Communication: (3-Vinylphenyl)azomethylmalonodinitrile (1) contains a vinyl group as well as an azo group is therefore suitable as a monomer, comonomer and,also as an initiator for radical polymerization. If these functions are used in two separate steps, graft copolymers can be achieved via the grafting from method, A simultaneous use of both functions in the presence of different amounts of styrene results in hyperbranched polymers having a tailored degree of branching.