Lipopolymers for surface functionalizations.: 1.: Synthesis and characterization of terminal functionalized poly(N-propionylethylenimine)s

By a direct combination of the fast initiation technique and a selective quantitative termination reaction, terminally functionalized poly(N-propionylethylenimine)s (PPEIs) were prepared by cationic living ring-opening polymerization of 2-ethyl-2-oxazoline in a one-pot multistep reaction. The chain ends of the linear hydrophilic polymers were functionalized with different lipophilic moieties (methyl-, n-hexadecyl- (C-16-), and 1,2-O-diooctadecyl-sn-glyceryl- ((C-18)(2)-)) and a monofunctional silane coupling group. Varying the length of the double functionalized hydrophilic PPEI chain (n = 10, 20), surface active amphiphilic lipopolymers of controlled hydrophilic lipophilic balance could be obtained in high overall yields. The spectroscopic, chromatographic, and mass spectrometric characterization confirmed that each reaction step was nearly quantitative and narrow molecular weight distributions (M-w/M-n = 1.07-1.24) of all polymers.