A new sprayable polyurethane composite technology from BASF Corp., Wyandotte, Mich., is offered as an environmentally friendly, higher performing alternative to unsaturated polyesters for making pleasure-boat and fishing-boat hulls, hatches, and soft trim, as well as aerospace parts. These “P=U=R=E” structural laminating resins are described as “hybrids” that combine the toughness of polyurethane with the use of conventional peroxide initiators for polyesters. BASF’s resins contain no styrene monomer or other solvents, thus generating very low or zero VOC and HAP levels. They reportedly can be sprayed with or without fillers or chopped glass, using existing equipment and tooling with hardly any modification. They also can be used with hand lay-up or closed-mold processes.
The PUR composites boast higher impact resistance and faster production cycles than polyesters. They also have HDTs near 400 F vs. 180 to 250 F for standard polyesters.