Production of PS/SIBS/KARBON nanotube composites, investigation of thermal and mechanical properties

In the literature, there are some studies in which different styrenic thermoplastic elastomers (SIS, SEBS, SBS etc.) are used together with PS polymer to prepare blend nanocomposites. However, studies on PS blend containing polystyrene-polyisobutylene-polystyrene (SIBS) triblock copolymer were found to be very few. A nanocomposite study using PS/SIBS and carbon nanotube (CNT) filler has not been found. In this study, PS/SIBS blends and PS/SIBS/CNT nanocomposite compounds were prepared in an internal mixer by melt blending method and they were molded in a laboratory type hot press. Detailed morphological, thermal and mechanical properties of the prepared materials were examined in terms of filler loading degree. In the blends, the SIBS elastomer particle size in the PS matrix increased as the SIBS ratio increased, and as expected, the modulus, tensile strength and toughness values of the materials decreased while the impact resistance values increased. It was found that the impact strenght value of the PS blend containing 20% by weight SIBS increased by approximately 530% compared to the neat PS matrix polymer. In the nanocomposites it was observed that the size of SIBS elastomer particles decreased with the increase of nanotube ratio compared to PS20SIBS blend. This result was attributed to the fact that the nanotubes dispersed in the matrix increased the PS viscosity during the process, thus preventing the elastomer phases from coalescing. It was determined that the toughness, modulus and tensile strength values of nanocomposites increased compared to blends, and their impact resistances decreased. It was determined that the toughness, modulus and tensile strength values of nanocomposites increased compared to blends, and their impact resistances decreased. It was found that the toughness value of the nanocomposite containing 5 phr CNT, which is thought to have the optimum composition in terms of mechanical properties, increased by 117% compared to the PS20SIBS blend, and its creep deformation under stress decreased by approximately 40% compared to the blend. The Td50 values at which all the prepared PS20SIBS/CNT nanocomposites lost 50% of their weight and the degradation temperatures at the maximum degradation rates were all found to be higher than the PS20SIBS blend, and therefore it can be stated that their thermal stabilities increased.