Chemical and Physical Debonding-on-Demand of Poly(urethane urea) Thermoset Adhesives to Facilitate the Recycling of Engineered Wooden Products

ACS Applied Polymer Materials, Год журнала: 2024, Номер 6(10), С. 5778 - 5787

Опубликована: Май 4, 2024

The demand for debondable adhesives is becoming more urgent, as countries begin implementing policies to enforce circularity and recyclability. Specifically in the construction industry, switch from carbon pool-depleting materials pool-replenishing demonstrates importance of high-demand wood species used produce engineered products. To this end, a dual chemical physical debonding adhesive was prepared with intent debond solid specimens. one-pot synthesis poly(urethane urea) (PUU) thermoresponsive furan maleimide (FM) Diels–Alder adduct capable dissociating at temperatures above 90 °C coupled thermally expanding microspheres (MS). First, PUU polymer films containing only FM bonds second control butyl spacer replacing bond were characterized. Next, simple single wooden lap specimens by using investigate bonding via shear test. Adhesives or MS tested effect versus mechanism on strength glued combination incorporated combine mechanisms, respectively, which resulted most drastic reduction tensile 71%.

Язык: Английский

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Nonisocyanate Polyurethanes Originated from Biobased Isosorbide with Good Combined Properties

ACS Applied Polymer Materials, Год журнала: 2024, Номер 6(14), С. 8133 - 8141

Опубликована: Июль 17, 2024

Polyurethane (PU) is conventionally synthesized via the isocyanate route, which has been widely reported to be hazardous environment and humans. Consequently, there an urgent need develop environmentally friendly method for preparation of nonisocyanate polyurethanes (NIPUs). Herein, a green synthetic route polyurethane, originating from dimethyl carbonate, 1,6-hexanediamine, 1,6-hexanediol, rigid biobased isosorbide introduced enhance mechanical properties heat deflection temperature NIPUs. A series polycarbonate-based (ISPCUs) were by adjusting content in hard segments. The results show that ring structure enhances thermal PU. Notably, melting point ISPCUs increased 93 119 °C, enhanced 85 °C 41 NIPUs without isosorbide. improved substantially, especially tensile strength, evidently 18 MPa PU 65 ISPCUs. This work provides synthesize with exceptional resistance properties.

Язык: Английский

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NIR photoresponsive shape memory polyurethanes composite with self-healing and anti-corrosion properties

Polymer, Год журнала: 2024, Номер 299, С. 126957 - 126957

Опубликована: Март 22, 2024

Язык: Английский

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Chemical Recycling of Step-Growth Polymers Guided by Le Chatelier’s Principle

ACS Engineering Au, Год журнала: 2024, Номер 4(5), С. 432 - 449

Опубликована: Июль 15, 2024

Although step-growth polymers (SGPs) play a fundamental role in the plastics economy, contributing significantly to various facets of our daily life, their end-of-life management remains inadequately addressed. Chemical recycling SGP wastes, involving depolymerization followed by repolymerization, emerges as promising solution toward achieving circular economy. The SGPs is usually dynamic equilibrium with polymerization reactions, thus falling under system amenable Le Chatelier's principle. This perspective endeavors elucidate interplay between principle and chemical particular emphasis on guidance provided latter process. To this end, we have selected five conventional SGPs, namely, poly(ethylene terephthalate), polyamides, polycarbonates, polyurethanes, polyureas, representatives how alterations temperature, pressure, concentrations products or reactants, catalysts influence process SGPs. Additionally, proposes several potential strategies for applying

Язык: Английский

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Biobased and aromatic Covalent Adaptable Networks: When architectures meet properties, within the framework of a circular bioeconomy

Materials Science and Engineering R Reports, Год журнала: 2024, Номер 161, С. 100882 - 100882

Опубликована: Ноя. 9, 2024

Язык: Английский

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