Influence of thiocarbonylthio- RAFT agents on the homogeneity of polymer network and mechanical properties of 3D printed polymers

RAFT agents based on thiocarbonylthio-group were used in an acrylate formulation containing a phosphine oxide as photoinitiator. After optimization of the RAFT agent concentration, its effect on the polymer properties was studied. It turns out that the conversion at the gel point increases when RAFT agents are used. Similarly, a decrease in the relaxation temperature is noticed as well as an increase in the homogeneity of the polymer network. Due to the reduction of internal defects, this leads to better mechanical properties as exemplified by toughness measurement of 3D printed samples.