BE681935A - - Google Patents

Description

  

   <Desc / Clms Page number 1>
 



  "Coating compositions containing polymerized alkyl methacrylates"

 <Desc / Clms Page number 2>

 
The present invention relates to thermosetting coating compositions containing inter-polymers of unsaturated esters containing hydroxyl groups. It relates in particular to such interpolymers and to such compositions modified by the inclusion acid groups which have reacted with an imine in order to improve their properties.



   Interpolymers of hydroxyalkyl esters are used, along with other resin components, to provide coating compositions for various articles. An advantageous application is that of the manufacture of coating compositions for motor vehicles and other vehicles.

   Heat-curable coatings based on these polymers may have. many outstanding properties including excellent gloss retention, good solvent resistance, good durability, etc. However, these compounds also have certain disadvantages; for example; it is difficult to obtain uniformly pigmented compositions, especially in black coatings and metallic or polychromatic paints. The adhesion between successive layers also poses a constant problem.



   It has now been found that the overall properties of coatings based on hydroxyalkyl ester interpolymers are greatly improved by the inclusion of a small proportion of acid units in the vehicle.

 <Desc / Clms Page number 3>

 polymer and by reacting these acid groups with an alkylene imine or a substituted alkylene imine. Coatings in which these imipe modified acid units are incorporated into the film forming component or component exhibit exceptional adhesion to most surfaces, including other paints and basecoats, while they are pigmented coatings of exceptional quality.

   Thus, through metallic paints, these vehicles ensure a uniform appearance and orientation of the metallic flakes, for example aluminum, which contributes to obtaining maximum gloss. Further, the pigmentation of these products, when using pigments, such as carbon black, is accomplished with extraordinary ease and without the difficulties heretofore encountered.



   (The process for dispersing the pigments in these products is further described in the Belgian patent application filed.
 EMI3.1
 Patented June 1, 1966 as No. 9 '' y. In addition, the excellent overall properties of the corresponding compositions containing no imine modified units are maintained and in many cases improved.



   The thermosetting coating compositions of the present invention contain, as the main film-forming component of their vehicle, an interpolymer of from about 2 mole percent to about 25 mole percent of a hydroxyalkyl ester of a carboxylic acid. ethylenically linked, from about 0.1 mole percent to about 20 mole percent of a linked carboxylic acid

 <Desc / Clms Page number 4>

 ethylenic and at least one other ethylenic monomer, 1 ',' Ù At least about 0.1% by weight of polymerized acidic carboxylic units modified with an imine, relative to the total weight of the imine, is incorporated into the composition. interpolymer.



   Acid imine-modified units are obtained by reacting an alkylene imine with vinyl-polymerized monomeric ethylenic acid units, which preferably constitute all or part of the acidic monomer interpolymerized with the hydroxy-alkyl ester. acid and other monomers. However, the imine-modified acid units may also be contained in a polymer mixed with the interpolymer, such as a polymer formed from an acid and the other desired monomers in the polymer. The composition, or other polymer containing carboxyl groups. The acidic units are reacted with an imine, as described later, the reaction being carried out with the polymer containing the acid or with acid groups,

   before or during polymerization.

 <Desc / Clms Page number 5>

 



   The acid used to provide the acid units may be any polymerizable monocarboxylic or polycarboxylic acid preferably containing from 3 to 6 carbon atoms. Acrylic acid is preferred, the term "acrylic acid" including acrylic acid, methacrylic acid and similar alpha-substituted acrylic acids. Also usable are maleic acid and fumaric acid, as well as the hemi-esters of these dicarboxylic acids such as, for example, mono-, butyl maleate.

   Other acids, such as crotonic acid, 3-butenoic acid, tiglic acid and itaconic acid and its hemi-esters can also be used, as can various carboxylic acids. long chains containing polymerizable groups. Certain copolymerizable fatty acids, such as dehydrated castor oil acids, etc., can also be used.



   Various alkyleneimines, including substituted alkyleneimines, can be used to modify the acid groups. The preferred alkyleneimines correspond, in general, to the formula
 EMI5.1
 wherein R1, R2, R3, R4 and R5 each denote hydrogen or an alkyl group, such as methyl, ethyl, propyl, etc., containing, for example, up to about 20 carbon atoms; aryl, such as phenyl, etc., alkaryl,. such as tolyl, xylyl, etc. ,, or aralkyl, such as benzyl, phenethyl etc.

   In this formula, R6 denotes hydrogen

 <Desc / Clms Page number 6>

 or a lower alkyl group usually not containing. 'not more than about 6 carbon atoms and n is equal to
0 or 1., @
Groups designated by the formula given above may have substituted radicals of the classes indicated, wherein the substituent groups do not adversely affect the basic nature of the inine in the reaction. The substituents can include, for example, groups, such as cyano, halo, amino, hydroxy, alkoxy, carbalkoxy or nitrile groups.

   The substituted groups may therefore be cyanoalkyl, haloalkyl, aminoalkyl, hydroxyalkyl, alkoxyalkyl, carbalkoxyalkyl or similar substituted derivatives of optional aryl, alkaryl and aralkyl groups.



   Those skilled in the art will understand that compounds containing certain combinations of the above groups cannot be obtained, for example due to certain factors, such as steric hindrance or intramolecular interaction. For this reason, in most of the compounds of the class described, several of the groups designated by R 1 to R represent hydrogen.

   However, the effectiveness of the various imines of the formula given above or not does not depend on the particular nature of any of the substituents, but rather on the imine bond; beneficial results being obtained with interpolymers modified by any of the compounds belonging to the aforementioned class.



   Among the alkyleneimines which can be used in the context of the present invention

 <Desc / Clms Page number 7>

 
 EMI7.1
 ...: .., ...... oa may cite, by way of nonlimiting examples, the following iminea 1.



  Ethyleneimine (aziridine) 1,2-propyleneimme (2-methyl aziridine) 1,3-propyleneimine (izetidine) 1,2-dodeyleneimine (2-decyl aziridine) 1,1-dimethyl ethyleneimine (2,2-dimethyl aziridine) Phenyl ethyleneimine (2-phenyl aziridine) Tolyl ethyleneimine (2- (4-mebethylphenyl) aziridine) Benzyl ethyleneimine (2-phenylmethyl aziridine)
 EMI7.2
 1.2-Diphenyl ethyleneimine (2,3-diphenyl aziridine) Hydroxyethyl ethyleneimine (2- (2 <-hydroxyethyl) aziï'idine) Aminoethyl ethyleneimine (2 - '(2-aminoethyl) aziridine) 2-methyl propyleneimine (3-methyl azetidine) 3-chloropropyl ethyleneimine (2- (3-chloropropyl) aziridine)
 EMI7.3
 p-chlorophenyl ethyleneimine (2 (4-chloroph, nyl) azir, dina) Methoxyethyl ethyleneimine (2- (2-methoxyethyl) aziridine)

   Dodecyl aziridinyl formate (dodecyl 1-aziridinyl oarboxy-, late)
 EMI7.4
 , .Carbethoxyethyl ethyleneimine (2- (2-carbethoxyethyl) aziridine)
N-ethyl ethyleneimine (1-ethyl aziridine) N-butyl ethyleneimine (1-butyl aziridine) N- (2-aminoethyl) ethyleneimine (1- (2-aminoethyl) aziridine) N- (phenethyl) ethyleneimine (1- (2- phenylethyl) aziridine)
 EMI7.5
 N- (2-hydroxyethyl) ethylbneimine (1. (2-hydraxyethylaxir3.dine) N- (cyanoethylÙethylenimine (1-cyanoethyl aziridine) v, N-phdnyl ethyleneimine (1-phenyl aziridine) N-tolyl ethyleneimine (1- (2- methylphenyl) aziridine)
 EMI7.6
 N- (p-chlo, rohenyl)

  ethyleneimine (1- (4 '* ohlorophenyl) aziridine) t

 <Desc / Clms Page number 8>

 
Because of their easy availability and high efficiency, the preferred imines are alkyleneimines and substituted alkyleneimines containing 2 to 4 carbon atoms, and especially ethyleneimine, 1, 2-propyleneimine, and 'N-hydroxyethyl ethyleneimine.



   The reaction with the imine takes place by mixing the imine with the carboxylated material and heating the mixture to moderate temperatures, ie 50-15,000, fine. that higher or lower temperatures can be used, depending on the reaction time desired.



  The imine reacts with the acidic carboxyl groups, but the exact nature of the reaction which takes place under these circumstances and the structure of the product obtained is not known with certainty. In the case of ethyleneimine and 1,2-propyleneimine which are the preferred imines, the reaction involves, at least to some extent, the production of a primary amino group, which is not available. been able to obtain so far in this class of subjects.



  Provided that at least some modification is carried out with the aid of an imine, the improved properties are obtained when all or part of the carboxyl groups present are reacted with the imine. extent of reaction depending on the amount of imine used. It is sufficient that at least about 0.1% by weight of the polymerized carboxylic acid units, relative to the total weight of the interpolymer, is reacted with the imine. @

 <Desc / Clms Page number 9>

 
The reaction with the imine preferably takes place during or after the interpolymerization of the hydroxyalkyl ester, the acid and the other monomers.



   Although the reaction with the imine often takes place after the production of the acid-containing polymer, it has been found that a certain saving of time, without any deterioration in properties, is obtained when the reaction with the imine takes place at the same time as the polymerization reaction. In this embodiment, the imine is added to the polymerization mixture at any time, before the completion of the polymerization reaction. The imine is preferably added after the monomers, but before the polymerization has progressed to any significant extent,
The polymerization reaction itself takes place. otherwise in the usual manner, using heat and / or catalysts, as well as various solvents and techniques.

   In general, a free radical producing catalyst such as cumene hydroperoxide, benzoyl peroxide or a similar peroxygen compound or an azo compound is used. When the polymerization reaction and the reaction with the imine are carried out at the same time, it is preferred to use, as catalyst, azo compounds, in particular alpha, alpha'-azobis- (isobutyronitrile).



   Interpolymers may contain as the hydroxyalkyl ester monomer any such ester, but alkylene glycol monoesters are especially preferred in which the alkylene group contains up to 12 carbon atoms and, in particular, are preferred. in particular, acrylic or methacrylic acid monoesters of ethylene glycol,

 <Desc / Clms Page number 10>

 1,2-propylene glycol, 1,3-propylene glycol and 1,4-butylene glycol. However, polyhydroxyalkyl esters such as 2,3-sihydroxyprophyl acrylate, 6,10-dihydroxyalkyl methacrylate, etc., can also be used.

   Similar esters of other unsaturated acids can also be used, for example, those containing up to about 6 carbon atoms, including mono and diesters of unsaturated dicarboxylic acids, such as maleic acid, l. fumaric acid and itaconic acid (the term "acids" including anhydrides of acids which form anhydrides). Among these esters, there may be mentioned, for example, hydrogenated hydroxyethyl maleate, bis (hydroxypropyl) fumarate, and butyl hydroxyethyl maleate. The use of the unsaturated dicarboxylic acid esters, in whole or in part, in

 <Desc / Clms Page number 11>

 certain compositions provide specific desirable characteristics.



   The remainder of the interpolymer consists of one or more other ethylenic monomers. Preferred classes of monomers are those of alkyl esters of an ethylenically unsaturated arboxylic acid, such as alkyl aarylates or alkyl methacrylates and vinyl aromatic hydrocarbons. It is preferred that at least one alkyl acrylate or methacrylate is present. Among the alkyl acrylates and methacrylates generally used, mention may be made of ethyl, methyl, propyl, butyl, hexyl, ethylhexyl and lauryl acrylates and methacrylates, as well as the acrylates and methacrylates of ethyl, methyl, propyl, butyl, hexyl, ethylhexyl and lauryl. si- esters. milars containing up to about 20 carbon atoms in the alkyl group.

   The vinyl aromatic hydrocarbon, when one is employed, is usually styrene, alpha-alkyl styrene or vinyl toluene. Other monomers can also be employed such as, for example, acrylonitrile, vinyl acetate and similar vinyl esters, aliphatic hydrocarbons such as 1,3-butadiene, other esters such as dibutyl maleate, glycidyl methacrylate and dimethylbenzyl acylate, as well as other oopolymerizable monomers containing, preferably, a CH2-C <.. group.

 <Desc / Clms Page number 12>

 



   The imine-modified interpolymers discussed herein can be used as the sole or film-forming component of the composition, but it is most preferred that they are used with one or more other coreactive resinous components. to form the thermosetting coating composition. The additional film-forming component may be compatible with the hydroxyalkyl ester interpolymer and should be able to react with this interpolymer at elevated temperatures, such as those used for curing coatings, for example at 65.5 ° C. more.



  As additional preferred resin components, there may be mentioned amine-aldehyde type resins and, in some cases, alkyd resins:
Resins of the amine-aldehyde type. are products of condensation of aldehyde with melamine, urea, acetoguanamine or the like. In general, the aldehyde used is formaldehyde, although the products can be obtained with other aldehydes such as acetaldehyde, crotonaldehyde, acrolein, benzaldehyde, furfural etc.

   Although resins obtained from melamine and urea are most common and preferred, condensation products of other amines and amides can also be used, such as those of triazines, diazines, etc. triazoles, guanidines, guanamines and alkyl and aryl derivatives of these compounds, especially alkyl and aryl urea and alkyl and aryl lamines, provided that at least one amino group is present.

   Examples of such compounds include N, N'-

 <Desc / Clms Page number 13>

 
 EMI13.1
 dirw3 ylurea, benzyl urea, dicyandiamide, formoguan ,, iine ,, benzoguanamine, ammeline, 2-chloro-4,6-diani, io-1,3,5-triazine, 6- mdthyl-2,4.-diamino-1., 3,5-triazine, 2-phnyl-4-amino-6.-hydroxy.-1,3,5-tr.axine, 3,5- Sun . otriazole, triaminopyrimidine, 2-mercapto-4,6- '>,> 5. diamiiw-pyrimidine, 2,4,6-trihydrazine-1,3,5-triazine,. 2,, 6-tridthyl.triamino-1,3,5-triazine, 2,4,6-tri-pny.; i.amino-1,3,5-triazine, etc.



   These aldehyde condensation products contain methylol groups or similar alkylol groups which must be etherified in whole or in part by reaction with an alcohol. Any monohydric alcohol can be used for this purpose, including methanol, ethanol, propanol, butanol, pentanol, hexanol, and other alkanols usually containing up to about 12 carbon atoms, as well as benzyl alcohol and other aromatic alcohols, cyclic alcohols such as cyclohexanol; monoethers of glycols, such as cellosolves and carbitols;

     as well as alcohols substituted with halogens or other groups, such as 3chloropropanol. The amine-aldehyde resins are obtained in a well-coordinated manner, using an acidic or basic catalyst and various time and temperature conditions.



   Formaldehyde is often used in the form of a solution in water or alcohol, and the condensation, etherification and polymerization reactions can take place as a result of any of the following. the other or at the same time.



   Alkyd resins are also used in
 EMI13.2
 compositions containing the imine-modified interpolymer. When an alkyd resin is used, this is

 <Desc / Clms Page number 14>

 ordinarily employed in conjunction with an amine-aldehyde resin, although in some cases the inter-polymer and the alkyd resin may be used alone. Alkyd resins obtained from saturated oils or saturated fatty acids are preferred, but It is also possible to use any of the saturated or unsaturated alkyd resins used in the field of coatings.

   So, for example, alkyd resin can be
 EMI14.1
 obtained from polytonctional acids such as acid. phthalic acid, maleic acid, fumaric acid ,, isophthalic acid, succinic acid, trimel.â.it3que acid, adipic acid, azelaic acid, sebacic acid etc.,:
 EMI14.2
 like the anhydrides of these acids. Poly- alcohol. ' functional can be, for example, glycerin, tri-methylolethane, trimethylolpropane, pentaerythritol, '1' .; sorbitol, mannitol, ethylene glycol, diethyl-: - ": â a'cl, 2, 3-butylene glycol and similar polyols .....) t: -
The alkyd resin may or may not be modified by an oil.

   The oil optionally used is preferably coconut oil or other saturated oil, although drying or non-drying oils, such as fish oils, linseed oil, oil. soybeans, etc., can also be used. If desired, the alkyd resin can contain a monobasic acid, such as acid
 EMI14.3
 bensoic, a substituted benzolque acid or a similar monobasic aromatic acid.

   The alkyd resin can also
 EMI14.4
 '.: t.,; 7J polyester. containing adipic acid or a similar acid, as well as various glycols and / or polyols; or it may contain copolymerized monomers, such as alkyl esters of acrylic acid and methacrylic acid

 <Desc / Clms Page number 15>

 acrylonitrile, olefinic hydrocarbons and other such monomers containing a CH2 = C @ group.



   The alkyd resin can be obtained by any of the well known methods used to prepare alkyd resins for coatings. It is desirable that functional groups, such as unreacted hydroxyl groups, remain in the alkyd resin. When the alkyd resin is to be modified with another unsaturated monomer, an unsaturated fatty acid or an ethylenically bonded [alpha], ss acid, such as maleic acid, fumaric acid or l The crotonic acid must be present in the alkyd resin and the esterification and copolymerization reactions can take place simultaneously at different stages, depending on the nature. of the alkyd resin used.

   To achieve maximum compatibility with other constituents of the coating composition, it is often desirable that the alkyd resin be prepared using a relatively large excess of polyol and that the polyol used has the neopentyl structure, as in the case of the polyol used. trimethylolpropane and trimethylolethane.



   Although amine-aldehyde resins and alkyd resins are preferred, other polymers containing functional groups which provide groups suitable for cross-linking with the hydroxyalkyl ester interpolymers are also used with them.

   Among these other polymers, there may be mentioned, for example, the following:

 <Desc / Clms Page number 16>

 (a) Polyepoxides, such as epichlorohydrin-bisphenol A reaction products having epoxide equivalents between about 150 and 1500, such as Epon 828, which has an epoxide equivalent of 175-210 and a molecular weight from 350-400, or Epon 1001 which has an epoxide equivalent of 450-525 and a molecular weight of 900, to 1000; (b) epoxy esters, such as esters of unsaturated fatty acids and of glycidyl ethers of bisphenols, for example esters of linseed oil or soybean oil. of Epon 828 or a similar epolyepoxide;

   (c) vinyl halide polymers, such as copolymers of polyvinyl chloride and vinyl acetate, eg, vinylite VAGH which contains 91% vinyl chloride, 3% vinyl acetate and 2.3% hydroxyl group or vinylite VMCH which contains 86% vinyl chloride, 13% vinyl acetate and 1% interpolymerized dibasic ali; (d) cellulosic polymers, such as nitrocellulose, cellulose ether, cellulose acetate and the various cellulose acetate butyrates, interesting cellulose acetate butyrate containing 20.5% acetyl groups , 26.5% of butyryl groups and 2.5% of hydroxyl groups;

   (e) polysiloxanes, such as dimethyltriphenyltrimethoxytrisiloxane or the product called “Dox-Corning Z-6018” which is a phenyl siloxane resin comprising approximately 4 hydroxyl groups per molecule and whose average molecular weight is approximately 1600.



   (f) phenolic resins, such as the alkali catalyzed condensation product of p-tert.-butyl phenol and excess formaldehyde, and other phenol-formaldehyde resins.

 <Desc / Clms Page number 17>

 
 EMI17.1
 



  The proportions of each of the resin components in the compositions in question are not critical, but in general the compositions should contain e. Iron 90 to 30% of the hydroxyalkyl ester interpolymer and about 10 to 70% of the coreactive resin component.



  Preferred alters contain about 75-40% hydroxyalkyl ester interpolymer, about 25-60% amine-aldehyde resins and about 0-35% alkyd resin.



  These weightings are based on the total weight of the hydroxyalkyl ester inter-polyoer and resin or resins capable of reacting with that interpolymer. Note that all or part of the interpolymer is est. hydroxyalkyl can be modified by reaction with the imine; thus, only the part used to disperse the pigment can be changed.



   The interpolymers and mixtures described above are used as a film-forming component of pigmented or unpigmented coating compositions, these compositions possibly containing any of the various pigments used with materials, as well as solvents, plasticizers, fillers, agents. addition materials, etc. They are used, for example, in enamels or pigmented lacquers for motor vehicles, including pastel and polychrome enamels, to which metallic pigments and colored pigments, as well as various plasticizers and additives are commonly used. incorporated.

   As indicated above, a particular advantage of these compositions is the ease with which pigments, such as carbon black, can be ground or dispersed in these compositions; these also provide partial coatings

 <Desc / Clms Page number 18>

 particularly interesting and attractive with metallic pigments, as used to obtain polychrome clothes.



   The coating compositions are applied by conventional techniques, preferably by spraying, and are cured in the usual manner, usually subjecting them to baking at temperatures.
 EMI18.1
 ', S from 65 to .5f? G for 10 to 40 minutes. These compositions can be applied, with favorable results, to any solid support.



  Thus, they can be applied on glass, roof, hardboard, plastics and various metals, such as steel, treated steels, aluminum, etc.



  The compositions containing the modified interpolymers disclosed herein are particularly useful when applied over basecoats, such as those used on motor vehicle bodies and the like. These base coats are generally thermosetting or curable in another material, that is to say crosslinkable,
The following exemptas further illustrate the invention, without being limited thereto. Parts and percentages referred to in these examples and elsewhere herein are by weight and are based on non-volatile solids content, unless otherwise noted.

 <Desc / Clms Page number 19>

 



     @ EXAMPLE
The following ingredients were slowly introduced into a glass reaction vessel containing a refluxed mixture of. 1096 parts xylene and 144 parts.
 EMI19.1
 J'f rtles of butanol!
 EMI19.2
 
<tb> Parts <SEP> in <SEP> .weight
<tb>
<tb> <SEP> butyl <SEP> methacrylate <SEP> 510
<tb>
<tb> methacrylate <SEP> of <SEP> mthyle <SEP> 465
<tb>
<tb> <SEP> ethyl acrylate <SEP> 345 '<SEP>' <SEP>
<tb>
<tb> <SEP> 2-hydroxypropyl <SEP> methadrylate <SEP> 150
<tb>
<tb> <SEP> methacrylic acid <SEP> 30
<tb>
<tb> <SEP> Benzoyl <SEP> <SEP> <SEP> 15
<tb>
 
After the addition which took 2.5 hours, the mixture was further heated under reflux for 6 hours, a solution of 3,

  75 parts of benzoyl peroxide in 100 parts of xylene being added after the 2nd and 4th hours. The obtained product (3000 parts at 50% solids) was mixed with 5 parts of 1,2-propyleneimine and heated under reflux for 3 hours. The product had an acid number of 6.92% and a Gardner-Holdt viscosity of W-.



   This product was pigmented by mixing 188 parts of the imine modified product, 60 parts of carbon black, 94 parts of butanol, 77 parts of toluene and 1.8 parts of p-phenylenediamine. After milling this mixture for 72 hours in a steel ball mill, 144 parts of the imine modified polymer solution and 29 parts of butanol were added. Grinding was continued for 2 1/2 hours, making the same addition after the first and second hour.



   The resulting dispersion contained 6.4% by weight pigment and 33% by weight vehicle solids.



  A black enamel was prepared by mixing 78 parts of dispersion with 68.4 parts of the pre-imine modified product.

 <Desc / Clms Page number 20>

 cited and 80 parts of butylated melamine-formaldehyde resin (50% solid, obtained from 5.5 moles of formaldehyde and 6 moles of butanol per mole of melanin).



   The films of the enamel obtained applied to steel plates and baked for 30 minutes at 121 0 had very advantageous properties, in particular.
 EMI20.1
 excellent jet black tint. When compared to re ', ts obtained in the same way, from inter-polymers, nt the same composition, but not modified by an imine, the aforementioned' -. Ridges'. much better. Ai, lii, the appearance of coatings which do not contain imine ne i.ilī, nd do not meet the criteria required for automobir bodies, 1. while the imine modified coating gives Bati ;; ... "ction in this regard.



    EXAMPLE 2.



   The procedure was as in Example 1 except that the reaction with the imine was carried out using 3750 parts of polymer solution and 4.7 parts of ethylene imine, so as to obtain a product having an acid number of 6.42 and a Gardner-Holdt viscosity of W. The enamel obtained with this product had substantially the same properties as that prepared in Example 1,
EXAMPLE 3.



   In a glass reaction vessel, 404 parts of xylene and 175 parts of butanol were placed. This mixture was heated to reflux and the following ingredients were added to it within 3 hours!

 <Desc / Clms Page number 21>

 
 EMI21.1
 
<tb> Parts <SEP> in <SEP> weight
<tb>
<tb>
<tb>
<tb> styrene <SEP> 545.
<tb>
<tb>
<tb>
<tb>
<tb>



  , <SEP> <SEP> 2-ethylhexyl <SEP> acrylate <SEP> 545.
<tb>
<tb>
<tb>
<tb>
<tb> <SEP> butyl <SEP> methacrylate <SEP>, 182
<tb>
<tb>
<tb>
<tb>
<tb> methacrylate <SEP> of <SEP> methyl <SEP> 328
<tb>
<tb>
<tb>
<tb>
<tb> hydroxypropyl methacrylate <SEP>
<tb>
<tb> in <SEP> solution. * <SEP> 182
<tb>
<tb>
<tb>
<tb>
<tb> hydroxyethyl <SEP> methacrylate
<tb>
<tb> in <SEP> solution <SEP> ** <SEP> 244
<tb>
<tb>
<tb>
<tb>
<tb> acid <SEP> acrylic <SEP> 69
<tb>
<tb>
<tb>
<tb>
<tb> tert.-dodecyl <SEP> mercamtant <SEP> 36.4
<tb>
<tb>
<tb>
<tb>
<tb> alpha, <SEP> alpha'-azobis-
<tb>
<tb>
<tb> (isobutyronitrile) <SEP> 9.1
<tb>
<tb>
<tb>
<tb> xylene <SEP> 360
<tb>
 * 40% solution in xylene containing about 5,

  5% methacrylic acid ** 30% solution in xylene containing about 2% methacrylic acid.



   After the addition, the mixture was cooled to 120 0 and 30.3 parts of ethylene was added thereto. It was again heated to reflux while slowly adding a solution of 5.47 parts of azobis (isobutyronitrile) in 205 parts of xylene. After 3 hours the addition of the catalyst was complete and, after further heating under reflux for 1 hour, 295 parts of xylene were added and the mixture cooled. The product had a solids content of 52%, an acid number of 5.25 and a Gardner-Holdt viscosity of T +.



   A pastel blue enamel was prepared by pigmenting a mixture of 60 parts of the above product and 40 parts of melamine-formaldephyde resin (relative proportions

 <Desc / Clms Page number 22>

 based on solids). Melamine-formaldehyde resin was a butylated condensation product of melamine and formaldehyde with a molar ratio of 5.5 moles of formaldehyde and 6 moles of butanol per mole of melamine. The pigment content of the enamel was 21%, based on the vehicle solids, and this concentration was reduced, using xylene to a viscosity (Ford Cup # 4) of 17 seconds.

   The reduced product had a total non-volatile solids content of 43.6%.



   To the enamel were added 1.5% (based on the total weight) of a 7.5% xylenic solution of mono- and di-butylic acid orthophosphates and a 0.05 mm film. was applied to a steel plate provided with a primer. The plate was then baked for 30 minutes at 121 C, then cooled, after which half of the coating was subjected to heat. wet sandblasting. The plate was then covered with a layer of the enamel, to which 1% of a 75% xylenic solution of the above-mentioned orthophosphate had been added. After baking for 20 minutes at 820, the plate was cooled and scratched over its entire surface.

   Pressure sensitive adhesive tape was applied firmly to the scratched portion and then peeled off in a plane substantially parallel to the plate. The coating did not come off in any part indicating that its adhesion was excellent.

 <Desc / Clms Page number 23>

 



    EXAMPLE 4.



   The procedure was as in Example 3, except that a weight ratio of 70 parts of imine modified interplyser and 30 parts of melanin-formaldehyde resin was used. The plates obtained exhibited at. knots: excellent grip.



   EXAMPLE 5,
The procedure was as in Example 3, using an interpolymer modified with an imine obtained using the following mixture:
 EMI23.1
 
<tb> Parts <SEP> in <SEP> weight
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> styrene <SEP> 728
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> <SEP> 2-ethylhexyl <SEP> acrylate <SEP> 545
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> methacrylate <SEP> of <SEP> methyl <SEP> 218
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> <SEP> butyl <SEP> methacrylate <SEP> 127
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> hydroxypro methacrylate <SEP>
<tb>
<tb>
<tb>
<tb>
<tb> pyle <SEP> en <SEP> solution <SEP> * <SEP> 182
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> hydroxyethyl <SEP> methacrylate
<tb>
<tb>
<tb>
<tb> in <SEP> solution <SEP> * <SEP> 242
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> acid <SEP>

  methacrylic '<SEP> 54.4
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> tert. <SEP> -dodecyl <SEP> mercaptan <SEP> - <SEP> 27.3
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> azobisisobutyronitrile <SEP> 9.1
<tb>
 * as in example 3.



   Instead of the ethyleneimine used in Example 3, 17.2 parts of 2-hydroxyethyl ethylenimine were added during the polymerization. The obtained product had a solids content of 51.3%, an acid number of 7.95, and a Gardner-Holdt viscosity of R-S.

   This product was pigmented with carbon black, grinding the following ingredients in a steel ball mill for 72 hours:

 <Desc / Clms Page number 24>

 
 EMI24.1
 
<tb>, Parts <SEP> in <SEP> weight /
<tb>
<tb> product <SEP> aforementioned <SEP> (51.4 <SEP>%
<tb>
<tb> <SEP> solids) <SEP> 312
<tb>
<tb> Black <SEP> of <SEP> carbon <SEP> 30
<tb>
<tb>
<tb> butanol <SEP> '<SEP> 71
<tb>
<tb> toluene <SEP> 36
<tb>
<tb>
<tb> xylene <SEP> ^ '<SEP>' <SEP> 151
<tb>
 
The resulting pigment dispersion was used in a coating composition together with a. melamine-formaldehyde resin, as described in Example 1. The product exhibited comparable valuable properties.



   EXAMPLE 6.



   The procedure was as in Example 1 to prepare an interpolymer from the following mixture:
 EMI24.2
 
<tb> Parts <SEP> in <SEP> weight:
<tb>
<tb> <SEP> 2-ethylhexyl <SEP> acrylate <SEP> 418
<tb>
<tb> methacrylate <SEP> of <SEP> methyl <SEP> 674
<tb>
<tb> butyl <SEP> <SEP> methacrylate <SEP> 545
<tb>
<tb> hydrxoypropyl methacrylate <SEP> <SEP> in <SEP> solution <SEP> * <SEP> 182
<tb>
<tb> hydroxyethyl methacrylate <SEP> <SEP> 73
<tb>
<tb> <SEP> methacrylic acid '<SEP> 34
<tb>
<tb> azobis <SEP> (isobutyronitrile) <SEP> 9.1
<tb>
<tb> tert.-dodecyl <SEP> mercaptan <SEP> 34
<tb>
 * As in example 3.



   The resulting interpolymer had an acid number of 8.18 and a Gardner-Holdt viscosity of L-. It was reacted with propylene imine, as in ltexem. ple 1, so as to form a modified polymer which has been -applied ,, in the form of a layer, on a steel plate,

 <Desc / Clms Page number 25>

 
After curing as described above, pigmented and unpigmented coatings having excellent properties were obtained.



    EXAMPLE 7.



     The pigment dispersion of Example 5 in an enamel was used together with an acrylic interpolymer, an amine-aldehyde resin and an alkyd resin.



   The acrylic interpolymer was obtained by operating in the manner described in Example 1, using the following ingredients:
 EMI25.1
 
<tb> Parts <SEP> in <SEP> weight
<tb>
<tb> styrene <SEP> 1350
<tb>
<tb> <SEP> 2-ethylhexyl <SEP> acrylate <SEP> 1350
<tb>
<tb> methacrylate <SEP> of <SEP> methyl <SEP> 810
<tb> butyl <SEP> <SEP> methacrylate <SEP> 545
<tb>
<tb>
<tb> hydroxypropyl methacrylate <SEP>
<tb> in <SEP> solution <SEP> * <SEP> 180
<tb>
<tb> hydroxyethyl <SEP> methacrylate
<tb> in <SEP> solution <SEP> * <SEP> '<SEP> 180
<tb>
 
 EMI25.2
 aé1aecmthacrylic.

   70 * as in example 3
The amine-aldehyde resin was a butylated melamine-formaldehyde resin obtained from 55 moles of formaldehyde and 6 moles of butanol per mole of melamine, and the alkyd resin was a trimethylolethane-phthalic hydride resin containing 38.8% phthalic anhydride dt 35.2% coconut fatty acids. The composition of the enamel was as follows:

 <Desc / Clms Page number 26>

 
 EMI26.1
 ', Parties, m¯pqidā.

     '' j = '
 EMI26.2
 
<tb> Solution <SEP> Pigment <SEP> Material
<tb>
<tb>
<tb>
<tb>
<tb> solid
<tb>
 
 EMI26.3
 '¯¯¯¯%, do S'. dispe: reion of pig- 100,, ";, '"' ',>. é. pig- ment: 100.0. 26
 EMI26.4
 
<tb> interpolymer
<tb>
<tb> acrylic <SEP> 43.0 <SEP> 21.5 <SEP> @
<tb>
<tb> resin <SEP> amine-alde-
<tb>
<tb> hyde <SEP>. <SEP> 57.0 <SEP> 19.0
<tb>
<tb>
<tb> resin <SEP> alkyd <SEP> 29.3 <SEP> 28.5
<tb>
 
This enamel applied to steel plates and baked in the manner described above exhibited an excellent jet black appearance and a. Well. shiny,
 EMI26.5
 (brilliant at 20's, ¯95). Other compositions belonging to '¯ 1 "to the described class have given comparable results.



  Thus, the interpolymers of the examples given above can be replaced by corresponding interpolymers modified with other alkylene imines such as those mentioned above. Likewise, the monomers used in the interpolymers shown are those which give, as has been seen, interesting overall properties for certain applications, for example for the coating of automobile bodies, but interpolymers obtained from other monomer systems can be used and give good products with excellent properties. An example of such an interpolymer is as follows:
EXAMPLE 8.



    The following ingredients were added to a refluxed mixture of 675 parts xylene and 175 parts butanol in a reaction vessel over 3 hours;

 <Desc / Clms Page number 27>

 
 EMI27.1
 
<tb> '<SEP> Parts <SEP> in <SEP> weight
<tb>
<tb>
<tb> <SEP> butyl <SEP> and <SEP> hydroxy- fumarate <SEP>
<tb>
<tb> ethyl <SEP> 455
<tb>
<tb>
<tb>
<tb>
<tb> styrene <SEP> 545
<tb>
<tb>
<tb>
<tb> <SEP> 2-ethylhexyl <SEP> acrylate <SEP> 382
<tb>
<tb>
<tb>
<tb>
<tb> <SEP> methacrylic acid <SEP> 40
<tb>
<tb>
<tb>
<tb> <SEP> methyl <SEP> methacrylate <SEP> 400
<tb>
 
 EMI27.2
 azobis (isobutyronitrile) gel
 EMI27.3
 
<tb> tert.-dodecyl <SEP> mercaptan <SEP> 4.5
<tb>
<tb> xylene <SEP> 360
<tb>
 
After this addition,

   A solution of 1.82 part of azobis (isobutyro-nitrile) in 69 parts of xylene was added over 15 minutes, after which refluxing was continued for 6 hours, adding the same amounts of same catalyst after the second and after the fourth hour. Then 295 parts of xylene were added.



  The product had an acid number of 7.3, a solids content of 50.2% and a Gardner-Holdt viscosity of V-. Comparable results were obtained with the product when it was used instead of the hydroxy alkyl ester interpolymer of the previous examples (especially example 1).



   Another embodiment of the invention relates to the addition of a different polymer to the hydroxyalkyl ester interpolymer, which polymer contains the vinyl polymerized imine modified carboxylic acid groups. Such a polymer can be an acrylic resin, for example a methyl methacrylate polymer containing interpolymerized acrylic or methacrylic acid which has reacted with an ethylene imine; an alkyd resin, such as

 <Desc / Clms Page number 28>

 those mentioned above, in which the residual carboxyl groups are reacted with ethylene imine or other alkylene imine;

   or an interpolymer obtained from any ethylenic monomer system comprising an interpolymerized carboxylic acid as described above. Examples of suitable monomers include styrene, vinyl toluene and other vinyl aromatic hydrocarbons; esters of organic or inorganic acids, such as vinyl acetate, dimethyl maleate, vinyl chloride, etc., as well as the various monomers mentioned above in connection with the interpolymer hydroxyalkyl ester.

   The only condition is that the added polymer is reasonably compatible with the other constituents. ,
As an example of this embodiment, the composition of Example 1 is prepared with the same interpolymer of hydroxy alkyl ester, but without reaction with ethylene imine. To 60 parts of this interpolymer are added 10 parts of an interpolymer of 40% styrene, 40% ethyl acrylate, 15% butyl metha- erylate and 5% methacrylic acid. , the acid groups having been reacted with ethyleneimine. This mixture is then mixed with 40 parts of melamine-formaldehyde resin, as in Example 1.

   When applied as a layer on steel plates and baked for 30 minutes at a temperature of 121 ° C, this composition gives a coating exhibiting valuable properties.

 <Desc / Clms Page number 29>

      



   Various other co-reactive resins can be used in place of or in addition to those given by way of example. Thus, urea-formaldehyde resins can be used, for example a butylated urea-formaldehyde condensation product obtained from 2.2 moles of formaldehyde and 1.8 moles of butanol per mole of urea; hexakis (methoxymethyl) melamine; tetrakis (methoxymethyl) - benzoguanamine; alkyd resins, such as that obtained from 966 parts of coconut fatty acid, 1006 parts of trimethylolethane, 74 parts of p-t-butyl benzoic acid and 1187 parts of phthalic anhydride.

   Another useful alkyd resin is that obtained from 793 parts of 1,3-butanediol, 448 parts of trimethylol-ithane, 834 parts of adipic acid and 573 parts of phthalic anhydride.

   Such an alkyd resin can be used, for example, in the compositions of Examples 1 or 2, in an amount of 20% of the total vehicle, or it can replace half of the melamine-formaldehyde resin, in the compositions. of these examples. @
It is obvious that the invention is not limited to the details described above and that numerous modifications can be made to these details without departing from the scope of the invention.

 

Claims (1)

CLAIMS. 1.- Thermosetting coating composition, characterized in that it contains as the main film constituent an interpolymer (a) of about 2 mole% @ to 25 mole% of a hydroxyalkyl ester of a carboxylic acid ethylenically linked, (b) from about 0.1 mole% to 20 mole% ethylenically linked carboxylic acid and (c) at least one other co-polymerizable ethylenically linked monomer, which composition contains at least 0 , 1% by weight of polymerized vinyl carboxylic acid units, which have been reacted with an alkylene imine. 2. A composition according to claim 1, characterized in that the alkyleneimine corresponds to the formula: EMI30.1 wherein R1, R2, R3, R4 and R5 each denote hydrogen or an alkyl, aryl, alkaryl or aralkyl group, R6 denote hydrogen or a lower alkyl group and n. is equal to 0 or 1. 3.- Coating composition according to revendis cation 2, characterized in that said other monomer is chosen from alkyl esters of ethylenically bonded carboxylic acids and vinyl aromatic hydrocarbons. 4. A composition according to claim 1, characterized in that the polymerized vinyl carboxylic acid units are contained in a polymer which is present. <Desc / Clms Page number 31> in addition to the aforementioned interpolymer. 5. A coating composition according to claim 1, characterized in that said carboxylic acid units consist of an ethylenically bonded acid containing 3 to 6 carbon atoms and 1 to 2 carbon xyl groups. 6. A coating composition according to claim 5 characterized in that the imine is an alkyleneimine containing 2 to 4 carbon atoms. 7. The coating composition according to claim 1 characterized in that a resin compatible with the interpolymer and capable of reacting therewith at elevated temperatures is used as an additional film forming component. 8. A coating composition according to claim 7, characterized in that the additional film-forming component is an amine-aldehyde resin modified by. an alcohol, 9.- Coating composition according to claim 6, characterized in that the amine-aldehyde resin is a melamine-formaldehyde resin modified with butanol. 10.- Coating composition according to claim 7, characterized in. in that an alcohol-modified amine-aldehyde resin and an alkyd resin are used together. additional film-forming constituents. 11. A coating composition according to claim 10, characterized in that the amine-aldehyde resin is a melamine-formaldehyde resin and the alkyd resin is a saturated alkyd resin containing unreacted hydroxyl groups. <Desc / Clms Page number 32> 12.- Thermosetting coating composition, characterized in that it contains as the main constituent of a film, an interpolymer (a) from about 2 mole% to 25 mole% of a hydroxyalkyl ester of a carbon acid. ethylenically linked xyl, (b) from about 0.1 mole% to, @ 20 mole% ethylenically linked carboxylic acid and (c) at least one other copolymerizable ethylenically linked monomer, with said ester and with said acid, said interpolymer having at least about 0.1% by weight of those acidic carboxyl groups which have reacted with an alkyleneimine: ' 13. Interpolymer according to claim 12, characterized in that the unsaturated carboxylic acid contains 3 to 6 carbon atoms and 1 or 2 carboxyl groups. 14. - Interpolymer according to claim 12, characterized in that the other ethylenically bonded monomer is selected from alkyl esters of ethylenically bonded carboxylic acids and vinylaromatic hydrocarbons. 15.- Interpolymer (a) of about 2 mole% to 25 mole% of hydroxyalkyl methacrylate, in which the hydroxyalkyl group contains 2 or 3 carbon atoms, (b) from about 0.1 mole% to 20 mole% of an acrylic acid, and (c) of at least one other copolymerizable monomer chosen from alkyl acrylates, alkyl methacrylates and, @ vinyl aromatic hydrocarbons, at least 0.1% by weight approximately of the vinylpolymerized carboxylic units det interpolymide which have reacted with an alkyleneimine. <Desc / Clms Page number 33> 16, - Interpolymer according to claim 15; characterized in that the alkylenimine is chosen from t ethyleneimine, 1,2-propyleneimine and N-hydroxyethyl ethyleneimine. 17.- Article consisting of a support or solid substrate carrying an adherent layer, of the coating composition according to any one of claims 1 to 11. 18. An article consisting of a solid support or substrate carrying an adherent layer of a coating composition of which the film-forming component is constituted by an interpolymer according to any one of claims 12 to 16.