Single-Chain Nanoparticle Complexation at Interfaces

目前的提案研究了分子内光交联聚合物链的界面特性，即所谓的两亲单链纳米颗粒（SCNPs）作为一种新型表面活性剂。具体来说，我们将通过利用特定嵌段共聚物段之间的界面强制络合来设计SCNPs，例如水溶性聚（二甲氨基乙基甲基丙烯酸酯）（PDMAEMA）在界面上与油溶性聚（环氧丙烷）（PPO）结合，导致形成预先排列/折叠的三明治构象，与经典的煎饼构象截然不同，两个嵌段之间的距离更大。这些预先安排好的三明治将在油/水界面通过光化学交联方法保存（单纯的嵌段间交联和统计的嵌段间和嵌段内交联；后者将允许桥接嵌段共聚物的同一嵌段的不同部分，而前者只在同一链的两个嵌段之间产生桥接）。为了实现这一目标，每个块的精心设计和交联过程至关重要。通过改变共聚物组成和交联条件，可以改变交联度，在某些情况下甚至可以逆转。随后，将在Langmuir槽中对聚合物进行系统的研究。我们期望得到的SCNPs具有前所未有的两亲性，例如，即使在较高的界面浓度下，链的取向也相当平行，从而导致界面处的janus型结构。因此，我们期望得到的SCNPs具有更高的表面活性剂效率，用于资源节约型应用，因为覆盖界面的聚合物数量减少了。

The current proposal investigates the interfacial properties of intramolecularly photo-crosslinked polymer chains, so-called amphiphilic single-chain nanoparticles (SCNPs) as a novel type of surfactant. Specifically, we will design SCNPs by exploiting interface-enforced complexation between segments of specific block copolymers, e.g. water-soluble poly(dimethylaminoethyl methacrylate) (PDMAEMA) associating at the interface with oil-soluble poly(propylene oxide) (PPO), leading to the formation of prearranged/collapsed sandwich conformations, critically different to the classical pancake conformation with a larger distance between both blocks. These prearranged sandwiches will be conserved by photochemical crosslinking methods at the oil/water interface (mere interblock crosslinking and statistical inter- and intrablock crosslinking; the latter would allow bridging different parts of the same block of the block copolymer, while the former generates bridges only between the two blocks of the same chain). To achieve this goal, the careful design of each block and the crosslinking procedure is critical. By variation of the copolymer composition and crosslinking conditions, the crosslinking degree can be altered and, in some cases, even reversed. Subsequently, the polymers will be investigated systematically at the Langmuir trough. We expect unprecedented amphiphilic properties of the resulting SCNPs, for example a rather parallel orientation of the chains even at higher interfacial concentration leading to a Janus-type structure at the interface. Hence, we expect that the resulting SCNPs feature an increased surfactant efficiency for resource-efficient applications due to decreased polymer amounts to cover the interface.