Processing, Mechanical and Morphological Properties of GTR Modified by SBS Copolymers

Area of Science:

• Materials Science
• Polymer Chemistry
• Rubber Recycling

Background:

• Ground tire rubber (GTR) presents a sustainable resource for material development.
• Thermoplastic elastomers like styrene-butadiene-styrene (SBS) copolymers can compatibilize and modify GTR.
• Optimizing GTR modification is crucial for enhancing its properties and expanding applications.

Purpose of the Study:

• To investigate the thermo-mechanical modification of ground tire rubber (GTR) using styrene-butadiene-styrene (SBS) copolymers.
• To evaluate the impact of different SBS grades and contents on GTR properties.
• To compare the effectiveness of sulfur-based and dicumyl peroxide cross-linking systems for modified GTR.

Main Methods:

• Thermo-mechanical treatment of GTR in the presence of various SBS copolymers.
• Characterization of Mooney viscosity, thermal stability, and mechanical properties of modified GTR.
• Rheological, physico-mechanical, and morphological analysis of cross-linked GTR/SBS systems.

Main Results:

• Linear SBS copolymer with high melt flow rate demonstrated optimal processing behavior for GTR modification.
• SBS incorporation enhanced the thermal stability of the modified GTR.
• Optimal SBS content was found to be below 30 wt% for economic efficiency.
• Dicumyl peroxide cross-linking resulted in better processability and mechanical properties compared to sulfur-based systems due to co-cross-linking effects.

Conclusions:

• Linear SBS is a suitable modifier for GTR, improving its processability and thermal stability.
• Dicumyl peroxide is a more effective cross-linking agent than sulfur systems for SBS-modified GTR.
• Optimized GTR/SBS composites offer enhanced performance for potential recycling applications.