Synthesis and Radical Polymerization Behavior of Methacrylamides Having L-Leucyl-L-alanine Oligopeptide Moieties. Effect of the Peptide Chain Length on the Radical Polymerizability

Synthesis and radical polymerization of methacrylamides having l-leucyl-L-alanine oligopeptide moieties, N-methacryloyl-(L-leucul-L-alanine) n methyl ester (MA-'LA)n-M, n = 2 4), were carried out. The monomers were synthesized by the condensation of (L-leucul-L-alanine) 1-3 methyl ester . trifluoroacetate with N-methacryloyl-L-leucyl-Lalanine using 1-ethyl-3(3-Di-methylaminopropyl) carbodiimide hydrochloride or N'N-dicyclohexyl-carbodiimide as coupling reagents. The radical polymerization was carried out in 1,1,1,3,3,3-hexafluoro-2-propanol using e,2'-azoisobutyronitrile as an initiator at 60°C. The monomer with a longer peptide chain showed a smaller conversation and degree of polymerization.