epoxy vitrimers: from essence to utility DOI

H. Supriya,

Sandeep Tripathi, Neetika Singh

и другие.

International Polymer Processing, Год журнала: 2025, Номер unknown

Опубликована: Янв. 20, 2025

Abstract Concerns about the effect on environment and non-renewable nature of plastics have sparked a substantial field study towards creation recyclable polymers. Vitrimers are potential class reusable polymers that recently attracted lot interest. Like conventional thermosets in strength, durability, chemical resistance, these materials offer added benefit being at end their useful life. Their structure, which includes dynamic covalent crosslinks to provide stability while enabling reprocessing, is credited with this special characteristic. We lay out an overview recent developments applications epoxy based vitrimeric by using different types adaptable networks (CANs) – single, dual triple paper attention design tactics make it easier create circular future. Covalent Adaptable Networks (CAN), novel polymer family can bridge gap between thermoplastics, emerged years uses chemistry crosslinked networks. The was enhanced 2011 Leibler colleagues when they introduced notion vitrimers, retain integrity network even after heating allow connections be reallocated within them associative exchange reactions. This review also demonstrates how vitrimer community paying need for sustainable material development demonstrating use biobased building blocks synthesis high-performing vitrimers. Having outlined primary characteristics commercialization vitrimers emphasized portray benefits self-healing, malleability, orthogonal processability, various shape memories along solutions synthetic materials.

Язык: Английский

Процитировано

1
Time–Temperature Superposition of Polybutadiene Vitrimers DOI
Ralm G. Ricarte, Sachin Shanbhag, Dana Ezzeddine

и другие.

Macromolecules, Год журнала: 2023, Номер 56(17), С. 6806 - 6817

Опубликована: Авг. 16, 2023

A vitrimer has covalent cross-links that preserve network connectivity but permit topology fluctuations through dynamic exchange reactions. In this work, we investigate the linear rheology of polybutadiene (PB) vitrimers bearing via dioxaborolane metathesis. PB are cross-linked in solution using photoinitiated thiol-ene click chemistry. As targeted cross-link density is increased, both insoluble fraction and glass-transition temperature increase. Linear viscoelasticity studied a combination small-amplitude oscillatory shear (SAOS), creep, stress relaxation measurements. SAOS, elastic modulus approximately constant while viscous increases as angular frequency decreases. compliance displays power law behavior persists for at least 8 h. relaxation, transitions from rubbery plateau into regime. Both SAOS creep data visually superposed master curves horizontal shift factors exhibit Arrhenius behavior. However, application these determined to fails align single curve. (aSAOS) collapse short-time data, their activation energy (EaSAOS) matches effective Williams–Landel–Ferry homopolymer, indicating dynamics correspond strand segment relaxations. Creep (acreep) long-time (Eacreep) significantly larger than energies predicted by established theoretical models transient networks. We speculate discrepancy between experiment theory due dependence cross-linker mobility within matrix, which not fully captured models.

Язык: Английский

Процитировано

22
Phosphonate‐influenced Diels‐Alder chemistry toward multi‐path recyclable, fire safe thermoset and its carbon fiber composites DOI Creative Commons

Song Gu,

Shao‐Dong Xu,

Jiahui Lü

и другие.

EcoMat, Год журнала: 2023, Номер 5(9)

Опубликована: Июнь 28, 2023

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

Язык: Английский

Процитировано

21
Robust Biobased Vitrimers and Its Application to Closed-Loop Recyclable Carbon Fiber-Reinforced Composites DOI

Jiyae Hong,

Younggi Hong, Jisu Jeong

и другие.

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(38), С. 14112 - 14123

Опубликована: Сен. 5, 2023

Vitrimers are being actively studied as sustainable plastics. To that end, robust vitrimer films fabricated from a ternary aqueous solution of tannic acid (TA), boric (BA), and polyvinyl alcohol (PVA) reported herein. The trimeric include B–O–C dynamic covalent bonds. optimal film exhibits excellent crosslinking density (0.0471 mol/cm3), tensile strength (77 MPa), modulus (3.2 GPa). A carbon–fiber-reinforced (CFRV) was prepared with carbon fiber at temperatures above Tv. CFRV (tensile strength, 570 MPa; modulus, 21 GPa) can be used structural composite material. Additionally, it retains the unique recyclability reprocessability vitrimer. solution-cast reproduced during recycling, similar to original recreated by remolding recovered film. synthesized biobased high-strength facilitate development carbon–fiber-composite materials.

Язык: Английский

Процитировано

21