Upcycling/recycling of waste polymers to reduce the exponentially increasing plastic pollution is an environmental subject of great importance. Accordingly, in this work, we propose the use of an “all-in-one” photolytic hydrogen atom transfer (photo-HAT) reagent (phenacyl bromide) that can in situ generate bromine radicals, acetophenone, HBr, and H₂O₂, resulting in a total of four well-established, potent intermediates for the photodegradation/photodepolymerization of waste polystyrene (PS) foam. Under ambient conditions, using ethyl acetate solvent and the stated photo-HAT catalyst, waste PS (M_n > 120 kg/mol) breaks down to oligomers with less than eight styrene units (M_n < 0.76 kg/mol) and to several organic compounds, such as aromatic ketones, oxygenated alkenes in conjunction with acetophenone and trace benzoic acid. A plausible reaction mechanism demonstrating the role of each in situ generated intermediate involved in this photodegradation is proposed. Herein, we present an efficient metal-free photo-oxidative degradation method for commercial PS using a cheap organic reagent at ambient sustainable conditions. Ultimately, this study provides a promising alternative to recent waste polymer valorization methods involving toxic transition metal salts and halogenated solvents.

中文翻译：

---

在环境条件下使用“一体式”Photo-HAT 试剂对废弃聚苯乙烯泡沫进行高效光解分解


对废弃聚合物进行升级回收/回收以减少呈指数级增长的塑料污染是一个非常重要的环境问题。因此，在这项工作中，我们建议使用一种“一体化”光解氢原子转移（photo-HAT）试剂（苯甲酰溴），它可以原位产生溴自由基、苯乙酮、HBr和H ₂ O ₂ ，总共产生了四种行之有效的有效中间体，用于废旧聚苯乙烯（PS）泡沫的光降解/光解聚。在环境条件下，使用乙酸乙酯溶剂和所述photo-HAT催化剂，废PS（M _n > 120 kg/mol）分解成苯乙烯单元少于8个的低聚物（M _n