Rheological Properties of Polyethylene and Polypropylene Modified Bitumen

This paper presents a part of research on the rheological properties of bitumen modified by thermoplastic namely linear low density polyethylene (LLDPE), high density polyethylene (HDPE) and polypropylene (PP) and its interaction with 80 pen base bitumen. As it is known that the modification of bitumen by the use of polymers enhances its performance characteristics but at the same time significantly alters its rheological properties. The rheological study of polymer modified bitumen (PMB) was made through penetration, ring & ball softening point and viscosity test. The results were then related to the changes in the rheological properties of polymer modified bitumen. It was observed that thermoplastic copolymer shows profound effect on penetration rather than softening point. The viscoelastic behavior of polymer modified bitumen depend on the concentration of polymer, mixing temperature, mixing technique, solvating power of base bitumen and molecular structure of polymer used. PP offer better blend in comparison to HDPE and LLDPE. The viscosity of base bitumen was also enhanced with the addition of polymer. The pseudoplastic behavior was more prominent for HDPE and LLDPE than PP. Best results were obtained when polymer concentration was kept below 3%

Authors:

• Noor Zainab Habib
• Ibrahim Kamaruddin
• Madzalan Napiah
• Isa Mohd Tan

Keywords:

• Polymer modified bitumen
• Linear low densitypolyethylene
• High density polyethylene
• Polypropylene.

References:

[1] Whiteoak C.D The shell bitumen hand book. Surrey, UK. 2003.
[2] Didier Lesueur " The colloidal structure of bitumen: Consequences on
the rheology and on the mechanism of bitumen modification". Advances
in colloid and Interface Science, vol. 145, pp. 42-82, 2009.
[3] Gonzalez et al "Rheology and stability of bitumen/EVA blends"
European Polymer Journal, vol.40, pp. 2365-2372, 2004.
[4] Bardesi A, et al. "Use of modified bituminous binders, special bitumens
with bitumen additives in pavement applications". Technical
Committee Flexible Roads (C8) World Road Association (PIARC )
,1999.
[5] Hadidy Al, Qui Tan Yi " Effect of Polyethylene on life of flexible
pavements" Construction and Building Materials vol. 23 pp. 1456-
146,2009.
[6] J.Stastna et al. "Viscosity functions in polymer modified asphalts"
Journal of Colloid and Interface Science, vol. 259, pp.200-209,2002.
[7] Lu.X and Isacsson "Compatibilty and storage stability of styrenebutadiene-
styrene copolymer modified bitumens" Journal of Materials
and Structure, vol.30, pp.618-626,1997.
[8] Yousefi AA, Kadi A AIT "Composite asphalt binders: Effects of
modified RPE on asphalt" Journal of Materials in civil Engineering,
May, pp.113-123, 2000.
[9] Drozdov Aleksey. D, Yuan Q "The viscoelastic and viscoplastic
behavior of low density polyethylene" International Journal of Solid
and Structure, vol. 40, pp2321-2342, 2003.
[10] Sybilski.D "New simplified equation for the computation of absolute
viscosity of polymer-bitumens" Materials and Structure, vol.30, pp.182-
187, April 1997.
[11] Wekumbura et al., "Destruction and Recovery of Internal Structure in
Polymer-Modified Asphalts" Journal of Materials Civil Engineering, pp.
227-232, 2007.
[12] Chen Jian-Shiuh et al. "Asphalt Modified by Styrene-Butadiene Styrene
Triblock Copolymer: Morphology and Modal" Journal of Materials in
Civil Engineering May/June, pp. 224-229, 2002.
[13] American society for Testing and Materials (ASTM), standard
Specification, Section 4, vol. 04-03, 2000.
[14] Traxler "Ashaplt its composition, properties and uses" Reinhold
publishing corporation.Chabman & Hall.Ltd., London.1961.
[15] Bhattacharya Sati N "Rheology Fundamentals and Measurement"
chapter 1, Royal Melbourne Institute of Technology. Australia.1997.