FT-IR SPECTROSCOPIC INVESTIGATIONS OF PHOTOCHEMICAL GRAFTING OF AMPHIPHILES ONTO POLYACRYLONITRILE SURFACES

The photoreactive amphiphile p-(stearyl amido) benzoyl azide (SABAz) was synthesized and grafted onto surface of thin polyacrylonitrile (PAN) films by irradiation with UV light. Two different techniques were applied, namely, Langmuir-Blodgett (LB) deposition and casting from solution. A high degree of order and a hydrophobic surface were established by reflection-absorption FT-IR spectroscopy (RA-IR) and contact angle measurements. The stability against treatment with water, tetrahydrofuran, and chloroform was tested. A considerable amount of amphiphilic molecules remains on the surface also after treatment with chloroform. RA-IR spectra taken from photomodified PAN films prepared by both techniques are almost identical after chloroform treatment, indicating a similar coupling mechanism. (C) 1995 John Wiley & Sons, Inc.