Sharif Digital Repository

Modification by crumb rubber is a useful means of improving the resistance of asphalt binders and mixtures against rutting, fatigue cracking, and low temperature cracking. Increase binder viscosity and decrease stability at high temperatures are accompanied by most modifiers, and crumb rubber is no exception. Recent research efforts have shown that development of cross bonds across polymer chains and sulfur can improve the storage stability of modified binders. Also, WMA additives can considerably decrease the binder viscosity. This research showed that addition of small amount of sulfur during the crumb rubber modification can improve the workability and storage stability of this binder.... 

Hyperbranched copolymers are highly attractive due to their unique properties, such as tunable structure and surface functionality, making them versatile for applications in biotechnologies, pharmaceuticals, and materials engineering. Glycidol, as a reactive monomer with excellent biocompatibility, combined with sulfur, which enhances mechanical and chemical properties, represents a promising combination for hyperbranched copolymer synthesis. In this study, hyperbranched glycidol-sulfur copolymers were synthesized using cationic and anionic ring-opening polymerization methods. FT-IR analysis confirmed the successful incorporation of S-S bonds and sulfur-containing functional groups into the...