Marine Grade Polyester Resins for Boat Building in the 1990s

Long-term evidence strongly supports the suitability of polyester resins for the construction of marine structures. However, misuse and incorrect selection has resulted in some distrust of their use for the manufacture of large structures. In this paper the issues surrounding the limitations of general purpose resins are discussed and cost-effective alternatives suggested which, if used correctly, can resist blister formation indefinitely. The mechanical performance of these systems is also discussed and compared with vinyl esters, epoxies and toughened resins. Under cold curing conditions isophthalic acid and isophthalic acid-neopentyl glycol based resins are more than adequate for resisting blister formation for, in some systems, in excess of 20 years at ambient temperatures and with laminate properties matching those of cold cured epoxy or vinyl ester systems. Examples are given of the effective combination of different resin systems where the main structural laminate is protected by an environmental barrier providing cost-effective structural composites suitable for all marine structures.