Methods for modifying the acid value of an unsaturated polyester resin suitable for use in forming toner particles are provided. In embodiments, methods may include contacting at least one unsaturated polyester resin with at least one grafting monomer, polymerizing the graft monomer and unsaturated polyester resin to form a graft copolymer, and then utilizing the graft copolymer to form toner particles by combining the graft copolymer with an optional colorant, at least one surfactant, and an optional wax. Toners produced by these methods are also provided.