Reversible electrostatically crosslinked amphiphilic conetworks from star-shaped block copolymers

作为FOR 2811研究小组的一部分，本项目旨在通过带相反电荷的星形二嵌段共聚物之间的静电相互作用来实现可逆的两亲性网络（ACN）。为此目的，使用星形4臂系统，其在每个臂（PE）上具有带电的阻流块。一方面，使用永久带电的PE，但另一方面与可变电荷的聚两性电解质组合，其取决于pH，然后与带相反电荷的PE嵌段进行吸引或排斥相互作用。星也包括一个中性亲水或疏水内部块。此外，通过合成具有2+2臂与共价偶联剂以及带电链段的组合的星星聚合物来制备混合共价/可逆ACN。也将靶向可转换的ACN，例如通过掺入具有临界溶解温度（LCST或UCST）的亲水性嵌段。与其他子项目合作，在FOR 2811中，我们还希望解决取决于外部条件的ACN的形成，可逆性和稳定性的相关性。此外，我们希望发展的结构和稳定性的ACN以及它们的溶胀和/或渗透性的合适的探针分子的外部条件以及溶剂质量的变化下的理解。最后但并非最不重要的，这样的ACN释放效应分子和应用程序作为智能基板细胞生长的适用性将进行调查。

The present project as part of the research group FOR 2811 aims at reversible amphiphilic conetworks (ACN) by electrostatic interaction between oppositely charged star-shaped diblock copolymers. For this purpose, star-shaped 4-arm systems are used, which have a charged polyelectrolyte block on each arm (PE). On the one hand, permanently charged PE are used, but on the other hand combined with polyampholytes of variable charge, which, depending on the pH, then enter into attractive or repulsive interactions with an oppositely charged PE block. The stars also consist of either a neutral hydrophilic or hydrophobic inner block. Furthermore, mixed covalent/reversible ACNs are prepared by synthesizing star polymers with a 2+2 combination of arms with a covalent coupling agent as well as charged segments. Switchable ACNs will also be targeted, for example by incorporating hydrophilic blocks with a critical solution temperature (LCST or UCST). In collaboration with other subprojects, within FOR 2811 we also want to address a correlation of formation, reversibility and stability of ACN depending on external conditions. In addition, we want to develop an understanding of the structure and stability of ACN as well as their swelling and/or penetrability by suitable probe molecules under variation of external conditions as well as solvent quality. Last but not least, the suitability of such ACN for releasing effector molecules and for application as smart substrates for cell growth will be investigated.