Redispersible polystyrene (PS) latexes of particle sizes in the range of 200-220 nm was prepared using low-molecular-weight amphiphilic block copolymer surfactants. Latex powders were obtained by sun drying of the prepared PS latexes and were reintroduced into the solution by simple mechanical agitation/stirring without any additives. DLS and SEM analysis were carried out for pristine/sun-dried latexes to compare the size and shape of the particles. A series of block copolymers with 2-methyl-2-oxazoline and 2-butyl-2-oxazoline or 2-phenyl-2-oxazoline with repeat units 30/20, 60/20, 15/30, and 15/45 were synthesized through cationic ring opening polymerization (CROP) and were used as nonionic surfactants (NIS) in the preparation of poly(styrene) latexes by emulsion polymerization. In this work, we investigated the role of anchoring ability of butyl/phenyl groups of the block copolymer in providing stability and redispersibility of the latex by comparing with simply cetyl and stearyl surfactants that are devoid of such functionality. The ready redispersibility and retainment of size and shape as that of original latexes confirmed the role of anchoring groups. PS latexes prepared by block-copolymer surfactants that are devoid of anchoring units showed lesser stability and no redispersibility compared to anchored surfactants. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48875.
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