Four-fold increase in epoxide polymerization rate with change of alkyl-substitution on mono-μ-oxo-dialuminum initiators

Ferrier, Robert C.; Imbrogno, Jennifer; Rodriguez, Christina G.; Chwatko, Malgorzata; Meyer, Paul W.; Lynd, Nathaniel A.

doi:10.1039/c7py00894e

Cited by 20 publications

(63 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently developed mono(μ-alkoxo)bis(alkylaluminum) (MOB) compounds are tolerant to monomer functional group while still providing molecular weight control for epoxide polymerizations without any chain transfer reactions present. , Additionally, the MOB compounds are trivial to synthesize and use for epoxide polymerizations and therefore provide access for nonexperts to polyethers with tunable molecular weight, composition, and architecture. ,, The MOB compounds can be split into two separate components that facilitate epoxide polymerization; one consisting of a polymerization catalyst portion (e.g., Et 3 NAlMe 3 ) and one consisting of a bis((μ-alkoxo)-dialkylaluminum) (BOD) initiator portion (e.g., [Et 2 Al(μ-OCH 2 CH 2 OMe)] 2 ) . The result of this split was that the polymer end group could be controlled using different initiator chemistries with a limited effect on polymerization kinetics.…”

Section: Introductionmentioning

confidence: 99%

Aluminum-Based Initiators from Thiols for Epoxide Polymerizations

Safaie

Rawal²,

Ohno

et al. 2020

Macromolecules

Self Cite

View full text Add to dashboard Cite

We present a new method for epoxide polymerizations utilizing aluminum-based initiators, which leverage the chemical versatility of thiol compounds to control the polymer end group. The homo- and co-polymerization of various epoxides, such as epichlorohydrin and propylene oxide, demonstrate the flexibility of the initiators. Polymer molecular weight was controlled up to 100 kg/mol for the epoxides studied while maintaining relatively narrow dispersity (Đ < 1.4). We further characterized the kinetics of epoxide polymerizations through 1H NMR spectroscopy and studied how the initiator structure impacted the kinetics. Finally, we employed our initiators to polymerize from thiol end-functionalized poly(methyl methacrylate) (PMMA) synthesized through reversible addition fragmentation chain transfer (RAFT) polymerization, which allows us to easily create block copolymers made from vinyl and epoxide monomers. Therefore, this new synthetic tool allows for the facile polymerization of epoxides into well-defined, functional, polyether materials.

show abstract

Section: Introductionmentioning

confidence: 99%

Aluminum-Based Initiators from Thiols for Epoxide Polymerizations

Safaie

Rawal²,

Ohno

et al. 2020

Macromolecules

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recent advances in catalyst development for the synthesis of atactic polyethers with precise control of molecular weight [3] inspired us to develop ac atalyst that would give isotactic polyethers with similar control. To achieve ah igher level of isotacticity while maintaining alow dispersity,anionic polymerizations of enantiopure epoxides have been used.…”

mentioning

confidence: 99%

Bimetallic Chromium Catalysts with Chain Transfer Agents: A Route to Isotactic Poly(propylene oxide)s with Narrow Dispersities

2018

View full text Add to dashboard Cite

Bimetallic chromium catalysts are investigated for the enantioselective polymerization of propylene oxide.T he catalyst is composed of two salen chromiumspecies linked by an alkylchain, the length of which significantly impacts the rate of polymerization. While the use of achloride initiator on the catalyst resulted in bimodal molecular weight distributions, switching to at rifluoroacetate initiating group and adding ad iol chain transfer agent afforded polymers of controllable molecular weight with low, unimodal dispersities.

show abstract

“…75 Later iterations improved reaction kinetics and control. Lynd, Ferrier, and co-workers varied the alkyl substitutions on the aluminum 72 and on the amine of the alcohol ligand, 73 to investigate kinetic effects. They found kinetics were enhanced with smaller alkyls on the amine and bulkier alkyls on the aluminum.…”

Section: Coordinative Methods For Ech (Co) Polymerizationmentioning

confidence: 99%

The versatile, functional polyether, polyepichlorohydrin: History, synthesis, and applications

Shukla

Ferrier

2021

Journal of Polymer Science

Self Cite

View full text Add to dashboard Cite

Polyepichlorohydrin (PECH) is a functional polyether first synthesized in the 1950's by the catalytic ring opening polymerization of epichlorohydrin (ECH), its inexpensive epoxide pre-cursor. PECH elastomers are used in diverse commercial applications due to their unique combination of properties including low temperature flexibility and heat and oil resistance. PECH holds an interesting place in polymer history as its synthesis led to the discovery of highly effective aluminum-based catalysts for epoxide polymerizations and a new class of high molecular weight polyether elastomers by an exceptional polymer chemist, Edwin J. Vandenberg. ECH is an ideal feedstock for polymer materials as it is functional, inexpensive, and produced through environmentally friendly means. However, due to the alkyl chloride pendant, polymerizations involving ECH are difficult and limited synthetic advancement has occurred until very recently. This focused review will discuss modern polymerization methods involving ECH while giving a historical perspective on the evolution of these techniques. We will also review applications of ECH-based polymers and discuss the future development of these materials. We hope to convince the reader to explore ECH-based materials in their own work.

show abstract

Four-fold increase in epoxide polymerization rate with change of alkyl-substitution on mono-μ-oxo-dialuminum initiators

Abstract: We present an improvement in the rate, utility, and mechanistic understanding of mono-μ-oxo-dialuminum initiators for epoxide ring-opening polymerization.

Cited by 20 publications

References 27 publications

Aluminum-Based Initiators from Thiols for Epoxide Polymerizations

Aluminum-Based Initiators from Thiols for Epoxide Polymerizations

Bimetallic Chromium Catalysts with Chain Transfer Agents: A Route to Isotactic Poly(propylene oxide)s with Narrow Dispersities

The versatile, functional polyether, polyepichlorohydrin: History, synthesis, and applications

Contact Info

Product

Resources

About