From Pre-Swelling to Performance Enhancement: Mechanisms and Effects of an Instant Ultra High-Performance Bituminous...

Area of Science:

• Materials Science
• Civil Engineering
• Polymer Science

Background:

• Traditional high-viscosity modified bitumen requires extensive processing times.
• Instant modifiers offer potential for reduced production cycles in bituminous materials.
• Understanding the modification and pre-swelling mechanisms is crucial for performance enhancement.

Purpose of the Study:

• To elucidate the modification and pre-swelling mechanisms of an instant ultra-high-performance bitumen modifier (SHVE-M).
• To evaluate the contribution of SHVE-M to the performance of modified bitumen (SHVE-MB) and its mixture (SHVE-MBM).
• To compare the performance of instant modified bitumen with conventional wet-process modified bitumen.

Main Methods:

• Systematic characterization using Fluorescence Microscopy (FM), Gel Permeation Chromatography (GPC), physical property tests, viscoelastic properties tests, Dynamic Shear Rheometer (DSR), and mixture pavement performance tests.
• Analysis of modifier morphology and area fraction using ImageJ-win64.
• Evaluation of physical properties (penetration, softening point, ductility), viscoelasticity (viscosity, elastic recovery), and mixture performance (dynamic stability, water stability, low-temperature fracture toughness).

Main Results:

• SHVE-M forms a stable 'bitumen phase-polymer spherical phase' structure with significant modifier area fraction.
• SHVE-MB, prepared in 10 min, shows comparable physical and viscoelastic properties to conventional HVE-MB prepared in 4 h.
• SHVE-MBM demonstrates excellent high-temperature stability, water stability, and superior low-temperature fracture toughness compared to SBS-MBM.

Conclusions:

• The instant ultra-high-performance bitumen modifier (SHVE-M) effectively bridges the performance gap between instant and traditional modified bitumen.
• The pre-swelling mechanism of SHVE-M is well characterized, enabling rapid modification.
• SHVE-M offers a promising alternative for efficient production of high-performance bituminous materials.