Insights into the bulk kinetics of a 2K radical polymerization system based on the copper catalyzed cleavage of diboranes and its perspectives

Many applications of polymer materials, such as adhesives, require a polymerization process at room temperature and ambient atmosphere. In those cases, two-component (2K) systems based on redox initiation truly stand out due to their reliable performance. Herein, we present a deep insight into the polymerization kinetics of a newly developed initiation system based on the copper catalyzed cleavage of diborane compounds, followed by rheology coupled with NIR. The analysis of different diboranes led us to further investigate the diborane concentration dependency and the effects on gel time that can be observed. Furthermore, it is shown that the diborane/Cu system yields polymers with high molecular weight at high double bond conversions. In addition, the perspectives of diborane/Cu initiation for radical polymerization are presented, as various different monomer classes showed excellent reactivity towards polymerization, enabling the great potential of this initiation system for various applications in polymer chemistry.