WATERBONE CASEIN/ACRYLIC NANOPARTICLES

M.L. PICCHIO; R.J. MINARI; J.R. VEGA; M.J. BARANDIARAN; L.M. GUGLIOTTA

Pisa

Congreso; European Polymer Congress (EPF 2013); 2013

European Polymer Federation (EPF) and the Italian Association of Polymer Science and Technology (AIM)

Casein had long been used as principal binder in leather finishing and paper coatings for its good stained acceptance, finishing glazed aspect and good substrate penetrability [1]. However, casein films present susceptibility to microbial attack, and poor mechanical properties. For this reason, the casein grafting aims to modify the properties of such protein on the basis of a synergetic combination with other polymeric materials. In this work the emulsion polymerization of acrylic monomers (butyl acrylate/methyl methacrylate, BuA/MMA) in the presence of casein was investigated with the objective of producing waterborne casein/acrylic nanoparticles with controlled microstructure and nanomorphology able to be applied as coatings and/or adhesives partially biodegradable and with improved properties. The redox initiation system, involving tert-butyl hydroperoxide (TBHP) and amine casein [2] was adopted in this work. Polymerizations of BuA/MMA in the presence of variable amounts of casein (from 3 to 50 %wbm, weight based on monomer) were carried out in batch at 80ºC. Polymerization kinetics, molecular microestructure of the casein-acrylic nanoparticles, and the films properties from the synthesized lattices are discussed. Compatibilized waterborne acrylic/casein nanocomposites with improved film properties (mechanical and adhesive, transparency and flexibility) were successfully synthesized.