RT Journal Article
T1 Influence of the prepolymer molecular weight and free isocyanate content on the rheology of polyurethane modified bitumens
A1 Carrera Páez, Virginia
A1 Cuadri Vega, Antonio Abad
A1 García Morales, Moisés
A1 Partal López, Pedro
AB Isocyanate-based modification is lately gaining acceptance as a successful way to give added value to bitumen, a crude oil refining by-product. In order to study the influence of prepolymer type on the rheological properties of the resulting binders, six prepolymers synthesized from polypropylene-glycols (PPG) with varying molecular weight (between 440 and 2425) and different molar excess of a polymeric MDI (4,4’-diphenylmethane diisocyanate) were used. Two modification procedures, either involving or not water addition were followed. The modification achieved depends on both the selected polyol molecular weight and the excess in MDI (i.e., free isocyanate content), although not in a similar extent. Viscous flow and dynamic oscillatory shear tests, at 60 ºC, demonstrated a much higher level of bitumen modification by using the prepolymer prepared with the polyol having a molecular weight of 940 and with a free isocyanate content of 17.4 wt.%, mainly after addition of water. On the other hand, bitumen nature greatly affects the final rheological properties of these bituminous products. In that sense, modification results much more effective when conducted on bitumen with a well-developed colloidal microstructure.
PB Elsevier
SN 1873-1945 (electrónico)
YR 2014
FD 2014
LK http://hdl.handle.net/10272/12106
UL http://hdl.handle.net/10272/12106
LA eng
NO Carrera Páez, V., Cuadri Vega, A.A., García Morales, M., ARCIA-MORALES, M., Partal López, P.: "Influence of the prepolymer molecular weight and free isocyanate content on the rheology of polyurethane modified bitumens". European Polymer Journal. Vol. 57, págs. 151-159, (2014). DOI: 10.1016/j.eurpolymj.2014.05.013
NO This work is part of two research projects sponsored by a MEC-FEDER Programme (Research Project MAT2007-61460) and by a Junta de Andalucia Programme (TEP6689). The authors gratefully acknowledge their financial support. A.A. Cuadri also thanks “Ministerio de Educación” for the concession of a F.P.U. research grant (AP2008-01419).
DS Repositorio Institucional de la Universidad de Huelva
RD 30 may 2026