摘要
分子刷聚合物伸展的高分子主链、高密度的侧链和较低的侧链空间缠结,使其展现出独特的流变学、力学性能和特殊的分子聚集状态,在纳米技术、表面科学等领域有着广泛的应用前景.基于同时含有2-羰基溴与炔基基团的大分子试剂聚2-((2-溴代丙酰氧基)甲基)丙烯酸丙炔酯,引发偶氮苯丙烯酸酯单体的原子转移自由基聚合(ATRP)与叠氮功能化的巴比妥酸衍生物的点击反应,合成了新型含偶氮苯侧链的分子刷聚合物聚丙烯酸酯-g-聚(6-(4-丁基-4′-氧偶氮苯)正己基丙烯酸酯)/巴比妥酸(PA-g-PAzo/Bar),研究了其在溶液中的自组装和光响应性行为.随着分子刷聚合物浓度的增加,聚集体由柱状胶束向复合胶束转变.由于光响应性偶氮苯侧链的存在,在紫外光的照射下偶氮苯生色团发生trans-cis异构化转变,促使柱状胶束融合形成多孔网状聚集体,同时球形复合胶束融合形成珍珠项链状聚集体.
Molecular brushes(MBs)are a unique type of branched macromolecules which graft polymeric chains onto a linear polymeric backbone densely.Crowded tethered side chains generate strong steric repulsion and force the backbone to stretch out,resulting in a persistent cylindrical shape and low density of entanglements of brushes.Owing to the unique rheological and mechanical properties and self-assembly behaviors,MBs show a great potential in nanotechnology and surface science.Herein,the synthesis of novel MBs of polyacrylate-g-poly(6-(4-butyl-4'-oxyazobenzene)hexylacrylate)/barbituric acid(PA-g-PAzo/Bar)was reported,in which PAzo brushes and hydrogen-bonding barbituric acid were grafted using the combination of concurrent atom transfer radical polymerization(ATRP)and click reaction.MBs-based aggregates change from cylinder to compound micelle by increasing the concentration.It is interesting that morphology transitions of cylinder-to-porous nanosheet and compound micelle-to-pearl-necklace were observed upon UV irradiation,that was ascribed to the trans-to-cis isomerization of PAzo brushes.
作者
钱鸿宇
何品
张璐
陈珂
徐彬彬
林绍梁
Qian Hongyu;He Pin;Zhang Lu;Chen Ke;Xu Binbin;Lin Shaoliang(School of Materials Science and Engineering,East China University of Science and Technology,Shanghai 200237)
出处
《有机化学》
SCIE
CAS
CSCD
北大核心
2021年第7期2891-2897,共7页
Chinese Journal of Organic Chemistry
基金
国家自然科学基金(Nos.52073092,51873061,22001072)资助项目.
关键词
偶氮苯
分子刷聚合物
光响应性
超分子自组装
azobenzene
molecular brushes
photo-responsiveness
supramolecular self-assembly
