SU1753497A1 - Carbonyl iron base metal-polymer absorbing material - Google Patents

Abstract

The invention relates to the manufacture of high-frequency energy absorbers for electronic instrumentation and communications equipment. The essence of the invention: the proposed metal-polymer absorbing material has the following composition, wt.%: ED-20 epoxy-resin 7.7-11, polyoxypropyleneamine hardener 5.3-7.3; carbonyl iron. 1 tab.

Description

The invention relates to metal-polymeric absorbing materials (MPM) based on carbonyl iron and is intended for the manufacture of absorbers of high-frequency energy of electronic instrumentation, communications equipment and other public goods, in particular in the manufacture of hybrid integrated microwave modules.

Known MMM, containing a mixture of powders of carbonyl iron, a melt of ferrite, quartz filler and epoxy resin.

This MPM has high mechanical strength and provides the possibility of machining it.

The disadvantages of this MMM should include a relatively narrow range of operating frequencies, a rather high cost and laboriousness in manufacturing.

The closest in technical essence to the proposed is MMM (ferroepoxide) based on carbonyl iron and polymer base in the following ratio of components, wt.%:

Compound K-11523,4

Hardener polyethylene-polyamine (PEPA) 3,5

Carbonyl Iron Else This MPM has the required adhesive ability and is convenient for applying devices and devices operating in the microwave range to the Metal surfaces.

A disadvantage of the known MPM is a low absorption capacity, of the order of 7 dB / mm, mainly due to the use as a polymeric binder material which is not capable of binding a sufficient amount of carbonyl iron. The disadvantages of MMM include low elasticity and low heat resistance. The operating temperature range is from -60 to 80 ° C, which limits the possibility of its use, for example, in hybrid integrated microwave modules that require sealing by soldering at temperatures above 80 ° C.

The aim of the invention is to increase the absorption capacity, elasticity and heat resistance.

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The goal is achieved by the fact that the metal-absorbing carbonyl iron-based absorbent material containing the polymer base and the hardener contains ED-20 epoxy resin as the polymer base, and the polyoxypropyleneamine hardener as the hardener in the following ratio, wt.%: Resin epoxy dianova ED-207,9-11

Polyoxypropylene-amine hardener5.3-7.3

Carbonyl ironErest

To conduct an experimental verification of the proposed composition, various mixtures of ingredients were prepared, three of which show optimal results (see table).

The technology of preparing MLM and applying it to the protected surface includes the following operations. For example, 8.62 g of epoxy resin ED-20, 5 3 g of polyoxypropyleneamine hardener and 85.6 g of carbonyl iron, previously dried in a thermostat at 110-120 ° C, are charged to a tumbler of a mechanical mixer for 2-2.5 hours and sifted through a vibrating screen. The mixture is homogenized using a mechanical stirrer. Stirring is started at low speed of the mixer, gradually increasing the speed of the mixer by the end of homogenization. The total mixing time is 15 minutes. Next, the liquid composition is poured into the mold or directly onto the surface of the product to be protected. Full polymerization of MPM occurs within 8 hours at 60 ° C or within 6 hours at "0 ° C."

As a result of preliminary examination of mining, it was established that the use of a polyoxypropyleneamine hardener in the amount of 7.3 May. % or less allows to obtain an elastic material with an absorbing capacity of 12.6 dB / mm in the centimeter wavelength range with a frequency of 9180 MHz (composition 1). Using a hardener in the amount of 5.8 wt.% (Composition 2) increases the absorption capacity of MMM to 14 dB / mm, however, reduces elasticity. A decrease in the hardener in an amount of up to 5.3 wt.% (Composition 3} with a slight increase in absorption capacity (up to 14.2 dB / mm) reduces the elasticity of MMM. A further decrease in hardener makes the liquid composition difficult to process, poorly mixed, heterogeneous, poorly pouring or on the surface of the product to be protected. In addition, the table shows that the proposed MPM provides a high absorption capacity of at least 12.6 dB / mm, which is 1.8 times greater than that of the known MPM.

The proposed material, moreover, simultaneously provides a wider range of operating temperatures from -60 to 150 ° C, i.e. The upper limit of the working range is almost 2 times higher than that of the known MPM and, therefore, the heat resistance is higher. The proposed MMM provides and

greater elasticity. It is characterized by a relative elongation of from 110 to 118%. At the same time, the known MMMs are not elastic.

In addition, the proposed MPM provides high adhesion strength to metals and metallic coatings, for example tin bismuth, which also expands its field of application. In addition, simplicity of manufacture and low cost, since

It does not contain scarce and expensive materials.

The absorptive capacity of the proposed material has the highest value of 14.2 dB / mm, which is the greatest

among the known ones.

Claims (1)

Claims Metal-polymer absorbing material based on carbonyl iron, containing polymer base and A hardener, characterized in that, in order to increase the absorption capacity, elasticity and heat resistance, it contains epoxy resin D-20 as a polymer base, and polyoxypropyleneamine hardener as a hardener in the following ratio of components, wt.%: Epoxy-Dianova ED-207,9-11 resin Polyoxypropyleneamine hardener5, 3-7.3 Carbonyl ironErest