Improvement of the mechanical properties of paper by starch coatings modified with sepiolite nanoparticles.

The modern and rapidly developing paper and board industry requires more efficient agents for the surface of paper in order to improve the mechanical properties. The starch coating used for the reinforcement of schrenz (110 g/m2) contained ultrasonicated nanoparticles of the mineral sepiolite. The viscosity of starch dispersions modified with different concentration of sepiolite was followed at the temperature of the coating on schrenz. The values of the breaking length, bursting strength and CMT-strength of the paper reinforced with modified starch were increased by up to 20%. The viscoelastic properties as storage modulus were increased, too. Scanning electron microscopy of the samples showed deagglomeration and homogeneity of the sepiolite nanoparticles. [ABSTRACT FROM AUTHOR]