Mechanical Properties and Flame Retardancy of Sebs-Based Composites Filled with Aluminium Hydroxide

The flame retardancy and mechanical properties of styrene-ethylene/butylene-styrene block copolymer (SEBS) based composites, containing SEBS blended with a paraffinic hydrocarbon extender oil, copolymer polypropylene (PP), and aluminium hydroxide (ATH) or silane coupling agent surface-treated aluminium hydroxide (m-ATH) were investigated. A maleic anhydride-grafted SEBS (MA-SEBS) was used as a polymer modifier for some composites. As the amount of ATH or m-ATH increased the flame-retardancy of the composites improved, while the tensile strength and elongation at break decreased. When the oil-filled SEBS (O-SEBS) was partially replaced by MA-SEBS, the tensile strength of the composites increased, and elongation at break decreased. Furthermore, replacing O-SEBS with MA-SEBS and treating ATH with silane coupling agent (simultaneously) improved the tensile strength of the composites by a significant margin. The phase structure of the composites was characterised using scanning electron microscopy (SEM) and this revealed that particle-matrix interfacial bonding was improved through the addition of MA-SEBS. The stability of the composites was investigated by thermogravimetric analysis (TGA).