Taking Plastics with a Pinch of Salt Polyester-Based Polyelectrolyte Complexes: from Synthesis to Decomplexation

The main aspect of this work revolves around the synthesis of polyester-based polyelectrolytes. Melt polycondensation and ring-opening polymerization strategies were employed, making predominant use of biobased monomers. First, we demonstrate a synthetic route toward polyester-based PECs via melt polycondensation. The resulting PEC exhibits reduced brittleness compared to state-of-the-art vinyl-based PECs. Furthermore, the lower charge density along the polymer backbone enables processing at reduced temperatures and without the need for plasticizers. When exposed to a seawater mimic, the polyester-based PEC dissolves within 30 minutes. 
Subsequently, we explore ring-opening polymerization of lactones as an alternative route towards polyester-based polyelectrolytes, allowing improved control of the polydispersity. Through systematic post-modification of the ring-opened lactones, we examine the effects of charge density and hydrophobicity of the polyelectrolytes on the complexation behavior, and the resulting thermomechanical properties are highlighted. The findings of this thesis advance the understanding of polyester polyelectrolyte synthesis and elucidate the influence of charge density and hydrophobicity on material properties.