Effect of compatibilizer on morphology, rheology and properties of SEBS/clay nanocomposites

In this study, a nanocomposite of poly (styrene - (ethylene-co-butylene) - styrene) triblock copolymer (SEBS) and an alkyl phosphonium salt-intercalated organic montmorillonite (HMMT) blend was prepared by melt-mixing. The effect of the compatibilizer maleic anhydride-grafted SEBS (SEBS-MA) on structure, morphology and rheological behavior of the SEBS/HMMT nanocomposites were studied. Better dispersion of HMMT domains in SEBS matrix was achieved after adding 7 wt% SEBS-MA, with increased transparency and surface hydrophobicity. The prepared SEBS/HMMT/SEBS-MA nanocomposite displayed significantly improved mechanical, thermal stability and gas barrier properties, which can be attributed to its unique morphology and changed microphase separated structure. These superior properties of the SEBS/nanoclay nanocomposite are important for both biomedical and packing applications.