A comparative study of chain conformation at the surface of poly(β-benzyl-L-aspartate) and poly(γ-benzyl-L-glutamate) films with high resolution electron energy loss spectroscopy.

High resolution electron energy loss spectroscopy (HREELS) is used to study spin-coated films of two polyaminoacids, poly(β-benzyl-L-aspartate) (PBA) and poly(γ-benzyl-L-glutamate) (PBG). The experimental results show that the side chains of these two polymers take a very different conformation at the surface: This is confirmed by infrared spectroscopy (ir) and differential scanning calorimetry (DSC) which are more bulk sensitive techniques. This effect is further attributed by computer graphics facilities (BIOSYM) to a larger flexibility of the side chain of PBG as compared to PBA. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]