RU2495069C1 - Polymer composition for absorbing high-frequency energy - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to radioelectronic engineering, particularly to producing polymer compositions for absorbing high-frequency energy in microwave devices, e.g. in amplifiers of compensation channels of radar stations. The polymer composition for absorbing high-frequency energy contains a polymer - low-molecular weight dimethylsiloxane synthetic rubber SKTN, a cold curing catalyst No68 and absorbent filler - pigment aluminium powder.

EFFECT: invention provides improved absorption properties with low thickness of the absorbent layer in a wide temperature range and high humidity.

2 tbl, 3 ex

Description

The invention relates to electronic equipment, in particular to the production of polymer compositions designed to absorb high-frequency energy in microwave devices, for example, in amplifiers of compensation channels of radar stations.

A known polymer composition for absorbing high-frequency energy [RF patent 2294347 C1, published 02.27.2007], including synthetic rubber, low molecular weight dimethylsiloxane SKTN, absorbing filler powder alsifer fraction of not more than 63 microns and a cold curing catalyst No. 68, in the following ratio, wt.h .:

Synthetic rubber, low molecular weight dimethylsiloxane SKTN 15-25 Alsifer fraction powder no more than 63 microns 75-85 No. 68 Cold Curing Catalyst 0.6-1.0

The disadvantage of this composition is the complex technology for the manufacture of alsifer powder and low absorption properties with a small thickness of the absorbing layer.

The closest in technical essence to the proposed polymer composition for absorbing high-frequency radiation is [RF patent 2349615 C1, published March 20, 2009] polymer composition for absorbing high-frequency energy, containing synthetic rubber, low molecular weight dimethylsiloxane SKTN, cold curing catalyst No. 68, as well as absorbing filler iron carbonyl radio engineering, in the following ratio of components, parts by weight:

Synthetic rubber, low molecular weight dimethylsiloxane SKTN 15-25 Iron carbonyl radio engineering brand R-10 78-83 No. 68 Cold Curing Catalyst 0.6-1.0

The disadvantage of the prototype is the high density and low absorption properties with a small thickness of the absorbing layer.

The technical result of the invention is to obtain a polymer composition with high absorbing properties with a small thickness of the applied absorbing layer in a wide temperature range and high humidity, which is important for on-board equipment of aircraft.

The essence of the invention lies in the fact that the proposed polymer composition for absorbing high-frequency energy contains a polymer - synthetic rubber low molecular weight dimethylsiloxane SKTN (TU 2294-002-00152000-96) and a cold curing catalyst No. 68 (OST 38.03239-81), as well as an absorbent filler.

New in the proposed solution is that the polymer composition for absorbing high-frequency energy as an absorbing filler contains aluminum pigment powder (GOST 5494-71) in the following ratio of components, parts by weight:

Synthetic rubber, low molecular weight dimethylsiloxane SKTN (TU 2294-002-00152000-96) 15-25 No. 68 Cold Curing Catalyst (OST 38.03239-81) 0.5-1.2 Pigment aluminum powder (GOST 5494-71) 12-20

A polymer composition for absorbing high-frequency energy is made by simply mixing the components and curing them at room temperature.

Table 1 shows the compositions of the proposed composition for the absorption of high-frequency energy.

Table 1 No pp Components Example 1 Example 2 Example 3 one Synthetic rubber, low molecular weight fifteen twenty 25 dimethylsiloxane SKTN 2 No. 68 Cold Curing Catalyst 0.5 0.85 1,2 3 Powder aluminum pigment 12 16 twenty

The specified range of components was chosen due to the fact that with a decrease in the amount of aluminum powder, the required microwave energy absorption efficiency is not achieved, and with an increase, the composition is not technologically advanced (viscous, heterogeneous) and cannot be applied with a thin layer.

With an increase in the number of cold curing catalyst No. 68, the viability of the composition decreases, and due to the rapid increase in viscosity it is impossible to obtain a thin uniform film of the composition.

With a decrease in the amount of cold curing catalyst No. 68, complete absorption of the absorbent composition does not occur.

Table 2 shows the results of comparative tests of the analogue and the claimed polymer composition for absorbing high-frequency energy deposited on the microwave signal amplifier.

table 2 №№ pp Indicators Prototype (patent 2349615) Example 1 Example 2 Example 3 one Microwave signal attenuation in the frequency range 8-12 GHz, dB: - at a temperature of + 25 ° C 5 13 fifteen eighteen - at a temperature of -60 ° C 5 eighteen 16 17 - at a temperature of + 200 ° C 3 13 fifteen fourteen After exposure high humidity four fourteen 13 fifteen 98% at a temperature of + 40 ° C for 12 days 2 Density, g / cm ³ 4.45 1.55 1,60 1,52 3 Thickness applied 1,0 0.45 0.50 0.60 absorbent coating four Weight loss no > 5 times > 5 times > 5 times

As can be seen from the data shown in table 2, the proposed polymer composition for absorbing high-frequency energy has several advantages:

- the efficiency of absorption of microwave energy with a small thickness of the absorbing layer ("13-18 dB" versus "5 dB" with a thickness of less than 1 mm);

- radio characteristics are maintained in a wide temperature range (from -60 ° C to 200 ° C) and exposure to high humidity;

- lower density ("1.5-1.6 g / cm ³ " versus "4.45 g / cm ³ "), which is important for on-board equipment of aircraft.

- weight reduction of the proposed composition compared with the prototype more than 5 times.

Claims (1)

A polymer composition for absorbing high-frequency energy, containing polymer - synthetic rubber, low molecular weight dimethylsiloxane SKTN, cold curing catalyst No. 68, as well as an absorbing filler, characterized in that it contains aluminum pigment powder as the absorbing filler in the following ratio, wt.h .:
Polymer - synthetic low molecular weight rubber dimethylsiloxane SKTN 15-25 No. 68 Cold Curing Catalyst 0.5-1.2 Powder aluminum pigment 12-20