The paper/board manufacturers target to replace the current oil-based products. Earlier VTT has developed starch and later hemicellulose based dispersions for paper coating applications. Now VTT has proven competence to polymerize novel latexes and test their performance in coating application. The emulsion polymerizations had two aims: to produce SB-type products for the coating application in which the styrene monomer is replaced with alternative monomers.
It was demonstrated how methylstyrene can replace styrene in preparing styrene-butadiene type latexes and to compare the properties of the paper coating of the prepared methylstyrene-butadiene emulsion with the commercial styrene-butadiene latex reference sample. The measured paper properties for uncalandered and calandered coated samples, methylstyrene proved to be adequate for replacing the oil based styrene in commercial reference SB latexes. Coating colours containing methylstyrene seem to have an improved water retention compared to the reference styrene-butadiene latex coating colour and the laboratory prepared styrene-butadiene coating color.
Tags: emulsion polymerizations, methylstyrene, coating, latex
Source: ForestTech, 2012-04-30.