ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 4, pp. 480−484. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © O.G. Khelevina, A.S. Malyasova, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 4, pp. 488−492.
AND POLYMERIC MATERIALS
Cross-Linking of Borosiloxane Oligomers and Properties
of Materials with Vulcanized Borosiloxane Coating
O. G. Khelevina and A. S. Malyasova
Ivanovo State University of Chemical Technology, pr. Sheremet’evskii 7, Ivanovo, 153000 Russia
Received February 2, 2014
Abstract—Cross-linking of liquid borosiloxane oligomers was studied. The reaction is described by a ﬁ rst-order
rate equation for irreversible reactions. The effective cross-linking rate constants and activation energies of the
reaction were calculated. The properties of materials with the vulcanized borosiloxane coating were studied.
The physicomechanical properties of materials with borosiloxane coating are higher than those of materials with
coatings based on vulcanized liquid siloxane rubbers.
Materials based on liquid low-molecular-weight
siloxane rubbers are widely used in building, automobile
transport, electrical and radiotechnical industry, and
medicine, for treatment of textile materials to enhance
their crease resistance, to prolong their service life, and
to impart to them the wear resistance, for fabrication
of molds and molding materials, and in production of
rolled materials with vulcanized siloxane coating .
These materials exhibit decreased inﬂ ammability, high
water resistance, resistance to oil and benzine, and
maximal frost resistance (–70°С).
However, low-molecular-weight siloxane rubbers
exhibit low resistance to tear and wear, and the adhesion
of vulcanized siloxane coatings to synthetic fabrics is
low. Therefore, it is topical to develop new materials
based on oligoelementoorganosiloxanes, oligomers
whose backbones are built of silicon, oxygen, and
inorganic element atoms .
Borosiloxane oligomers are of interest as oligoele-
mentooorganosiloxanes. These compounds are capable
of cross-linking by polycondensation at elevated tem-
peratures without introducing other cross-linking agents
. Liquid borosiloxane oligomers can be prepared by
the reaction of low-molecular-weight liquid polysilox-
anediols with boric acid esters. In the process, boron
atoms are incorporated into the siloxane structure [2–5]:
According to , incorporation of boron into
the siloxane structure also occurs in reaction of
polysiloxanediols with boric acid:
Incorporation of boron into the siloxane structure
leads to considerable changes in the properties of the
vulcanized coatings. In particular, the wear resistance
of the coatings and the adhesion of vulcanized coatings
to various materials are enhanced. Also, the coatings
become considerably less rigid. Speciﬁ c properties of
borosiloxane elastomers are due to the formation of
supramolecular structures via coordination bonds of
boron atoms .