Université de Lyon, Univ Lyon 1, CPE Lyon, CNRS, UMR 5265, C2P2 (Chemistry, Catalysis, Polymers & Processes), Team LCPP Bat 308F, 43 Bd du 11 Novembre 1918, 69616 Villeurbanne (France).
Angew Chem Int Ed Engl. 2014 Jun 23;53(26):6683-6. doi: 10.1002/anie.201403491. Epub 2014 May 22.
The present paper reports the first example of a controlled radical polymerization of ethylene using reversible addition-fragmentation chain transfer (RAFT) in the presence of xanthates (Alkyl-OC(=S)S-R) as controlling agents under relative mild conditions (70 °C, <200 bars). The specific reactivity of the produced alkyl-type propagating radicals induces a side fragmentation reaction of the stabilizing O-alkyl Z group of the controlling agents. This fragmentation, rarely observed in RAFT, was proven by NMR analyses. In addition, semicrystalline copolymers of ethylene and vinyl acetate were also prepared with a similar level of control.
本文报道了首例在相对温和的条件（70°C，<200 巴）下，使用黄原酸盐（烷基-O=C(S)S-R）作为控制剂，通过可逆加成-断裂链转移（RAFT）聚合乙烯的可控自由基聚合的例子。所生成的烷基型自由基的特殊反应性诱导了控制剂的稳定 O-烷基 Z 基团的侧链断裂反应。这种在 RAFT 中很少观察到的断裂反应，通过 NMR 分析得到了证实。此外，还通过类似的控制方法制备了乙烯和醋酸乙烯酯的半结晶共聚物。
