FLUORINATED POLY(ALPHA, L-GLUTAMATE)S

Poly(alpha,L-glutamate)s carrying C-8, C-10, and C-12 fluorinated side chains were synthesized by polymerization of the corresponding amino acid N-carboxyanhydrides. Contact angle measurements with water were u sed to assess the effects of fluorination on the surface energies of f ilms of the resulting polypeptides. The wettability of the polymers wa s found to decrease with increasing fluorine content, as expected. A r emarkably high contact angle (121 degrees) was measured for the homopo lymer carrying C-12 fluorinated side chains, indicating a surface cons isting of closely packed trifluoromethyl groups. Side chain crystalliz ation, consistent with the formation of such a surface, was suggested by the results of X-ray diffraction and calorimetric measurements.