Composite of aramid fibre (poly-m-phenylene isophthalamide)thermoplastic elastomers (SEBS): Enhancement of tensile properties by maleated-SEBS compatibiliser

Aramid fibre, poly-m-phenylene isophthalamide (Teijin-Conex), was used to reinforce thermoplastic elastomer, styrene (ethylene butylene) styrene (SEBS). It was found that the moduli at 100 and 300% elongation of the composite increased linearly with increasing fibre loading. On the other hand, tensile strength of the composites decreased as the fibre content was increased. Improvement of interfacial adhesion was carried out by, first, slightly hydrolysing the fibre with sodium hydroxide solution to increase the number of reactive amino end groups and then mixing with the matrix and compatibilizer, maleic anhydride grafted SEBS (MA-g-SEBS), at various concentrations. Tensile strength of the compatibilized composite was found to increase and then level-off at 5 wt% compatibilizer. Fractured surface of composite containing compatibilizer showed more fibre breakage than the uncompatibilized one. Examination of the extracted fibre revealed that some fraction of rubber was chemically bonded to the fibre surface. These results suggest good compatibilizing performance of MA-g-SEBS for the system studied.