FIELD: aircraft technology.
SUBSTANCE: invention relates to gas-filled polymers (foams) based on polyetherimides (PEI), which are used inside aircraft. A method for obtaining PEI foam from foamed particles is claimed to include the processing of a mixtureб wt. %: PEI 80-99.5, foaming agent 0.5-10 and additives 0-10 on an extruder with a perforated plate into a foamed granulate, then the mixture from the extruder is directed to a granulator for underwater granulation, and later the energy necessary for pre-foaming is supplied by radiation heating with infrared or microwave radiation and the foamed granulate is then subjected to further foaming to obtain foam from foamed particles. The temperatures between the loading zone and the end of the screw are 180-380°C. The temperature of the perforated plate is 250-350°C. The melt temperature at the exit through the perforated plate is 230-360°C. The granulator for underwater granulation is designed to work with such a combination of temperature and pressure at which foaming is prevented. Foamed PEI has a glass transition temperature of 180-215°C and cells with an average diameter from 40.6 mcm to 2 mm. A method including the processing of the mixture is also claimed, wt. %: PEI 90-100 and additives 0-10 on an extruder with a perforated plate into a foamed granulate, a foaming agent is then added to the granulate in an autoclave in such an amount that then its content in the granulate is 0.5-10, wt. %, and after that, the granulate containing the foaming agent is foamed by pressure relief and/or by heating to a temperature of 150-230°C to obtain foam from foamed particles. A method for manufacturing a combined part by gluing, stitching or welding foam from foamed particles with cover materials is claimed. A method for manufacturing a combined part is claimed, including a foam made of foamed particles, which is foamed in the presence of a coating material in such a way that it connects to the foam by gluing or welding with it.
EFFECT: development of temperature–resistant, difficult-to-ignite (fire-resistant) foams for use in the aviation industry.
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