Correlation of intermolecular interaction energy and properties of cross-linked polybiphenyloxidpyromellitimide

Deformation-toughness properties, thermal and form stability of polypyromellitimide films modified with bis-maleimides of various chemical composition in different quantities are investigated. Activation energies of thermooxidative destruction are estimated according to the data of temperature-toughness correlation in the solid state and on the basis of the data obtained by means of dynamic thermogravimetry in the liquid state. The values of the energy of intermolecular interactions in films are determined as their remainder. Linear correlations between the energy of intermolecular interactions and mechanical properties of polypyromellitimide films modified with bis-maleimides are established, which is of special importance for further understanding of the essence of the phenomena responsible for the formation of certain characteristics, as well as for obtaining of polyimide materials with given properties with minimum loss of time, material resources and labour. (C) 1999 Elsevier Science Ltd. All rights reserved.