He has established an international reputation in the field of 'living' radical polymerization to create complex polymer architectures, including dendrimers, cyclic polymers and polymer nanostructures in water. His work focuses on building designer polymers for various biomedical applications, including vaccines, drug delivery, and stem cells.

His work on nitroxide radical trapping resulted in a ‘click’ -type reaction and trapping of small radical intermediates in polymerization systems. Determining kinetic parameters, including rate constants for propagation (kp), transfer (ktr) and the complex termination (kti,j), have allowed modelling of conventional and ‘living’ radical polymerizations and determine important mechanistic steps. For example, we proposed the intermediate radical termination (IRT) step in RAFT polymerization. His group at Eindhoven University of Technology was the first to study and synthesize polymer nanoparticles in water with controlled composition and morphology using the RAFT technology. He worked with Professor Virgil Percec (University of Pennsylvania) in 2001 on SET-LRP.