Patent ID: 7964656

Claim:
A method for forming a vulcanizable composition of matter, the method comprising: (i) providing a polymer cement comprising at least one functionalized rubber, where the functionalized rubber includes an amine or tin functionality; (ii) preparing a cocktail by mixing about 15 to 45 parts by weight of a processing aid, about 5 to 55 parts by weight of an oil, and from about 95 to 45 parts by weight of a solvent, where the processing aid is a mixture of zinc fatty acid salts, or a high-HLB surfactant, or a metal sulfonate; (iii) adding the cocktail to the cement to form a modified polymer cement or latex; (iv) isolating from the modified rubber cement the rubber and at least one processing aid to form a premix; and (v) mixing the premix with carbon black to form a vulcanizable composition, where said step of mixing occurs within a mixer having a net mixing chamber volume of at least about 75 L operated at a fill factor of at least about 50.