SU402533A1 - METHOD OF OBTAINING THERMORACTIVE RESIN12 - Google Patents

Description

The invention relates to the field of obtaining thermosetting resins used as heat-resistant binders in electrical insulation technology.

A known method for producing thermosetting resins by the condensation of aromatic hydrocarbons and their derivatives with formaldehyde in an acidic medium when heated. However, these resins have insufficient adhesion and dielectric properties, as well as a reduced reactivity when heated.

The aim of the invention is to improve the adhesive and dielectric properties of the resin and increase its reactivity when heated. This is achieved by introducing into the reaction of condensation of aromatic compounds with formaldehyde, aromatic acids or aromatic amines in an amount of 0.25-1 mol per 1 mol of diphenol oxide. Formaldehyde is taken in the amount of 1.2-1.8 mol per 1 mol of defininyloxide.

Condensation is carried out at a temperature in an acidic medium. As aromatic compounds, compounds of tina diphenyloxide, m-xylene, naphthalene are used; as aromatic acids, salicylic and phenanthranilic acids; as aromatic amines - aniline, metaphenylenediamine.

Resin-based films (obtained by condensation of aromatic hydrocarbons, formaldehyde and aromatic acids or amines, have good dielectric properties 5 at 250 ° C:

p „101-1012 ohm-cm;

tgSiooo ,, 0.01-0.03;

6 2.5-3.

The temperature of the onset of decomposition of the resins according to thermo-data, obtained on a Kurnakov instrument, is in the region of 290-420 ° C. When heated, the resin is rapidly transferred to a non-meltable and insoluble state.

Example 1. Diphenyl oxide, salicylic acid and 1 paraform in a molar ratio of 1: 0.25: 1.2 are condensed at a temperature of 100 ° C for 6 hours in an acid mixture environment consisting of sulfuric and acetic acids in a volume ratio of 1: 9 . The reaction is carried out with an iB flask equipped with a reflux condenser and a stirrer. After silkworm and water washes, as well as vacuum drying the condensation product

25 (yield 70-90% of theory) is a resin soluble in organic solvents with a melting point of 90-95 ° C, acidic and hydroxyl numbers of 50-60 and 2-3, respectively, molecular weight. DK 1500.

The resin should be modified by self-hardening at a temperature of 200 ° C for 9–12 min and possesses good adhesion to metals.

Example 2. Condensation was carried out, as described in Example 1, but instead of salicylic acid B | Water a-nilip in the same amount. The reaction is carried out for 2 hours. The resulting resin has a melting point of 62-64 ° C; molecules pYY weight 1500-1600.

Example 3. Condensation was carried out as described in Example 1, but instead of dipheuil oxide, 1-xylene was introduced in the same amount. The resulting resin has a melting point of 85-90 ° C; It is soluble in organic solvents.

Example 4. Condensation is carried out as onisapo in TI 1 or 2, but instead of diphenyloxide is introduced on phthalip in the same amount. The resulting resin has a melting point of 95-UOS and is dissolved in organic solvents.

in the same quantity. The reaction is carried out for 2 hours.

Example 6. Condensation is carried out as described in Example 2, instead of aniline, 5 meta-phenylenediamine is introduced in the same amount.

From the point of view of the operational characteristics of the final products, the most preferred options for modifying aromatics-based polymers 0 aromatic acids and aromatic amines are (examples 1 and 2.

Invention

The method of thermal thermo-reaction of resin 5 by condensation of aromatic compounds selected from the group of diphenyloxide, m-xylene, naphthalene with formaldehyde, in an acidic environment with heating, characterized in that Aromatic compounds are introduced into the reaction.

Example 5: Conduct condensation as

described in (Example 1, but instead of salicylic 25, a general formula of the acid, phenanthropyl acid is introduced

where X is NH2, is OH;

g / -NH2, - COOH, -I;

and the components will take in molar ratios of 1: 1.2-1-1.8: 0.25-1, respectively.