Investigation of the effect of filler shape and content on the permeability of latex films

Permeability has become an important issue in packaging, electronic and corrosion industry. Water vapor permeability (WVP) has been studied more due to its construction and compressibility. In order to study the effects of the content and shape of filler on WVP of water-based coatings, 3 types of filler with different geometric structure namely S220, Z110 and talc in acrylic resin (P145) were used. To investigate the effect of the elasticity, mixtures of water-based resins with different glass transition temperature (Tg), PS2 and P145 at different compositions prepared. The results showed that with different filler contents in latex film, permeability changed based on the shape of fillers. That means, the increase in pigment volume concentration of S220 and Z110 caused increase in permeability, but talc showed reduce in permeability due to increased penetration path. Also increasing resin with high Tg, less than 45 wt%, increased permeability.