Journal ArticleDOI
Guanidine and Amidine Organocatalysts for Ring-Opening Polymerization of Cyclic Esters
Bas G. G. Lohmeijer,Russell C. Pratt,Frank A. Leibfarth,John W. Logan,David A. Long,Andrew P. Dove,Fredrik Nederberg,Jeongsoo Choi,Charles G. Wade,Robert M. Waymouth,James L. Hedrick +10 more
Reads0
Chats0
TLDR
In this article, the ring-opening polymerization (ROP) of cyclic esters such as lactide (LA), δ-valerolactone (VL), and e-caprolactone(CL) was achieved.Abstract:
1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD), N-methyl-TBD (MTBD), and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) are effective organocatalysts for the ring-opening polymerization (ROP) of cyclic esters such as lactide (LA), δ-valerolactone (VL), and e-caprolactone (CL). TBD is shown to polymerize LA, VL, and CL in a fast and controlled manner, whereas MTBD and DBU polymerized LA and addition of a thiourea cocatalyst led to the ROP of VL and CL being achieved. Each of the catalysts produced polymers displaying high end group fidelity, good correlation between theoretical and observed molecular weight, and linear relationships between conversion and molecular weight. The enhanced activity of TBD relative to MTBD and DBU is attributed to its bifunctionality, enabling the simultaneous activation of both the cyclic ester monomer and the alcohol group of the initiator/propagating species. Temperature-dependent NMR studies generated individual association constants for MTBD with benzyl alcohol and thiourea with VL. ...read more
Citations
More filters
Journal ArticleDOI
Selective O-acyl ring-opening of β-butyrolactone catalyzed by trifluoromethane sulfonic acid: application to the preparation of well-defined block copolymers
Aline Couffin,Aline Couffin,Blanca Martin-Vaca,Blanca Martin-Vaca,Didier Bourissou,Didier Bourissou,Christophe Navarro +6 more
TL;DR: A detailed study of β-butyrolactone (β-BL) ring-opening polymerization with methane and trifluoromethane sulfonic acids (MSA and HOTf) is reported in this paper.
Journal ArticleDOI
Ring‐opening polymerization of lactones using binaphthyl‐diyl hydrogen phosphate as organocatalyst and resulting monosaccharide functionalization of polylactones
Yong Miao,Yupin Phuphuak,Cyril Rousseau,Cyril Rousseau,Till Bousquet,André Mortreux,Suwabun Chirachanchai,Philippe Zinck +7 more
TL;DR: Binaphthyl-diyl hydrogen phosphate has been assessed for the first time as a catalyst for the ring-opening polymerization of e-caprolactone and δ-valerolactone.
Journal ArticleDOI
Nanoporous polysulfone membranes via a degradable block copolymer precursor for redox flow batteries
Brandon P. Gindt,Daniel G. Abebe,Zhijiang J. Tang,Melanie Lindsey,Jihua Chen,Ramez A. Elgammal,Thomas A. Zawodzinski,Thomas A. Zawodzinski,Tomoko Fujiwara +8 more
TL;DR: In this article, a post-hydrolysis of polylactide (PLA) from PLA-PSU-PLA triblock copolymer membranes was used as separator for vanadium redox flow batteries.
Journal ArticleDOI
Novel synthesis of biodegradable amphiphilic linear and star block copolymers based on poly(ε-caprolactone) and poly(ethylene glycol)
TL;DR: In this article, a ring opening poly(e-caprolactone)-block-poly(ethylene glycol) and star-shaped copolymers were synthesized by ring opening polymerization of e-caproleactone.
Journal ArticleDOI
Anionic flow polymerizations toward functional polyphosphoesters in microreactors: Polymerization and UV-modification
TL;DR: In this article, the anionic ring-opening polymerization of 2-isobutyoxy-2-oxo-1,3,2-dioxaphospholane (iBP) via the use of two organocatalytic systems allowed to polymerize to nearly quantitative monomer conversion within 10 or 3min, respectively at a reaction temperature of 40°C.
References
More filters
Journal ArticleDOI
Controlled ring-opening polymerization of lactide and glycolide.
TL;DR: This work focuses on the characterization of the phytochemical components of Lactide ROP and their role in the regulation of cell reprograming.
Journal ArticleDOI
Polymerization of Lactide with Zinc and Magnesium β-Diiminate Complexes: Stereocontrol and Mechanism
Bradley M. Chamberlain,Ming Cheng,David Roger Moore,Tina M. Ovitt,Emil B. Lobkovsky,Geoffrey W. Coates +5 more
TL;DR: The substituents on the beta-diiminate ligand exert a significant influence upon the course of the polymerizations, affecting both the degree of stereoselectivity and the rate of polymerization.
Journal ArticleDOI
A review of biodegradable polymers: uses, current developments in the synthesis and characterization of biodegradable polyesters, blends of biodegradable polymers and recent advances in biodegradation studies
TL;DR: A review of the uses of biodegradable polymers in terms of their relevance within current plastic waste management of packaging materials, biomedical applications and other uses is presented in this paper.
Journal ArticleDOI
Extension of the self-consistent spectrophotometric basicity scale in acetonitrile to a full span of 28 pKa units: unification of different basicity scales.
Ivari Kaljurand,Agnes Kütt,Lilli Sooväli,Toomas Rodima,Vahur Mäemets,and Ivo Leito,Ilmar A. Koppel +6 more
TL;DR: The earlier compiled self-consistent spectrophotometric basicity scale in acetonitrile (AN) was expanded to range from 3.8 to 32.0 pK(a) units, that is 28 orders of magnitude, and 54 new relative basicity measurements were carried out and 37 new compounds were introduced to the scale.
Journal ArticleDOI
Stereochemistry of Lactide Polymerization with Chiral Catalysts: New Opportunities for Stereocontrol Using Polymer Exchange Mechanisms
Tina M. Ovitt,Geoffrey W. Coates +1 more
TL;DR: A polymer exchange mechanism is proposed to account for the PLA microstructures resulting from rac-4, which polymerizes meso-lactide to syndiotactic poly(lactic acid) (PLA) and heterotactic and isotactic stereoblock PLA, respectively.