STYRENE-MONTMORILLONITE HYBRID NANOCOMPOSITE CHEMICALLY MODIFIED WITH DIALYL DIMETHYL AMMONIUM CHLORIDE, WITH HIGH MECHANICAL PROPERTIES AND IMPROVED FLAME PROPERTIES

Abstract

Polystyrene, the fourth most widely used polymer globally in the packaging industry, benefits significantly from any improvements in its mechanical and flame-resistance properties. In its conventional form, polystyrene offers a fire resistance of over 180 seconds, classifying it as UL94 HB, which is insufficient according to UL94 safety standards. To overcome these limitations, a hybrid nanocomposite has been developed that incorporates chemically modified montmorillonite with diallyl dimethyl ammonium chloride (DADMAC), facilitating styrene grafting through an emulsion reaction. This process not only optimizes clay dispersion within the crystalline polystyrene matrix but also enhances its properties, achieving a fourfold increase in mechanical strength and reducing the burn time to less than 30 seconds, thus reaching the UL94 V1 rating.The resulting nanocomposite is characterized by effective chemical integration between the polymer and inorganic phases, achieved through chemical modification of the montmorillonite and styrene grafting. This provides a homogeneous and uniformly dispersed structure of montmorillonite within the polystyrene matrix, significantly improving interfacial compatibility and adhesion. This expands the applications of both virgin and recycled polystyrene for high-performance and safety applications, while also complying with polymer recycling regulations.