Facile Preparation of Polysiloxane-Modified Asphalt Binder Exhibiting Enhanced Performance

Area of Science:

• Materials Science
• Polymer Chemistry
• Civil Engineering

Background:

• Polymer-modified asphalt enhances pavement performance.
• Modern asphalt pavements require advanced material properties.

Purpose of the Study:

• To develop and characterize a novel polysiloxane-modified asphalt.
• To evaluate the performance improvements of the modified asphalt.

Main Methods:

• Hydroxy-terminated polysiloxane (HO-PDMS) mixed into base asphalt at 140 °C.
• Characterization using FT-IR, GPC, DSC, fluorescence microscopy, and segregation tests.
• Performance evaluation via Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR).

Main Results:

• HO-PDMS chemically bonds with asphalt, ensuring compatibility and stability.
• Modified asphalt exhibits improved low- and high-temperature properties, thermal stability, and hydrophobicity.
• Lower glass transition temperature (Tg) of -12.8 °C, higher rutting parameter, and optimal stiffness/creep rates at specific HO-PDMS dosages.

Conclusions:

• Polysiloxane-modified asphalt offers superior performance compared to conventional asphalt.
• The modified asphalt is suitable for demanding asphalt pavement applications, particularly those requiring resistance to temperature fluctuations.