engleski

Relationship between fractal, viscoelastic, and aging properties of linear and radial styrene–butadiene–styrene polymer-modified bitume

Morphology and interface of the polymer and bitumen is evaluated in linear SBS-L styrene- butadiene-styrene block copolymer , and radial SBS-R block copolymer modified bitumen (PmB) by fractal analysis. Fluorescence microscopy technique coupled with image analysis was used to measure the particle size distribution and fractal dimension of polymer modified bitumen morphology formed in mixtures. Fractal analysis approach was proposed as quantitative description method to evaluate non-uniformity of phase separated SBS polymer particles/ fibrils in PmB. Fractal-like structures in fluorescence micrographs of PmB morphology with the polymer phase separated particles/fibrils were quantified using interface D[BW], bitumen-rich phase D[B+BW] and SBS-rich phase D[W+BW] box-counting fractal dimensions. The over-all morphology structure became more compact or more fibril organized as the polymer content attained over-critical values. The relatively high values for the bitumen-rich phase D[B+BW] fractal dimension suggests that the polymer modified bitumen mixtures have a structure with extremely high space-filling capacity. The polymer bitumen mixtures properties by the conventional laboratory performance tests and by the rheological measurements before and after the Rolling Thin Film Oven Test, RTFOT have been correlated with the PmB mixtures fractal dimensions.

SBS ; polymer modified bitumen ; rheology ; fractal ; ageing

nije evidentirano