RU2285706C1 - Polymeric composition - Google Patents

Abstract

FIELD: chemistry of polymers.

SUBSTANCE: invention describes a polymeric composition based on synthetic low-molecular dimethylsiloxane rubber SKTN of sort A, cold hardening catalyst № 68 that comprises additionally epoxide diane resin ED-20, amine hardening agent AF-2 representing a product of interaction of phenol, formaldehyde and ethylenediamine, organic solvents chosen from mixture of xylene and ethyl alcohol in the ratio = 2:1 in the following ratio of components, mas. p. p.: epoxide diane resin ED-20 (All-Union State Standard, AUSS) 10587-84, 90-110; synthetic low-molecular dimethylsiloxane rubber of sort A, AUSS 13835-73, 90-110; hardening agent AF-2 as a product of interaction of phenol, formaldehyde and ethylenediamine, specify 2494-511-00203521, 9-11; cold hardening catalyst № 68, OST 38.03239-81, 2.5-3.5; organic solvent as a mixture of xylene, AUSS 9410, and ethyl alcohol, AUSS 18300 taken in the ratio = 2:1, 10-20.

EFFECT: valuable properties of composition.

2 tbl, 3 ex

Description

The invention relates to the field of production of polymer compositions intended for fastening electro-radio elements, wires, bundles to printed circuit boards, etc.

Glue VK-9, mastic LN, U-9M, etc. [OST 107.460 007 009-02 “Adhesives for products of radio electronic equipment and means of communication” are known in modern technology for additional fastening of electro-radio elements.] They have an insufficient operating temperature range from -60 up to + 125 ° C. VK-9 glue is hard, replacement of electro-radio elements if necessary without their destruction is impossible.

Despite the wide range of operating temperatures from -60 to + 200 ° С, adhesive-sealant Elastosil 137-83 based on organosilicon resin cannot be used where application on inclined, curved and vertical surfaces is required, i.e. does not have thixotropy. Also known is EDAF adhesive [OST 4G 0054210-83], consisting of epoxy diane resin ED-16, ED-20, amine hardener AF-2, the product of the interaction of phenol, formaldehyde and ethylene diamine and quartz, but it has a small operating temperature range from - 60 to + 85 ° С, hard, mechanically strong and its use does not allow replacing parts without their destruction.

Closest to the proposed polymer composition is a compound PK-68 [TU 38.103508-81] of the following composition in parts by weight: synthetic rubber, low molecular weight dimethylsiloxane SKTN grade A GOST 13835-73 - 100, catalyst No. 68 for cold curing - OST 38.03239-81 - 3-5.

However, this compound has low mechanical strength and lack of adhesive ability. This allows the removal of electro-radio elements if necessary without destroying them, but it does not provide operability under conditions of vibration from 2 to 10q in the frequency range from 10 to 2000 Hz. The PK-68 compound has low thixotropy, i.e. when applied, it does not hold on inclined, vertical surfaces, does not retain its shape and size, drains when applied to radioelements, low viability (30 minutes).

The technical task of the invention is the creation of a polymer composition for attaching electro-radio elements, wires, bundles to printed circuit boards, ensuring the operability of products under vibration from 2 to 10q in the frequency range from 10 to 2000 Hz, an increase in mechanical strength and adhesion with the possibility of replacing electro-radio elements without destruction, increased thixotropy, increased vitality.

The solution to the problem is achieved due to the fact that the polymer composition based on rubber of synthetic low molecular weight dimethylsiloxane SKTN grade A, cold curing catalyst No. 68, which is an organosilicon amine in an organic solvent, is characterized in that it additionally contains ED-20 epoxy diane resin, AF amine hardener -2 - the product of the interaction of phenol, formaldehyde and ethylene diamine, organic solvents from a mixture of xylene and ethyl alcohol in a ratio of 2: 1 in the following ratio components, pbw .: bisphenol epoxy resin ED-20 GOST 10587-84 - 90-110; synthetic rubber low molecular weight dimethylsiloxane grade A GOST 13835-73 - 90-110; hardener AF-2 is a product of the interaction of phenol, formaldehyde and ethylene diamine TU 2494-511-00203 521 - 9-11; cold curing catalyst No. 68 OST 38.03239-81 - 2.5-3.5; organic solvent - a mixture of xylene GOST 9410 and ethyl alcohol GOST 18300 in a ratio of 2: 1 - 10-20.

The proposed polymer composition is obtained by mixing and curing.

Table 1 shows the compositions of the compositions according to the invention, in table 2 their properties

Table 1 Formulations of the composition of the invention No. p / p Components Note 1 Note 2 Note 3 one. Epoxy Dianovy resin ED-20 GOST 10587-84 90 one hundred 110 2. Synthetic rubber
low molecular weight dimethylsiloxane SKTN grade A GOST 13835-73 90 one hundred 110 3. Hardener AF-2 is a product of the interaction of phenol, formaldehyde and ethylene diamine TU 2494-511-00203521 9 10 eleven four. Cold cure catalyst
No. 68 OST 38.03239-81 2,5 3 3,5 5. Organic solvent mixture of xylene GOST 9410 and ethyl alcohol GOST 18300 in a ratio of 2: 1 10 fifteen twenty

The specified range of components was chosen due to the fact that with a decrease and increase in the rubber content of low molecular weight dimethylsiloxane SKTN grade A, uncured porous sticky mixtures are formed. With a decrease in the amount of catalyst No. 68 and hardener AF-2, the composition does not cure, and with an increase, the viability of the composition decreases. A decrease in the amount of solvent reduces the viability of the polymer composition, and an increase leads to the formation of a porous structure and an increase in curing time. The proposed polymer composition ensured the operability of products under conditions of vibration from 2 to 10q in the frequency range from 10 to 2000 Hz due to an increase in mechanical strength and adhesive ability with the possibility of replacing electro-radio elements without their destruction, increasing thixotropy and viability.

table 2 Properties of the analogue and polymer composition according to the invention No. p / p Indicators Analogue Note 1 Note 2 Note 3 one The mechanical tensile strength, kPa (kgf / cm ² ) 196 (2) 430 (4) 430 (4) 430 (4) 2. Exposure to vibration from 2 to 10q in the frequency range from 10 to 2000 Hz exfoliating. exposure exposure exposure 3. Adhesive ability does not possess possesses possesses possesses four. Thixotropy no possesses possesses possesses 5. Vitality, h 0.5 > 1 > 1 > 1

As can be seen from table 2, the proposed polymer composition for attaching electrical elements of wires, bundles to printed circuit boards has several advantages:

- an increase in mechanical strength [430 (4) kPa (kgf / cm ² ) versus 196 (2)], while maintaining the ability to replace electrical radio elements without destroying them;

- ensures the operability of products under conditions of vibration from 2 to 10q in the frequency range from 10 to 2000 Hz ("withstand" against "peeling");

- adhesive ability ("possesses" against "does not possess") ;,

- thixotropy (“possesses” versus “absence”);

- greater viability (> 1 hour versus 30 minutes).

Claims (1)

A polymer composition for attaching electric radio elements of wires, bundles to printed circuit boards, and including synthetic low molecular weight dimethylsiloxane SKTN grade A rubber, cold curing catalyst No. 68, characterized in that it additionally contains ED-20 epoxy diane resin, AF-2 amine hardener - an interaction product , formaldehyde and ethylene diamine, an organic solvent from a mixture of xylene and ethyl alcohol in a ratio of 2: 1 in the following ratio of components, parts by weight: Epoxy Dianova Resin ED-20 90-110 Synthetic rubber, low molecular weight dimethylsiloxane SKTN-A 90-110 Hardener AF-2 is a product of the interaction of phenol, formaldehyde and ethylenediamine 9-11 No. 68 Cold Curing Catalyst 2.5-3.5 Xylene Organic Solvent and ethyl alcohol in a ratio of 2: 1 10-20