The present invention provides a reaction product having polyether carbamate groups formed from (A) polyoxyalkylene amine, and (B) cyclic carbonate, in an equivalents ratio ranging from 1:0.5 to 1:1.5. Further provided is a process for preparing the aforementioned reaction product. The present invention also is directed to an improved curable coating composition including (1) a reactive functional group-containing polymer, and (2) a curing agent having functional groups reactive with the functional groups of (1), the improvement being the inclusion in the coating composition the reaction product. Multilayer composite coatings including a first coating layer formed from the curable coating composition and a second coating layer over the curable coating composition are also provided, as well as coated substrates.