Studies of different properties of polystyrene-asphaltene composites

The study of thermal and viscoelastic properties of polystyrene composites with different filler loadings of asphaltenes were carried out. The thermogravimetric analysis revealed that the T₁₀ for neat polystyrene was around 365°C and it increased to 440°C with an addition of asphaltene (3 wt% loading, St3). Further addition of asphaltene also showed an increase in the T₁₀ value compared to the neat polystyrene. The second important parameter from TGA analysis can be seen that the neat polystyrene had a degradation maximum (T₅₀) at around 432°C and St3 composite shows the highest T₅₀ value of 450°C. Differential Scanning calorimetric studies of the composites shows that Tg of polystyrene was around 66°C and St2 composite showed the Tg at the maximum of 69°C, which infers that there was interaction between the filler and the matrix. St3 composite shows higher storage modulus as compared to all others. Addition of asphaltenes improved the storage modulus of polystyrene system due to the compatibility effect, which facilitated better load transfer due to the strengthening of the interphase between the filler and matrix. Loss modulus curves of the polystyrene and composites showed a higher loss modulus than the neat polymer in the whole temperature region. It was concluded that the thermal stability and viscoelastic properties of the polystyrene composites were significantly improved with the addition of asphaltene as filler.