DE2111332A1 - Process for the production of copolymers - Google Patents

Description

The invention relates to a process for the production of copolymers. From the German exposition 1 102 410 stoving enamels are known that

I. organic solvents and

II. Copolymers from

A) esters of acrylic or methacrylic acid with alkanols,

B) Ethers of N-methylolacrylic or methacrylic acid amide with alkanols or phenylalkanols,

C) Monoesters of acrylic or methacrylic acid with polyvalent hydroxyl compounds, and optionally Additionally

D) other compounds containing an ethylenically unsaturated, copolymerizable group, such as acrylonitrile, Contain acrylic and methacrylic acid, higher esters of ethylene carboxylic acids, styrene and vinyl acetate. Such stoving enamels are characterized by a number of valuable properties.

The object of the present invention is to produce film-forming copolymers which are soluble in organic solvents Styrene, acrylic acid, N-alkoxyalkylacrylic acid amides or N-alkoxyalkyl methacrylic acid amides, Hydroxyalkyl acrylates, hydroxyalkyl methacrylates and alkyl acrylates by special Establish selection measures suitable for the manufacture of improved stoving enamels.

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The invention relates to a method for production of film-forming copolymers soluble in organic solvents by copolymerization of Styrene, acrylic acid, N-alkoxyalkylacrylic acid amides or N-Alkoxyalkylmethacrylsäureamiden, Hydroxyalkylaerylaten, Hydroxyalkyl methacrylates and alkyl acrylates in organic solvents in the presence of polymerization initiators and regulators, characterized in that a mixture consisting of:

(a) 15 to 65 wt. Styrene,

(b) 2 to 12 wt. 56 hydroxyethyl methacrylate, hydroxy

propyl methacrylate, hydroxyethyl acrylate or hydroxypropyl acrylate,

(c) 1 to 3 wt. Acrylic acid or methacrylic acid,

(d) 12 to 30 parts by weight of an ether of N-methylolacryl-

or methacrylamides with a saturated alkanol containing 1 to 8 carbon atoms owns,

(e) 10 to 55 wt. an ester of acrylic or meth

acrylic acid with a saturated one having 1 to 10 carbon atoms Alkanol or a mixture of such esters and

(f) 2 to 15 wt. Hydroxyalkyl ester of methacrylic acid

or acrylic acid of the following formula

H ₂ C = CC

0-CH ₂ -CH

CH

0-CH ₂ -CH

CH 1

O-CH ^ -

η OH

where η represents numerical values between 2 and 6, R is hydrogen or is a methyl group and the compound of formula (I) or their mixtures have hydroxyl numbers of about 100 to about 200, where the sum of the percent

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numbers of the connections marked with (a) to (f) is each 100, is copolymerized by heating.

A special preferred embodiment of the method is characterized in that a mixture consisting of:

(a) 30 to H5 percent by weight of styrene,

(b) 5 to 10 wt. Ϊ hydroxyethyl methacrylate,

(c) 1 to 2 per weight unit of acrylic acid,

(d) lü to 22 wt. S of the ether of N-methylol methacrylic

amides with n-butanol or isobutanol or their mixture,

(e) 25 to 35 weight percent butyl acrylate or 2-ethylhexyl acrylate

or their mixture, and

(f) 5 to 10% by weight of the JC hydroxy alley ester of methacrylic acid with hydroxyl numbers from about 130 to about 150 is copolymerized.

Another preferred embodiment of the method is characterized in that as a monomeric ether of N-methylolraethacrylamide with n-butanol or isobutanol the mixture of the reaction products of methacrylamide, paraformaldehyde, butanol and / or isobutanol, the Molar ratios based on 1 mole of methacrylamide, 1 to 1.5 moles of paraformaldehyde and 1 to 3 moles of n-butanol or isobutanol and an acid or an acid-donating catalyst is present in the manufacture has been used for copolymerization.

A special further embodiment of the method is characterized in that such an ether of N-methylol methacrylamide with n-butanol or isobutanol uses, which contains the catalyst or its esterification products in its solution and where-

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has been used as a catalyst for maleic anhydride.

Ethers of N-methylolacrylic are used as component (d) or methacrylamides with saturated alkanols containing 1 to 8 carbon atoms such as methanol, ethanol, propanol, n-butanol, isobutanol, pentanol, hexanol, heptanol, Containing octanol or 2-ethylhexanol are used. Ethers of N-methylolacrylamide or methacrylamide are preferred with isobutanol or n-butanol.

The particularly preferred ethers of N-methylol methacrylamide with n-butanol or isobutanol are made by a particularly suitable reaction of the reactants in the ratio of 1 mole of methacrylamide, 1 to 1.5 moles of paraformaldehyde with 1 to 3 moles of n-butanol or isobutanol and maleic anhydride in the Receive heat with extensive water separation. A reaction product with ratios of the reactants of 1 mole of methacrylamide, 1.2 moles of paraformaldehyde and 2 moles of n-butanol or isobutanol and 0.01 to 0.03 moles of maleic anhydride is most suitable. The reac tion mixture of methacrylamide used, paraformaldehyde, n-butanol and maleic anhydride delivers to the reaction about 65 wt £ + ^ 3 wt -.% Ether of N-methylolmethacrylamide with n-butanol and about 35 wt -.% £ 3 wt .- /? n-butanol, while in the conversion of methacrylamide, paraformaldehyde, isobutanol and maleic anhydride a product of approx. 64% by weight? + _ 3 wt -.% Ether of N-methylolmethacrylamide with isobutanol and about 36 wt -.% _ + 3 wt .-% isobutanol is obtained.

The most preferred embodiment of the method is in that one is called the ether of N-methylol methacrylamide with n-butanol, the reaction mixture solution from the

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Conversion of 4 moles of methacrylamide, 4.67 moles of paraformaldehyde, 8 moles of n-butanol and 0.03 moles of maleic anhydride obtained with separation of water, used. Such a reaction mixture contains about: 64.0 wt .- # of the ether of N-methylol methacrylamide

with n-butanol, 32.5 wt -.% of butanol, 0.8 wt .- / 5 paraformaldehyde, 1.6 parts by weight? Water, 0.6 wt .- /? Methacrylamide and 0.5 wt -.% Monobutyl maleate.

Another reaction approach, which also belongs to the most preferred embodiment of the process, exists in that as the ether of N-methylol methacrylamide with isobutanol, the reaction mixture solution from the Conversion of 4 moles of methacrylamide, 4.67 moles of paraformaldehyde, 8.0 moles of isobutanol and 0.03 moles of maleic anhydride under "keep water separation, begins.

Such a reaction preparation contains about:

63.4 wt -.% Of the ether of N-methylolmethacrylamide with

% Paraformaldehyde, 1.5 parts by weight f of water, 0.8 wt - - isobutanol, 33.0 wt -.% Of isobutanol, 0.8 wt..% Methacrylamide and 0.5 wt -.% Maleinsäuremonoisobutylester.

If the ether of N-methylol methacrylamide is added to isobutanol with the monomers mentioned under a) to f) Compounds, products are obtained which, after stoving, give hard surface finishes. However, if a product is required which should show more elastic properties after the stoving process,

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so one puts a copolymer with the ether of N-methylolacrylamide with n-butanol and the under a) to f) mentioned monomeric compounds.

As component (e), esters of acrylic or methacrylic acid with 1 to 10 carbon atoms are used saturated monoalkanol, such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-isobutyl acrylate or 2-ethylhexyl acrylate is used. Butyl acrylate, isobutyl acrylate or 2-ethylhexyl acrylate are preferred used.

Hydroxyalkyl esters of methacrylic acid or acrylic acid, the esterification products, are used as component (f) from methacrylic acid or acrylic acid and polypropylene glycol are used.

The polypropylene glycol residues contained in component (f) have a molecular weight of about 200 to about 500. These hydroxyalkyl esters of methacrylic acid or acrylic acid have hydroxyl numbers from about 100 to about 200. The particularly preferred hydroxyalkyl esters of acrylic or methacrylic acid have hydroxyl numbers from about 130 to about 150.

Suitable solvents for the copolymers according to the invention are the customary, for example alkylbenzenes, such as Toluene and xylene, alcohols such as n- and iso-butanols, monoethers of diols such as ethanediol monomethyl ether, Esters of alkanols, such as ethyl acetate, and monoether monoesters of diols, such as Äthandiolmonomethylmonoessigsäureester, as well as mixtures of such substances with one another or with petrol hydrocarbons.

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The copolymers can be prepared in a customary manner, generally expediently by Solution polymerization in solvents that are also part of the finished stoving enamels should. The polymerization can expediently by means of the customary initiators or initiator systems can be initiated from initiators and activators.

All compounds which form free radicals under the reaction conditions are suitable as polymerization initiators for the process according to the invention. Preferred are peroxy compounds and azo * nitrile. Examples of suitable peroxy compounds are dibenzoyl peroxide, dilauroyl peroxide, dimethyl peroxide, diethyl peroxide, di-tert-butyl peroxide, dioctadecyl peroxide, t-butyl peroxypivalate, disuccinoyl peroxide, urea peroxide, peracetic acid and perbenzoic acid, peracetic boron and perbenzoic acid alone or in combination with one or more perbenzoic peroxy peroxylic peroxylic perbenzoic acid and perbenzoic acid, alkoxidesulfate dialkyl percarbonates alone, peroxy-sulfate dialkyl peroxide, di-tert-butyl peroxide, di-tert-butyl peroxide . Examples of suitable azonitriles are 1,1-azodicylcohexanecarbonitrile, α, α'-azobis- (α-cyclopropylpropionitrile), α, α'-azobis- (isobutyronitrile), α, α'-azobis- (α, γ-dimethylvaleronitrile), α, α ¹ -Azobis- (a-methylenanthronitrile), a, a'-Azobis- (a-phenylpropionitrile), (^ aja'-Azobis-Ca-cyclohexylpropionitrile), aja'-Azobis- (a-methyΙ-γ- carboxybutyronitrile), disodium-v, γ'-azobis- (γ-cyanovalerate), 1,1'-azodicamphan carbonitrile.

By using the usual regulators, such as mercaptans and aldehydes, the degree of polymerization and thus the viscosity of the copolymers is reduced to the desired level Measure set. As a chain-regulating memory

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tans come butyl mercaptans, octyl mercaptans, lauryl mercaptans and tert-dodecyl mercaptan are preferably used.

A preferred process for preparing the new copolymers consists in adding to the refluxing solvent mixture consisting of xylene / n-butanol or xylene / isobutanol, the ratio of xylene to n-butanol or isobutanol from 1: 10 to 2: 1 Can be parts by weight, the monomer mixture including the polymerization catalysts and chain regulators separately or as a mixture over a period of about one to ten hours can be run in uniformly, the Polymerisatxonemperaturen should be between 60 ° C to about 125 ° C. The polymerization is then continued for about 6 to 14 hours in order to achieve as complete a conversion as possible of the monomers. In order to exclude with certainty gelation during the polymerization, the polymerization temperature should briefly not exceed 130 ⁰ C in the above-mentioned mixed solvents, but preferably remain in the indicated temperature range of 60 to 125 ° C.

In the preferred embodiment of the process, the polymerization initiators or catalysts are used in amounts of 0.8 to 1.5% by weight , based on the weight of the monomer mixture, di-tertiary butyl peroxide being used most suitably.

In the preferred embodiment of the method the chain regulators in amounts of 0.5 to 1.5 wt .- ^, based on the weight of the monomer mixture, most suitable tertiary dodecyl mer-

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kaptan is used.

The quantitative as well as special qualitative selection of the monomeric components (a) bis (f) achieved improvements in the copolymers and the stoving enamels which can be produced with them were surprising and unpredictable.

Particularly suitable copolymers which are dissolved in a 50% strength by weight mixture of xylene / n-butanol or xylene / isobutanol are those which have a Gardner-Holdt viscosity of I to Z at 20 ^° C.

The copolymers according to the invention are particularly notable for the fact that they are improved Have pigment binding capacity and those produced with them Coatings show their valuable properties even at relatively low stoving temperatures practically fully develop. Furthermore, paints produced with such copolymers are used for paints with improved adhesion and shock resistance as well as with particularly pronounced elasticity, weather resistance, Preserved hardness and saponification resistance. If desired, paintwork can also be used can be obtained that also have other properties such as light resistance, flexural strength, solvent resistance and have a particularly high temperature resistance.

Stoving enamels can be prepared from the copolymers according to the invention, which, if desired, contain the usual baking enamels with additives such as pigments, soluble dyes, optical brighteners, as well as means to promote leveling and gloss * In particular, the baking finishes to-

1 098A1 / 1624

in addition to the copolymers customary other paint binders, such as alkyd resins, amino resins, phenolic resins, epoxy resins, cellulose derivatives and polymers, which are not identical to the copolymers of this invention, dissolved and / or dispersed contain. The weight ratio of the copolymers to the additional other paint binders should be in general expediently greater than 1, in particular greater than 2. The addition of the usual Other paint binders to the copolymers must be coordinated in terms of type and amount so that clear solutions are obtained and obtained clear films after the baking process. It has also generally proven to be useful when the weight ratio of solvents to the total proportion of binder in the stoving enamels from about 0.4 to 3, in particular from about 0.6 to 1.5 amounts to,

To produce coatings, the stoving enamels based on the new copolymers can be applied to the objects to be coated using the customary methods, for example by spraying, brushing on, pouring on, rolling on, flooding, dipping or soaking. The stoving of the finishes can generally expediently be carried out at temperatures from about 120 to 180.degree. C., in particular from about 130 to 150.degree. C. and, depending on the temperature, over a period of from about 5 to 120 minutes, in particular from about 20 to KO Minutes. Since the valuable properties of the paintwork come into their own especially on metals such as iron, aluminum, magnesium and alloys of these metals, the stoving paints are particularly suitable for painting objects made of sheet metal, e.g. parts of car bodies, ships, washing machines and ice boxes, as well as Cans, jugs,

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Vats and appliances for industry and household. The stoving enamels can also be used for Use making base and top layers; they are also very suitable because of their adhesive strength good for producing single-layer coatings on metals, with the high surface gloss in general makes repolishing unnecessary.

When the finishes are to be baked at the lowest possible temperatures and / or baked enamels are used that contain relatively little acrylic or methacrylic acid polymerized in the copolymer, it may be useful to bake the stoving enamels in the presence of curing agents. Own as such Acids or substances that split off acids, such as p-toluenesulphonic acid, are common for curing polymers, Phosphoric acid, maleic acid or tartaric acid. The amount of curing agent should generally be appropriate from about 0.01 to 5, in particular from about 0.1 to 2% by weight of the copolymers.

The stoving enamels are preferably used with the identified copolymer as the sole binder for single-layer enamels used. However, if stoving enamels or multi-layer stoving enamels with particularly high solvent resistance and excellent surface hardness and gloss retention when exposed to weathering are required, the marked copolymers are used in combination with aminoplasts.

Preferred aminoplasts are condensation products of formaldehyde and melamine, about 4 per mole of melamine up to 6 moles of formaldehyde either weakly acidic or weakly basic have reacted and with Butanol, isobutanol or methanol almost completely

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about 80 to 100 % should be etherified. The resulting urase products should have a molecular weight of about 300 to 1200 and be soluble in organic solvents such as xylene and n-butanol, isobutanol, methanol or glycol ethers and other alcohols. Formulations for suitable melamine resins can be found as examples in Swiss Patent 480 380 and in German Auslegeschrift 1,127,083.

The copolymer and the aminoplast are dissolved in the organic solvent in a ratio of 65 to 95 parts by weight of the copolymer and 5 to 35 parts by weight of the aminoplast resin. The proportions of the copolymers and the alkylated aminoplast are to be chosen so that the two components are compatible both in the coating solution and in the finished film. Any suitable concentration of the copolymer and the aminoplast in the solvent, for example from 1 to 50% by weight, can be used under this condition. If a pigment is present, the total solids content in the coating composition is between 5 and 75% by weight . The ratio of pigment to binder (copolymers plus aminoplast) can be between 1:20 and 1: 2.

The parts and percentages given in the examples are based on weight.

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co

00 ro

Copoly- component component component Component (d) component Component Viscosity according to merisat (a) in (am (c) in in wt -.% (a in Gew.-SS Gardner-Eoldt Weight pc Wt .- / S Weight % Weight-J2 50 wt -.% In Xylene / butanol im Weight ratio 1: 1 "at 20 ° C ge measure up A. 15 - 35 2 - k 1 - 2 12-15 ko - 70 2-5 U-W Styrene Eydroxy Acrylic acid Methyl ether Ethyl- Kydroxyalkyl ethyl meth- of N-methylol- acrylate ester of meth acrylate acrylamide acrylic acid acc. Formula (I) Hydroxyl Number 150 B. 15-30 2-5 2-3 1U - 18 IiO - 65 2-5 W-Y Styrene Eydroxy Methacrylic n-propyl ether Methyl- Hydroxyalkyl propylmeth- acid of N-methylol- acrylate ester of meth acrylate acrylamide acrylic acid acc. Formula (i) Hydroxyl Number 150 ■; c 15-30 5-10 1 - 2 18-25 5-15 1+ - 8 Styrene Hydroxy Acrylic acid n-butyl ether Methylmeth- Hydroxyalkyl W - Ϊ propyl of N-methylol- acrylate ester of meth acrylate acrylamide 35-65 acrylic acid acc. Ethyl- Formula (i) acrylate Hydroxyl Number 150

LO I

CJ

O CD OO

σ> ro

Copoly- component component component Component (d) component Component Viscosity according to merisat (a) in (am (c) in in wt -.% (a in wt -.% Gardner-Koldt Gew.-JS Weight £ Weight % Weight % 50 wt -.% In Xylene / butanol im Weight ratio s 1: 1 at 20 ° C ge measure up D. 15-30 5 - 10 2-3 15-20 10-30 10-15 X-Z Styrene Hydroxy Meth Methyl ether Methylmeth- Hydroxyalkyl ethyl meth- acrylic acid of M-methylol- acrylate ester of acrylic acrylate acrylamide 20 - 50 acid according to formula 2-ethyl (I), kydroxyl hexyl number 110 acrylate £ 30-65 U - 8 1 - 2 12 - 25 15 - 50 3-8 R-V Styrene Hydroxy Acrylic acid n-butyl ether 2-ethyl Hydroxyalkyl propylmeth- of N-methylol- hexyl ester of acrylic acrylate methacrylamide acrylate acid according to formula (I), hydroxyl number 150 F. 35-50 k - 8 2-3 18-27 20 - kO 1+ - 10 T-X Styrene Hydroxy Meth n-butyl ether Butyl Hydroxyalkyl ethyl meth- acrylic acid of N-methylol- acrylate ester of meth acrylate methacrylamide acrylic acid acc. Formula (I), Hy- hydroxyl number 150

4 = -

co OO ■ Ρ "

CP ro

Copoly component component component Component (d) "Component Component Viscosity according to mer is at (a) in 00 in (c) in in wt -.% (a in wt -.% Gardr.cr-Holdt Gev .-% Gev .- # Weight % Weight % 50 Gev .- ^ ig in Xylene / butanol im Weight ratio 1: 1 at 20 ° C ge measure up G 30 - 1 * 5 U - 8 1 - 2 15-25 20 - 1 + 5 U - 15 U-Y Styrene Hydroxy Acrylic acid n-butyl ether Octyl Hydroxyalkyl propyl of N-methylol- acrylate ester of meth acrylate methacrylamide acrylic acid acc. Formula (I), Hy- hydroxyl number 150 H 15 - 35 5 - 8 1 - 2 12 - 25 10 - kO 5 - 12 T-X Styrene Hydroxy Acrylic acid n-butyl ether Octyl Hydroxyalkyl ethyl- of N-methylol- acrylate ester of meth acrylate with hac rylamid 10 - ItO acrylic acid acc. ethyl- Formula (I), Hy- acrylate hydroxyl number 18O I. 25-55 5 - 8 2-3 15-30 20 - 50 5-15 T-X Styrene Hydroxy Methacrylic Octyl ether of n-butyl Hydroxy alkyl ethyl- acid N-methylol acrylate ester of meth acrylate acrylamide acrylic acid acc. Formula (l) _s Hy- hydroxyl number 150

VJl I

NJ

OO

Copoly component component component Component (d) component Component Viscosity according to mer! sat (a) in (*>) in (c) in in wt -.% (a in Gev .- $ Gardner-Holdt Gev .-% Weight % Gev .-% Gev.-S 50 wt. In Xylene / butanol im Weight ratio 1: 1 at 20 ° C ge measure up ;
———— ^ I J 30-65 h - 10 1 - 2 15-30 20 - 50 5 - 8 Styrene Hydroxy Acrylic acid Octyl ether of Decyl Hydroxyalkyl T-Y propyl N-methylol acrylate esters of acrylic acrylate acrylamide acid according to formula (I), hydroxy1- ¹ number 200 K 30-50 5-10 1.5-2.5 18-22 25-35 5 - 8 U-X Styrene Hydroxy Acrylic acid n-butyl ether n-butyl Hydroxyalkyl ethyl- of N-methylol- acrylate ester of meth methyacry- methacrylamide acrylic acid acc. lat Formula (I), Hy- hydroxyl number 150 L. 35 - ^ 5 5-10 1 - 2 18-22 25-35 5-10 U-I Styrene Hydroxy Acrylic acid n-butyl ether 2-ethyl Hydroxyalkyl ethyl meth- of N-methylol- hexyl ester of meth acrylate methacrylamide acrylate acrylic acid acc. Formula (I), Hy- hydroxyl number 150 I.
- ... J

Copoly- component Connoisseur component Component (d) component Component Viscosity according to I. aerisat (a) in (am (c) in in wt -.% (a in wt -.% Gardner-Holdt Weight % Gew.-JS Gev. ^% - : Weight # 50 wt. In Xylene / butanol iia Weight ratio 1: 1 at 20 ° C ge measure up M. 30 - Iv5 k - 10 1 -2 18-22 25-35 5-10 T-X Styrene Hydroxy Acrylic acid i-butyl ether n-butylr Hydroxyalkyl ethyl meth- of H-methylol- acrylate ester of meth- ' acrylate methacrylamide acrylic acid acc. Formula (I), Hy- hydroxyl number 150 N 35 - 1 * 5 5 - 8 1 - 2 18-22 25-35 5 - 8 T-Y Styrene Hydroxy Acrylic acid i-butyl ether 2-ethyl Kydroxylalkyl ethyl meth- of li-methylol- hexyl ester of meth acrylate methacrylamide acrylate acrylic acid acc. Formula (I), Hy- hydroxyl number I50

example 1

Preparation of the copolymer solution 1

In a flask equipped with a stirrer, reflux condenser and thermometer, a mixture is Consists of 317 g of xylene and I63 g of n-butanol, under Add the following mixture to the boil in a four-hour steady feed:

225 g styrene, 11 g acrylic acid, 30 g hydroxyethyl methacrylate, 175 g 2-ethylhexyl acrylate, 9 g tert -dodecyl mercaptan, 8 g of di-tert-butyl peroxide, 43 g a 70% strength by weight xylene solution of the hydroxyalkyl ester of methacrylic acid, which is an esterification product of methacrylic acid and polypropylene glycol with a hydroxyl number of about 130 and 184 g of a 65 wt .- # strength butanolic solution of the Ether of N-methylol methacrylamide with n-butanol, which is present as part of a reaction mixture, made from four moles of methacrylamide, 4.67 moles of paraformaldehyde, 8 moles of n-butanol and 0.03 Moles of maleic anhydride in the heat with extensive water separation.

Subsequently, another is polymerized for 8 to 10 hours under boiling until the solution has a body content of 50 wt -.%, And the viscosity of W to Y, as measured by Gardner-Holdt at 20 ° C.

Use of the copolymer 1

54 g of this copolymer solution 1 are mixed with 32 g Titanium dioxide pigment (rutile) and 9 g of xylene and 2.5 g of ethyl glycol acetate for 24 hours on a ball mill homogenized. After subsequent dilution to spray viscosity with a mixture of xylene and Ethyl glycol is the sprayable stoving enamel on zinc-phosphated steel sheets as well as untreated ones

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Steel sheets coated, and baked between 150 to 13O ⁰ C in 30 minutes.

Baking temperature
doors and times 30 '150 ⁰ C -15 * 180 ° C 30 »180 ° C Pendulum hardness according to
king 148 » 147 " Buchholz hardness 125 133 133 Scratch resistance 1-2 1- 1

1 = The paint surface cannot be damaged by a scratch test with a fingernail

2 = Paint surface is by scratch test with the fingernail scratchable

elasticity

Burn-in tempera
doors and times 30 »150 ° C 15 * 180 ° C 30 '180 ⁰ C Erichsen cupping
Deep-drawn sheet 7.7 mm 7.2 mm 6.8 mm Erichsen cupping
Bonder plate 97 4.5 mm 4.9 mm 4.0 mm Dornbie ge attempt
ASTfI D 522
ErichsenbIech 0 0 0 Mandrel bending test
ASTM D 522
Bonderblech 97 0 0 1
, _. _r .._..._.

0 = perfect

1 = 0.1-0.5 cm torn

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Burn-in tempera
doors and times 30 '150 ⁰ C 15 ^f l80 ° e 30 »180 ° C Long shine,
measured in the win
kel 45 ^δ 103 % 108 Ji 99 %

Resistances

Burn-in
temperatures
and times layer
strength
Dry
Movie 30 * IiIO ⁰ C I 30 * 150 ° C 15-18O ° C Detergent solution Burden
duration
3 rounds 0 0 0 Detergent solution 4 rounds gl mo-ml 0 0 Xylene 6 ' 1 0 0

1 round = 2.5 # ige Jufsung, 8 hours of cooking, 16 hours in lye at room temperature

g = 0 no bubbles gl = bubbles barely visible with eyes g2 = slightly larger bubbles m = amount of bubbles mo = no bubbles ml = 20ί bubbles on the surface m2 = U0% bubbles on the surface

Xylene 0 = not attacked

1 = surface scratchable, no swelling

2 = surface scratchable, slight swelling

3 = scratchable paint film, slight swelling

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Salt spray test according to ASTM B 117-1

Branded
temperatures U.
times Load
duration 30 » 150 ° C 15 ^f 180 ° C 30 » 180 ° C Bonder plate
97 240 h 0-1 , 0 mm 0-1 , 0 mm 0-1 , 0 mm Bonder plate
97 500 h l ₃ 0-2.0mm 0-1 , 0 mm
* 1 0-1 , 0 mm

Infiltration at the St. Andrew's cross is given in mm.

Kesternie test

5 rounds blow blow blow Bonder plate 97 0 0 0

The sheets are in a chamber with 300 ltr. The volume is attached, in which there is a temperature of 40 + _ 3 ⁰ C and 100% relative humidity. In addition, 2 ltr. Sulfur dioxide Introduced into the closed chamber (cabinet according to Kesternieh) 1 round = 8 hours exposure as described above and hours at room temperature,

Therm. Al
at
ifco ° c ' 0 h d. 100 hours 200 SM, 300 hours IOO hours 500 hours Shine after
Long 1 * 5 102 105 10% 105 10U 10U Validity -11 -11.5 +1 +15 +21 +26

The yellowing is measured with the leukometer compared to Mag nesium oxide measured as normal white

The value 0 »Mg 0
Minus values whiter than Mg O
Plus values more yellow than Hg 0

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* 22 -

compatibility with alkyd resins im turned
burned
Movie ₂ 2>
in solution I.
im turned
burned
Movie Mixing ratio
ratio, mixed
polymer /
Alkyd 1"
in solution
S. compatible
lich compatible
lich compatible
lich 90:10 compatible
lich ti ti ti 75:25 η Il It ti 50:50 η Il dd η 25:75 η It H ti 10:90 η

1 'alkyd resin consisting of 33 pounds of ricin oil, trimethylol

propane and phthalic anhydride

2 alkyd resin composed of 40 pounds of ricin oil, glycerine and

Phthalic anhydride.

Comparative experiment

In a comparative experiment, the procedure is the same as that given in Example 1, with the exception that when preparing the copolymer instead of hydroxyalkyl esters from methacrylic acid and Polypropylene glycol the same amount of hydroxyethyl methacrylate is used. The data is on a bonded steel sheet (Bonder 97) has been determined by means of a coated lacquer and in reproduced in the table.

Stoving conditions
150 ° C 30 ^f according to the invention
example 1 Comparison
attempt Erichsen cupping 4.5 mm 2.3 ram Mandrel bending test
according to ASTM D 522
about a 6mm
mandrel perfect Painting
flakes off

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The new copolymers of the present invention show the lacquer behavior in all previously known binders a sum of excellent properties, which in general only through several binders and then only in some areas for the surface protection of sheet metal. The mechanical behavior as well as the surface hardness, elasticity and resistance to washing lye and solvents, as well as the hardly occurring yellowing, show that binders with completely surprising, unexpectedly optimal properties are present.

Use of the copolymer 1 in a one- coat paint

Parts by weight : Ingredients : 52.00 Copolymer 1

2.00 epoxy resin based on bisphenol A and epichlorohydrin with an epoxy equivalent weight of 450-525 »an epoxy value of 0.19-0.22 and a Durrans softening point of 65 ° 75 ° C

32.00 titanium dioxide (rutile)

6.10 xylene

2.00 Solvesso 150 (solvent)

3.00 ethyl glycol acetate

1.00 silicone oil L 050 lfcig in xylene

1.90 Bentone 34 paste 10tfig in xylene 10000

Gardner-Holdt viscosity "J" at 20 ^° C.

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Binder: pigment ratio = approx. 1: 1.2 Adjustment to spray viscosity with solvent mixture.

Solvent mixture:
35.00 xylene
20.00 butanol
30.00 Solvesso 150
15.00 ethyl glycol acetate

Stoving conditions;

30 min. - IiJO ⁰ C - 150 ° C 15 min. - 170 ° C - 180 ° C

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Claims (7)

Claims Process for the preparation of in organic solvents soluble film-forming copolymers by copolymerization of styrene, acrylic acid or methacrylic acid, N-alkoxyalkylaery1-acid amides or N-alkoxyalkyl methacrylic acid amides, Hydroxyalkyl methacrylates or hydroxyalkyl acrylates and alkyl acrylates in organic Solvents in the presence of polymerization initiators and regulators, characterized in that that a mixture consisting of: (a) 15 to 65 wt -.% styrene, (b) 2 to 12 wt -.% hydroxyethylmethacrylate, hy- hydroxypropyl methacrylate, hydroxyethyl acrylate or hydroxypropyl acrylate, (c) 1 to 3 wt -.% of acrylic acid or methacrylic acid, (d) 12 to 30 wt -.% of an ether of N-methylol acrylic or methacrylamides with a saturated alkanol, the Has 1 to 8 carbon atoms, (e) 10 to 55 wt -.% of an ester of acrylic or Methacrylic acid with 1 to 10 carbon atoms saturated alkanol or a mixture of such esters and (f) 2 to 15 wt -.% hydroxyalkyl esters of methacrylic acid or acrylic acid with the following formula
R, 0 H ₂ C = CC. ¹ O-CH ₂ -CH CH,
I ³
0-CH ₂ -CH- CH-I ^: 0-CH ₀ -CH ² I.
OH (I) 109 8 41/1624 where η represents numerical values between 2 and 6 , R is hydrogen or a methyl group and the compound of the formula (I) or their mixtures have hydroxyl numbers from about 100 to about -200, the sum of the percentages of those with (a) to ( f) each of the compounds designated is 100, is copolymerized by heating. 2) Method according to claim I, characterized in that a mixture consisting of: (a) 30 to 45 wt -.% styrene, (b) 5 to 10 wt .-? hydroxyethyl methacrylate, (c) 1 to 2 wt. Acrylic acid, (d) 18 to 22 wt. an ether of N-methylol- methacrylamides with n-butanol or isobutanol or their mixture, (e) 25 to 35 wt. Butyl acrylate or 2-ethylhexyl acrylate or a mixture thereof, and (f) 5 to 10 wt. Hydroxyalkyl ester of methacryl acid with hydroxyl numbers from about 130 to about 150 contain, is copolymerized. 3) Method according to claim 1 or 2, characterized in that the ether of N-methylol methacrylamide Reaction products of methacrylamide, paraformaldehyde, butanol with n-butanol or isobutanol and / or isobutanol, the molar ratios based on to 1 mole of methacrylamide, 1 to 1.5 moles of paraformaldehyde and 1 to 3 moles of n-butanol or isobutanol and an acid or an acid-donating catalyst is present in the manufacture has been, is copolymerized. 109841/1624 4) Method according to one of claims 1 to 3, characterized in that such ethers of N-methylol methacrylamide be used with n-butanol or isobutanol, which in their solution the catalyst or whose esterification products contain and wherein maleic anhydride has been used as a catalyst. 5) Use of the copolymers obtainable by the processes mentioned in claims 1 to 3 as a binder or sole binder for stoving enamels. 6) An organic solvent-soluble, film-forming copolymers consisting of a: (a) 15 to 65 percent by weight? Styrene, (b) 2 to 12 wt -.% hydroxyethylmethacrylate, hy- hydroxypropyl methacrylate, hydroxyethyl acrylate or hydroxypropyl acrylate, (c) 1 to 3% by weight acrylic acid or methacrylic acid, (d) 12 to 30 wt -.% of an ether of N-methylol acrylic or methacrylamides with a saturated alkanol, the Has 1 to 8 carbon atoms, (e) 10 to 55 wt -.% of an ester of acrylic or t Methacrylic acid with 1 to ΊΟ carbon atoms saturated alkanol or a mixture of such esters and (f) 2 to 15 wt. 5? Hydroxyalkyl esters of methacrylic acid or acrylic acid of the following formula
R .0 H ₀ C = CC CH, 2 \, 3 CH I.
0-CH ₂ -CH CH I
0-CH ₂ -CH I (D η OH 1 098 41/1624 where η represents numerical values between 2 and C , R is hydrogen or a methyl group and the compound of the formula (I) or their mixtures have hydroxyl numbers of about 100 to about 200, the sum of the percentages of those denoted by (a) to (f) Compounds each 100 is copolymerized by heating. 7) A film-forming one soluble in organic solvents Copolymers consisting of: (a) from 30 to k5 wt -.% styrene, (b) 5 to 10 wt -.% Ilydroxyäthylmethacrylat, (c) 1 to 2 wt -.% acrylic acid, (d) 18 to 22 wt -.% of an ether of N-methylol methacrylamides with n-butanol or isobutanol or their mixture, (e) 25 to 35 percent by weight of butyl acrylate or 2-ethylhexyl acrylate or a mixture thereof, and (f) 5 to 10 wt -.% hydroxyalkyl esters of methacrylic acid with hydroxyl numbers from about 130 to about 150. 109841/1624