Application of FTIR spectroscopy with solvent-cast film and PLS regression for the quantification of SBS content in modified asphalt

Abstract

ABSTRACTThe quantification of styrene-butadiene-styrene (SBS) in modified asphalt is essential to evaluate the performance of modified asphalt. In this work, Fourier transform infrared (FTIR) spectroscopy with solvent-cast film and chemometrics techniques, partial least squares (PLS) regression, have been implemented to quantitatively analyse the content of SBS in modified asphalt. SBS-modified asphalt with four different SBS content gradient as training samples and specific SBS content as testing sample have been scanned by FTIR spectrometer with solvent-cast film. The spectroscopic data have been measured and analysed using PLS regression. The results indicate that the PLS regression combined with the data pretreatment methods for the quantification of SBS content show good predictability, and wavenumber selection in the mid-infrared region of 1400~800 cm−1 reveals the best calibration models with the more accurate value of determination (4.206%) and the lower standard deviation (0.196), which obviously remove the instability of infrared measurement technology in mid-infrared spectroscope. Therefore, the content of SBS in modified asphalt can be accurately measured using FTIR spectroscopy combined with PLS regression.