Novel multifunctional polymeric photoinitiators and photo-coinitiators derived from hyperbranched polyglycerol

A new class of hyperbranched PPIs and PPCs have been prepared. The introduction of compatibilizing groups such as MEEA or trimethylacetate enhanced their solubility in radiation-curable formulations and led to an improved photoactivity compared with the corresponding MPI and MPC. Although the molecular weights of the subject PPIs and PPCs exceeded 800 g.mol(-1), the viscosities of the radiation-curable formulations were still suitable for inkjet application. The combination of high photoactivity, low viscosity, and low extractability after curing rendered the resulting hyperbranched PPIs and PPCs attractive as components in the inkjet ink for inkjet printing, e.g., in food packaging.