Extended Pot Life and Controlled Cure Marine Coating

Reapplication of corrosion control coatings constitutes a major part of a ship overhaul in both time and resources. Many areas require multiple coats which need time to cure before the area can be recoated or used. One half of a ship’s total overhaul time can be spent waiting for coatings to cure before work can resume. Down time can be reduced substantially through the use of “rapid cure” coatings, which cure in less than 20 minutes. The two components must be mixed immediately prior to application due to their high reactivity, which requires specialized equipment such as metering pumps and mixing chambers. Cost savings are offset by increased training in process control and material handling. To address the immediate need for a coating system with easy application and rapid turnaround, Luna Innovations proposes to develop a coating system with extended pot life and controlled cure. The coating is applied using traditional techniques (roller, brush, sprayer) and once the coating is in place the cure can be triggered by an external stimulus. In this manner, the coating will behave like a rapid cure system (ready to recoat or use in 20 minutes) without the associated difficulties in material handling.BENEFITS: Significant time, money and manpower go into recoating ship surfaces during an overhaul. Areas that require multiple coats must have time for primer coats to dry before application of the stripe coat or top coat, and the top coat must dry before work can be done in that or adjacent areas. Existing polyurethane and polyurea rapid cure systems are available that reduce the cure time to less than 20 minutes, but they must be mixed at the spray head, require special equipment, and expose the applicator to dangerous isocyanates. The proposed system would allow for easy application by brush, roller, or traditional spray equipment due to an extended potlife, while still curing in less than 20 minutes when triggered by an external stimulus. The controlled cure would allow for rapid recoating or immediate use of the recoated area. The isocyanate-free system is also safer for the applicators, as well as all workers in the vicinity. The proposed coating system could be modified for different coating chemistries and is therefore applicable to many industries, both military and commercial.