Effect of SBS on Rheological Properties of Different Base Asphalts

Abstract

In this note rheological properties of two different polymer modified asphalts (PMA) are compared. PMAs were prepared from two different base asphalts, a soft one (200/300 Pen grade) and a hard one (70/100 Pen grade), by addition of 4% by weight of radial SBS as modifier. Dynamic mechanical properties were determined in a wide temperature range for bases and modified asphalts both before and after artificial aging. As expected, the moduli of the soft base are more sensitive to polymer addition and the two PMAs attain similar maximum values after aging. However a significant difference in the frequency at which the maxima of the loss modulus are reached is maintained within the two materials irrespectively of aging or polymer addition.

Morphology and rheological behavior of maltene–polymer blends. I. Effect of partial hydrogenation of poly(styrene‐block‐butadiene‐block‐styrene‐block)‐type copolymers

“…1,3 From a rheological perspective, asphalt also constitutes a highly complex material, varying from a viscous character to an elastic character according to the loading time and temperature. 4 At low temperatures or high loading frequencies, conventional asphalt behaves as a glasslike, elastic solid, whereas at high temperatures or low loading frequencies, it behaves as a viscous fluid.…”

“…17,19,20 The volume fraction of the polymer-rich phase could reach up to 9 times its initial volume, 9,20,21 and for that reason, the addition of relatively small amounts of the polymer ($3 wt %) significantly changes the rheological properties of the asphalt. 1,4,10 The polymer-rich phase is considered a three-dimensional thermoplastic network composed of nodules of polystyrene blocks interconnected through the malteneswollen polybutadiene blocks, 1,7,9,22 being similar to that of neat SBS. Thus, PMAs with SBS consist of a polymer-rich phase and an asphaltene-rich phase both embedded in maltenes, and the morphology and rheological behavior of the PMAs are determined by the relative amounts and characteristics of such phases.…”

“…Examples of such materials are polymer-modified asphalts (PMAs). 1 Asphalt modification is driven by the fact that neat asphalt is a thermoplastic material with relatively poor thermomechanical properties because it is fragile at low temperatures (<À10 C) and soft at high temperatures (>60 C). The thermomechanical properties of asphalt are essentially dependent on its composition.…”

Study of the morphology and rheological behavior of polymer‐modified asphalt blends prepared with poly(styrene‐b‐butadiene‐b‐styrene) and poly(styrene‐b[(butadiene)1—x‐(Ethylene‐co‐Butylene) x]‐b‐Styrene) of Star‐Like Molecular Architecture

“…In general, the polymer should be sufficiently compatible with the asphalt, be cost‐effective, and should resist degradation during mixing, storage, and service . P‐MAs are heterogeneous systems consisting of three macro‐phases: polymer‐rich, asphalt‐rich, and maltenes‐rich . Depending on the composition of the asphalt, the molecular characteristics of the polymer, and the polymer/asphalt ratio, the polymer‐rich phase is either the disperse or the continuous phase of the P‐MA.…”

Comparative study of the effect of sulfur on the morphology and rheological properties of SB‐ and SBS‐modified asphalt

“…Polymer‐modified asphalts (PMAs) are composite materials that overcome the limitations of NA as a result of the addition of polymer. Examples of polymers used in the production of PMAs include natural rubber,10, 11 copolymers of ethylene‐vinyl acetate,12–14 polypropylene,15, 16 styrene‐ethylene‐butadiene‐styrene copolymers,17–19 and styrene‐butadiene copolymers 20–25. PMAs consist of a binary system of polymer‐rich and asphalt‐rich phases, the characteristics of which result from selective interactions between asphalt components and polymer 26…”