ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 8, pp. 1306!1311. + Pleiades Publishing, Inc., 2006.
Original Russian Text + M.I. Abdullin, T.V. Gainullina, O.S. Kukovinets, A.R. Khalimov, N.N. Sigaeva, R.R. Muslukhov, M.A. Kayumova, 2006,
published in Zhurnal Prikladnoi Khimii, 2006, Vol. 79, No. 8, pp. 1320!1325.
AND POLYMERIC MATERIALS
Synthesis and Properties of Epoxy Derivatives
of Syndiotactic 1,2-Polybutadiene
M. I. Abdullin, T. V. Gainullina, O. S. Kukovinets, A. R. Khalimov,
N. N. Sigaeva, R. R. Muslukhov, and M. A. Kayumova
Bashkir State University, Ufa, Bashkortostan, Russia
Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, Ufa, Bashkortostan, Russia
Received November 25, 2005; in final form, March 2006
Abstract-Samples of modified 1,2-polybutadiene were prepared by the reaction of the polymer with per-
acetic acid or tert-butyl hydroperoxide in the presence of a catalyst, hexacarbonylmolybdenum. The hydro-
dynamic characteristics of dilute solutions and the rheological properties of concentrated solutions of the start-
ing and epoxidized polydiene in hydrocarbon solvents were studied. The Huggins constant K
, second virial
, root-mean-square size of macromolecular coils (
, and the enthalpy, entropy, and Gibbs
energy of activation of the viscous flow of solutions of the starting and modified polydiene were estimated.
According to published data, addition to polymeric
formulations of polydienes, including 1,2-polybutadi-
ene (1,2-PB), that contain a small amount of epoxy
units in the backbone and pendant chains improves
the properties of the compounds and expands the field
of their application . In particular, 1,2-PB con-
taining 538% oxirane oxygen is used for preparing
compounds with enhanced flame resistance and im-
proved sealing properties  and as a component of
paint-and-varnish materials  and of compounds
whose rigidity does not change with time and the
elasticity and high adhesive power are preserved under
moist conditions .
Here we suggest a new approach to the synthesis of
epoxy derivatives of syndiotactic 1,2-PB, allowing
introduction of a prescribed amount of epoxy groups
into the polydiene macromolecules.
As starting polymer we chose syndiotactic 1,2-PB
with a Mooney viscosity of 30. The polymer had
the following characteristics: flow point T
glass transition point T
= 315oC, M
= 71.6 0 10
= 1.8 (M
were determined by
GPC), degree of crystallinity 30%, content of 1,2 and
1,4 units 84 and 16%, respectively.
Epoxidation of syndiotactic 1,2-PB was performed
in benzene; the epoxidizing agent was peracetic acid
prepared in situ by the treatment of solution acetic
acid with a concentrated H
. The thus synthesized
epoxy derivatives of syndiotactic 1,2-PB were char-
H (300 MHz) and
C (75.47 MHz)
NMR spectroscopy. The degree of modification of
1,2-polydiene was determined by comparing its NMR
spectra with those of the starting polymer .
The signals were assigned using the COSY H3H and
COSY C3H2D correlation spectroscopy.
The formation of epoxy groups in the macromol-
ecules of syndiotactic 1,2-PB was confirmed by
the presence of weak doublets at 55.89 and 55.65 ppm
C spectra and of an unresolved group of
signals at 2.732.9 ppm in the
H spectra, with
the chemical shifts typical of epoxy groups .
C triplets at 27.57, 27.43, and
27.35 ppm and doublets at 127.83130.3 ppm, corre-
sponding to the C atoms in the cis units formed by
1,4 polymerization, decreased in intensity relative to
the starting polydiene.
The experimental results show that the epoxidation
of syndiotactic 1,2-PB with peracetic acid mainly
involves the >C=C< double bonds in the 1,4-cis units
of the backbone. This is apparently due to a higher
nucleophilicity of these bonds compared to those in
the 1,2 units . The NMR spectra of modified syn-
diotactic 1,2-PB are consistent with the relatively low
degree of epoxidation of the polymer upon its treat-