Polymerization induced hierarchical self-assembly (PIHSA), combining liquid crystallization and polymerization induced self-assembly, is a facile approach to synthesize block copolymer (BCP) nanoparticles (NPs) with non-spherical morphologies. Herein, a PIHSA formulation based on azobenzene-containing poly(N,N-dimethylaminoethyl methacrylate)-b-poly (11-(4-(4-butylphenylazo) phenoxy) undecyl methacrylate) (PDMAEMA-b-PMAAz) BCPs was developed by reversible addition–fragmentation chain-transfer dispersion polymerization in n-butanol at 10% w/w solid content. According to the dispersion polymerization kinetics, a relatively high monomer conversion of ∼95% was achieved within 11.5 h. The morphology evolution was investigated in detail by tuning the chain length of PDMAEMA and feed ratio of MAAz/PDMAEMA. A morphology phase diagram was constructed. Non-spherical morphologies, especially one-dimensional morphologies, occupied a remarkable phase region due to the liquid crystallization of the azobenzene-containing core-forming block. Taking advantage of the photo-isomerization properties of azobenzene moieties, the NPs underwent morphological transformation upon alternate UV/Vis irradiation. This work expands the PIHSA systems and would be helpful for potential applications, such as coating, smart devices, and gene delivery materials.

中文翻译：

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聚合诱导的分级自组装合成含偶氮苯的液晶嵌段共聚物纳米粒子

聚合诱导分级自组装（PIHSA），结合了液晶和聚合诱导自组装，是一种合成具有非球形形态的嵌段共聚物（BCP）纳米粒子（NP）的简便方法。在此，通过以下方法开发了基于含偶氮苯的聚（N，N-甲基丙烯酸二甲基氨基乙基酯）-b-聚（甲基丙烯酸11-（4-（4-丁基苯基偶氮）苯氧基）十一烷基酯）（PDMAEMA- b -PMAAz）BCP的PIHSA配方在可逆加成-断裂链转移分散聚合ñ-固含量为10％w / w的丁醇。根据分散聚合动力学，在11.5小时内可达到约95％的较高单体转化率。通过调节PDMAEMA的链长和MAAz / PDMAEMA的进料比，详细研究了形态演变。构造了形态相图。非球形形态，特别是一维形态，由于含偶氮苯的成核嵌段的液晶而占据了显着的相区域。利用偶氮苯部分的光致异构化特性，在交替的UV / Vis照射下，NPs经历了形态转变。这项工作扩展了PIHSA系统，将有助于潜在的应用，例如涂层，智能设备和基因传递材料。