Bayhydrol A 242 Polyacrylic Resin Bayer MaterialScience Acrylic Resins Soluble in water Partially soluble in glycol ether Bayhydrol A 242 is water-thinnable polyacrylic resin containing hydroxyl groups. It is used as a coreactant for Bayhydur® and Desmodur® N polyisocyanates in the formulation of aqueous twocomponent polyurethane systems for various applications by brush, roller or spray. Form supplied is white emulsion, approximately 42 % in water. Bayhydrol A 242 is a water-thinnable hydroxyfunctional polyacrylic resin with emulsifying properties. It can be neutralized with ammonia. Given the special composition of this product, both hydrophilic polyisocyanates, such as Bayhydur 3100, and hydrophobic grades, such as Desmodur N 3400 and others, are suitable co-reactants. The resultant water-thinnable two-component system cures to yield a polyurethane film with good general properties. Only a small-scale polyurea reaction takes place. Suitable auxiliaries include: Thickener to adjust the formulation to the optimum application viscosity De-aeration agent and antifoam Conservation agent Polyacrylic resin.