AND POLYMERIC MATERIALS
Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 3, pp. 417−425.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © L.N. Andreeva, S.V. Bushin, M.A. Bezrukova, T.N. Nekrasova, R.T. Imanbaev, V.D. Pautov, O.V. Nazarova, Yu.I. Zolotova,
E.F. Panarin, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 3, pp. 445−453.
Conformation Properties of Poly(N,N-dimethylaminoethyl
Methacrylate) Macromolecules in Various Solvents
L. N. Andreeva, S. V. Bushin, M. A. Bezrukova, T. N. Nekrasova, R. T. Imanbaev,
V. D. Pautov, O. V. Nazarova, Yu. I. Zolotova, and E. F. Panarin
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
Received January 23, 2012
Abstract—Poly(N,N-dimethylaminoethyl methacrylate) macromolecules in the un-ionized and ionized states
were studied by methods of molecular hydrodynamics, optics, and polarized luminescence. The conformation,
relaxation, and optical parameters of the macromolecules were determined. The Mark–Kuhn–Houwink equations
were obtained for the intrinsic viscosity and diffusion and sedimentation coefﬁ cients.
(PDMAEM) attracts researchers’ attention for a long
time. It exhibits antimicrobial and fungicidal properties;
it is one of the most effective polymers for the DNA
transport; it is also used as flocculant in mining in-
dustry [1–7]. PDMAEM is a weak base. Its temperature-
sensitive properties and conformation of macromolecules
are determined by the nature of the solvent (pH, ionic
strength, kind of counteranions) [8–14]. Signiﬁ cant role
is also played by the molecular weight and architecture
of PDMAEM macromolecules .
Determination of the molecular weights and dimen-
sions of macromolecules of amphiphilic polymers and
polyelectrolytes still involves problems because of the
occurrence of intra- and intermolecular interactions.
This particularly concerns polyelectrolytes, because
they are characterized by two oppositely acting factors:
hydrophobic interaction and Coulomb repulsion. The ﬁ rst
factor leads to enhancement of intra- and intermolecular
interactions which decrease the hydrodynamic volume,
whereas the electrostatic forces tend to increase the vol-
ume of polymeric coils, i.e., the hydrodynamic volume.
Salt additions can shield the polyelectrolytic effect but
enhance the hydrophobic intramolecular interactions.
Hydrophobic contacts can be broken by adding organic
solvents or surfactants.
In this study we determined the molecular, conforma-
tion, optical, and relaxation properties of PDMAEM in
the forms of the base and salt in dilute solutions. To this
end, we used the methods of molecular hydrodynamics
(sedimentation, diffusion, viscometry) and optics (ﬂ ow
birefringence, polarized luminescence).
PDMAEM was prepared by free-radical polymeriza-
tion of DMAEM in benzene, toluene, or isopropanol
solution at 60°С with azobis(isobutyronitrile) (AIBN)
as initiator or in aqueous solution at 25°С with a 1 : 1
mixture of (NH
enediamine as initiator (Table 1).
The polymer with a luminescence label was prepared
by free-radical copolymerization of DMAEM with 9-an-
thrylmethylmethacrylamide; the concentration of the
monomers in the isopropanol solution was 15 wt %, and
the AIBN concentration, 1.5 wt % relative to the mono-
mers. The content of luminescence labels in the polymer
did not exceed 0.2 mol %.
The intrinsic viscosities were measured by the stan-
dard procedure in the Ostwald capillary viscometer. For