Alternating co-polymers of cyclic dicarboxylic acids and cyclic diamines may be used to produce nylon 6,6. Di-substituted furan compounds may be used as the raw material for producing furan-dicarboxylic acids and/or furan-diamines. The furan-dicarboxylic acids and furan-diamines may be copolymerized to produce polymer precursors for nylon 6,6. The polymer precursors may be hydrogenated and/or deoxygenated to produce nylon 6,6.