THE POLYMER-CERAMIC MATERIAL FOR THE MANUFACTURE OF GAS DISCHARGE CHAMBER FOR THE ELECTRIC ROCKET ENGINE

This study discusses the creation of heat-resistant dielectric composite material based on organosilicon polymers for the manufacture of gas discharge chamber (GDC) for the electric rocket engine (ERE). A binder has been proposed that meets the high requirements for vibration resistance and electromagnetic permeability of GDC in the megahertz range of electromagnetic waves. Based on this binder filled with silicon nitride powder, GRС was designed; this product was fully tested as part of laboratory 200 kW ERE. The research of structural transformations that occur during heating of materials was carried out by synchronous thermal analysis. The material obtained in the result of the experiment, the basis of which was SiSiB®PVMQ filled with Si3N4 60% by mass, is characterized by a number of properties that are structured and described in this study. As a result of the study, it was demonstrated that the studied material is characterized by heat resistance up to 400 ºС. On the basis of these materials, the authors produced a GDC, which was tested as part of a laboratory model. It was established that the increase in mass loss over 400 °C is due to the initiation of the process of thermal degradation of the main polymer chain.

Synthesis, Characterization, and Electrical Properties of Poly(azophenyleneazo-2,4-diamino-1,5-phenylenes)

Poly(azophenyleneazo-2,4-diamino-1,5-phenylenes) were synthesized via diazotization of m- and p-phenylenediamine and azocoupling with m-phenylenediamine. It is found that, simultaneously, dihydrobenztriazolic units were formed as a result of cyclization reaction between amino and azo groups located in ortho position to each other. Oxidation of poly(azo-p-phenyleneazo-2,4-diamino-1,5-phenylene) was carried out and new polymer with benzotriazolic units in the main polymer chain was obtained. The conductivities of obtained polymers doped with iodine were increased with doping levels increase from 10−9–5 × 10−8 S/m to 0,1–0,6 S/m.