Surface activated zinc-glutarate for the copolymerization of CO₂ and epoxides

Abstract

Zinc-glutarate (ZnGA) is a promising catalyst that can form polymers from CO2 and epoxides, thereby contributing to the development of CO2 utilization technologies and future sustainability. One of the obstacles...

Ultrathin Zn-Gallate Catalyst: A Remarkable Performer in CO2 and Propylene Oxide Polymerization

“… a Reaction conditions: PO (75 mmol, entries 1–5; 150 mmol, entries 6 and 7; 225 mmol, entries 8 and 9) was used. b The data was extracted from ref . c f CO 2 : {[PPC]}/{[PPC] + [PPO]} determined by 1 H NMR, selectivity: [PO incorporated into polymer]/{[propylene carbonate] + [PO incorporated into polymer]} determined by 1 H NMR. d M n and M w / M n values were determined by SEC-MALS (THF). e M n and M w / M n values were determined by SEC (THF). …”

“…Subsequently, there has been extensive research on both homogeneous and heterogeneous zinc-based catalysts to enhance catalytic activity, increase the carbonate fraction, and decrease monomer carbonate formation. − While heterogeneous catalysts offer economic advantages, the lack of understanding of their catalytic activity impeded the advancement of efficient zinc-based heterogeneous catalysts. Currently, the most potent heterogeneous catalyst reported for producing alternating polycarbonate from propylene oxide (PO) and CO 2 is zinc glutarate (ZnGA), which exhibited an activity of 0.083 kg/g-cat. ,− However, the catalytic activity of ZnGA is still low to be used in the commercial polymerization process although extensive studies have attempted to improve ZnGA’s catalytic activity. − …”

“…For comparison, the catalytic activities of ZnGA, synthesized from ZnO and glutaric acid, and Zn(OAc) 2 •2H 2 O, glutaric acid, and PE6400, were reported to be 0.033 and 0.083 kg/g-cat, respectively. 21,29 To shed light on its exceptional catalytic properties, we provide a comprehensive analysis of the morphology and composition of Zn-gallate.…”

“…We employed this ultrathin catalyst for the copolymerization of CO 2 and epoxide, and it exhibits outstanding catalytic activity (3.01 kg/g-cat), a high proportion of carbonate linkages (f CO 2 = 0.97), and limited monomer formation (9%). For comparison, the catalytic activities of ZnGA, synthesized from ZnO and glutaric acid, and Zn­(OAc) 2 ·2H 2 O, glutaric acid, and PE6400, were reported to be 0.033 and 0.083 kg/g-cat, respectively. , To shed light on its exceptional catalytic properties, we provide a comprehensive analysis of the morphology and composition of Zn-gallate.…”

Preparation of Well-Defined Double-Metal Cyanide Catalysts for Propylene Oxide Polymerization and CO2 Copolymerization

“…Our team and others have attempted to synthesize DMC catalysts, albeit with constrained success, using H 3 Co(CN) 6 in a replacement of K 3 Co(CN) 6 and avoiding the need for excessive ZnCl 2 with elimination of multiple tedious filtration processes. − Although H 3 Co(CN) 6 was reported as far back as 1847, its preparative-scale synthesis was recently achieved (Scheme ). , The reaction involved treating K 3 Co(CN) 6 with 2.25 equiv of H 2 SO 4 in water, followed by filtration to remove the byproduct K 2 SO 4 .…”