Aspartic acid, N,N-(methylenedi-4,1-cyclohexanediyl) bis-, tetraethyl ester (CAS # 136210-30-5). The subject product is called Aspartic acid, N,N-(methylenedi-4,1-cyclohexanediyl) bis-, tetraethyl ester (CAS # 136210-30-5). It is an aromatic amino acid ester. It is also known as diethyl 2-[[4-[[4-[(1,4-diethoxy-1 4-dioxobutan-2-yl) amino]cyclohexyl]methyl]cyclohexyl]amino] butanedioate, and Desmophen LS 2973. You describe it as a “specific non-polymerized chemical” which is used to make the polyaspartic urethane coatings.
[1] Please importantly note that only the relevant portion of the related is displayed above. You may refer to the said customs ruling for the entire ruling explanation.
[1]. https://rulings.cbp.gov/ruling/N312448