DE1181419B - Process for the production of crosslinkable copolymers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C08f

German class: 39 c -25/01

Number: 1181419

File number: C 28236IV d / 39 c

Filing date: October 20, 1962

Opening day: November 12, 1964

It is already known that this leads to crosslinkable polymers or copolymers It is possible that crosslinkable monomers are used or included to build them up. As such crosslinkable monomers are z. B. N-methylolacrylamide and its ether used together with other non-crosslinkable monomers. Those produced in aqueous emulsion Polymers cleave when heated, possibly in the presence of catalysts and in one of less than 7 lying pH range, formaldehyde, whereby crosslinking takes place. During this process, however, occur at the same time considerable shrinkage, so that ζ. B. with such polymers or copolymers Produced coatings on drying with crosslinking result in films with strong Stress cracks are streaked.

It has now been found that crosslinkable copolymers of butyl acrylate together with styrene or acrylonitrile in an aqueous medium in the presence of catalysts, optionally with the addition of emulsifying agents, in the presence of methacrylamide derivatives are obtained if the alkali metal salt of methacrylamidomethylene sulfonic acid is used as the methacrylamide derivative. Such copolymers are already crosslinked when heated to about 95 ^° C., even in a pH range above 7, with elimination of sulfuric acid, and in the process produce shrink-free films or coatings.

This result is surprising after corresponding, with the use of alkali salts known copolymers produced from acrylamidomethylene sulfonic acid are very difficult to crosslink are.

In contrast to the ethers of N-methylolacrylamide, the alkali metal salts of methacrylamide methylene sulfonic acid used in the process according to the invention are easily accessible. They are obtained in known manner in the reaction of N-methylolmethacrylamide with Alkalipyrosulfiten at about 50 to 6O ⁰ C in an aqueous solution, being able to be used for the latter readily copolymerization.

Compared to the polymers, the N-MethylolacryT-amid or contain its ether as a crosslinking component, show that according to the method of the invention available copolymers a greater stability of the emulsions, so that it is not necessary is to always keep the pH of the emulsions above 7 in order to prevent premature crosslinking.

The interpolymers which can be prepared according to the invention can be used for many purposes, for example processes for the preparation of
crosslinkable copolymers

Applicant:

Cassella Farbwerke Mainkur Aktiengesellschaft, Frankfurt / M.-Fechenheim

Named as inventor:
Dr. Wilhelm Kunze,
Frankfurt / M.-Fechenheim

z. B. for the impregnation or coating of textiles, of products made of fiber materials or Leather and for coating wood or metal. Through the networking during the drying process are z. B. with textiles against laundry and dry cleaning resistant finishes or coatings obtain.

example 1

The mixture is mixed in succession with stirring in a nitrogen atmosphere

340 ecm of water (made air-free with nitrogen), 7 g of alkyl sulfonate,
Ig triethanolamine,
35 g butyl acrylate,
12 g styrene,

23 g of a 30% strength aqueous solution of methacrylamidomethylene sulfonic acid Sodium.

At 50 ° C., the following solutions are added dropwise over the course of one hour, with the dropping of solutions 3 and 4 is only started after 20 minutes:

1. 0.8 g of ammonium persulphate in 30 ecm of water,

2. 1.0 g of sodium pyrosulfite in 30 ecm of water,

3. a mixture of 70 g of butyl acrylate and 24 g of styrene,

4. 46 g of a 30% solution of methacrylamido

sodium methylene sulfate.

After the addition has ended, the mixture is stirred for a further 4 hours

at 55 ° C. Is obtained as a 26% ig ^e dispersion of a copolymer of 65% butyl acrylate, 22.5% styrene and 12.5% methacrylamidomethylensulfosaurem sodium.

409 727/496

3 4

When the dispersion dries, a solution of methacrylamidomethylene sulfonic acid Na-

colorless film which shows no shrinkage cracks. trium dropped in.

and in dimethylformamide or trichlorethylene only after the addition has ended, the mixture is stirred for a further 4 hours

somewhat swellable, but not soluble. The disperser at 55 ° C. A 26% dispersion is obtained in this way

sion is therefore suitable for. B. very good for impregnating 5 a copolymer of 52% butyl acrylate,

of fabrics, with a trichlorethylene and washing 35% acrylonitrile and 13% methacrylamidomethylene

stable finish is obtained. Sodium sulfonic acid.

When drying the dispersion without additives

Example 2 ^{eme ne} ^ ^e film formed, which no shrinkage cracks

ίο has. This is in dimethylformamide and trichloro

Ethylenes swell only slightly with one another in a nitrogen atmosphere.

mixes: _n ,

Claims (1)

Claim: 340 ecm of air-free water,,. ,. ", Process for the production of crosslinkable 7 g of alkyl sulfonate, ₁ g of copolymers by polymerizing 30 g of butyl acrylate, butyl acrylate together with styrene or 20 g of acrylonitrile, acrylonitrile in an aqueous medium in the presence 25 g of a 30% solution of methacrylamido catalysts, optionally with addition sodium methylene sulfate. ^of emulsifying agents, in the presence of 2o methacrylamide derivatives, characterized by At 50 ° C, with stirring in 1 hour, the draws that the methacrylamide derivative Solutions of 0.8 g of ammonium persulfate in 30 ecm of the alkali metal salt of methacrylamidomethylene sulfonic acid Water and 1.0 g of sodium pyrosulfite in 30 ecm is used.
Water and about 20 minutes after the start 40 minutes the mixture of 60 g of butyl acrylate. ester and 40 g of acrylonitrile and 50 g of a 30% USA patent specification No. 2,718,515. 409 727/496 11. 64 © Bundesdruckerei Berlin