SILICIUM-BASED NANOCOMPOSITE MATERIALS FOR FOOD PACKAGING APPLICATIONS

Nanotechnology is one of the growing technologies in diverse applications including food packaging. Principle of nanotechnology is based on combination of diverse materials (incorporation of organic or inorganic nanoparticles into polymer matrix) for improvement in materials properties (mechanical, barrier, optical, thermal). As new class of materials, polymer nanocomposites are materials containing at least one component on nanodimension (1-100nm). Because of very small particle size and high surface area of nanoparticles, interactions between polymer matrix and the filler is enhanced. There are three different types of nanoparticles, depending on their shape: layered (one dimensional), nanotubes (two-dimensional), and spherical (three dimensional) nanoparticles. Influence of addition of nanoparticles to different polymeric systems depends on their distribution and dispersion in polymer matrix. Spherical silica nanoparticles are naturally abundant, with high thermal resistance, low moisture adsorption, excellent dispersion, and ability to adjust rheological behavior as well as low cost, thus are very suitable for diverse application. In unmodified form, they are hydrophilic, and this can be challenging from the point of dispersion and distribution (also affecting the level of improvement in material properties). However, they can be easily modified, and transformed in hydrophobic form, with different chemical reactions (blocking the free -OH group, and lowering the tension between particles). Nanoscience is giving a completely new approach to development of composite materials, because incorporation of only small amounts of nanoparticles resulting in great improvements in divers properties This chapter will give an overview on different nanocomposite systems based on silica nanoparticles with improved properties for food packaging application.