Processes for producing filter cartridge assemblies and molded polyurethane elastomers

A process for producing a molded polyurethane elastomer, comprising depositing a non-foaming reaction mixture into a mold, the non-foaming reaction mixture comprising:

• (a) an organic polyisocyanate prepolymer having an internal mold release agent;
• and
• (b) an isocyanate-reactive composition comprising:
• (i) 1% to 10% by weight, based on the total weight of isocyanate-reactive ingredients in the isocyanate-reactive composition, of a polyether tetrol that is an alkylene diamine-alkylene oxide adduct having a number average molecular weight of 150 to 500 gram/mole;
• (ii) a polyether polyol that has a hydroxyl functionality greater than 2 and a number average molecular weight of 150 to 500 gram/mole, wherein the polyether polyol is prepared from an initiator which is not an amine;
• and
• (iii) 40 to 80 percent by weight, based on the total weight of the isocyanate-reactive composition, of a polyether polyol having a functionality of 3 and a number average molecular weight of 600 to 800 gram/mole,
• wherein the polyether tetrol (i) and the polyether polyol prepared from an initiator which is not an amine (ii) are present in the isocyanate-reactive composition in a relative weight ratio of 2:1 to 4:1.