Interfacial synthesis and properties of l-lysine-derived optically active poly(ester-imide)s

l-Lysine hydrochloride was transformed to ethyl l-lysine dihydrochloride. This salt was reacted with trimellitic anhydride to yield the corresponding diacid (1). Interfacial polycondensation results novel poly(ester-imide)s (PEIa–i). These polymers have inherent viscosities in the range of 0.23–0.47 dl g−1, display optical activity, and are readily soluble in polar aprotic solvents. They start to decompose (T10%) above 350 °C and display glass-transition temperatures at 100.42–172.81 °C. All of the above polymers were fully characterized by UV, FT-IR and 1H NMR spectroscopy, elemental analysis, TGA, DSC, inherent viscosity measurement and specific rotation.