Carboxy acrylics are intended to meet the new demands of automotive industry
Several types of acrylic resins have been introduced since the mid 1980s. Capable of producing powders that are highly weatherable, they are intended to meet the new demands of the automotive industry.
Carboxy acrylics/TGIC combinations never really showed significant weatherability improvements over carboxy polyester TGIC systems,and the general concern about the use of TGIC has just about killed off this chemistry.
Carboxy acrylic / HAA combinations ,which have recently been promoted ,offer another possibility for this class of resin. Some studies have been conducted using carboxy acrylics in combination with bisphenol-A epoxies. These create super hybrids that have all te advantages of regular epoxy polyester hybrids but offer much higher chemical resistance. Such systems need to be acid catalyzed, which creates problems similar to those discussed in the section on the hydroxy polyester/TMMGU chemistry. The acid catalyzed carboxy acrylic /bisphenol-A epoxy combinations that were evaluated a few years ago had a tendency to yellow at higher cure temperatures.