Catalytic Hydrogenation of Polyurethanes to Base Chemicals: From Model Systems to Commercial and End-of-Life Polyurethane Materials

JACS Au, Год журнала: 2021, Номер 1(4), С. 517 - 524

Опубликована: Апрель 6, 2021

Polyurethane (PU) is a highly valued polymer prepared from diisocyanates and polyols, it used in everyday products, such as shoe soles, mattresses, insulation materials, but also for the construction of sophisticated parts medical devices, wind turbine blades, aircrafts, spacecrafts, to name few. As PU most commonly thermoset composed cross-linked structures, its recycling complicated inefficient, leading increasing waste accumulating every year. Catalytic hydrogenation represents an atom-efficient means deconstruction polyurethanes, so far identification efficient catalyst disassembly real-life end-of-life samples has not been demonstrated. In this work, we reveal that commercially available catalyst, Ir-iPrMACHO, under 30 bar H2 150–180 °C, general effective four cornerstones PU: flexible solid, foamed, rigid isolation aromatic amines polyol fraction. For first time, variety commercial including examples foams, inline skating wheels, deconstructed into two fractions. Most desirable, our reaction conditions include use isopropyl alcohol representative green solvent. It speculated partial glycolysis at surface particles taking place solvent temperatures presence catalytic amounts base. more solubilized fragments becomes possible. isolated anilines are precursors original isocyanate building blocks, methods their conversion well-known, work reported paper provides realistic indication potential circular plastic economy solution PU. Preliminary experiments were undertaken applying Mn-iPrMACHO foam. Although successful, forcing required than those when Ir-iPrMACHO.

Язык: Английский

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Reductive depolymerization as an efficient methodology for the conversion of plastic waste into value-added compounds

Green Chemistry, Год журнала: 2021, Номер 23(19), С. 7330 - 7360

Опубликована: Янв. 1, 2021

Reductive depolymerization allows the valorization of polyester, polycarbonate and polyamide waste in a wide variety value-added compounds with good yields

Язык: Английский

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Chemoselective Hydrogenation of Nitroarenes Using an Air-Stable Base-Metal Catalyst

Organic Letters, Год журнала: 2021, Номер 23(7), С. 2742 - 2747

Опубликована: Март 23, 2021

The reduction of nitroarenes to anilines as well azobenzenes hydrazobenzenes using a single base-metal catalyst is reported. hydrogenation reactions are performed with an air-and moisture-stable manganese and proceed under relatively mild reaction conditions. transformation tolerates broad range functional groups, affording aniline derivatives in high yields. Mechanistic studies suggest that the proceeds via bifunctional activation involving metal–ligand cooperative catalysis.

Язык: Английский

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Catalytic carbon and hydrogen cycles in plastics chemistry

Chem Catalysis, Год журнала: 2022, Номер 2(4), С. 724 - 761

Опубликована: Март 2, 2022

Язык: Английский

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Dual-ionic imidazolium salts to promote synthesis of cyclic carbonates at atmospheric pressure

Green Energy & Environment, Год журнала: 2021, Номер 7(6), С. 1327 - 1339

Опубликована: Фев. 25, 2021

Novel dual-ionic imidazolium salts are shown to display excellent catalytic activity for cycloaddition of carbon dioxide and epoxides under room temperature atmospheric pressure (0.1 MPa) without any solvent co-catalyst leading 96.1% product yield. It can be reused five times keep the yield over 90%. These intriguing results attributed a new reaction mechanism, which is supported by theoretical calculations along with measurements 13C NMR spectrum Fourier transform infrared spectroscopy (FT-IR). The traced CO2-philic group an electrophilic hydrogen atom. Our work shows that incorporation feasible pathway develop efficient ionic liquids.

Язык: Английский

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