Abstract: A promoted membrane suitable for use in single-ply roofing applications is disclosed. The membrane comprises EPDM rubber and 0.1 to 10 wt. % of an adhesion promoter. The promoter comprises a polyester resin having a hydroxyl number within the range of 28 to 250 mg KOH/g, a content of terephthalate recurring units within the range of 40 to 65 wt. % based on the amount of polyester resin, and a glass-transition temperature within the range of 40° C. to 80° C. Roofing systems comprising the promoted EPDM membranes are also disclosed. Compared with an unpromoted membrane, the promoted membranes provide a substantial and unexpected boost in peel strength such that the roofing systems resist weather-induced failure of the bond between the roofing membrane and the roof substrate. The invention helps roofers minimize or limit the aggravation and cost of warranty claims from customers whose buildings and contents may otherwise be damaged or destroyed by exposure to wind and/or rain.

Abstract: A promoted membrane suitable for use in single-ply roofing applications is disclosed. The membrane comprises EPDM rubber and 0.1 to 10 wt. % of an adhesion promoter. The promoter comprises a polyester resin having a hydroxyl number within the range of 28 to 250 mg KOH/g, a content of terephthalate recurring units within the range of 40 to 65 wt. % based on the amount of polyester resin, and a glass-transition temperature within the range of 40° C. to 80° C. Roofing systems comprising the promoted EPDM membranes are also disclosed. Compared with an unpromoted membrane, the promoted membranes provide a substantial and unexpected boost in peel strength such that the roofing systems resist weather-induced failure of the bond between the roofing membrane and the roof substrate. The invention helps roofers minimize or limit the aggravation and cost of warranty claims from customers whose buildings and contents may otherwise be damaged or destroyed by exposure to wind and/or rain.