Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States.
J Am Chem Soc. 2010 Dec 1;132(47):16741-4. doi: 10.1021/ja1078305. Epub 2010 Nov 4.
A novel giant surfactant possessing a well-defined hydrophilic head and a hydrophobic polymeric tail, polystyrene-(carboxylic acid-functionalized polyhedral oligomeric silsesquioxane) conjugate (PS-APOSS), has been designed and synthesized via living anionic polymerization, hydrosilylation, and thiol-ene "click" chemistry. PS-APOSS forms micelles in selective solvents, and the micellar morphology can be tuned from vesicles to wormlike cylinders and further to spheres by increasing the degree of ionization of the carboxylic acid. The effect of APOSS-APOSS interactions was proven to be essential in the morphological transformation of the micelles. The PS tails in these micellar cores were found to be highly stretched in comparison with those in traditional amphiphilic block copolymers, and this can be explained in terms of minimization of free energy. This novel class of giant surfactants expands the scope of macromolecular amphiphiles and provides a platform for the study of the basic physical principles of their self-assembly behavior.
一种新型的巨型表面活性剂，具有明确的亲水头部和疏水聚合物尾部，聚苯乙烯-（羧酸官能化多面体低聚倍半硅氧烷）接枝物（PS-APOSS），通过活性阴离子聚合、硅氢化和硫醇-烯“点击”化学设计和合成。PS-APOSS 在选择性溶剂中形成胶束，通过增加羧酸的离解度，可以将胶束形态从囊泡调至蠕虫状圆柱和进一步调至球体。证明了 APOSS-APOSS 相互作用对胶束形态转变至关重要。与传统的两亲性嵌段共聚物相比，这些胶束核中的 PS 尾链被发现高度伸展，这可以用自由能最小化来解释。这种新型的巨型表面活性剂扩大了高分子两亲物的范围，并为研究其自组装行为的基本物理原理提供了一个平台。
