Abstract: A novel process for modification of polyolefines and their copolymers thereof, enables the production of modified PP with minimal deterioration of molecular weight and low gel content PE and their copolymers and with minimal yellowness. The novel compound is comprised of polyolefin resin or a mixture of resins, unsaturated acidic monomer and organic peroxide, together with low volatility polar acrylic co-monomer and low softening point resin, in a continuous reactive reactor The novel process minimizes sublimation of maleic anhydride and improves distribution of monomers and initiator prior to the melting of the polyolefin.