1158 ISSN 1070-3632, Russian Journal of General Chemistry, 2007, Vol. 77, No. 7, pp. 1158 1163. Pleiades Publishing, Ltd., 2007. Original Russian Text I.V. Gofman, V.M. Svetlichnyi, V.E. Yudin, A.V. Dobrodumov, A.L. Didenko, I.V. Abalov, E.N. Korytkova, A.I. Egorov, V.V. Gusarov, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 7, pp. 1075 1080. Modification of Films of Heat-Resistant Polyimides by Adding Hydrosilicate and Carbon Nanoparticles of Various Geometries 1 I. V. Gofman a , V. M. Svetlichnyi a , V. E. Yudin a , A. V. Dobrodumov a , A. L. Didenko a , I. V. Abalov a , E. N. Korytkova b , A. I. Egorov c , and V. V. Gusarov b a Institute of Macromolecular Compounds, Russian Academy of Sciences, Bol’shoi pr. V.O. 31, St. Petersburg, 199004 Russia e-mail: gofman@mail.macro.ru b Institute of Silicate Chemistry, Russian Academy of Sciences, St. Petersburg, Russia c Belarussian State University of Transport, Gomel, Belarus Received November 9, 2006 Abstract The possibility of modifying the properties of poly(4,4 -oxydiphenylene)pyromellitimide films by introducing into prepolymer solutions nanoparticles of various compositions and structures [hydrosilicate nanoparticles in the form of layered structures (montmorillonite) and nanotubes; carbon nanofibers] was examined. New intercalating agents, tetranuclear aromatic diamines, were suggested for pretreatment of montmorillonite prior to introduction into heat-resistant polymers. The mechanical characteristics of the nanocomposites with hydrosilicate nanotubes can be optimized by chemical pretreatment of the nanotubes prior to introduction into the polymer matrix. Introduction of the above-named nanoparticles into the polymer matrix appreciably increases the elastic modulus of the material. The largest increase in the elastic modulus is observed with hydrosilicate nanotubes of the chrysotile structure, coated with an aromatic modifier. DOI: 10.1134/S1070363207070043 One of priority problems of the modern polymeric materials science is the development of novel highly heat-resistant film materials and improvement of the existing materials. These materials are necessary for many branches of the modern engineering such as aviation and aerospace engineering, ship building, electronics, instrument making, and some special fields of electrical engineering. Wide opportunities to solve this problem are of- fered by nanotechnological approaches, namely, by modification of the existing polymeric materials by introducing various nanoparticles into the polymer matrix. Numerous studies in which this approach is applied to modification of diverse polymeric materials have been published during the past decade. Among them are studies concerning the effect of introducing nanoparticles (mainly montmorillonite and carbon nanotubes) into aromatic polyimides [1 12]. 1 Reported at the Third All-Russia Conference Surface Chemistry and Nanotechnologies (St. Petersburg Khilovo, September 24 October 1, 2006). Interest in such polymeric materials is due to their unique set of properties [13]. They combine extremely high heat resistance (today aromatic polyimides are the most heat-resistant among polymeric materials commercially produced in the world), excellent dielec- tric properties, high mechanical characteristics, and high chemical and radiation resistance. That is why aromatic polyimides are much in demand by various branches of engineering, and development of new materials based on polymers of this class is an ex- tremely urgent problem. The range of nanoparticles of various compositions suitable (from the structural and morphological view- point) as modifiers for polyimide matrices considera- bly expanded recently, but the results of their intro- duction into polyimide matrices are poorly under- stood. Furthermore, the majority of papers concerning polyimide nanocomposites do not allow comparative evaluation of different types of nanoparticles as poly- imide modifiers. The goal of this study was to compare the perform- ance of various types of nanoparticles added into a polyimide matrix. To this end, a series of nanoparti-