1070-4272/01/7403-0473$25.00C2001 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 74, No. 3, 2001, pp. 473! 477. Translated from Zhurnal Prikladnoi Khimii, Vol. 74, No. 3,
2001, pp. 463!467.
Original Russian Text Copyright + 2001 by Salimgareeva, Prochukhan, Sannikova, Kuvatov.
AND POLYMERIC MATERIALS
Properties of Crystalline Polyvinylenes Prepared
by Phase-Transfer Dehydrochlorination
of Vinyl Chloride Copolymers
V. N. Salimgareeva, Yu. A. Prochukhan, N. S. Sannikova, and Z. Kh. Kuvatov
Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences,
Ufa, Bashkortostan, Russia
Received January 10, 2000; in final form, June 2000
Abstract-Crystalline polyvinylenes were prepared by phase-transfer dehydrochlorination of binary
copolymer of vinyl chloride with vinyl acetate (9 : 1 molar ratio) and ternary copolymer with vinyl acetate
and vinyl alcohol (27 : 1 : 2 molar ratio), and the chemical and electrical properties of these substances and
of products of their thermolysis were studied.
Polymers with a system of conjugated bonds in the
main chain, including polyvinylenes, are of particular
interest due to their semiconductor, paramagnetic, and
other properties, which are not typical of common
macromolecular compounds. The variety of specific
properties is due to the features of their electronic
structure and conformation of conjugated molecules.
These properties depend on the polymer structure; and
the presence of the crystalline phase in the polymer
increases the electrical conductivity and decreases the
concentration of paramagnetic centers as compared
with the amorphous sample . The crystalline struc-
ture provides high anisotropy of the polymer proper-
ties, necessary for application in microelectronics.
The properties of crystalline polyvinylenes formed
by acetylene polymerization using Ziegler3Natta
catalysts are described in detail (e.g., [2, 3]). A meth-
od for preparing highly crystalline polyvinylene by
dehydrochlorination of polyvinyl chloride under the
conditions of phase-transfer catalysis was developed
in . The resulting polyvinylene exhibits unique
chemical and physical properties. It is highly stable
with respect to oxidants and is easily dehydrogenated
at high temperatures . The products of its thermoly-
sis exhibit high strain sensitivity  and paramagnetic
Crystalline polyvinylenes were also prepared by
phase-transfer dehydrochlorination of a binary copoly-
mer of vinyl chloride with vinyl acetate and a ternary
copolymer with vinyl acetate and vinyl alcohol .
Some properties of these polyvinylenes were studied
in this work.
In our work we studied crystalline polyvinylenes
prepared by phase-transfer dehydrochlorination of
commercial samples of a binary copolymer of vinyl
chloride with vinyl acetate (9 : 1 molar ratio) and a
ternary copolymer of vinyl chloride with vinyl acetate
and vinyl alcohol (27 : 1 : 2 molar ratio) in aqueous
solutions of potassium hydroxide in the presence of
phase-transfer catalysts .
The properties of crystalline polyvinylenes were
compared with those of amorphous samples prepared
from the same vinyl chloride copolymers  and of
crystalline polyvinylenes prepared from polyvinyl
chloride (PVC) . The products of conversion of
vinyl chloride homo- and copolymers are coarse black
or dark brown powders (0.831.0 mm particle size).
The polymer structure was studied using polariza-
tion-optical microscopy. The polyvinylene crystals
prepared from copolymers are significantly smaller
than those prepared from polyvinyl chloride and larger
than the crystals obtained by acetylene polymeriza-
tion: the crystal size is 132 , 10 10
, and (235)0
mm , respectively.
The thermal treatment of the samples at 1003
1200oC was carried out in a quartz tube in a vacuum
mm Hg); at higher temperatures a ceramic tube
was used. The sample was heated with a heating rate
of 1.5 deg min
and kept at chosen temperature for
2 h. All manipulations were performed under argon.
The specific electrical resistivity was measured by
the four-probe procedure in cells equipped with stain-