Polymeric blends having improved flame retardance properties and good ductility at low temperatures are disclosed. The blend is formed from (A) a photoactive additive containing a photoactive group derived from a monofunctional benzophenone; and (B) a polymer resin which is different from the photoactive additive. The additive can be a compound, oligomer, or polymer. When exposed to ultraviolet light, crosslinking will occur between the photoactive additive and the polymer resin, enhancing the chemical resistance and flame retardance while maintaining ductility.