1070-4272/05/7801-0159C2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 1, 2005, pp. 159!165. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 1,
2005, pp. 161!167.
Original Russian Text Copyright + 2005 by Men’shikova, Shabsel’s, Evseeva, Shevchenko, Bilibin.
AND POLYMERIC MATERIALS
Synthesis of Carboxylated Monodisperse Latexes
and Their Self-Organization in Thin Films
A. Yu. Men’shikova, B. M. Shabsel’s, T. G. Evseeva,
N. N. Shevchenko, and A. Yu. Bilibin
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
St. Petersburg State University, St. Petersburg, Russia
Received July 15, 2004
Abstract-The capability of carboxylated latexes of poly(methyl methacrylate) and copolymers of styrene
with glycidyl methacrylate or methacrylic acid for self-organization in thin films was studied in relation to the
compositions of the dispersion medium and polymer and to the latex particle size.
Monodisperse polymer particles of submicrometer
size can serve as basis for formation of photonic crys-
tals (PCs), a new class of dielectric materials promis-
ing both for experimental and theoretical studies of
nonlinear optical effects and for development of new
devices for quantum electronics and telecommunica-
tions industry . In the PC lattice, the dielectric
permittivity modulates with a period of the order of
the light wavelength. This fact accounts for the exis-
tence of the photonic band gap (PBG), an energy
range in which the light propagation inside the crystal
is suppressed . Of particular interest are three-
dimensional (3D) photonic crystals in which a high
density of structural components can be attained.
Composites based on synthetic opals with a fcc
lattice formed by close-packed submicrometer spheres
of amorphous silica are considered as promising mate-
rials for obtaining the required photonic-crystal prop-
erties . However, obtaining a perfect 3D lattice
with these materials involves serious technological
problems. The high density of SiO
results in particle
sedimentation, giving rise to stresses and defects in
the ordered structure. As a result, synthetic opals have
a polydomain structure with a domain size of 303
100 mm. Furthermore, the surface nonuniformity of
microspheres formed by aggregation
of nanometer-sized particles results in considerably
increased diffuse scattering of electromagnetic waves
at the phase boundary and in suppressed photonic-
crystal effects . Methods of polymer chemistry
allow preparation of monodisperse surface-uniform
submicrometer-sized particles of a lower density com-
pared to inorganic materials . Development of
3D ordered structures based on polymer particles of
various diameters and compositions would allow their
optical properties (primarily the PBG position and
width) to be varied in a wide range.
To reveal factors that act in the step of self-organi-
zation of the primary polymer matrix and affect the
structure and optical characteristics of the forming
PCs, it seems appropriate to study systematically how
the structure of the polymer and the size and surface
properties of the polymer particles affect their capabil-
ity for formation of highly ordered 3D structures.
For this purpose, we studied various kinds of latexes
based on poly(methyl methacrylate) (PMMA) and
copolymers of styrene with methacrylic acid (PSt3
MAA) or glycidyl methacrylate (PSt3GMA).
To ensure monodisperse composition and stability
of latexes, their polymer base was modified in the
course of the synthesis with carboxy groups; their
ionization imparts a surface charge to the particles.
By varying the composition of the dispersion medium,
it is possible to control this charge and hence the
forces of electrostatic repulsion between the latex
particles, and thus to optimize the conditions of for-
mation of the ordered structures.
Styrene (St) and dimethylformamide (DMF) were
purified by distillation, following standard procedures.
Glycidyl methacrylate (GMA), methacrylic acid
(MAA, pure grade), and K
, NaOH, HCl, and
(chemically pure and analytically pure
grade) were used without additional purification.
The purification procedures and characteristics of