HYPERBRANCHED POLYOLS FOR THE DEVELOPMENT OF DURABLE THERMOSET COATINGS

As part of the Air Force program to develop aircraft coating systems with 30 years service life, Aspen Systems, Inc. proposes the development of fracture, chemical weather resistant coatings by incorporation of a hyperbranched polyarylether ketone (HPK) polyol into polyurethane and aliphatic epoxy resin systems. The hyperbranched polyol acts as a chemically and thermally stable thermoplastic toughening agent in the thermoset coatings, imparting high fracture resistance and durability. Hyperbranched polymer co-reactants exhibit low viscosity and high reactivity because of their unique three dimensional structure resulting in low solvent requirements and reduced VOC formulations. They can be prepared readily on large scale for low cost in contrast to the related dendrimer polymers. The high degree of surface functionality allows the properties of the HPK polymers to be readily modified with a variety of hydroxy groups, yielding coatings with easily controllable physical properties. Total hydroxy numbers can also be easily modified to control cross-linking density in the coatings. Aspen Systems has teamed with Valspar Sunbelt Corp., a leader in aircraft coating technology to assist in development of the technology and formulation into a commercial product.