RU2001047C1 - Butyl acrylate-acrylonitrile-5-vinyltetrazole copolymer as synthetic adhesive for magnetic tape coatings - Google Patents

Description

where p - 70-55 wt.%

m -20-30 wt.%

K - 10-15 wt.% with a number average mole of m. 4000-120000.

Preservation of the absorption bands characteristic of each of the comonomers in the copolymer extracts carried out by different solvents confirms that a copolymer, rather than a mixture of homopolymers, was formed as a result of the reaction.

The content of the acid groups of the copolymer was determined by titration of the crushed films with alkali in dimethylformamide.

Example 1. A glass reactor equipped with a jacket for supplying coolant or heating is used for copolymerization. The sanded top cover has openings for a stirrer, a thermolar, a reflux condenser, outlets for supplying reaction components and a nitrogen blower. The copolymerization is carried out in an organic solvent at a temperature of 60-80 ° C under the action of radical type catalysts.

The order of loading the components is as follows.

The solvent, monomers, initiator are loaded into the reactor in a stream of nitrogen with stirring. Set the desired reaction time and temperature. To determine the characteristics of the copolymer, either a polymerizate is used, or part of the copolymer is precipitated from the reaction mixture with ethanol, charged with an antioxidant and dried to constant weight in a vacuum oven at a temperature of 60 ° C and a residual pressure of 10-20 mm Hg.

The recipe for polymerization, m.h. Butyl acrylate70}

Acrylonitrile201 100

5-Vinyltetrazole 10J

Ethyl acetate 150

Azoisobutyronitrile 1.0 Reaction temperature, ° С60 Duration of reaction, h 20 Conversion of monomers, May.% 99.8 Number average molecular weight 120,000 The content of acid groups.

wt.% 1,6

PRI me R 2. The order of loading and polymerization is analogous to example 1.

The recipe for polymerization, m.h. Butyl acrylate 551

Acrylonitrile 30 g 100

5-Vinyltetrazole 15

Butyl acetate100

Azoisobutyronitrile 1.0 Reaction temperature, ° С70

The duration of the reaction.h20

Conversion of monomers, wt.% 100 Number average molecular weight

weight100000

The content of acid groups, wt.% 2,4

PRI me R 3. The order of loading and polymerization is similar to Example 1.

The recipe for polymerization, m.h. Butyl acrylate 651

Acrylonitrile 20 100

5-Vinyltetrazole 15)

Methyl ethyl ketone 400

Porophore 4A4C, wt.% 3.0

Reaction temperature, ° С80 Reaction time, h18 Conversion of monomers, wt.% 99.8 Number average molecular weight 40,000 Content of acid groups, wt.% 2,4 EXAMPLE 4. The order of loading and polymerization is similar to Example 1 .

The recipe for polymerization, m.h. Butyl acrylate 60

Acrylonitrile 30 100

5-Vimiltetrazole 10J

Cyclohexanone 150

Azopentanol Ts1.0

Reaction temperature. ° C70 Duration of reaction, h 20 Conversion of monomers. wt.% 10.0 Srednekamennogo molecular weight 120,000 The content of acid groups, wt.% 2.8 EXAMPLE 5. The order of loading and polymerization is similar to Example 1.

The recipe for polymerization, m.h.

Butyl acrylate 60

Acrylonitrile 301 100

5-Vinyltetrazole 10J

Ethyl acetate / butyl acetate (60:40 vol.%) 150

Azoisobutyronitrile May%

1,0

Reaction temperature. ° C70 Duration of reaction, h18 Conversion of monomers, wt.% 100 Number average molecular weight 65000 Content of acid groups, wt.% 2.1 The use of the copolymer is illustrated by the following examples.

In order to obtain a polymer film forming the working layer of magnetic tapes and evaluate the quality of the binder polymer, the resulting composition (copolymer solution in a solvent of a given concentration) is mixed with a curing agent - hexamethoxymethylmelamine (GM-3 resin). To lower temperature and speed

0

5

curing, a dodecylbeneolsulfonic acid catalyst is used. The reaction mass is thoroughly mixed, held for 10 minutes to remove air bubbles, the films are cast and cured at a temperature of 120 ° C for 2 hours.

Polymeric films of binders must possess the necessary adhesive properties to a polyethylene terephthalate base, maximum cohesive strength, elasticity, hardness, and stability in extreme climatic conditions.

The test results are presented in the table.

(56) U.S. Patent No. 2889299, cl. 260-26.6, 1959.

US patent No. 2970079, CL. 162-164, 20 1961.

Physico-mechanical properties of polymer films

 ) Conditions for curing polymer films:

polymer, wt.% 100

hexamethoxymethylmelamine, wt.% 10.0

dodecylbenzenesulfonic acid, wt.% 1,0

temperature, ° С120

cure time, h2.0

) A copolymer of butyl acrylate, acrylonitrile and methacrylic acid is synthesized

according to US Pat. 2970079, USA 1961.) A soap-based copolymer of vinyl chloride and vinyl acetate in a composition with rubber

SKN-40.

Claims (1)

The claims Copolymer of butyl acrylate. ACRYLONITRIL AND 5-VINYL TETRAZOL AS A POLYMERIC BINDER FOR WORKING LAYERS OF MAGNETIC INFORMATION CARDS A copolymer of butyl acrylate, acrylonitrile and 5-vinyl tetrazole of the General formula where p-55 -70 wt.%; hl-20 -ZOMAS.%; M.t I AM , M.I I 1 "... .about "And HK-COIKTp (MGAMDOM CUMWIUM in GM 4 mind" DGD, f HUtfM X t T- vArrr / schvll. , -0, -C-) "AND {- sn - s -) {a - s -) cm 10 fifteen k-10-15% wt.%. with an average of a few mol.m. 40,000 to 120,000 as a polymer binder for the working layers of magnetic information carriers. "A T-