Adsorption of cationic copolymer nanospheres onto cotton fibers investigated by a facile nephelometry

A facile nephelometry for measuring very low nanosphere concentrations was established by using a very common nephelometer in order to monitor the adsorption of polymer nanospheres from liquid phase onto cotton fiber surfaces. Monosized nanospheres of 40 nm were prepared by cationic emulsion polymerization of styrene and methyl acrylate with a polymerizable emulsifier, methacryloxyethyl hexadecyl dimethylammoniumbromide. The turbidity of aqueous suspension liquid decreased rapidly within the first contact time of 50 min for CMC-modified cotton fibers. The maximum amount of nanospheres deposited on CMC-modified cotton fibers was 15 mg per gram fibers, far higher than the amount of 4.8 mg per gram fibers on unmodified cotton fibers. The adsorption of cationic nanospheres on cotton fibers followed the Langmuir adsorption model. SEM observation reveals that a uniform mono-layer of nanospheres presented on CMC-modified cotton fiber surfaces.