Development of Bio-Based Polymers for Use in Asphalt, TR-639, 2014

(2014) Development of Bio-Based Polymers for Use in Asphalt, TR-639, 2014. Transportation, Department of

pdf
Preview
PDF
Iowa_DOT_InTrans_TR-639_Bio-Based_Polymers_Asphalt_2014_Final.pdf

File Size:1MB
pdf
Preview
PDF
TR 639 Tech Brief .pdf

File Size:281kB

Abstract

Asphalt binder is typically modified with poly type (styrene-butadiene-styrene or SBS) polymers to improve its rheological properties and performance grade. The elastic and principal component of SBS polymers is butadiene. For the last decade, butadiene prices have fluctuated and significantly increased, leading state highway agencies to search for economically viable alternatives to butadiene based materials. This project reports the recent advances in polymerization techniques that have enabled the synthesis of elastomeric, thermoplastic, block-copolymers (BCPs) comprised of styrene and soybean oil, where the “B” block in SBS polymers is replaced with polymerized triglycerides derived from soybean oil. These new breeds of biopolymers have elastomeric properties comparable to well-established butadiene-based styrenic BCPs. In this report, two types of biopolymer formulations are evaluated for their ability to modify asphalt binder. Laboratory blends of asphalt modified with the biopolymers are tested for their rheological properties and performance grade. Blends of asphalt modified with the biopolymers are compared to blends of asphalt modified with two commonly used commercial polymers. The viscoelastic properties of the blends show that biopolymers improve the performance grade of the asphalt to a similar and even greater extent as the commercial SBS polymers. Results shown in this report indicate there is an excellent potential for the future of these biopolymers as economically and environmentally favorable alternatives to their petrochemically-derived analogs.

Item Type: Departmental Report
Keywords: Asphalt, Polymer asphalt, Soybeans, Styrene butadiene styrene, Biopolymers, Soybean oil, Styrenic block copolymers
Subjects: Transportation > Pavements
Transportation
Transportation > Research
ID Code: 16328
Deposited By: Leighton Christiansen
Deposited On: 12 Mar 2014 19:29
Last Modified: 17 Jan 2018 19:01
URI: http://publications.iowa.gov/id/eprint/16328