We report on the formation of stable and uniformly transferable Langmu
ir monolayers of a methacrylic homopolymer of Disperse Red-13 (HPDR13)
. There was no need of covalently attaching long alkyl side chains or
mixing the homopolymer with film forming materials. HPDR13 was derived
from DR13-methacrylate by a homo polymerization reaction in the prese
nce of 2,2'-azobisisobutyronitrile as initiator. Surface pressure isot
herms were obtained under various subphase temperatures, pH conditions
and at several compression speeds. The monolayer has also been charac
terized by surface potential isotherms. The results indicated that, in
contrast to the poor stability of a methacrylate-DR13 monomer monolay
er, stable monolayers of HPDR13 could be obtained at the air-water int
erface. A uniform layer by layer transfer has been demonstrated by the
linear increase of maximum absorption with increasing film thickness.
A red shift observed in the UV-Vis spectra of the Langmuir-Blodgett (
LB) films revealed a possible J-type aggregation of molecules. LB film
s have also been characterized by Fourier Transform infra Red (FTIR) s
pectroscopy. (C) 1998 Elsevier Science S.A. All rights reserved.