PAVEMENT BINDER

摘要

The present invention provides for a method of making storage stable road paving binders by blending a minor amount of a polymer having at least one diene monomer with a major amount of asphalt containing at least 0.3 % by weight of total nitrogen at an elevated temperature such that the components are sufficiently fluid to blend; treating the asphalt-polymer blend using not more than 250 meq of a sulfonating agent per 100 g of asphalt-polymer blend to introduce the corresponding acid functionality into the blend; maintaining the sulfonated asphalt-polymer blend at a sufficiently elevated temperature and stripping the sulfonated blend with sufficient chemically unreactive gas to remove a major fraction of the acid functionality introduced by sulfonation. The invention also provides for the compositions made by the process. These are useful as binders in road paving applications.