Ring‐Opening Polymerization Strategies for Degradable Polyesters

Homoleptic phenoxy-imine pyridine zinc complexes: efficient catalysts for solvent free synthesis and chemical degradation of polyesters

“…Regarding PLA production, it is obtained industrially by ring-opening polymerization (ROP) of lactide, promoted by tin catalysts that are highly toxic. 18 Thus, the development of efficient, easily synthesized, low-cost and highly robust catalytic systems is of crucial importance. 19–22 In this context, zinc 23 and magnesium 24–26 complexes represent potent catalysts to promote the ring-opening polymerization of lactide with high efficiency and excellent control.…”

Brønsted acid catalysis opens a new route to polythiolesters via the direct condensation of thiolactic acid to thiolactide

“…Secondly, attempts were made to polymerize TLD in the presence of strong organic acids known to catalyze cationic ROP of lactones, such as diphenyl phosphate (DPP, p K a = 2.04), p -TSA (p K a = −2.8) and trifluoromethanesulphonic acid (TfOH, p K a = −14.7). 33 None of the acids induced polymerization in the presence or absence of BnOH at room temperature during 48 h of reaction (Table 3, entries 4–9). However, some minor degradation of TLD to its linear dimer was observed.…”

“…For an overview of all commonly used ROP catalyst types and their mechanisms in lactone context, see our recent review. 33 Monomer conversion (mol%) was determined via 1 H-NMR (400 MHz, CDCl 3 ) (see Fig. S24†) and the MW and polydispersity ( D ) of the materials were obtained by gel permeation chromatography (GPC).…”

Sustainable Polythioesters via Thio(no)lactones: Monomer Synthesis, Ring‐Opening Polymerization, End‐of‐Life Considerations, and Industrial Perspectives

“…[1,2] In this context, aliphatic polyesters (PEs), such as poly(lactic acid) (PLA), polybutylene adipate terephthalate (PBAT), and polyhydroxyalkanoate (PHA), have become increasingly popular as (potential) alternatives for conventional plastics, thanks to their biobased and/or biodegradable and often biocompatible character combined with sufficient thermal and mechanical properties as well as industrially viable production processes. Industrial PEs are made by polycondensation of dialcohols with dicarboxylic acids (PBAT), [3] by ring-opening polymerization (ROP) of (di)lactones (PLA), [4] or through microbial synthesis (PHA). [5] Polythioesters (PTEs), the sulfur-containing analogs of PEs, have attracted far less attention and currently no PTEs have been commercialized.…”

“…Ring-opening polymerization, being a chain-growth polymerization reaction in which a cyclic monomer is added to a growing polymer chain by ring-opening the monomer, often enables the controlled generation of high MM polymers with low Đ under mild reaction conditions and is therefore of great interest. [4,39] Although the literature on PTE synthesis via ROP is relatively limited, attempts have been described starting from thio(no)lactones (Scheme 3A) and S-carboxyanhydrides (Scheme 3B). [40] More recently, also the ring-opening alternating An Sofie Narmon obtained her M.Sc.…”