3-(8-Octenyl) thiophene was used for successful preparation of functionalized poly-(2-chloro-xylylene) (PCX) layers in the course of CVD process. The set of spectral methods used has allowed us to conclude that such modification is based on the chemical reaction of double bonds with xylylene radicals. Functionalized films were used for further chemical transformation in the course of polycondensation of 3-octylthiophene. Resulted samples are bilayer films and polythiophene layer is chemically connected with PCX one. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 1528-1531, 2011