Defence Paul van den Tempel: "Ink jetting of Thermo-Reversible Diels-Alder Networks"

Promotors: Prof. Francesco Picchioni and Prof. Ranjita Bose

Abstract:
The aspect of recycling a product at the end of its lifetime becomes ever more important in our sustainability driven society. The same holds true for printer inks. When either being used for 3D printing or 2D printing, it is desired to reshape the prints at the end-of-life. In this dissertation, the possibility is explored to produce recyclable thermosets for 3D printing applications, by replacing the conventional irreversible crosslinks by thermally reversible ones, which can be broken by only moderate heating. The popular Diels-Alder ‘click’ reaction between furan and maleimide monomers sets the basis for the design of these thermally reversible networks. In particular, the use of smaller multifunctional furan and maleimide which were used throughout this work shows that we can find a balance between a low viscosity during printing, a strong network once being printed, and recycling temperature at the end-of-life. Part of this thesis is dedicated to the use of post-curing steps as well, making sure that a broad range of mechanical properties of the produced structure could be achieved, allowing us to print elastomeric materials, but also objects with stiffer behavior.

Dissertation