Department of Chemistry, Technische Universität Berlin, Straße des 17. Juni 124, TC-8, 10623 Berlin, Germany.
Department of Physics, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany.
J Colloid Interface Sci. 2018 Mar 1;513:638-646. doi: 10.1016/j.jcis.2017.11.071. Epub 2017 Nov 29.
Colloidal particles have been used to covalently bind ligands for the heterogenization of homogeneous catalysts. The replacement of the covalent bonds by electrostatic interactions between particles and the catalyst could preserve the selectivity of a truly homogeneous catalytic process.
Functionalized polymer particles with trimethylammonium moieties, dispersed in water, with a hydrophobic core and a hydrophilic shell have been synthesized by emulsion polymerization and have been thoroughly characterized. The ability of the particles with different monomer compositions to act as catalyst carriers has been studied. Finally, the colloidal dispersions have been applied as phase transfer agents in the multiphasic rhodium-catalyzed hydroformylation of 1-octene.
The hydrodynamic radius of the particles has been shown to be around 100 nm, and a core-shell structure could be observed by atomic force microscopy. The polymer particles were proven to act as carriers for the water-soluble hydroformylation catalyst, due to electrostatic interaction between the functionalized particles bearing ammonium groups and the sulfonated ligands of the catalyst. The particles were stable under the hydroformylation conditions and the aqueous catalyst phase could be recycled three times.
胶体颗粒已被用于通过共价键将配体键合到均相催化剂的异质化上。通过颗粒与催化剂之间的静电相互作用取代共价键，可以保持真正均相催化过程的选择性。
通过乳液聚合合成了带有三甲铵基团的功能化聚合物颗粒，分散在水中，具有疏水核和亲水壳。已经对具有不同单体组成的颗粒作为催化剂载体的能力进行了研究。最后，胶体分散体已被用作多相铑催化 1-辛烯氢甲酰化反应中的相转移剂。
颗粒的水动力半径约为 100nm，原子力显微镜观察到核壳结构。由于带铵基团的功能化颗粒与催化剂的磺化配体之间的静电相互作用，聚合物颗粒被证明可以作为水溶性氢甲酰化催化剂的载体。在氢甲酰化条件下，颗粒稳定，水相催化剂可回收 3 次。
