ATRP与点击化学结合制备树状星型聚合物

本文通过将ATRP技术和点击化学相结合的方法来制备树状星型聚合物[(PMMA)2PSt]4. 首先通过1,3-偶极环加成反应对ATRP的核预聚物进行端基修饰, 得到后继ATRP反应的大分子引发剂, 进而引发第二单体的ATRP聚合生成树状星型聚合物.

Synthesis of Dendrimer-like Star Polymer by the Combination of ATRP and Click Chemistry

A new approach to the synthesis of dendrimer-like star polymer, [(PMMA)2PSt]4, was presented via the combination of atom transfer radical polymerization(ATRP) and ckick chemistry. Firstly four-arm bromine-terminated polystyrene(PSt-Br)4 was obtained from ATRP of styrene using pentaerythritol tetra(2-bromoisobutyrate) as an initiator, and the (PSt-Br)4 was efficiently converted to the azido-terminated polymers[(PSt-N3)4] through the bromine substitution reaction with sodium azide. Furthermore, the(PSt-N3)4 reacted with propargyl 2,2-bis[2-(bromomethyl)propionato]propionyrate via a click reaction, 1,3-dipolar cycloaddition reaction, and the polymer[(PSt-Br2)4] containing eight end-bromine was obtained. The (PSt-Br2)4 could further serve as a macroinitiator for the ATRP of methyl methacrylate(MMA). Accordingly, the dendrimer-like star polymer, [(PMMA)2PSt]4 was successfully prepared. The structure of [(PMMA)2PSt]4 was characterized via IR, 1H NMR, GPC and DSC.