Synthesis and characterization of dendritic carbosilane based macrophotoinitiator

A carbosilane dendrimer based macrophotoinitiator (MPI-185) containing benzophenone moiety terminal groups was synthesized by a divergent hydrosilylation/allylation reaction sequence followed by alcoholysis of the silicon chloride end groups. The structure of MPI-185 was characterized by FTIR, ¹H-NMR, ¹³C-NMR, and ²⁹Si-NMR, and its intrinsic viscosity, molecular weight and polydispersity were meassured on by using a GPC complex system. Its reactivity was tested via curing a sensitive epoxy acrylate (EA) resin using FTIR, and the thermal property of films cured was measured by TGA. The results were compared with those of a small molecule photoinitiator (185). It was found that the curring efficiency of macrophoinitiator (MPI-185) was satisfactory, and the thermal degradation temperature of EA resin cured with MPI-185 was also markedly improved.