Tunable, Quantitative Fenton‐RAFT Polymerization via Metered Reagent Addition,Macromolecular Rapid Communications

当前位置： X-MOL 学术 › Macromol. Rapid Commun. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Tunable, Quantitative Fenton‐RAFT Polymerization via Metered Reagent Addition
Macromolecular Rapid Communications ( IF 4.2 ) Pub Date : 2018-05-10 , DOI: 10.1002/marc.201800179
Mitchell D. Nothling ₁ , Thomas G. McKenzie ₁ , Amin Reyhani ₁ , Greg G. Qiao ₁

Affiliation

A continuous supply of radical species is a key requirement for activating chain growth and accessing quantitative monomer conversions in reversible addition‐fragmentation chain transfer (RAFT) polymerization. In Fenton‐RAFT, activation is provided by hydroxyl radicals, whose indiscriminate reactivity and short‐lived nature poses a challenge to accessing extended polymerization times and quantitative monomer conversions. Here, an alternative Fenton‐RAFT procedure is presented, whereby radical generation can be finely controlled via metered dosing of a component of the Fenton redox reaction (H₂O₂) using an external pumping system. By limiting the instantaneous flux of radicals and ensuring sustained radical generation over tunable time periods, metered reagent addition reduces unwanted radical “wasting” reactions and provides access to consistent quantitative monomer conversions with high chain‐end fidelity. Fine tuning of radical concentration during polymerization is achieved simply via adjustment of reagent dose rate, offering significant potential for automation. This modular strategy holds promise for extending traditional RAFT initiation toward more tightly regulated radical concentration profiles and affords excellent prospects for the automation of Fenton‐RAFT polymerization.

中文翻译：

通过计量加入试剂进行可调谐，定量的Fenton-RAFT聚合

连续供应自由基是激活可逆加成-断裂链转移（RAFT）聚合反应中链增长和获得定量单体转化的关键要求。在Fenton-RAFT中，活化是由羟基自由基提供的，该羟基自由基具有不加区别的反应性和短寿命，这对延长聚合时间和定量单体转化提出了挑战。在这里，提出了一种替代性的Fenton-RAFT程序，由此可以通过计量加入Fenton氧化还原反应（H ₂ O _2）的组分来精确控制自由基的产生。）使用外部泵送系统。通过限制自由基的瞬时通量并确保在可调的时间内持续产生自由基，计量加入的试剂可减少不需要的自由基“浪费”反应，并以高链端保真度提供一致的定量单体转化率。只需调整试剂剂量率即可实现聚合过程中自由基浓度的精细调节，为自动化提供了巨大潜力。这种模块化策略有望将传统的RAFT引发扩展到更严格调节的自由基浓度曲线，并为Fenton-RAFT聚合的自动化提供了极好的前景。

更新日期：2018-05-10

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11