Comparative analysis of thermal properties of synthetic and natural fibre-reinforced polymeric composites

This study focused on thermal expansion and weight changes of synthetic (carbon and glass) and natural (flax and hemp) fibre-reinforced polymeric (FRP) composite samples. Composite samples with dimensions and weights of approximately 10.270, 4.600, 50.425 mm, and 2.775 g were prepared using melt-mixing compounds and pressing machines. Thermal degradation and viscoelastic properties were evaluated based on thermogravimetric (TGA), differential scanning calorimetric (DSC) and dynamic mechanical analyses (DMA). From the experimental results obtained, the glass FRP composite sample exhibited similar thermal stability with the carbon FRP counterpart at a temperature of 300 ^oC. It can be corroborated by the DSC investigation that the glass FRP sample acted as a thermal barrier. However, DMA confirmed the strong stiffening and damping effects of glass and carbon FRP composites because both samples possessed a high glass transition temperature of 106 ^oC, demonstrating composites with a high tan delta energy dissipation. TGA showed that carbon FRP composite was a strong material with a mass of 9 mg at 500 ^oC, while flax FRP sample lost significant weight over 100 ^oC. Both glass and carbon FRP composites exhibited a better and more significant thermal resistance than flax and hemp FRP samples, indicating higher thermal efficiency of carbon and glass FRP samples when compared with flax and hemp FRP biocomposites. Therefore, synthetic (glass and carbon) FRP composites are recommended for engineering applications where heat transfer is inevitable, considering their recorded thermal properties compared with other natural FRP biocomposites.