Univ Rennes, CNRS, ISCR-UMR 6226, 35000, Rennes, France.
Chem Asian J. 2022 Sep 1;17(17):e202200641. doi: 10.1002/asia.202200641. Epub 2022 Jul 27.
Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible polyesters with a wide range of applications; in particular, they currently stand as promising alternatives to conventional polyolefin-based "plastics". The introduction of sulfur atoms within the PHAs backbone can endow the resulting polythioesters (PTEs) with differentiated, sometimes enhanced thermal, optical and mechanical properties, thereby widening their versatility and use. Hence, PTEs have been gaining increasing attention over the past half-decade. This review highlights recent advances towards the synthesis of well-defined PTEs by ring-opening polymerization (ROP) of cyclic thioesters - namely thiolactones - as well as of S-carboxyanhydrides and thionolactones; it also covers the ring-opening copolymerization (ROCOP) of cyclic thioanhydrides or thiolactones with epoxides or episulfides. Most of the ROP reactions described are of anionic type, mediated by inorganic, organic or organometallic initiators/catalysts, along with a few enzymatic reactions as well. Emphasis is placed on the reactivity of the thio monomers, in relation to their ring-size ranging from 4- to 5-, 6- and 7-membered cycles, the nature of the catalyst/initiating systems implemented and their efficiency in terms of activity and control over the PTE molar mass, dispersity, topology, and microstructure.
聚羟基烷酸酯（PHAs）是一种可生物降解和生物相容的聚酯，具有广泛的应用；特别是，它们目前是传统聚烯烃基“塑料”的有前途的替代品。在 PHAs 主链中引入硫原子可以赋予所得的聚硫酯（PTE）不同的、有时增强的热、光和机械性能，从而拓宽其多功能性和用途。因此，在过去的五年中，PTE 引起了越来越多的关注。本文综述了近年来通过环状硫酯（即硫内酯）的开环聚合（ROP）、S-羧酸盐和硫内酯的合成、环状硫代酸酐或硫内酯与环氧化物或环硫醚的开环共聚（ROCOP）合成结构明确的 PTE 的最新进展；还介绍了环状硫代酸酐或硫内酯与环氧化物或环硫醚的开环共聚（ROCOP）。所描述的大多数 ROP 反应都是阴离子型的，由无机、有机或有机金属引发剂/催化剂介导，还有一些酶反应。重点介绍了硫单体的反应性，与其环大小有关，范围从 4-到 5-、6-和 7 元环，所采用的催化剂/引发体系的性质，以及它们在活性和控制 PTE 摩尔质量、分散度、拓扑结构和微观结构方面的效率。
