Vegetable-oil-based polyurethane modified asphalt and mixture containing vegetable-oil-based polyurethane modified asphalt

Abstract

The invention discloses vegetable-oil-based polyurethane modified asphalt, which is prepared by the following method: 1) synthesis of a vegetable-oil-based polyurethane prepolymer, to be more specific, at room temperature and in presence of nitrogen for protection, adding a polymerization inhibitor into a reaction vessel, adding liquefied MDI according to isocyanate index R, stirring for 2 to 8 minutes, dropwise adding castor oil, and continuing to react for 40-60min; 2) composition of the modified asphalt, to be more specific, the modified asphalt comprises 10 to 45 parts of the synthesized vegetable-oil-based polyurethane prepolymer, 90 to 50 parts of asphalt and 0 to 5 parts of other additives. The invention also provides a mixture containing the modified asphalt. The vegetable-oil-based polyurethane modified asphalt can be synthesized at room temperature and under the condition of heat brought by long time stirring due to high degree of functionality of vegetable oil polyols, in maintenance formation process, the vegetable-oil-based polyurethane modified asphalt can be secondarily reacted with air and active hydrogen groups in the asphalt, so that the strength of the mixture containing the modified asphalt is further enhanced, the service life of an asphalt pavement can be prolonged, and prospects are great.

Description

technical field [0001] The invention belongs to the field of road engineering, and in particular relates to a modified asphalt and a mixture containing high molecular polymers. Background technique [0002] Polyurethane is an organic polymer inlaid with soft and hard segments. The difference in polarity between the hard segment and the soft segment and the crystallinity of the hard segment itself lead to the incompatibility of the soft and hard segments, and two phases similar to SBS can occur. phase-separated structure. The hard segment after curing of polyurethane provides a certain strength for the material, and at the same time, the soft segment makes the material have corresponding flexibility. Its application in the asphalt system can improve the high and low temperature performance of the base asphalt. [0003] As a natural renewable energy source, vegetable oil is cheap and abundant. Using castor oil instead of petroleum-based polyols can reduce the production cost ...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent CN102617070A discloses a polyurethane asphalt concrete and its preparation method and application. The polyurethane prepolymer is prepared by reacting isocyanate, polyol compound, catalyst and plasticizer as raw materials, and is cold-mixed and paved with diluted asphalt The polyurethane asphalt concrete mixture prepared by this method has excellent performance, but its polyurethane prepolymer synthetic raw materials are all non-renewable petroleum resources, and must contain catalysts, plasticizers and other additives, and the synthesis temperature is as high as 80-90 °C

The 60°C Marshall stability of its composite modified asphalt concrete meets the requirements of the EA-10 specification for epoxy asphalt concrete, but the addition of additives is complicated, and the high strength of the mixture mostly depends on the rigidity and high strength of epoxy asphalt.

[0006] The above-mentioned published patents all involve the relevant performance of polyurethane modified asphalt mixture, but they are all mixtures formed on the basis of petroleum-based polyols and many additives that can improve the performance of asphalt. However, the composition and preparation of polyurethane-modified asphalt mixtures synthesized from vegetable oil polyols have not been reported yet.

Images