DE2012810A1 - Cross-linked polyoxazolines for lacquers adhesives - and moulding compns - Google Patents

Abstract

High-mol., cross-linked substances with recurring -CONH-CHR2-CHR3-OCO units are produced by crosslinking polymers of oxazoline(s) of gen. formula: (in which R and R1 are H, 1 - 7C alkyl, 6 - 10C aryl; R2 and R3 are H or 1 - 3C alkyl) and opt. other copolymerisable monomers with di- and polycarboxylic acids by heating to ca. 100 - 300 degrees C. These polymers can be used for lacquers, coatings, adhesives, compression and other moulds compns. They are resistant to solvents, weathering, chemicals and esp. detergent solns. and also have good mechanical and dielectric properties.

Description

Crosslinked Polymers Containing Oxazoline Rings The invention relates to crosslinked polymers containing oxazoline rings and a process for their productionO It is known to use monooxazolines with anhydrides of aliphatic monocarboxylic acids to be heated at reflux temperatures, then treated with water to reduce Ring opening of the oxazolines to give the corresponding O-acylated carboxamides arrive (see U.S. Patent 2,410,318).

It is also known, for example 2-phenyloxazoline with p-nitrobenzoic acid to convert to the corresponding ß-benzamidoethyl p-nitrobenzoate by heating (cf. Journal of Organic Chemistry, Volume 15, 1950, pages 802-806).

It has also already been proposed to use monos and bis (oxazoline) with cyclic Dicarboxylic anhydrides, such as maleic anhydride, copolymers of maleic anhydride and copolymerizable vinyl monomers to resinous, cyclic, optionally networked imido parents (cf.

U.S. Patents 2,543,601; 2,543,602; 2,547,542; 2,547,495 to 498).

In addition, it is known to use oxazolines, which are in the 4- and 5-position, i.e. on the total of the carbon atoms adjacent to the nitrogen or oxygen at least 2 hydroxyl groups bound via a hydrocarbon residue contain over the hydroxyl groups with polycarboxylic acids with one mole weight under 350 to implement with heating. The carbon atom in the 2-position preferably bears the remainder of a drying or semi-drying carboxylic acid (val. USA patent 3,438,943).

After all, it is from the publication of Tsutomu Kagiya and Collaborator in "Journal Polymer Science" Volume 4, pages 257-260 (1966) known, linear polyester amides by polyaddition of adipic acid to bis-oxazolines in dimethylformamide to produce with ring opening of the oxazoline ring.

Even with reaction times of 10 hours and reaction temperatures from 1200 C, however, only yields of 24-61,96 of uncrosslinked polyesteramides are obtained obtain.

The object of the present invention was to provide oxazoline rings containing To convert polymers into high molecular weight, crosslinked substances.

The object was achieved in that polymers containing oxazoline rings are crosslinked by carboxyl groups.

It can contain the carboxyl groups in the oxazoline rings Be incorporated polymer, or in the absence of carboxyl groups in the polymer the crosslinking of the polymers can be achieved by products containing two or more carboxyl groups have per molecule.

The invention thus provides a process for the production of high molecular weight, crosslinked substances with recurring units of the formula I - CONH - CHR2 - CHR3 - OCO - 1, characterized in that polymers of at least one oxazoline of the formula ii wherein R and R1 denote hydrogen, alkyl with 1-7 carbon atoms, aryl with 6-10 carbon atoms, R2 and R3 denote hydrogen or alkyl with 1-3 carbon atoms, and optionally at least one further copolymerizable monomer with di- or Polycarboxylic acids can be crosslinked by heating to temperatures of approx. 100 - 3000 C.

In formula I and II, R, R1, R2 and R3 are preferably hydrogen and methyl. The following azolines may be mentioned by name, for example: 2-vinyl2-oxazoline, 2-isopropenyl- A 2-oxazoline, 0'- and ß-phenyl-2-vinyl- 4 2-oxazoline, 4-methyl-2-vinyl- CI 2-oxazoline, 2-isopropenyl-4-ethyli \ 2-oxazoline, 2-vinyl-5-methyl- iS 2-oxazoline, 2-vinyl-4,5-dimethyl A 2-oxazoline.

The carboxyl groups that act as crosslinkers can also already be present in the polymer, d. H. Monomers of the formula II, carboxylic acid groups containing monomers and optionally further monomers are copolymerized.

This then gives self-crosslinkable copolymers.

The term polymer in this application is homo- and Copolymers understood. The monomer units in the copolymers can be irregular distributed or contained in blocks. In some cases, for example with copolymers from maleic acid and vinyloxazolines, can the modules also alternate be arranged. Copolymers are also to be understood as meaning graft polymers, d. H. Monomers are grafted onto a preformed polymer.

The polymers to be used according to the invention are produced according to known methods, e.g. B. in bulk, solution, emulsion or dispersion (see. "Methods of organic chemistry, Houben-Weyl, Volume 14 / I, 4th edition, 1961).

As copolymerizable monomers - mixtures of these can also be used Monomers are used - are for example: a), ß-unsaturated Carboxylic acids with 3 - 5 carbon atoms, such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, Maleic acid half-esters with 1 - 18 carbon atoms in the alcohol residue, crotonic acid, itaconic acid etc.; b) Esters of unsaturated carboxylic acids with 3 - 5 carbon atoms and saturated aliphatic or cycloaliphatic alcohols with 1-20 carbon atoms, in particular Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, 2-Ethylhexyl (meth) acrylate, etc. The designation (meth) in those named Compounds means that the acrylates or methacrylates can be used.

c) Hydroxyalkyl and aminoalkyl esters of meth or acrylic acid, for example ß-hydroxyethyl (meth) acrylate, ß-hydroxypropyl (meth) acrylate, 2-aminoethyl (meth) acrylate hydrochloride; Hydroxybutyl (meth) acrylate, further monomers containing OH groups, such as hydroxymethylnorbornene, Allyl or vinyl ethers of polyols with 2 - 8 carbon atoms.

d) Aliphatic vinyl compounds, such as vinyl esters, vinyl ethers, vinyl ketones, z. B. vinyl chloride, vinyl acetate, vinyl propionate, chlorovinylacetate, vinyl ethyl ether, Vinyl methyl ketone, vinyl ethyl ketone, etc. Also vinylidene chloride.

e) vinyl aromatics, such as styrene, methyl styrene; Nuclear-substituted by C1 - C4 Styrenes, styrenes substituted by chlorine, vinyl heterocycles, such as 2-vinylpyrrolidone, 2-vinyl pyridine, etc .; f) α-monoolefins with 2 - 6 carbon atoms, such as ethylene, propylene, Butenes, hexenes; g) Conjugated diolefins with 4 - 6 carbon atoms, such as butadiene, isoprene, Dimethylbutadiene, 2-chlorobutadiene; h) nitriles and amides of α, ß-unsaturated Carboxylic acids with 3 - 5 carbon atoms, such as (meth) acrylamide, (meth) acrylonitrile, etc., N-substituted (Meth) acrylamides, such as N-methylol acrylamide or N-methylol methyl ether of (meth) acrylamide.

The monomers can be copolymerized in any ratio. Provided Monomers containing carboxylic acid groups with the vinyl oxazolines and optionally further monomers are copolymerized, it is advisable not to use more than 30 % By weight, based on total monomers, preferably 0.3-15% by weight, of carboxyl groups to use containing monomers.

The self-crosslinkable copolymers contain copolymerized units of 99.7-1.0% by weight, preferably 1-30% by weight, of at least one oxazoline of the formula in which R and R1 are hydrogen, alkyl having 1-7 carbon atoms, aryl having 6-10 carbon atoms, R2 and R3 are hydrogen or alkyl having 1-3 carbon atoms, 0.3-3o% by weight, preferably 0.3-15% by weight, at least one &, ß-unsaturated carboxylic acid with 3-5 carbon atoms and 0-98.7% by weight, preferably 45-98.7% by weight, of at least one further copolymerizable monomer The sum of the percentages by weight is always 100. The polymerization catalysts are inorganic per compounds such as potassium or ammonium persulfate, hydrogen peroxide, percarbonates such as dicyclohexyl peroxydicarbonate, persulfonates such as cyclohexylsulfonyl peracetate, organic peroxide compounds such as acyl peroxides, for example benzoyl peroxide, alkyl hydroperoxides, for example benzoyl peroxides, alkyl hydroperoxides. -Butyl hydroperoxide, cumene hydroperoxide, p-methane hydroperoxide, dialkyl peroxides such as di-tert-butyl peroxide, peroxyesters such as tert-butyl perbenzoate, azo compounds which form free radicals such as azodiisobutyronitrile. The inorganic or organic per-compounds are advantageously used in combination with reducing agents in a known manner. Suitable reducing agents are, for example, sodium pyrosulfite or bisulfite, sodium formaldehyde sulfoxylate, triethanolamine, tetraethylene pentamine.

The amount of catalyst to be considered is within the usual range limits applicable to polymerizations, d. H. between 0.01 and 5% by weight, based on the total amount of monomers.

To influence the molecular weight, the usual regulators, such as long-chain alkyl mercaptans, diisopropyl xanthate, nitro compounds or organic halogen compounds are used in the polymerization.

The polymerization temperatures depend on those used Monomer types and the activation systems and are between 0 and 1500 C, preferably between 40 and 800 C.

Homo- or copolymerization in solution can be carried out in all solvents be carried out in which the monomer compounds and the polymers are soluble are. Suitable solvents for this are alcohols with 1 - 8 carbon atoms, such as methanol, Isopropanol, butanol, 2-ethylhexanol, acetone, methyl ethyl ketone, "toluene, dimethylformamide, Chloroform, dioxane, methylene chloride, esters such as ethyl acetate, butyl acetate, etc., also Glycol monomethyl ether, glycol monobutyl ether, glycol monobutyl ether acetate.

The homopolymerization of the vinyl oxazolines or the copolymerization the vinyloxazoline with other monomers can also be carried out in aqueous suspension, the monomer mixture in water, which contains a suspension stabilizer, such as polymethyl vinyl ether, Polyvinylpyrrolidone, polyvinyl alcohol, Methyl cellulose, calcium phosphate, contains, suspended and then in a manner known per se after the addition of radical formers is polymerized.

Another embodiment is aqueous copolymerization Emulsion. The procedure here is such that either the entire amount of the monomers is polymerized all at once or only part of the monomer mixture is initially charged and the remainder is metered in after the reaction has occurred.

Both anionic and cationic or nonionic or combinations of these emulsifiers can be used.

Suitable anionic emulsifiers can be higher fatty acids, resin acids, acidic fatty alcohol sulfuric acid esters, higher alkyl sulfonates and alkyl aryl sulfonates, sulfonated castor oil, sulfonic succinic acid ester or the water-soluble salts of sulfonated ethylene oxide adducts can be used.

Examples of cationic emulsifiers are salts of quaternary ammonium or pyridinium compounds.

The known reaction products are used as nonionic emulsifiers of ethylene oxide with long-chain fatty alcohols or phenols, in particular Reaction products of more than 10 moles of ethylene oxide with 1 mole of fatty alcohol or phenol come into use.

The total amount of the above emulsifiers can be between 0.5 and 20% by weight, based on the total amount of monomers. It is preferably between 2 and 10% by weight.

If the copolymers contain oxazoline rings and carboxyl groups, see above the networking takes place in substance, z. B. as a powder or in solution or dispersion by heating to 100-3000C, preferably 110-1800C.

If the copolymers contain no carboxyl groups or become homopolymers the polymerizable oxazolines are used, the crosslinking takes place by addition of substances containing carboxyl groups.

As starting materials containing carboxyl groups for the inventive Processes are polymers containing carboxyl groups, polyaddition and polycondensation products with an average molecular weight of at least 600 and an acid number of at least 10 usable. They have at least two carboxyl groups.

Suitable polycondensation products containing carboxyl groups are, for example, polyesters made from aliphatic and / or aromatic polycarboxylic acids, such as adipic acid, succinic acid, maleic acid, phthalic acid, isophthalic acid, terephthalic acid, Hexahydrophthalic acid, methylhexahydrophthalic acid, trimellitic acid, pyromellitic acid and polyalcohols, such as ethylene and propylene glycol, butanediol-193, Butanediol-1,4, hexanediol, diethylene glycol, tripropylene glycol, glycerine, trimethylolpropane and their reaction products with alkylene oxides.

Polyesters from hydroxypivalic acid, thioglycolic acid, S-hydroxydecanoic acid, caprolactone and propiolactone, also with aliphatic and aromatic polycarboxylic acids containing modified hydroxyl groups and Alkyd resins containing carboxyl groups.

The preparation of the above-mentioned carboxylic acid groups containing Polycondensation products are carried out according to known processes, such as those for example in 11Methods of Organic Chemistry "Houben Weyl, 4th Edition, 1961, Volume 14 / II are described.

The polycondensation products containing carboxyl groups have Acid numbers of at least 10.

Suitable polyadducts containing carboxyl groups are white n likewise by known methods, as indicated above, by polyaddition of alkylene oxides, such as ethylene, propylene, butylene, phenoxypropylene oxide or from the bis-2,3-epoxypropyl ether of bisphenol A with polyols such as ethylene glycol, propylene glycol, 1,5-butanediol, 1,4-butanediol, hexanediols, glycerine, trimethylolpropane, pentaerythritol, Mannitol or sorbitol obtained with subsequent reaction with polycarboxylic acid anhydrides, being based on the moles of the polyol with n-hydroxyl groups obtained by polyaddition n-moles of a polycarboxylic acid anhydride are used.

Also polybutylene glycol (containing 2 terminal hydroxyl groups), obtained by anionic polymerization of tetrahydrofuran can, as above described, be reacted with 2 moles of polycarboxylic anhydride. As a polycarboxylic acid component are the same as those listed for the polyesters. The carboxyl groups polyadducts containing acid numbers of at least 10.

Next are carboxyl group-containing polymerization products for the method according to the invention suitable. Like the aforementioned polycondensation and polyadducts, they should also have an average molecular weight of over 600 exhibit -and at least 0.3% by weight, based on total monomers, of a carboxyl group-containing monomer incorporated. Such products homo- or copolymers of acrylic acid, methacrylic acid, crotonic acid, Be maleic acid, cinnamic acid, etc. Examples of comonomers are vinyl monomers, such as (meth) acrylic acid esters with 1 - 8 carbon atoms in the alcohol component, styrene, methystyrene, Oy-methylstyrene., Halogen-substituted styrenes, vinyl acetate, vinyl propionate, vinyl chloride, Vinylidene chloride, vinyl ethyl ether, vinyl butyl ether, N-vinylpyrrolidone, acrylonitrile, ethylene, propylene, but also conjugated diolefins such as butadiene, isoprene or chloroprene suitable.

Copolymers of acrylic and methacrylic acid are preferably used at least one monomer from the group (meth) acrylic acid ester with 1 - 8 carbon atoms in the alcohol component, (meth) acrylonitrile, styrene, butadiene, vinyl acetate, vinyl chloride or ethylene used, the content of built-in acrylic or methacrylic acid at least 0.3 wt .-% The preparation of the carboxyl group-containing homo- and copolymers are carried out by known methods, such as those in 11Methods, for example of organic chemistry Houben-Weyl, 4th edition, 1961, Volume 14 / I, are described.

Suitable polymerization products can also be used in which carboxyl groups are subsequently introduced by grafting or hydrolysis are, for example partially saponified polyacrylic esters or graft polymers from carboxyl group-containing monomers to linear or branched polyethers.

The crosslinking according to this variant is carried out in such a way that homo- or copolymers containing the polyoxazoline rings and the component containing carboxyl groups in suitable solvents, such as esters, for example ethyl acetate, butyl acetate, ethylglycol acetate, chlorinated hydrocarbons, such as chlorobenzene, ethylene chloride, hydrocarbons such as xylene, toluene, ethylbenzene, Cyclohexane, hexane, alcohols such as ethanol, butanol, butyl glycol, ethers such as dioxane, Dimethoxyethane, or ketones such as cyclohexanone, acetone and dissolved the reaction mixture after evaporation of the solvent to 100-3000 C, preferably 110-180 ° C, heated. Here, the oxazoline is ring-opened and a crosslinked one is formed. Carboxylic acid ester and three-dimensional network containing cartonamide groups.

Of course, however, the components can also be used without use mixed by solvents with the help of conventional aggregates and then be networked.

The mixing of the starting component can be made so that both components optionally present as a powder and mixing in suitable Devices takes place.

It is also possible to use the starting components for a short time Melting up to temperatures of about 1000 C and after cooling to granulate or pulverize.

However, it is also possible to carry out the crosslinking in an aqueous dispersion.

Have the not yet hardened mixtures of the starting components excellent storage stability, whether as a powder or as a solution or as a dispersion.

The starting components can of course also be mixed directly before processing.

The mixing of the starting components is done in such a ratio carried out that on a carboxyl group 0.01 -.

1 oxazolinyl groups are omitted. Will be an excess of oxazolinyl groups used, products with a lower degree of crosslinking are obtained.

The curing of the mixtures always takes place by heating to 100 - 3000 C, preferably at temperatures between 110 and 1800 C.

The crosslinking times are a few minutes to a few hours and depend on the system used and the processing temperature. The cheapest Processing temperatures and times can be easily determined with simple preliminary tests determine.

It is readily possible to add the mixtures according to the invention the starting materials used or the self-crosslinkable copolymers, auxiliaries, such as fillers, inorganic and organic pigments, stabilizers, antioxidants and add plasticizers prior to molding and crosslinking. Come as fillers For example, carbon blacks of various classifications, precipitated or thermal extracted silicas, silicate-containing, synthetic silicas, kaolins, talc, Chalk, asbestos powder, glass and metal powder, quartz powder, sand, slate powder, and others. in Question0 It was surprising that the process according to the invention can be carried out by simply heating leads to fully networked products, especially from "Journal Polymer Science" volume 4, pages 257-260 - (1966) it was known that the reaction of adipic acid with bis (oxazolines) only succeeds up to a conversion of about 24-61%.

The crosslinked products of the invention have valuable properties such as solvent resistance, weather resistance and chemical resistance as well as good mechanical and dielectric properties. Of particular note is the valuable detergent resistance of the new fabrics.

They can be used for the production of varnishes, coatings, coatings, Adhesives, molding compounds or for the production of a wide variety of moldings Kind be used.

The parts and percentages given in the examples relate to based on weight, unless otherwise noted.

EXAMPLES Preparation of the copolymers used as starting materials for Example 1 A) A mixture of 50 parts of styrene and 40 parts of butyl acrylate and 10 parts of vinyloxazoline in 100 parts of toluene under stirring and nitrogen brought to reflux temperature (about 110 ° C). This is done in drops within 5 hours 2 parts tert. Butyl peroctoate and then stirred for a further 5 hours. the The approx. 50% strength polymer solution obtained is used directly according to Example 1.

B) A mixture of 50 parts of styrene, 40 parts and butyl acrylate 10 parts of acrylic acid is tert together with 1.5 parts. Dodecyl mercaptan to reflux brought and tert therein 0.7 parts within 3 hours. Butyl perpivalate stirs one. The internal temperature rises from an initial 1380 ° C. to 1700 ° C. The mixture is now stirred 0.7 parts of tert-butyl peroxide and sets after a further hour. Vacuum on. The melt is then allowed to solidify on metal sheets. The copolymer will used as an approx. 50 goat solution in toluene for example 1.

Example 1 For the production of one for the painting of washing machines suitable stoving enamel are 100 parts of a copolymer of 50% styrene, 40% butyl acrylate and 10% acrylic acid, which is 50% dissolved in toluene, with 100 parts of 50 show toluene solution of a second copolymer of 50% styrene, 40% butyl acrylate and 10% vinyloxazoline mixed and homogenized by stirring. Then 100 parts of titanium dioxide pigment are added and rubbed over a funnel mill away. After dilution with toluene to spray viscosity (DIN cup, 4 mm: 20 - 22 sec.) you spray the paint on phosphated iron sheets. These are briefly ventilated and baked at 1400 C, 1600 C and 1800 C for 30 minutes. You get high-gloss pure white films, the properties of which are given in the table below. at the stoving temperatures 1600 C and 1800 C consists in the properties of the paint films no difference.

Stoving temperature (30 min.) 1400 C 1600 C Average layer thickness 40 P 40 Cross-cut DIN 53151 HB HB impact elasticity according to Gardner inch / pound 4 + 6 + Erichsen recess (mm) DIN 53 156 6.0 8.4 bending test (sharp edge, jerky) 900 + 1800 + detergent resistance at boiling temperature (hours) * 40 longer than 40 Solvent resistance Films soften somewhat, 5 min. Exposure time to toluene but are not resolved.

Note: + means here and in all of the following examples flawless quality of the coating.

* The painted test panels were exposed to standing in the detergent solution, the lower half of the sheets was covered by lye 0 after 8 hours each time the detergent solution was renewed. A commercially available solution was used to produce the washing liquor Heavy duty detergent from Sunlicht (Mannheim, Germany) dissolved 1 zigzag in water.

As a comparison test, the two components of the paint mix are used individually pigmented, thinned, sprayed on and baked. As expected, that reacts Acrylic acid-containing polymer practically not crosslinked at 2300 C.

The soft varnish can be easily removed with toluene. The vinyloxazoline containing polymer reacts at temperatures above 2000 C with crosslinking. The paints are very yellowed and their surface is blistered.

Production of the starting polymers for example 2 The vinyl oxazoline resin or the acrylic acid resin for example NrO 2 becomes like. described under Å) or B), only that the monomer mixture given in Example NrO 2 instead of the mixture of Example no. 1 is used0 Example 2 One for highly elastic Suitable paintwork (e.g.

for metal strip painting) is produced by moving as indicated in Example 1: A copolymer of 35 96 styrene, 10 96 acrylic acid, 30% butyl acrylate and 25 96 methacrylate is in solution in a ratio of 1: 1 with a second polymer of 20% methyl acrylate, 70% ethyl acrylate and 10% vinyloxazoline mixed. The 50 goat solution in xylene / butyl glycol (1: 1) is also 100 % (based on solids) pigmented with a titanium dioxide pigment and nn on degreased Fe and Al sheets, which are stoved for 30 minutes at 1600 C. The properties of the paint films are summarized in the following table: Stoving temperature (30 min.): 1600 C Average layer thickness: 40 u Cross-cut DIN 53 151: 1 - 2 pencil hardness DIN 46 453: HB Erichsen depression DIN 5315: 10.0 (sheet metal crack) Bending test: 1800 + solvent resistance: paint film slightly (5 min., Toluene) softens, Impact elasticity not swollen: (inch / pound) according to Gardner 80 +. Similar good Results are achieved if you apply the paint film for 1 minute at 3000 C or 2 minutes hardens at 2600 C.

EXAMPLE 3 1 l of desalinated water is removed in a stirred pot under nitrogen Water presented, 8 g of cetyl alcohol sulfonate dissolved therein and then 200 g of a mixture of 95 parts by weight of ethyl acrylate, 4 parts by weight of vinyloxazoline and 1 part by weight of methacrylic acid emulsified. The mixture is heated to 600 ° C. and one each is added dropwise separately over the course of 3 hours Solution of 0.2 g of potassium peroxydisulfate in 50 ml of water and 0.02 g of sodium pyrrosulfite in 50 ml of water. The mixture is then stirred for 6 hours at 600 ° C. and the polymer is precipitated with saline solution. The unusual crumbs are rolled into a fur and with 100 ° C dried. A crosslinked acrylate rubber sheet is obtained which is converted into aromatics no longer solves.

Example 4 In an autoclave, 4 liters of water are added under nitrogen and 40 g of fatty alcohol sulfonate with approx. 14-16 carbon atoms.

After rinsing with ethylene, 140 g of vinyl oxazoline, 100 g of cyclohexyl maleic acid are added, 2000 g of vinyl chloride and pushes in 1000 g of ethylene. It is heated to 700 ° C. and start the reaction by slowly adding 10 g potassium peroxydisulfate in 200 ml of water while stirring vigorously. After 12 hours, the cooled emulsion is drained off and a sample poured onto a glass plate. After drying, it is baked for 10 minutes at 120.0 C and receives a crosslinked film. In contrast to a ~ it is not networked Ethylene-vinyl chloride copolymer film not soluble in acetone.

General manufacturing instructions for the 2-alkenyl-oxazo-line used It is made from the chloride of a, ß-unsaturated carboxylic acid and an aziridine in the usual way - z. B. by reaction in the presence of an equimolar amount of a tertiary amine in an inert solvent - the N-acylaziridine here. By heating the acylaziridine or its solution in the presence of alkali iodides occurs rearrangement to the desired oxazolines, the z. B. by fractional Distillation can be obtained in pure form.

Further manufacturing options: Angewandte Chemie 78, page 921, (1966).

Claims (4)

Patent claims: «.Y Process for the production of high molecular weight, crosslinked substances with recurring units of the formula I CONH CHR2 - CHR3 - OCO, characterized in that polymers of at least one oxazoline of the formula II where R and R1 are hydrogen, alkyl with 1-7 carbon atoms, aryl with 6-10 carbon atoms, R2 and R denote hydrogen or alkyl with 1-3 carbon atoms, and optionally at least one further copolymerizable monomer with di- and Polycarboxylic acids can be crosslinked by heating to temperatures of approx. 100 - 3000 C. 2.) Method according to claim .1, characterized in that copolymers from oxazolines according to the formula II of claim 1 α, ß-unsaturated carboxylic acids with 3 - 5 carbon atoms and optionally other 'monomers without the addition of further di- or polycarboxylic acids are crosslinked by heating to 100-3000 C, the Proportion of copolymerized, ß-unsaturated carboxylic acid not more than 30% by weight, based on the copolymer. 3.) The method according to claim 1 and 2, characterized in that the Crosslinking takes place in substance, solution, emulsion or dispersion. 4.) Crosslinkable mixtures for producing coatings and moldings of polymers from A) at least one oxazoline of the formula where R and R1 denote hydrogen, alkyl with 1-7 carbon atoms, aryl with 6-10 carbon atoms, R2 and R3 denote hydrogen or alkyl with 1-3 carbon atoms, optionally further copolymerizable monomers, free of carboxyl groups, and B ) at least two products containing carboxyl groups with an average molecular weight of at least 600, with 0.01-1 oxazolinyl groups per carboxyl group in the mixtures 5.) self-crosslinkable copolymers containing copolymerized units of 99.7-1.0% by weight , preferably 1 to 30 wt., at least one oxazoline of the formula where R and R1 are hydrogen, alkyl having 1-7 carbon atoms, aryl having 6-10 carbon atoms, R2 and R3 are hydrogen or alkyl having 1-3 carbon atoms, 0.3-30% by weight, preferably 0 , 3-15% by weight, at least one α-, ß-unsaturated carboxylic acid with 3-5 carbon atoms and 0-98.7% by weight, preferably 45-98.7% by weight, at least one other copolymerizable monomers, the sum of the percentages by weight always being 100.