Optimisation of Synthesis and Processing Conditions of a Recyclable Cross-Linked Polyimine-Based Material for Electrical Engineering

Polymeric materials are essential in electrical engineering and their recyclability is very important. While thermoplastics without cross-linking can be easily recycled, the same cannot be said for cross-linked ones, which are much more difficult to recycle. However, polyimine-based polymers offer a promising recycling solution due to their reversible covalent network. Polyimine-based polymers are well recyclable but have limitations in some electrical applications due to their wettability. This study investigates how the synthesis conditions affect the properties of a particular polyimine-based material and looks at the effect of different solvent and reactant ratios on the dilution and viscosity of the prepared material. Cryogenic milling and processing techniques were used to simulate the recycling process. The research used these methods to evaluate the response of the material to recycling-like conditions. The study also aimed to determine the most suitable parameters, such as temperature, pressure and exposure time, for the repeated production of bulk samples of polyimine-based polymers. In the first phase, the mass loss was analysed by mass analysis, in which the research deals with solvent evaporation, and the chemical structure (occurrence of hydroxy groups -OH) by Fourier transform infrared spectroscopy in order to evaluate the effect of synthesis and processing conditions on the material properties. The aim of the research was to provide insights into how the properties of polyimine-based polymers can be tailored by controlled synthesis and processing conditions, thus increasing their suitability for different electrical applications.