Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 7, pp. 1270−1280.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
B.A. Zaitsev, I.D. Shvabskaya, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 7, pp. 1164−1174.
AND POLYMERIC MATERIALS
Mechanism of Formation, Structure, and Properties
of Heat-Resistant Network Polymers Prepared
by Thermal Curing of Rolivsans
B. A. Zaitsev and I. D. Shvabskaya
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
Received April 29, 2010
Abstract—The mechanism of structural transformation of divinylaromatic formulations containing methacrylates
of secondary aromatic alcohols and diols into heat-resistant and strong glassy network polymers was examined.
The structure and properties of the products were studied. The Rolivsans prepared demonstrate the possibility
of chemical construction of high-temperature thermosets in which molecules with thermally stable ether groups
and labile ester groups, providing excellent process properties of the formulation in the low-temperature step of
the reactive forming, are capable of transforming into heat-resistant network polymers.
Improvement of the processability and of the
technological, environmental, adhesion, and mechanical
properties, enhancement of the crack resistance and
chemical stability, and reduction of the porosity of heat-
resistant organic polymers are still topical problems. The
known high-temperature thermosetting resins, as a rule,
exhibit low solubility, high melting point, and high
viscosity of the solution or melt. They are characterized
by the release of toxic volatiles and by considerable
shrinkage in processing. The resulting heat-resistant
materials are frequently brittle and exhibit micro- and
macroporosity, low resistance to alkalis, and insufﬁ cient
hydrolytic stability [1–4].
Thermosetting polyfunctional resins termed
Rolivsans allow some of the above drawbacks typical
of the known heat-resistant polymers to be mitigated or
even eliminated. They are used for preparing insulating
casting and impregnating compounds, polymeric and
composite materials, ﬁ ber glasses, carbon-reinforced
plastics, adhesives, and coatings. Materials based on
cured Rolivsans exhibit high resistance to thermal
oxidation (up to 315°С) and to the most aggressive
, HF, NaOH). They are intended for
extreme operation conditions in various branches of
modern engineering [5–9].
It was found previously that Rolivsans, which are
low-viscosity formulations (500–3500 mPa s), mainly
consist of monomeric aromatic ethers [4,4'-CH
(М3)] and of products of dimerization and trimerization
of М1 and М2, oligoethers (OL) with terminal
methacrylate groups (30 ± 15 wt %) [10, 11]:
The viscous liquid state determining excellent
processing characteristics of Rolivsans is due to their
peculiar chemical structure: The component molecules
consist of ether (diphenyl oxide groups) and ester
(methacrylate) moieties characterized by low potential
barrier to internal rotation of bonds. However, factors
responsible for the high heat resistance of cured Rolivsans
remain to be elucidated, because the known analogs,