<span lang="EN-GB">Physicochemical Characterization of Synergistic Bitumen Modified with Date Palm-Derived Lignin and Fumed Silica Nanoparticles

In this investigation, bitumen was modified with a sustainable bio-modifier derived from soda lignin from the Date Palm Frond Base (DPFB) and used in conjunction with Fumed Silica (FS), which served as a nano-reinforcing agent. Characterization techniques performed on the extracted lignin (FT-IR, ¹H NMR, and XRD) indicated the presence of functional groups and an amorphous structure suitable for modifying bitumen. Bitumen was modified with ۳۰ wt.% soda lignin and with varying amounts of FS from ۱ wt.% to ۱۰ wt.%. The introduction of lignin significantly improved high-temperature performance, as demonstrated by a decrease in penetration (from ۶۵ to ۴۴ mm), an increase in softening point (۴۸–۵۸ °C), and an increase in viscosity (۹۸۰–۱۰۷۹ cP). The reduction in ductility (approx. ۴۰%) signifies increased rigidity but also indicates that the addition of both lignin and fumed silica created a synergistic interaction, whereby lignin stiffened the binder and fumed silica improved the structural stability and dispersion of the additives within the binder. The effects of this interaction on the softening point (an increase of approximately ۱۱ °C) and the increase in viscosity (approximately ۲۰۰ cP) suggest that combining a bio-based polymer and an inorganic nanomaterial results in a balanced modified system when bio-growth and/or biocompatibility are integrated into the asphalt binder. The resultant system exhibits improved thermal and mechanical performance. Therefore, this methodology has potential as an environmentally friendly alternative to traditional modifier products to improve pavement durability.

کلیدواژه ها:

DPFB ، soda lignin ، Ductility ، Fumed silica ، ۱H NMR