Monolayer behaviors and LB films of dihydroxo (phthalocyaninato) silicon and its polymer - one-dimensional phthalocyaninato-polysiloxanes

A novel rigid-rod polymer, 2,9,16,23-tetra-tetradecanophthalocyaninato poly siloxane and its precursor dihydroxo(2,9,16 ,23-tetra-tetradecanophthalocya ninato) silicium were prepared. The monolayer behaviors of the compounds at the air-water interface are investigated by means of in situ Brewster angl e microscopy and their corresponding pi-A isotherms. The LB films of the co mpounds are deposited by a horizontal dipping technique and their structure s are characterized by electronic absorption spectra. Phase changes charact erized of the emergence of the network structure were observed during the c ompression/expansion cycles for both the compounds. The study revealed that the. polymer could form fairly homogeneous monolayers in which the marcroc ycle rings of the terminal of the polymer take a face-to-face arrangement b oth at the air-water interface and in LB films, as for the monomer, besides the main face-to-face arrangement, J-like arrangement of the marcrocycle r ing was observed. (C) 2000 Elsevier Science B.V. All rights reserved.