Modified and functionalized maleimide copolymers for paper coatings

New functional aqueous dispersions of poly(styrene-co-maleimide) (SMI) and poly(octadecene-co-maleimide) (OMI) have been prepared by grafting different functional additives into the copolymers side chains to explore the possibility of tailoring the properties of these auxiliary pigments for applications in paper coating formulations. Modifications were carried out by reacting the corresponding maleic anhydride (MA) copolymer with ammonia and small amounts of various functional primary amines such as 4-amino-2,2,6,6,-tetramethylpiperidine (TAD), l (+)-aspartic acid (ASP), 2,2,2-trifluoroethylamine (TFEA) and 2,2,3,3,4,4,4-heptafluorobutylamine (HFBA) to investigate opportunities to fine-tune weathering stability (TAD), adhesion properties (ASP) or hydrophobicity (TFEA, HFBA) of the coated paper board. The thermal imidazation reaction of MA groups was carried out at 155 °C for 6 h in organic solvent-free process using high shear forces. The obtained functional nanoparticles varied in size from 50 to 217 nm and exhibited high glass transition temperatures ( T g ) ranging from 150 to 180 °C. Paper board coating trials are also reported in this article.