PREPARATION OF INDUSTRIAL ASPHALT

摘要

The present invention relates to a method for preparing an industrial asphalt comprising sparging an oxygen containing gas through an asphalt flux in the presence of 0.25 weight percent to about 12 weight percent of a highly saturated rubbery polymer at a temperature within the range of about 400° F. to about 550° F. for a period of time which is sufficient to increase the softening point of the asphalt flux to a value which is within the range of 185° F. to 250° F. and a penetration value of at least 15 dmm to produce the industrial asphalt. The highly saturated rubbery polymer can be a styrene-ethylene/butylene-styrene block copolymer rubber or a highly saturated styrene-ethylene/propylene-styrene block copolymer rubber.

主权项

1. A method for preparing an industrial asphalt comprising (1) heating an asphalt flux to a temperature of at least 120° F. to produce a hot asphalt flux, (2) adding from about 0.1 weight percent to about 10 weight percent of a highly saturated rubbery polymer to the hot asphalt flux, (3) mixing the highly saturated rubbery polymer throughout the hot asphalt flux to prepare a highly saturated rubbery polymer modified asphalt flux, (4) heating the highly saturated rubbery polymer modified asphalt flux to a temperature which is within the range of about 400° F. to about 550° F. to produce a hot highly saturated rubbery polymer modified asphalt flux, (5) sparging an oxygen containing gas through the hot highly saturated rubbery polymer modified asphalt flux for a period of time which is sufficient to increase the softening point of the highly saturated rubbery polymer modified asphalt flux to a value which is within the range of 185° F. to 250° F. and a penetration value which is within the range of 15 dmm to 25 dmm to produce the industrial asphalt.