New aliphatic poly(ester-carbonate)s bearing amino groups based on t-Butyloxy carbonyl as Protecting Group

Amino-functionalized six-membered cyclic carbonate tert-butyl(2-oxo-1,3-dioxan-5-yl) carbamate (TBC) was synthesized with tert-Butyloxycarbonyl (Boc) as protected group. Due to its thermal properties, ring-opening polymerization (ROP) carried out in a relatively low temperature, and Sn (Oct) 2 as catalyst. A series of copolymers were prepared with L-lactide (LA), ε-Caprolactone (CL) as co-monomers, searching for proper components and ratios. The protecting Boc-group was easy to remove by using trifluoroacetic acid (TFA). The structures of TBC and copolymers were confirmed by 1 H NMR and 13 C NMR analysis. Copolymers were characterized by DSC, GPC and water contact angle analysis. The introduction of pendant amino groups resulted in a significant enhancement of hydrophilicity of the copolymers.