| Abstract: | Biodiesel is considered one of the best alternative fuel sources in the transportation industry, but it has shown aggressive characteristics on materials that are used in fuel storage and delivery systems in vehicles. In this study, the effect of biodiesel (B100) on the properties of two polyamide‐6‐based semicrystalline polymers was studied and compared with that of diesel and a 20/80 blend of biodiesel and diesel (B20). Experiments were conducted using room temperature immersion tests in the three fuels for 720 h followed by postimmersion thermal and mechanical tests. In all three fuels, the polymers exhibited non‐Fickian weight increase during immersion and did not achieve equilibrium level of absorption in 720 h. The glass transition temperature (Tg), yield and tensile strengths, storage modulus, and peak tan δ decreased after immersion, while the degree of crystallinity and loss modulus increased. Fourier transform infrared spectroscopy study showed that no chemical changes occurred due to immersion. It is concluded that all three fuels absorbed into the polymers acted as plasticizers which caused the observed changes in the properties of the two polymers investigated in this research. POLYM. ENG. SCI., 59:1445–1454 2019. © 2019 Society of Plastics Engineers |
