Abstract: This invention relates to a method for graft-copolymerizing vinyl chloride monomer to a polyfluorine resin to produce resins of improved physical properties and processability parameters. The vinyl chloride monomer and polyfluorine resin are first treated in a highly alkaline medium and at a high temperature, and the mixture is stirred. Suspension agent(s), water and an initiator are added to the mixture after the temperature thereof has been lowered. The resultant mixture which has been stirred and homogenized is heated to a temperature at which polymerization is completed. Thereafter the mixture is neutralized, washed, and dried. A product having improved impact strength and resistance to heat and abrasion results.