A method of producing the high molecular weight polycarbodiimide comprises the steps of providing an isocyanate component comprising toluene diisocyanate (TDI), a carbodiimidization catalyst, and a first solvent. The method further comprises the step of polymerizing the isocyanate component in the first solvent and in the presence of the carbodiimidization catalyst to produce a reaction mixture including at least one carbodiimide compound and the first solvent. In addition, the method comprises the step of combining a second solvent and the reaction mixture. Finally, the method comprises the step of polymerizing the at least one carbodiimide compound for a second period of time in the first and second solvents and in the presence of the carbodiimidization catalyst to produce the high molecular weight polycarbodiimide.
