With the aim of improving the durability and safety

erosion time

and cost-effective of asphalt road

a composite of modified calcium sulfate whisker-styrene butadiene rubber modified asphalt (MCSW-SBRMA) was prepared

via

thermal doping. Firstly

stearic acid and titanate coupling agent (NDZ-201) were used as a modifier to transform calcium sulfate whisker (CSW) into MCSW

via

wet modification method at 60 ℃ and anhydrous ethanol as a dispersant. What is more

the optimum loading of modifier (a mixture of 25% stearic acid + 75% NDZ-201) was found to be at 2% to prepare MCSW. Subsequently

a composite of MCSW-SBRMA was prepared with different loading of MCSW (

i.e

. 2% to 8%) to enhance the softening point of asphalt. In this study

it was found that 4% of modifiers was the best composition to improve the MCSW-SBRMA properties as elucidated in the orthogonal experiment table L

16

(42). The effects of MCSW and SBR addition on several properties of asphalt were studied by multiple routine tests including penetration

segregation test

and so on. The results show that: 2% to 8% MCSW can increase the softening point of SBR modified asphalt (SBRMA) by 7% to 8%. 4% MCSW increased the PG of SBRMA from 64 to 70

which greatly improved the high temperature characteristics of asphalt. The 5 ℃ ductility of MCSW-SBRMA is greater than 100 cm

which greatly improves the low temperature performance of asphalt. Through the application of fluorescence microscopy

(FM)

Fourier transform infrared spectroscopy (FTIR)

Scanning electron microscopy (SEM)

and energy dispersive spectroscopy (SEM-EDS)

it has been demonstrated that MCSW-SBR effectively alters asphalt in a highly uniform manner

with some MCSW still retaining large cross sections

thereby facilitating the dispersion of shear stress and enhancing the durability of asphalt.