Aqua Resin, manufactured by the Aqua Resin Company, is a water-based resin that can be used in fiberglass applications. Several forms are available and one has fiberglass roving mixed in with the compound, called Aqua Glass. It is water-based, but once cured, it is impervious to water. Strength-wise, it is claimed to be stronger than conventional fiberglass
Water-based polyurethane (WBPU) can be substituted for epoxy resin in some applications. Hobbyist tutor PL Daniels recommends using WBPU as a resin instead of conventional epoxy resins for making cowlings for models. Little information is available on the structural integrity of WBPU, since this area has not been investigated extensively. For non-structural decorative components, however, it is adequate.
In 2005 engineering senior Rama Etekallapalli investigated bio-based polyurethane nanocomposites (BBPN). These composites, which are water-and-soybean based, are said to be competitive in integrity with traditional fiberglass. While this preliminary research is significant, much more research still needs to be done in comparison testing with conventional fiberglass epoxies.