Reversible electrostatically crosslinked amphiphilic conetworks from star-shaped block copolymers

作为研究小组FOR 2811的一部分，目前的项目旨在通过反向带电的星形二嵌段共聚物之间的静电相互作用研究可逆两亲网络（ACN）。为此，使用了星形的四臂系统，每个臂上都有一个带电的聚电解质块（PE）。一方面，使用永久带电的PE，但另一方面，与可变电荷的多两性聚合物结合，根据pH值，然后与带相反电荷的PE块进行吸引或排斥相互作用。这些恒星也由中性亲水性或疏水性内部块组成。此外，通过与共价偶联剂的2+2臂组合以及带电段合成星形聚合物，制备了混合共价/可逆acn。可切换acn也将成为目标，例如，通过结合具有临界溶液温度（LCST或UCST）的亲水性块。在与其他子项目的合作中，在FOR 2811中，我们还希望根据外部条件解决ACN的形成、可逆性和稳定性之间的相关性。此外，我们希望通过合适的探针分子来了解ACN的结构和稳定性，以及它们在外部条件和溶剂质量变化下的膨胀和/或穿透性。最后但并非最不重要的是，将研究这种ACN释放效应分子的适用性以及作为细胞生长的智能底物的应用。

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.