Multicomponent Stress‐Sensing Composites Fabricated by 3D‐Printing Methodologies

Abstract

The preparation and characterization of mechanoresponsive, 3D‐printed composites are reported using a dual‐printing setup for both, liquid dispensing and fused‐deposition‐modeling. The here reported stress‐sensing materials are based on high‐ and low molecular weight mechanophores, including poly(ε‐caprolactone)‐, polyurethane‐, and alkyl(C11)‐based latent copper(I)bis(N‐heterocyclic carbenes), which can be activated by compression to trigger a fluorogenic, copper(I)‐catalyzed azide/alkyne “click”‐reaction of an azide‐functionalized fluorescent dye inside a bulk polymeric material. Focus is placed on the printability and postprinting activity of the latent mechanophores and the fluorogenic “click”‐components. The multicomponent specimen containing both, azide and alkyne, are manufactured via a 3D‐printer to place the components separately inside the specimen into void spaces generated during the FDM‐process, which subsequently are filled with liquids using a separate liquid dispenser, located within the same 3D‐printing system. The low‐molecular weight mechanophores bearing the alkyl‐C11 chains display the best printability, yielding a mechanochemical response after the 3D‐printing process.

3D Printing of Solvent-Free Supramolecular Polymers

“…The functionality is equally distributed throughout the complete material and is introduced as a part of the polymer chain, making handling and printing much easier. Commonly in 3D printing, the increase of mechanical properties is done by manufacturing polymer–filler composites or with highly complex printing techniques ( Tekinalp et al, 2014 ; Weng et al, 2016 ; Rupp and Binder, 2020 ; Rupp and Binder, 2021 ). In the following parts, the introduction of supramolecular interaction into the 3D printing field will be explored in detail, most of them being basic scientific research.…”

Selbstheilende Polymere – auch rezyklierbar

“…niert. Das entstehende Kompositmaterial wurde für über 3D Druck nachträglich geformt und direkt zur Stressdetektion verwendet werden, wenn es mit einem Fluoreszenzfarbstoff kombiniert wird [36,37].…”

Mechano‐Optical Response of Novel Polymer Composites Based on Elastic Polyurethane Matrix Filled with Low‐Molar‐Mass Cholesteric Droplets

“…These are additives such as rotaxanes, in which, upon stretching, the macrocycle is removed from the fluorophore, affecting its optical properties, [ 15–17 ] or mechanophores activated by compression to trigger a fluorogenic reaction. [ 18 ] Changes in the emission properties can be achieved by deformation of the luminescent‐dye‐doped polymer. Reorganization of the polymer structure during deformation breaks the luminescent dye excimer‐type arrangement, leading to the variation of the monomer to excimer emission ratio.…”