Patent ID: 7393891

Claim:
A method of manufacture of dried powder of a graft copolymer latex comprising the steps of: manufacturing the graft copolymer latex, which comprises the steps of: manufacturing a seed polymer by polymerizing 1 to 15 parts by weight of one or more monomers selected from said group of vinylaromatic compounds, vinylcyan compounds, and compounds containing the units derived from methyl methacrylate, 0.01 to 0.5 parts by weight of a cross-linking agent, and 0.01 to 0.5 parts by weight of a grafting agent, based on 100 parts by weight of the total monomer used for the manufacture of the graft copolymer latex; manufacturing a core polymer by polymerizing 20 to 70 parts by weight of an alkyl acrylate monomer, 0.1 to 1 part by weight of a cross-linking agent, 0.05 to 0.5 parts by weight of a grafting agent, and 0.05 to 2 parts by weight of a surfactant in the presence of the seed polymer, based on 100 parts by weight of the total monomers used for the manufacture of the graft copolymer latex; and manufacturing a graft shell polymer by polymerizing 20 to 60 parts by weight of a vinylaromatic compound, 10 to 30 parts by weight of a vinylcyan compound, and 0.05 to 2 parts by weight of a reactive surfactant having double bonds capable of reacting with a monomer during the polymerization, in the presence of the core polymer, based on 100 parts by weight of the total monomers used for the manufacture of the graft copolymer latex; and manufacturing the dried powder, wherein said graft copolymer latex manufactured in said steps of manufacturing of the graft copolymer latex is sprayed and dried.