Ring-opening polymerizations and copolymerizations of epoxides using aluminum- and boron-centered catalysts

Andrea, Kori A.; Plommer, Hart; Kerton, Francesca M.

doi:10.1016/j.eurpolymj.2019.08.029

Cited by 44 publications

(40 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Catalyst design has enabled the generation of nearly perfect polycarbonates (>99% carbonate linkages) through ROCOP, by overcoming the undesired formation of polyether linkages and cyclic carbonates 70 , 72 . Most catalyst systems reported are homometallic and often multimetallic 64 , 70 , 73 , including bis-Co(II) 74 , Co(III) 75 , 76 , Fe(III) 77 , Mg(II) 67 and Zn(II) complexes 78 – 83 . Studies have pointed towards a bimetallic mechanism, which limits the use of dimeric catalysts with high monomer loadings or at high dilutions.…”

Section: Ring-opening Polymerisationmentioning

confidence: 99%

Advances in heterometallic ring-opening (co)polymerisation catalysis

2021

View full text Add to dashboard Cite

Truly sustainable plastics require renewable feedstocks coupled with efficient production and end-of-life degradation/recycling processes. Some of the most useful degradable materials are aliphatic polyesters, polycarbonates and polyamides, which are often prepared via ring-opening (co)polymerisation (RO(CO)P) using an organometallic catalyst. While there has been extensive research into ligand development, heterometallic cooperativity offers an equally promising yet underexplored strategy to improve catalyst performance, as heterometallic catalysts often exhibit significant activity and selectivity enhancements compared to their homometallic counterparts. This review describes advances in heterometallic RO(CO)P catalyst design, highlighting the overarching structure-activity trends and reactivity patterns to inform future catalyst design.

show abstract

Section: Ring-opening Polymerisationmentioning

confidence: 99%

Advances in heterometallic ring-opening (co)polymerisation catalysis

2021

View full text Add to dashboard Cite

show abstract

“…Heterogeneous catalysts include zinc glutarate (ZnGA) or carboxylates (ZnCA), double metal cyanides (DMC), as well as rare earth metal ternary catalysts; on the other hand homogeneous catalysts are based on first row transition metals such as Cr, Co, Zn, Fe, or earth abundant metals such as Al, Mg, etc. associated with different ligands. ,− Although numerous catalysts have been developed over time, none of them was actually designed to allow the copolymerization of CO 2 indiscriminately with all epoxides available; either the metal or the ligand had to be modified specifically depending upon the epoxides chosen. Kim et al first screened the activity of heterogeneous Zn–Co(III) DMC catalyst for the copolymerization of CO 2 with epoxides carrying alkyl and alkoxymethyl substituents; they found no activity for epoxides with long substituted chain such as 1-hexene oxide (HO) and 1-octene oxide (OO).…”

Section: Introductionmentioning

confidence: 99%

All-Polycarbonate Thermoplastic Elastomers Based on Triblock Copolymers Derived from Triethylborane-Mediated Sequential Copolymerization of CO₂ with Various Epoxides

et al. 2020

View full text Add to dashboard Cite

Various oxirane monomers including alkyl ether or allyl-substituted ones such as 1-butene oxide, 1-hexene oxide, 1-octene oxide, butyl glycidyl ether, allyl glycidyl ether, and 2-ethylhexyl glycidyl ether were anionically copolymerized with CO 2 into polycarbonates using onium salts as initiator in the presence of triethylborane. All copolymerizations exhibited a “living” character, and the monomer consumption was monitored by in situ Fourier-transform infrared spectroscopy. The various polycarbonate samples obtained were characterized by 1 H NMR, GPC, and differential scanning calorimetry. In a second step, all-polycarbonate triblock copolymers demonstrating elastomeric behavior were obtained in one pot by sequential copolymerization of CO 2 with two different epoxides, using a difunctional initiator. 1-Octene oxide was first copolymerized with CO 2 to form the central soft poly(octene carbonate) block which was flanked by two external rigid poly(cyclohexene carbonate) blocks obtained through subsequent copolymerization of cyclohexene oxide with CO 2 . Upon varying the ratio of 1-octene oxide to cyclohexene oxide and their respective ratios to the initiator, three all-polycarbonate triblock samples were prepared with molar masses of about 350 kg/mol and 22, 26, and 29 mol % hard block content, respectively. The resulting triblock copolymers were analyzed using 1 H NMR, GPC, thermogravimetric analysis, differential scanning calorimetry, and atomic force microscopy. All three samples demonstrated typical elastomeric behavior characterized by a high elongation at break and ultimate tensile strength in the same range as those of other natural and synthetic rubbers, in particular those used in applications such as tissue engineering.

show abstract

“…As compared with the Co analogues, (TPP)Al III -X complexes typically show inferior selectivity and produce polymers with high polyether content in ROCOP. [54][55][56][57] Yet, Al is not likely to impede the electron and energy transfer property of porphyrin ligands like Mg because of its lack of d-electron at the metal centers, while (TPP)Co III -X complexes suffer from shortened lifetime of the triplet state and prove to be ineffective for PET-RAFT polymerization. 39,40 In ROCOP catalyzed by (TPP)Al III -X, it is well-accepted that the axial group, X, initiates the reaction and aluminum carboxylate (Al-O 2 CR) and aluminum alkoxide (Al-OR) intermediates serve as the active species.…”

Section: Resultsmentioning

confidence: 99%

Aluminum Porphyrin Complex Mediated Auto-Tandem Catalysis for One-Pot Synthesis of Block Copolymers

Zhao

Zhu

et al. 2022

CCS Chem

View full text Add to dashboard Cite

Auto-tandem catalysis that uses a single catalyst to bridge and discriminate different catalytic cycles in a one-pot process is highly desirable for obtaining a high degree of structural complexity; however, it is a great challenge to develop auto-tandem catalytic systems in polymer chemistry. Herein, we report the auto-tandem catalysis by rationally designed aluminum porphyrin complexes, wherein well-controlled photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of vinyl monomers and completely alternating ring-opening copolymerization (ROCOP) of epoxides/anhydrides can occur in a concurrent or sequential manner. With a carboxylic group incorporated trithiocarbonate compound bearing a carboxylic acid group (TTC-COOH) as the bifunctional chain transfer agent (CTA), the auto-tandem catalysis provides one-pot access to diblock copolymers with predictable molecular weights and narrow distributions. Notably, the efficient electron/energy transfer from 5,10,15,20-tetrakis(2-chlorophenyl) porphyrin aluminum(III) chloride [(TPP 2-Cl )Al III -Cl] to TTC-COOH and their axial group exchange reactions completely circumvent the formations of undesirable homopolymers.

show abstract

Ring-opening polymerizations and copolymerizations of epoxides using aluminum- and boron-centered catalysts

Cited by 44 publications

References 66 publications

Advances in heterometallic ring-opening (co)polymerisation catalysis

Advances in heterometallic ring-opening (co)polymerisation catalysis

All-Polycarbonate Thermoplastic Elastomers Based on Triblock Copolymers Derived from Triethylborane-Mediated Sequential Copolymerization of CO₂ with Various Epoxides

Aluminum Porphyrin Complex Mediated Auto-Tandem Catalysis for One-Pot Synthesis of Block Copolymers

Contact Info

Product

Resources

About

Ring-opening polymerizations and copolymerizations of epoxides using aluminum- and boron-centered catalysts

Cited by 44 publications

References 66 publications

Advances in heterometallic ring-opening (co)polymerisation catalysis

Advances in heterometallic ring-opening (co)polymerisation catalysis

All-Polycarbonate Thermoplastic Elastomers Based on Triblock Copolymers Derived from Triethylborane-Mediated Sequential Copolymerization of CO2 with Various Epoxides

Aluminum Porphyrin Complex Mediated Auto-Tandem Catalysis for One-Pot Synthesis of Block Copolymers

Contact Info

Product

Resources

About

All-Polycarbonate Thermoplastic Elastomers Based on Triblock Copolymers Derived from Triethylborane-Mediated Sequential Copolymerization of CO₂ with Various Epoxides