Polyurethane adhesives for reverse osmosis modules

An adhesive composition comprising:

• a first part comprising:
• an isocyanate group-containing prepolymer comprising a reaction product of a first isocyanate and at least one polyol;
• and
• a second isocyanate that is essentially unreacted with the first isocyanate, the at least one polyol, and the isocyanate group containing prepolymer, wherein said second isocyanate may be the same or different than the first isocyanate;
• a second part comprising at least two polyols;
• and
• from 0.5 to 35 weight percent of a plasticizer, based on the total weight of the adhesive composition, wherein the plasticizer is selected from the group consisting of dicarboxylate esters, tricarboxylate esters, benzoates, dibenzoates, epoxidized vegetable oils, esters of soybean oils, phthalates, phosphate esters and combinations of thereof;
• wherein the adhesive composition is essentially free of diluent oils and solvents, wherein the first part of the composition has a total NCO content of 10 to 35 weight percent, based on the total weight of the first part, as measured in accordance with ASTM D2572.