Patent attributes
A sealant composition for roofing shingles that includes a base asphalt, a linear and/or a radial copolymer, oil, and a wax is provided. The linear copolymer has an A-B di-block or an A-B-A tri-block structure. The radial copolymer may have an (A-B)n radial structure, where n is at least 4, or a tri-block (A-B-A) radial structure having from 4 to 8 arms. Blocks A and B may individually represent (1) styrene and butadiene or (2) styrene and isoprene. The oil is a petroleum-based oil that both “softens” the asphalt and reduces the viscosity of the sealant composition. The wax may be a bis-stearamide wax. Additionally, the sealant composition may be reacted with elemental sulfur to crosslink the copolymer blend. The sealant composition seals at temperatures lower than conventional sealants and promotes the easy release of the shingle from a shingle bundle.
