To provide a method for manufacturing a (co)polymer latex having a small (ultrafine) particle size.
Ultrafine particles of a hydrophobic latex polymer or copolymer are manufactured by means of free radical emulsion polymerization, wherein at least one compound selected from the group consisting of a dimer and a cobalt complex acting as a chain transfer agent(CTA) is utilized for polymerizing or copolymerizing a monomer or monomer mixture respectively, so that the latex particles have an average particle size of less than 100 nm, which is not less than 10% smaller than that of the particles when they are prepared in the absence of the CTA. The polymerization is carried out as a water-based reaction in the presence of the CTA and a surfactant. The concentration of the surfactant is 5-25 wt.% per the monomer or monomer mixture when it is a nonionic surfactant, and 0.05-10 wt.% on the same basis when it is an ionic surfactant.
VERMEERSCH JOAN
THILLO ETIENNE VAN
HUYBRECHTS JOS
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