CA1282414C - Method of making organic amines containing hydroxyalkyl carbamate groups - Google Patents

Abstract

ORGANIC AMINES CONTAINING HYDROXYALKYL
CARBAMATE GROUPS AND METHOD OF MAKING THE SAME
ABSTRACT

Novel compounds comprise a secondary amine containing one or more hydroxyalkyl carbamate groups. The compounds are obtained by reaction of a cyclic carbonate such as ethylene or propylene carbonate with a primary amine group of a multi-functional amine containing at least one primary amine group and at least one secondary amine group which is inhibited from reacting with the carbonate. The secondary amine groups, by surviving the reaction with the cyclic carbonate, remain free to react with functional sites on suitable backbone polymers to anchor the hydroxyalkyl car-bamate groups thereon. These polymers may then be self-cross-linked through hydroxyalkyl carbamate groups. In addition, the compounds of the invention can self-condense to form coatings which are resistant to organic solvents.

Description

~8~414 BACKGROUND OF THE IN~ENTION
The present invention concerns novel hydroxyalkyl carbamates having one or more secondary amine groups thereon and methods of making the same.
The reaction of propylene carbonate with primary and secondary amines to produce corresponding 2-hydroxypropyl carbamates is known in the art (Comp.rend, 1142, 1954). Similar reactions of ethylene carbonate are exemplified by the article, ~The Preparation of Polymeric and Cyclic Urethans and Ureas from Ethylene Carbonate and Amines" by Elizabeth Dyer and Harvey Scott, J.A.C.S. (1956) pp. 672 - 675. See also the report "Polyurethane elastomers obtained without the use of diisocyanates" by L. Ya.
Rappoport, G.N. Petrov, I.I. Trostyanskaya and O.P. Gavrilova in International Polvmer Science and Technoloav, 8, No. 1, 1981. The Dyer-Scott reference discloses that polyurethanes might be prepared from 2-(hydroxyethyl)-carbamate by elimination of ethylene glycol, thereby avoiding the need for using diisocyanates. The Rappoport et al paper discloses generally the reaction of cyclic carbonates with amines to form polyurethane elastomers. Thus, the prior art shows an awareness that amines react with e.g., propylene carbonate, to yield the corresponding hydroxyalkyl carbamates. The Journal of Polvmer Science, Vol. 7, 899 916 (1969), in an article entitled "New Method for PreParina Saturated and Unsaturated Ali~hatic Polvurethanes" by Y. Mizake, S. Ozaki and Y. Hirata, at pages 899 - 915, discloses alternate routes to saturated and unsaturated polyurethanes, including polycondensation reaction of glycol bis(chloroformate~ with 't ~.
~3 ~^ -~X8~414 diamine.
An article by Richard D. Cowell entitled:
"Thermoplastic Polyurethane Elastomers: Chemistry Properties and Processing for the 80's" in the Journal of Elastomers and Plastics, Vol. 14, (October, 1982) pages 195 - 203, discloses the preparation of bis(2-hydroxyethyl) carbamates by reaction of diamines with ethylene carbonate followed by a catalyzed transesterification reaction with a glycol or macroglycol. The two types diamines were used, 1,4 cyclohexane -bis- (methyl-amine) and a product sold under the trademark Jeffamine D2000, comprising a diamine with a polyoxypropylene backbone.
SUMMARY OF THE INVENTION
The present invention provides a process for preparing a hydroxyalkyl carbamate-containing amine of the formula R-NHc-o-cH(7H)ncHoH

wherein each of R1, R2 and R3 is independently H, C1 to C20 alkyl, C3 to C8 cycloalkyl, C3 to C8 aryl, C1 to C8-alkyl-C3 - C8-aryl, or a corresponding alkyl, cycloalkyl, aryl or alkaryl group in which one or more of the respective carbon atoms has been substi~uted by one or more heteroatoms, wherein R-NH is selected from a group consisting of RC~-(NH-Rd)n2-NH Re' 12a wherein n2 is O to 5 and each of Rc,, Rd and Re, is independently C2 to C6 hydrocarbyl and at least one of Rc, and Re, comprises the NH group attached to the R radical;

B

1~8Z4~4 .

HO-CH-CH-O-C-NH-(CH2)X-A (CH2)X 8a R2 Rl O
wherein A is [NH(CH2)x]nNH, n is O to lO, each x is independently 2 to 6 and each of R1 and R2 are as defined above;
Rm~NH~(CH2)y~NH~ 9a wherein y is 2 or 3 and Rm has the same definition as R1, R2 or R3 as defined above with the proviso that it does not represent hydrogen;
NH-R6 ~ R4 10a wherein each of R4 and R6 is independently H or C1 to C4 alkyl and each of R5 and R7 is independently C1 to C4 alkyl;
or o CH-C-NH-R -NHR
¦ O lla CH-C-NH-R -NHR

wherein each R8 is independently a C2 to C6 alkylene moiety, at least one Rga represents a bond and the remaining R9a radicals represent hydrogen or -C-O-CH-CH-OH
il l I

wherein R1 and R2 are as defined above which process comprises reacting a 5- or 6-membered ring 2a B

1~824~4 cyclic carbonate with a multi-functional amine selected from the group consisting of:
ta) RC-(NH-Rd)n2 NH Re 12b wherein n2 is 0 to 5 and each of Rc, Rd and Re is independently C2 to C6 hydrocarbyl and at least one of Rc and Re contains a primary amine group;

(b) Ho-cH-cH-o-lc-NH-(cH2)x-A-(cH2)x-NH2 8b R2 Rl O
wherein A, n, x and each of R1 and R2 are as defined above;
( c ) Rm-NH-(CH2)y~NH2 9b wherein y and Rm are as defined above;
(d) 10b R7 ~l 5 wherein R4, R5, R6 and R7 are each as defined above;

2b B

1~8Z4~4 or (e) o CH-C-NH-R8-NHRg llb ~0~
CH-C-NH-R8-NHRg wherein each R8 is independently a C2 to C6 alkylene moiety, at least one Rg represents hydrogen and the remaining Rg radicals represent hydrogen or -C-O-CH-CH-OH
Il I I
Rl R2 wherein R1 and R2 are as defined above.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Generally, compounds of the present invention are made by reacting one or more amines and cycli~ carbonates as deæcribed above to yield compounds having the formula:
(1) R-NH-C-O-CH-(CH)n-CH-OH

wherein R is an organic moiety having at least one unreacted secondary amine group, each of R1, R2 and R3 is independently H or a C1 to C20 alkyl, cycloalkyl or alkyl aromatic moiety or any such moiety containing, in addition to at least one carbon atom, one or more heteroatoms, and n is O or 1. R may also contain one or more heteroatoms. Such moieties containing one or more heteroatoms include, for example, those containing ether groups, thio groups and organo-silicon moieties.
The cyclic carbonate to be reacted with the multi-~ ,:

~Z824~4 functional amine may comprise any suitable cyclic carbonate, including biscarbonates, which is reactive with one or more of the primary amine groups of a multi-functional amine. Generally, five-member ring organic carbonates are preferred as compared to six-member ring organic carbonates, the latter being relatively more expensive and difficult to prepare. Accordingly, a preferred cyclic carbonate utilizable in the present lnventlon has the formula:

R R
la Ib CH CH
O O
C

B 2d 1~8~414 wherein R8 and Rb may be the same or different, and each may comprise H, or a C
to C8 aliphatic, cycloaliphatic, aromatic or heterocyclic compound. Ethylene carbonate (dioxolane-2-one), both Ra and Rb = H, and propylene carbonate (4-methyldioxolane-2-one), Ra = H and Rb = CH3, are preferred reactants.
The multi-functional amine utilized in the invention contains at least one secondary amine group which is hindered with respect to reacting with the cyclic carbonate and at least one primary amine group. As used herein and in the claims, (a) !'multi-functional amine" means an amine containing at least one primary and at least one hindered secondary amine group; and (b) "hindered sécondary amine group" means a secondary amine group which is inhibited, sterically, electronically or otherwise, with respect to reacting with the cyclic carbonate under conditions at which the primary amine group will react. It has been discovered that, suprisingly, the well known reactivity of primary and secondary amines with cyclic carbonates is highly selective to the primar group for certain multi-functional amines. Stated otherwise, it has been found that certain multi-functional smines have secondary amine groups which are sterically or otherwise inhibited from reacting with a cyclic carbonate, and yet are reactive with, for example, epoxy groups or other functional groups available on backbone polymers.
Thus, hindered secondary amine groups contained in multi-functional amines utilizable in accordance with the present invention enable the formation, with one or more cyclic carbonates, of hydroxyalkyl carbamates in which secondary amine groups remain unre-acted and available to react with epoxy or other active groups. This enables thecompositions of the invention to effectively serve as a means of anchoring hydroxyalkyl carbamate groups by reaction of the compositions with epoxy or other active groups on backbone polymers. For example, when ethylene and propylene carbonates were reacted with diethylenetriamine, they reacted selectively with the primary amine groups of the triamine to form carbamate groups while leaving the secondary amine groups unreacted. Such secondary amine groups can then be reacted with, for example, epoxy groups on backbone polymers, without affecting the carbamate groups.
Further, the compounds of the present invention can be used to prepare polymers containing hydroxyalkyl carbamate groups which can self-cross-link to yield thermoset polyurethanes suitable for a number of applications in the areas of coatings. The self-cross-linking reaction may be base catalyzed or tin-catalyzed, which offers signifi-cant advantages over prior amino resin systems which require acid catalyzation. Thus, the present invention enables the utilization of a system which is free of formaldehyde and in which cure inhibition in the presence of hindered amine ultraviolet stabilizers is avoided.

-4- ~Z82414 ~.
Before discussing in detail the preparation of the hydroxyalkyl carbamate_ containing compounds of the present invention, the use thereof may be illustrated as follows. The hydroxyalkyl carbamate-containing compounds may be rescted with anysuitable ~Ibackbone~ polymer contsining active groups, such as, for example, epoxy groups, in which case the reaction may be represented ss ~h-C~-CH2 ~ HN~ i ~ Rh CHCH2N~R

where Rh is a fragment of an epoxy-containing resin and Ri and R3 are fragments of the hydroxyalkyl csrbamste-containing smine or polyamine compounds oI' the invenffon.
The reaction usually occurs st room or slightly elevsted temperatures and is often exothermic. The reaction may be performed without a solvent, otherwise aproffc or alcohol solvents may be used. Any of numerous types of backbone polymers hsving ~any of a variety of resctive functional groups thereon may also be used, ss described in more detail below. For example, a typical polymer having anchored thereon oneor more of the compositions of the invention may have the formulQ

(4) 1Ol ~h~ ICHCH2N (CH2CH2NHCO ICHCH20H) 2 ] n The resultant polymer, upon heating and, optionally, in the presence of a suitable cross-linking catalyst, will cross-link through one or more mechanisms, ss fo11ows:
by cross-linking through bsckbone hydroxyl groups, e.g., (S) O CH
R -NHC-O- CHCH20H ~ HO-Rh .heat O CH
Il 1 3 Rh-NHC-O-Rh ~ HOCHCH20H;

1;~82414 by cross-linking through self~ondensation, e.g., O CH
(6) 2 R NHC O IHCH OH ~ ~ t h 2 heat Il I
Rh-NHC-O-fHCH201 NH^Rh + HOCHCH20H ; and by cross-linking through backbone amine groups, e.g., Rh-NH~--~CH2H + Rk-NH-Rh cat >

Rh NH ~ Rh ~ HOCHCH 2 0H

wherein Rk is hydrogen or a fragment of the backbone polymer.
The compounds of the present invention, in addition to having utility as interme-diates in the preparation of self-cross-linkable polymers, find utility in their ability to be self-condensed in the absence of backbone polymers to form coherent films which, although but poorly resistant to water, display good resistance to organic solvents.
A wide range of multi-functional amines are utilizable in the present invention to react with the cyclic carbonate inasmuch as, as stated above, it is necessary only that the multi-functional smine contain at least one primary and one hindered secondary amine. For example, one class of multi-functional amines utilizable in the present invention may be represented by the formula:

RC-(NH-Rd)n2-NH Re wherein n2 is O to 5, and each of Rc, Rd and Re is independently a straight chain or brsnched hydrocarbon fragment having 2 to 6 carbon atoms each and at least one of Rc and Re contains a primary amine group.
The formulas of suitable classes of amines may be derived simply by replacing with -NH2 the hydroxyalkyl csrbamate moieties of the compounds set out in formulss (8) to (11) below.

,~J

1~8Z414 (8) HO- ICH- ~CH-O-~j-NH- tCHz)x A (CH2)X ~ ~ R

wherein A is [NH (CH2)"1 nNH, n is 0 to 10, each x is independently 2 to 6, preferably 2; each of Rl and R2 is independently H, or 8 Cl to C20- alkyl or alkyl aromaticmoiety, preferably, H or CH3. Preferably, n is not more than 10 and is preferably from 0 to 6, more preferably from 0 to 4. Compositions in which x is 2 or 6 may readily be made from widely available reactants, i.e., diethylenetriamine snd dihexa-methylenetriamine and to that extent are preferred.
Another suitable class of compounds is represented by the formula:

(9) R -NH- (CH2)yNH~ ICI -O-FH-CH-OH
O Rl R2 wherein y is 2 or 3, each of Rl and R2 is as defined above, snd Rm is a Cl to C20 alkyl, cycloalkyl or alkyl sromatic moiety, or any such moiety containing, in addition to at least one carbon atom, one or more heteroatoms. In this class of compounds, starting materials which would provide alkyl, cycloalkyl or alkyl aromatic moieties greater than C20 are not readily available. The Cl to C20 alkyl, cycloalkyl or alkyl aromatic moieties of all the formulas given herein, and somewhat shorter chains, i.e., Cl to C18 slkyl or alkyl aromatic moieties, are to that extent preferred.
Another class of suitable compounds is represented by the formula:

(10) NH - ~ - O- ~CH - ~;H - OH

R6~4 -R~ H R5 1~82414 wherein esch of Rl and R2 is as defined sbove, esch o~ R4 and R6 is independently H or a Cl to C4 alkyl moiety and each of R5 and R7 is independently a Cl to-C4 alkyl moiety. Preferably, Rl and R2 are independently H or CH3 and each of R4, R5, R6 and R7 is CH3.
Another suitable class of compounds in accordance with the invention has the formuls:

(Il) ~
H- - NH-R8- NH-IC -O - CH--CH~H
~ O Rl A2 H- -NH-R8-NH-~-0 1j:H~H-OH
b Rl R2 NH--R8-NH-I~-O-(~H--f~H-OH
b Rl R2 wherein each of Rl and R2 is as defined above and each R8 is independently a C2 to C6 alkylene moiety, preferably ~CH2)2- or -~CH2)6-.
The preparation of specific preferred embodiments of the present invention is illustrated by the following examples:

E~AMPLE 1 51 g (0.5 mole) of diethylenetriamine in 150 ml. of methanol were sdded, at 15 C, to 168 g (1.65 moles) of propylene carbonste. After completion of addition, the materials were allowed to react for 24 hours at 25 C. Potentiometric titration indicated the presence of free secondsry amine. The reaction mixture was then heated to 70 C
and held st that temperature for 3 hours. Additional potentiometric titration indicated very little chsnge in the free amine content. Methanol was removed from the reaction mixture leaving behind a syrupy liquid comprised of about 72 ?6 solids containing bis(2-hydroxy-1-methylethyl)(imminodiethylene)biscarbamate.

1~8Z414 E~AMPLE 2 To a 3-necl~ flasl~ suitably equipped with 8 stirrer and a thermometer were sdded 103 g (I mole) of diethylenetriamine and 200 g of-methanoL To the resulting methanolic solution of diethylenetriamine, 184.8 g (2.1 moles) of ethylene carbonate were added in slow increments. At the completion of the ethylene carbonate addition the reaction temperature had risen from room temperature to 65 C. The reaction mixture was allowed to react for several hours without any external heat being supplied.
After removsl of methanol by distillation, the residue solidified on standing. The solid residue was recrystalized from ethanol as white solids and isolated in 90% yields. The product was characterized by I.R., N.M.R. and potentiometric titration to be bis(2-hydroxyethyl)(imminodiethylene)biscarbamate, m.p. 98 C.

408 g (4 moles) of propylene carbonate and 300 g of methanol were placed in a 3-neck flask suitably equipped with a stirrer and a thermometer. Under 8 nitrogen blanket, 292 g (2 moles) of triethylenetetramine were slowly added, maintaining the temperature between 15 to 30 C by external cooling. After addition was completed, the reaction mixture was heated to 80 C for about 8 hours. After this period almost all propylene carbonate had reacted as indicated by I.R. of the reaction mixture.
I qethanol was then removed by distillation. On standing at room temperature theproduct solidified to a low melting waxy solid. The I.R. and potentiometric titration of the product were consistent with the following bishydroxypropyl carbamate structure and the amine equivalent weight found was 210 (calculated value, 175).

Diethylenetriamine in the amount of 206 grams (2 moles) and 600 grams of methanol were added to a suitable reactor. 612 grams (6 moles) of propylene carbonate, which amount comprises 2 moles in excess of the stoichiometric amount, was slowly 1~8Z414 .
g sdded to the reactor under a nitrogen blanket while the temperature of the resctants was maintained at 15 to 20 C by ice bath cooling. After complete addition, the mixture was stirred 8 hours at room temperature. Methanol was then removed by use of water pump vacuum and with steam bath heating. The resulting product solutioncomprised diethylenetriamine bishydroxypropyl carbamate and was 73% solids in propy-lene carbonate (theory 75% solids), had 2.16 meq/g secondary amine (theory 2.37 meq/g at 73% solids), and gave characteristic bands in the infrared for the hydroxypropyl carbamate groups.

Ea~AMPLE S
Diethylenetriamine in the amount of 206 grams (2 moles) was added to a suitable reactor equipped with an inlet for a nitrogen atmosphere and with a decanting trap in the distillate return line. The reac~or was cooled in an ice bath and propylene carbonate (306 grams, 3 moles) was slowly added with good stirring, while maintaining the temperature below 40 C. Upon complete addition, the reactor was heated and stirred at 80C for 2 hours after which time no unreacted propylene carbonate could be detected by infrsred analysis. To the reactor was then added 300 grams (3 moles) of methyl isobutyl ketone (MIBK) and the contents were brought to reflux. After refluxing approximately two hours, the theoretical amount of water was collected in the decanting trap and the reactor was cooled. The resulting product comprising a mixed carbamate/ketimine of diethylenetriamine was 73~6 solids in MIBK (theory 74.8%
solids). Non-aqueous potentiometric titration for secondary amine disclosed 2.58 meq/g amine (theory for 7396 solids is 2.46 meq/g) and the infrared showed the characteristic bands for hydroxypropyl carbamate and ketimine groups.

The foregoing examples illustrate the preparation of compounds in accordance with the present invention obtained by reacting, in the illustrated embodiments, either ethylene carbonate or propylene carbonate with a multi-functional amine to obtain carbamate compounds in accordance with the present invention having at least oneunreacted secondary amine group.
Generslly, the utilization of similar reactive techniques may be employed to prepare other hydroxyalkyl carbamate compounds in accordance with the invention, as follows:

~ -lo- 1~824~4 (12) HN (cH2cH2NHcocHcH2oH) 2 (13) O O
HOCHz~CHOCNH(CH2)2NH(CH2)zNH(CHz)2NHCOICHCH20H
RC Rc (14) o R~ c HN
(CH2)6NHICIO~CH CH20H
RC

.
(15) CH2 C NH(CH2)6NHCOCHCH20H
., I
fH Cu NH(CH2~6N~ Iclocl HcH2o NH (CH2)6NHCOCHCH20H
o Rc (16) (C2H50)3SiCH2CH2NHCH2CH2NHCOCH CH20H
C

1~82~14 (17) RdNHCH2cH2cH2 R 1 2 o Rc wherein, in (12) - (17) above, Rc is independently H or a Cl to C18 alkyl moiety and, in ~17) above, Rd is independently a Cl to C18 alkyl moiety.

The following two examples illustrate the preparation of a hydroxyprowl carba-mate of the c18ss of compounds of formuls (15), sbove, by prepsrstion of a suitable multi-functional polyamine and reaction of the multi-functional amine with a cyclic carbonate.

PreDaration of N,N-bis(6-aminohex~v1)-2~(6-aminohexyl)amino] butanediamide Dimethyl maleate (72 grams, 0.5 moles) was added over a 2 to 3 hour period to a solution of 174 grams (1.5 moles) of 1,6-hexanediamine in 360 grams of toluene at 75 to 80 C. The reaction temperature rose from 80 to 110 C under reflux conditions.
After the addition was completed, methanol was distilled at 8 reaction temperature of 120 to 125 C. Additional toluene (320 grams) was added to maintain reaction volume. The course of the reaction may be followed by amine titration or by disappearance of the methyl ester in the 'H NMR spectrum. After the reaction wascomplete, toluene was removed under vacuum (50 to 70C, 15 to 20 mm Hg) to give a viscous liquid which solidified on standing. Potentiometric analysis indicated a 3/1 ratio of primary to secondary amine. NMR and IR spectra were consistent with thedesired N, N-bis(6-aminohexyl)-2[(6-aminohexyl)amino] butanediamide structure.

The following example illustrates the preparation of a tris(hydroxyalkyl carbamate) compound of the invention utilizing the diamide of Example 6.

To 100 grams (0.125 mole) of a 50% solution of the diamide of Example 6 in ethanol, were added 36 grams (0.32 mole) of propylene carbonate and 35 grams of ethanol.
The reaction mixture was allowed to react at 25 C1 overnight. The titration of the lX8Z414 .

reaction mixture indicated that essentially all the primary amino groups had reacted and the secondary amine remained free. After removal of the solvent, a syrupy product was obtained mainly consisting of a compound of the following structure:

CH2C-NI~ (CH2) 6NH- C-O-~H-CH2011 ¦H_C NI~ (CH2) 6NH-E- O-CH - CH2OH

NH (CH2) 6NH~ -ClH-CH2H

The hydroxyalkyl carbamQte-containing amine of the present invention has utilityin serving as a means whereby one or more hydroxyalkyl carbamate groups may be anchored to a variety of backbone resins in order to provide resins which are cross-linkable through the hydroxyalkyl carbamate groups. Typical polymers on which the hydroxyalkyl carbamate-containing amines of the present invention may be anchored are epoxy resins, scrylic resins, polybutadiene resins and polyester resins. In order to provide a site on the backbone polymer on which the amines of the present invention may be anchored, each molecule of such polymer should have at least one, and preferably more, reactive sites thereon which can react with the secondary amine group of the hydroxyalkyl carbamate~ontaining amine of the invention. Such reactive sites mayinclude, without limitation, one or more of the following groups:

(18) (19) -C-X (Halogenated Aliphatics, (Acid halides, in which X in which X is a halogen, is a halogen, preferably preferably Cl, Br or I) Cl,Br or I) (20) (21) O
C C / \
0// ~0/ ~O C=C O--(alnha, beta unsatu. ated (Anhydrides) e s t e rs) 1..~824~4 (22) (23) o Ic F~
~C NHCH2OH
(alpha,beta unsaturated ( N-Methylolamides) ketones) (24) (25) ~CH20H

H
(Methylolated Phenols) (Epoxies) (26) (27) - NCO
(Isocyanates) C~
~HCH20H
lethylol Carbamates) A suitable class of reactive sites on a polymer are epoxy groups, for example, suitable resins are acrylic resins with pendant glycidyl ether groups, epoxy resins derived by reaction of epichlorohydrin and bisphenol-A, or epoxy resins derived by reaction of epichlorohydrin with phenol formaldehyde resins. In addition, polybutadiene resins with pendant epoxy groups are also well suited to have the hydroxyalkyl csrbamate-containing amines of the invention anchored thereon in order to provide a cross-linkable polymer.
Generally, such polymers suitQble for utilization in the field of coatings have molecular weights in the range of 300 to 100,000, more preferably in the range of 600 to 20,000, and epoxy resins within this molecular weight range are preferred. The resulting 1'~8~414 urethane cross-linkable resins are particularly well suited for a variety of uses in the field of coatings, such as solvent or water based coatings, powder coatings, electro-coating compositions, spray roller and dip type coatings, and the like. Such coatings are normally applied to a substrate such as a metal, textile, plastic or paper. Generally, the cross-linking compounds of the invention find a wide variety of ùses including the preparation of thermosetting resins useful in preparing urethane coatings which are organic solvent, abrasion and water resistant, as well as in the preparation of adhesives and laminating resins.

The following examples illustrate the utilization of compounds in sccordance with the present invention in the preparation of urethane cross-linked polymer coatings.

E~AMPLE 8 A. A self-cross-linking novalac hydroxypropyl carbamate-containing resin which c an be reduced with water to at least 12% solids as a clear solution with 20% by total weight of cosolvent was prepared from the following ingredients:

Parts by Weight Eauivalents Solids EPN 1139* 128.3 0.75 128.3 Carbamate-containing Amine of Example 4 34~.3 0.75 253.5 *Ciba Geigy Co. reaction product of phenol-formaldehyde condensate with epichloro-hydrin The EPN 1139 and carbamate-containing amine of Example 4 were added under nitrogen to a suitable reactor equipped with a Cowels high speed stirrer, controlling the exotherm by external cooling when necessary. The final product had a solids content of 8096.
B. A sprayable aqueous composition was prepared by dissolving 100 parts of the novalac-hydroxypropyl carbamate-containing resin of part A of this Example in 100 parts of de10nized water and 15.4 parts of 1 Molar tetrabutyl ammonium hydroxidecatalyst. The resulting clear solution contained only 996 organic solvent and was 39%
solids. Aluminum panels were sprayed and then baked at 250F for 20 minutes. Theresulting cured coatings were 0.5 - 0.6 mil thick, had 4H pencil hardness, passed 40 in-lb reverse impact, were smooth and glossy, and resisted greater than 300 MEK and water double rubs.

lS 1~82414 E~AMPLE 9 A. A self-cross-linking cathodic electrocoating composition containing tertiary amine groups and ketimine groups is prepared from the following ingredients:

Parts b!l Weight Equivalents EPON 1004F* 780.0 1.00 MIBK 176.0 Carbamate-containing Amine of Example 5 302.0 0.78 Propasol P~ 105.0 EPON 1001F~ 96.8 0.20 Diethylamine 32.0 0.44 ~A trademark of Shell Chemical Co. for its product comprising the reaction product of epichlorohydrin and bisphenol-A.
~A trademark of Union Carbide Corp. for its propoxypropanol product.
B. The EPON 1004F and MIBK were charged under nitrogen in a suitable reactor and the mixture was heated to reflux with stirring to remove any water present. At 80C the carbamate-containing amine of Example S was added followed by the EPON
1001F and one-half of the Propasol P. The mixture was stirred and held at 80C for two hours and then the diethylamine dissolved in the remaining Propasol P was slowly added so as to prevent volatilization. The mixure was then stirred and heated at85C for 8 hours. l50 grams of Propasol P was then added and removed by vacuum distillation (flask temperature 110 to 120C). This process was repeated with another 150 grams of Propasol P. The resultant product comprised 76~6 by weight resin solids and 0.91 meq amine per gram; based on 100~6 resin solids.
C. An electrodeposition bath was prepared by combining 50 grams of the self-cross-linking cathodic electrocoating resin obtained in part B of this Example with 5 grams of hexyl Cellosolve, S grams of benzyl hydroxypropyl csrbamste (a reactive diluent-flow agent prepared by reacting one equivalent of benzyl amine with one equivalent ofpropylene carbonate and removing any residual amine with acidic ion-exchange resin);
10 grams of EPON 828 (Shell Chemical Co.), 1.54 grams of 89.9?6 formic acid, and 1.63 grams of dibutyltindilaurate. 376 grams of deionized water was then slowly addedwhile rapidly mixing with a Cowels stirrer to produce a bath containing spproximately 12% solids. The bath had a pH of 4.4, a conductivity of 1300 micromho cm 1, and a rupture voltage of 270 volts.
D. The bath composition obtained in part C of this Example was applied, by electrodeposition, to aluminum panels serving as the cathode at 75~ for 20 seconds to deposit a thin resin coating on the panels. The panels were then baked at 175C for l~B2414 --20 minutes and afforded film builds of 0.4 mils. The coatings were smooth, flexible,had 4H pencil hardness, passed 40 in-lb impact tests, and resisted grester than 200 methyl ethyl ketone double rubs.
The compounds of the invention not only provide an effective means of anchoring hydroxyalkyl carbamste groups on resins to obtsin self-cross-linkable systems as shown by Examples 8 and 9, but may be employed to form coatings by self-condensation of these compounds, as illustrated by the following Example.

E~AMPLE 10 A spraysble composition as prepared by dissolving 100 parts of the hydroxyalkyl carbamate-containing smine of Example 3 in 100 parts of deionized wster and adding lL6 parts of 1 Molar tetrabutyl ammonium hydroxide catalyst. The resulting solution, which was 48% solids in water, was sprayed onto aluminum panels to deposit a coating thereon. The thus-coated panels were cured at 300F for 20 minutes. The cured film thicknesses were 0.3 to 0.4 mil. The coatings were slightly hazy but smooth, had F
pencil hardness, passed 40 in-lb impact and resisted 300 MEK double rubs. However, 40 rubs with water removed the films from the panels.

As indicated in Example 10, the coatings obtained by self-condensation were resistant to organic agents but were susceptible to attack by water. Water sensitivity of the film could be improved however, by incorporation into the polymer of one or moresuitable hydrophobic hydroxyalkyl carbamate-containing amines.
Generally, among suitable amines utilizable in the invention are fatty acid diamines of the general formula RNHCH2CH2CH2NH2 wherein R is a Cl to C20 organic moiety, e.g., hydrogensted tallow diamine, tall oil diamine, coco diamine, oleyl diamine and the like; ether diamines of the general formula R'OCH2CH2CH2NHCH2CH2CH2NH2, wherein R' is a Cl - C15 organic moiety; and silyl amines of the general formula (C2H50)3SiCH2CH2CH2NHCH2CH2CH2NH2.
Preferred multi-functional amines for reacting with the cyclic carbonate include, for example, diethylene triamine and triethylene tetramine and preferred hydroxyalkyl carbamate compounds are diethylenetriamine bishydroxyethyl carbamate and triethylene-tetramine bishydroxypropyl carbamate. It will be appreciated that those skilled in the art will, when utilizing polyamine, select conditions and reactants so as to avoid gellation in forming the polymer.

-17- 1,~824~4 Generally, the organic moiety ~'R" in the hydroxyalkyl carbamate-containing amine may be any suitable organic moiety including those containing additional hydroxyalkyl carbamate groups and/or ketimine groups. For example, for some applications, thecompound of the invention is advantageously prepared with ketimine groups which may ultimately be hydrolyzed to amine groups.
Generally, reference herein and in the claims to hydroxyalkyl carbamates and compounds containing the same, including structural formulas of the same, is intended to include the various isomeric species thereof, if any.
While the invention has been described with respect to specific preferred embodiments, it will be apparent to one skilled in the art that numerous variations may be made to the embodiments without departing from the spirit and scope of the invention.

Claims (6)

1. A process for preparing a hydroxyalkyl carbamate-containing amine of the formula wherein each of R1, R2 and R3 is independently H, C1 to C20 alkyl, C3 to C8 cycloalkyl, C3 to C8 aryl, C1 to C8-alkyl-C3 - C8-aryl, or a corresponding alkyl, cycloalkyl, aryl or alkaryl group in which one or more of the respective carbon atoms has been substituted by one or more heteroatoms, wherein R-NH is selected from a group consisting of RC,-(NH-Rd)n2-NH-Re, 12a wherein n2 is O to 5 and each of Rc,, Rd and Re, is independently C2 to C6 hydrocarbyl and at least one of Rc, and Re, comprises the NH group attached to the R radical;
8a wherein A is [NH(CH2)x]nNH, n is 0 to 10, each x is independently 2 to 6 and each of R1 and R2 are as defined above;
Rm-NH-(CH2)y-NH 9a wherein y is 2 or 3 and Rm has the same definition as R1, R2 or R3 as defined above with the proviso that it does not represent hydrogen;

10a wherein each of R4 and R6 is independently H or C1 to C4 alkyl and each of R5 and R7 is independently C1 to C4 alkyl;
or 11 a wherein each R8 is independently a C2 to C6 alkylene moiety, at least one R9a represents a bond and the remaining R9a radicals represent hydrogen or wherein R1 and R2 are as defined above which process comprises reacting a 5- or 6-membered ring cyclic carbonate with a multi-functional amine selected from the group consisting of:

(a) RC-(NH-Rd)n2 -NH Re 12b wherein n2 is 0 to 5 and each of Rc, Rd and Re is independently C2 to C6 hydrocarbyl and at least one of Rc and Re contains a primary amine group;

(b) 8b wherein A, n, x and each of R1 and R2 are as defined above;
(c) Rm-NH-(CH2)y-NH2 9b wherein y and Rm are as defined above;
(d) 10b wherein R4, R5, R6 and R7 are each as defined above;
or (e) wherein each R8 is independently a C2 to C6 alkylene moiety, at least one R9 represents hydrogen and the remaining R9 radicals represent hydrogen or wherein R1 and R2 are as defined above.

2. The method of claim 1 wherein n-O.

3. The method of claim 1 comprising mixing said cyclic carbonate and said multi-functional amine to form a reaction mixture and heating the reaction mixture to form said hydroxyalkyl carbamate.

4. The method of claim 2 wherein said amine is diethylenetriamine and said cyclic carbonate is selected from the group consisting of ethylene carbonate and propylene carbonate.

5. The method of claim 1 including heating the combined reactants at a temperature of about 0 to 60 degrees C.

6. The method of claim 5 wherein said heating is carried out at a temperature of about 0 to 60 degrees C.