DE1927320C3 - Use of ß-dicarbonyl compounds derived from cyclopentanone as additional accelerators for polyester molding or coating compounds - Google Patents

Description

where X is oxygen or the imino group and Y is an acyl, carboxylic acid ester, carbonamide or the nitrile group means as an additional accelerator to hydroperoxides as initiators and soluble Polyester molding or coating compositions containing cobalt compounds as accelerators made of unsaturated polyesters and ethylene compounds that can be polymerized onto them.

Those with hydroperoxides as initiators and cobalt compounds as accelerators without external heat input hardening of the polyesters from solutions of unsaturated polyesters in grafted polyesters brought about at room temperature Ethylene compounds existing polyester molding and coating compositions is known by / f-dicarbonyl compounds in their tautomeric enol form cobalt chelates can form, additionally accelerated. The effectiveness of such Compounds as additional accelerator is the better, the lower the one to achieve a maximum Acceleration is amount to be added.

As / i-dicarbonyl compounds were z. B. acetoacetic acid ester, Acetylaceton (Deutsche Farbenzeitschrift 14 [1960] p. 442), acetoacetic acid amide (DT-AS

11 95 491) and 5,5-dimethyldihydroresorcinol (DT-AS

12 06 584) suggested. To achieve a sufficiently short curing times which resulted to said initiator-accelerator system hardening is usually triggered at temperatures of at least +20 ⁰ C. At lower temperatures, e.g. B. + 10 ⁰ C and below, namely can no longer achieve sufficiently short curing times even when using the / i-dicarbonyl compounds.

The above / f-dicarbonyl compounds are especially used as acceleration additives to polyester lacquer coating compounds, since the modern assembly line processing, e.g. B. with the help of paint casting machines, the faster it can be carried out is, the faster the hardening takes place. However, there is a further increase in the curing speed with the previously known ß-dicarbonyl compounds not possible. There are also numerous others that have not yet been recommended for the stated purpose // - As our own experiments have shown, dicarbonyl compounds have no advantages over the State of the art. Such / f-dicarbonyl compounds are z. B.

Benzoylacetone,

Dibenzoylmethane,

1- [Thcnoyl- (2 ')] - 3,3,3-trifluoroacetone,

2-acetylcyclohexanone,

2-benzoylcyclohexanone,

2-AcetylcycIodcxJecanon,
Ethyl 3- [4-methylphenyl] -3-ketopropionate,

Ethyl 3- [3-methoxyphenyl] -3-ketopropionate,

3-ketoglutaric acid diethyl ester,
3-ketoglutaric acid diallyl ester,
Oxaloacetic acid diethyl ester,
2,4,6-trioxoheptanedioic acid 1,7-diethyl ester,
ίο dimethyl malonate,

Acetoacetic acid tert-butyl ester,
Acetoacetic acid-l ^ -dichloropropyl ^ -ester,
2-chloropropyl-1 acetoacetate,
Cyclohexyl acetoacetate,
Isopropenyl acetoacetate,
Buten-2-yl-2-acetoacetate,
Acetoacetic acid n-dodecyllhioester,
Phenyl acetoacetate,
Acetoacetic acid m-cresyl ester,
Ethyl 4-chloroacetacetate,
Methylene-bis-acetic acid ester,
Ethyl 2-ethyl acetate,
Ethyl 2-carbanilidoacetoacetate,
Triethyl methane tricarboxylate,
Ethyl stearoyl acetate,

Cyclohexanone-2-carboxylic acid methyl ester,
Cyclohexanone-2-carboxylic acid ethyl ester,
Cyclohexane-1,4-dione-2,5-dicarboxylic acid diethy 1-ester,
2-acetylacetoacetic anilide,

Cyclohexanone-2-carboxylic acid-N-propylamide,
N-acetoacetylacetamide,
N-acetoacetylurea,
N-propionyl-N '-acetoacetylthiourea,
Dehydracetic acid,
Triacetic acid lactone,
O-acetoacetylacetone oxime,
O-acetoacetylbutanone oxime and
O-acetoacetylcyclohexanone oxime.
40

DT-AS 1191100 stipulates the use of aromatic ketones with at least one enolizable Keto group as curing catalysts for hot curing (see examples and column 2, lines 19-20) known from unsaturated polyester resin compositions. However, these aromatic ketones are not as reactive as the compounds which can be used according to the invention, as can already be seen from the fact that those with the in the DT-AS 1191 100 named ketones added polyester resin masses usually only cured in the heat, while the invention is to The compounds used are suitable as additional accelerators for cold curing.

Surprisingly, it has now been found that certain compounds derived from cyclopentanone which are present in a keto / enol or ketimine / enamine equilibrium have a significantly stronger additional accelerator effect than all of the abovementioned / i-dicarbonyl compounds.
The additional accelerators derived from cyclopentanone correspond to the formulas

-Y

X-H

where X is an oxygen atom or the imino group

and Y is an acyl, carboxylic acid ester, carbonamide or nitrile group.

These connections thus occupy a special position. With their help, the hydroperoxides can be used and cobalt compounds already cause hardening of polyester mold and coating compounds Carry out temperatures below + 20 ° C with astonishing speed. The faster one Curing offers the advantage, particularly when used as coating compounds for lacquer engineering, that Wipe-proof surfaces and the objects coated therewith are already formed after a relatively short period of time can be handled and stacked after a shorter period of time.

The invention therefore relates to the use of the said, derived from cyclopentanone, im Keto / enol or ketimine / enamine equilibrium compounds as additional accelerators Polyester form containing hydroperoxides as initiators and soluble cobalt compounds as accelerators and coating compositions made from unsaturated polyesters and polymerizable ethylene compounds.

These additional accelerators are already available in amounts of about 0.05 to about 1.5 percent by weight on the polyester masses, fully effective. The most effective compounds are those where in the the above formulas for Y is an acyl, carbonamide or nitrile group; they develop theirs maximum effect even with additives up to about 0.5 percent. Slightly larger additions are required when Y is a carboxylic acid ester group.

A particular advantage when using the additional accelerators according to the invention in polyester compositions also consists in the fact that moldings and coatings can be produced, in general show no discoloration, such as yellowing or greening. This is especially true for such Compounds in which Y in the above formulas is an acyl, carboxylic acid ester or carbonamide group and X represents an oxygen atom. Such undesirable side effects are observed in the Addition of other additional accelerators, e.g. B. acetoacetic ester and acetylacetone. If using the Should a green discoloration nevertheless occur, this additional accelerator according to the invention can be passed through It is easy to add known anti-greening agents to the polyester compositions without damaging the reactivity remedy.

In general, the additional accelerators used according to the invention are well tolerated by the polyester compounds, so that no additional solvents are required. As a result of the good Tolerance and the low concentrations required to achieve maximum effect when using the additional accelerator according to the invention, the undesirable side effects, which are known to cause non-polymerizable additives to the polyester masses, largely switched off. Such side effects can be e.g. B. in the production of polyester coatings express in a swelling or dissolving of the paint surface; one observes them z. B. when using acetoacetic ester, its maximum effectiveness only with added amounts of 3 to 5 percent by weight is achieved, or also with other, inherently effective, but difficult to dissolve additional accelerators, like 5,5-dimethyldihydroresorcinol, which only works with the use of solubilizing substances can be incorporated homogeneously into the polyester masses.

The additional accelerators which can be used according to the invention can also be mixed with one another as well as in combination with additional accelerators of other types. In addition, the Masses of other common additives, such as inhibitors, fillers, thickeners, paraffin and anti-greening agents, contain.

Examples of the additional accelerators which can be used according to the invention are:

2-acetylcyclopentanone,

2-propionylcyclopentanone,

2- [3-chloropropionyl] cyclopentanone,

2-methacryloylcyclopentanone,

2-isovalerianoylcyclopentanone,

2-formylcyclopentanone,
2,5-diacetylcyclopentanone,

2-benzoylcyclopentanone,

2-acetylindanone-1,

3-acetylcamphor,

Methyl cyclopentanone-2-carboxylate,
_{2S ethyl} cyclopentanone-2-carboxylate,

Allyl cyclopentanone-2-carboxylate,

Cyclopentanone-2-carboxylic acid-N-propylamide,

Cyclopentanone-2-carboxylic acid-N-cyclohexyl-

amide,

Cyclopentanone-2-carboxylic acid-N- [methoxy-

methyl] amide,

Cyclopentanone-2-carboxylic acid anilide,

Di- [cyclopentanone-2-carboxylic acid] -hexa-

methylene-1,6-diamide,

Cyclopentanone-2-thiocarboxylic acid anilide,

2-cyanocyclopentanone and

2-cyanocyclopentanoneimine.

The additional accelerators according to the invention can be prepared by methods known from the literature take place, e.g. B. by reacting cyclopentenyl enamines with suitable acyl halides, chloroformic acid esters, Isocyanates or isothiocyanates (Chem. Reports, Vol. 95 [1962], p. 926; others there Literature).

The imino group mentioned in the formulas for X can be converted in a known manner by reacting the corresponding Keto compounds can be obtained with ammonia.

Unsaturated polyesters include, as is the case with polyester form and coating compositions, polyester containing α, / f-unsaturated dicarboxylic acid residues to understand, usually by polycondensation of «, / ^ - unsaturated dicarboxylic acids, such as Maleic acid, fumaric acid, citraconic acid and itaconic acid, or their anhydrides with polyalcohols, such as Ethylene glycol, diethylene glycol, propanediol, butanediol, butenediol, neopentyl glycol, hexanediol, trimethylolpropane and pentaerythritol. Some of the », / ^ - unsaturated dicarboxylic acids can by other polybasic carboxylic acids, e.g. B. succinic acid, adipic acid, sebacic acid, dimerized Fatty acids, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, tetrachlorophthalic acid, Hexachlorendomethylenetetrahydrophthalic acid and trimellitic acid. Modifications too by incorporating monohydric alcohols such as butanol and tetrahydrofurfuryl alcohol, as well as monobasic carboxylic acids, such as benzoic acid, tert-butylbenzoic acid, oil

acid, linoleum fatty acid and abietic acid are possible. Also mentioned are unsaturated polyesters which, in addition to the radicals, - unsaturated dicarboxylic acids according to the DT-AS 1024654 still contain / ^ - unsaturated ether residues.

Examples of monomeric ethylene compounds which can be polymerized onto the unsaturated polyester are Vinyl, acrylic, methacrylic and allyl compounds such as styrene, vinyl toluene, divinylbenzoL vinyl acetate, Vinyl propionate, esters and amides of acrylic and methacrylic acid, acrylonitrile, diallyl phthalate, diallyl maleinal and triallyl cyanurate.

To increase the storage stability, the polyester molding and coating compositions can be conventional inhibitors, such as hydroquinone, toluhydroquinone, tert-butylpyrocatechol, p-benzoquinone, also Cu compounds, z. B. Cu naphthenate included.

The peroxidic initiators are the hydroperoxides commonly used, e.g. B. cumene hydroperoxide, but preferably ketone hydroperoxides, such as cyclohexanone hydroperoxide, methyl ethyl ketone hydroperoxide, Methyl isobutyl ketone hydroperoxide and acetylacetone hydroperoxide.

Suitable cobalt accelerators are cobalt compounds which are soluble in the polyester compositions, e.g. B. the Salts of higher carboxylic acids such as cobalt octoate, cobalt naphthenate, cobalt resinate and cobalt linoleate, furthermore the cobalt salts of dicarboxylic acid half-esters and compounds with chelated cobalt of the cobalt acetoacetic ester type and Cobalt acetylacetonate. Also cobalt chelates de? additional accelerator according to the invention, for. B. of 2-acetylcyclopentanone and methyl cyclopentanone-2-carboxylate can be used.

The parts and percentages given in the following examples are parts and percentages by weight.

The polyester resins used to carry out the examples have the following composition:

Polyester resin (A)
55 parts of unsaturated polyester made from

608 parts of maleic anhydride,
562 parts of phthalic anhydride,
790 parts of 1,2-propanediol,
Acid number (DIN 53 402) 46,
Viscosity, 65% in styrene at 2O ⁰ C
(DIN 53015), I486mPas (= cP),

45 parts of styrene, 0.012 part of toluohydroquinone.

Polyester resin (B)
55 parts of unsaturated polyester made from

295 parts of maleic anhydride,
1035 parts of phthalic anhydride,

760 parts of 1,2-propanediol,
Acid number (DIN 53 402) 45,
Viscosity, 65% in styrene at 20 ° C
(DIN 53 015), 176OmPa s,

45 parts of styrene, 0.012 part of toluohydroquinone.

Polyester resin (C)
55 parts of unsaturated polyester made from

684 parts of maleic anhydride.
445 parts of phthalic anhydride,
910 parts of butanediol-1.3.

Acid number (DIN 53 402) 36,
Viscosity, 65% in styrene at 20 ° C
(DIN 53015). 1795 mPa s,

45TdIe styrene, 0.012 part toluohydroquinone.

Example I.

10 parts of polyester resin (A) are placed in test tubes with a diameter of 18 mm, as shown in Table 1 named additional accelerator and 0.4 parts of a

ίο 50% solution of cyclohexanone hydroperoxide admixed in dimethyl phthalate and the mixtures placed in a thermostat in a first test series for 20 + ^'J C and in a second row to + 10' ¹ C. 0.03 part of cobalt in the form of a 20% strength solution of cobalt naphthenate in toluene is then added to all samples and the gel times are determined at the specified temperatures. In Table I, the gel times at + 20 ^ C and + 10 ^ C and the difference between these values are given. In part (a) the experiments with the additional accelerators according to the invention are compiled; Part (b) contains comparative tests with other / i-dicarbonyl compounds as additional accelerators.

Table 1

0.3 (iclicrzcit -i 10 C Difkr-n / Imine) (min) 0.5 + 20 C (a) addition 0.3 accelerator 4.0 according to the invention 0.5 2-acetylcyclo- 0.5 2.0 4.0 2.0 pentanone 4.0 the same 2.0 2.0 2-propionyl 1.2 2.0 3.5 2.0 cyclopentanone 0.5 7.5 the same 2.0 1.5 Cyclopentanone 4.0 3.5 2-carbon5: acid 0.4 6.0 methyl ester 5.5 the same 3.0 3.0 Cyclopentanone 3.0 2.5 2-carboxylic acid 3.0 N-propylamide 2-cyanocyclo- 1.25 1.75 pentanonimine 0.25 (b) Other addition 0.5 accelerator 0.3 26.0 (Comparison tests) no addition 0.5 8.5 10.0 17.5 (Default) 0.5 11.0 Acetylacetone 4.0 18.5 6.0 the same 0.4 3.5 7.5 2-acetylcyclo- 6.5 15.0 12.0 hexanone 16.5 the same 6.0 9.0 2-acetylcyclo- 6.5 15.0 10.0 dodecanon 5,5-dimethyldi 4.5 * l In the form of a 10% solution in n-butanol. 10.5 hydroresorcin *)

I-'orlsel / ung

0.4 (! L ¹ IlL ¹ IVL ¹ Il H 10 C Dilfcrcny (min) (min) 2.5 H 20 C (b) Other addition 5.0 accelerator 0.5 20.0 (Comparison tests) Acetoacetic acid 8.0 15.0 12.0 ethyl ester 0.3 13.0 the same 0.3 6.0 16.0 9.0 the same 5.0 8.0 Cyclohexanone 0.4 6.5 9.5 2-carboxylic acid 0.3 18.0 ethyl ester 12.5 the same 0.5 7.0 11.0 Acetic acid 4.5 11.5 8.0 p-toluidid 12.0 the same 4.0 7.5 Acetoacetic acid 4.5 10.0 7.5 piperidide the same 4.0 6.0 Table 2

In the following examples 2 to 5 the polyester compositions 0.1 part of paraffin in the form of an IO% solution in toluene was added each time. The processing the Polycslerüberzugsmasscn in these examples is between 20 and 24 "C.

Example 2

ίο .Ic 100 parts of polyester resin (A) are used in the Additional accelerators mentioned in Table 2 and the hydroperoxides mentioned in the last column of the table admixed Then 0.03 parts of cobalt are added to all samples in the form of a 20% solution

is mixed with cobalt naphthenate in toluene and Immediately apply these mixtures to a pre-primed wood base in a wet film thickness of approx 500 (applied with the help of a film applicator. The drying time is measured as the time after the cobalt has been mixed in until it has formed of a wipe-proof paraffin mirror passes. Table 2 contains the drying times in part (a) the films produced with the aid of the additional accelerators according to the invention; in part (b) are the Comparative experiments with other / i-dicarbonyl compounds compiled as an additional accelerator.

Peroxide addition

Drying time

(min |

(a) Additional accelerator according to the invention 0.2 Cyclohexanone hydroperoxide ¹ ) 4.0 20th 2-acetylcyclopentanone 0.3 the same 4.0 17th the same 0.5 the same 4.0 18th the same 0.5 Methyl ethyl ketone hydroperoxide ² ) 2.7 18th the same 0.5 Acetylacetone hydroperoxide ³ ) 6.5 19th desgi. 0.25 Cyclohexanone hydroperoxide ¹ ) 4.0 17th 2-propionylcyclopentanone 0.42 the same 4.0 17th the same 0.5 the same 4.0 19th 2-acetylindanone 0.4 the same 4.0 21 Cyclopentanone-2-carboxylic acid-N-propyl- amide 1.0 the same 4.0 18th the same 0.4 the same 4.0 13th 2-cyanocyclopentanoneimine (b) Other additional accelerators (Comparison tests) - Cyclohexanone hydroperoxide ¹ ) 4.0 45 no addition (standard) - Methyl ethyl ketone hydroperoxide ² ) 3.0 35 the same - Acetylacetone hydroperoxide ³ ) 6.5 48 the same 0.5 Cyclohexanone hydroperoxide ¹ ) 4.0 45 Acetoacetic ester 3.0 the same 4.0 40 the same 5.0 the same 4.0 40 the same 0.25 the same 4.0 43 Acetylacetone 0.42 the same 4.0 38 the same 0.3 the same 4.0 45 Benzoylacetone 0.42 the same 4.0 29 5,5-dimethyldihydroresorcinol *)

*) In the form of a J0% solution in n-butanol. ') 50% in dimethyl phthalate ² ) 40% in dimethyl phthalate ³ I 40% in dimethyl phthalate.

Foiiscl / Linu

ίο

IVioxul / usal /

Tmkkcn / cil

(b) Other additional accelerators
(Comparison tests)

2-acetylcyclohexanone 0.5 C'yclohexanonhydropcroxid ') 4.0 40 2-benzoylcyclohexanone 0.8 the same 4.0 50 2-acetylcyclododecanone 0.7 the same 4.0 45 Acetoacetic acid piperidide 0.25 the same 4.0 35 the same 0.42 the same 4.0 30th the same 1.0 the same 4.0 28 the same 0.5 Methyl ethyl ketone hydroperoxide ² ) 3.0 29 the same 0.5 Acetylacetone hydroperoxide ³ ) 6.5 29 Acetoacetic acid-p-toluidjd 0.42 Cyclohexanone hydroperoxide ¹ ) 4.0 32 Cyclohexanone-2-carboxylic acid ethyl ester 0.5 the same 4.0 40 Cyclohexanone-2-carboxylic acid-N-propyl- 0.5 the same 4.0 45 amide ¹ I 5 (1 "/" ig in dimethyl phthalate. ² I 4 ()% in dimethyl phthalate. ¹ I 4 () "/ oig in dimethyl phthalate.

Example 3

The additive accelerators specified in Table 3 are used per 100 parts of polyester resin (B) and 4 parts of a 50% solution of cyclohexanone hydroperoxide in dimethyl phthalate. 0.03 parts of cobalt in the form of a 20% solution of cobalt naphthenate are then added to all samples mixed in toluene and the mixtures immediately on a pre-primed wooden base applied in a wet film thickness of about 500 μm with the aid of a film drawing device.

Table 3 contains in part (a) the drying times of the using the inventive Additional accelerator-made films; in part (b) there are comparative experiments with other / f-dicarbonyl compounds put together as an additional accelerator.

50

Table 3

0.25 Dry 0.4 time 0.25 (min) (a) Additional accelerator 0.4 according to the invention 0.4 2-acetylcyclopentanone 24 the same 20th 2-propionylcyclopentanone 23 2-acetylindanone 22nd 2-cyanocyclopentanoneimine 20th

- Dry 0.3 time 0.5 (min) (b) Other additional accelerators 0.25 (Comparison tests) 0.42 no addition 0.5 70 5,5-dimethyldihydroresorcinol *) 5.0 48 the same 0.25 40 2-acetylcyclohexanone 0.5 49 the same 0.4 38 Acetoacetic ester *) In the form of a 10% solution in n-butanol. 60 the same Example 4 45 Acetoacetic acid piperidide 40 the same 30th Acetoacetic acid benzylamide 45

For every 100 parts of polyester composition (C), the additional accelerators mentioned in Table 4 are 4 parts admixed with a 50% solution of cyclohexanone preproxide in dimethyl phthalate. Then be 0.03 part of cobalt in the form of a 20% solution of cobalt naphthenate in toluene mixed in with all samples and the mixtures immediately on a pre-primed wooden base in a wet film thickness of about 500 μπι applied with the help of a film drawing device.

Table 4 contains in part (a) the tracking times using the inventive Additional accelerator-made films; Part (b) contains the comparative experiments with other / ϊ-Diearbony lverbindungen as an additional accelerator.

Il

Table 4

(a) Additional accelerator
according to the invention

2-acetyl cyclopentanone 0.25

the same 0.4

2-propionylcyclopentanone 0.3

also 0.5

2-acetylindanone 0.4

2-cyanocyclopentanoneimine 0.4
Cyclopentanone-2-carboxylic acid c-1.0
methyl ester

(b) Other additional accelerators
(Comparison tests)

no addition

2-acetylcyclohexanone 0.3

also 0.5

Acetylacetone 0.3

also 0.5

Acetoacetic ester 0.5

also 4.0

Acetoacetic acid benzylamide 0.5

Acetoacetic acid piperidide 0.25

also 0.5

Dry / cil

(min)

20 15 ■ n

14 20 15 24

65 38 33 50 55 55 35 30 40 28 and 20 parts of cyclohexanone hydroperoxide-I'iilvcr (95%) produced.

The drying time is measured as the time from the application of the film to the Kalalysatorgrund to the formation of a smudge-proof paraffin mirror elapses.

Table 5 contains the drying times in part (a) the films produced using the additional accelerators according to the invention; Part (b) contains Comparative tests with other / i-dicarbonyl compounds as additional accelerators.

table

% Dry

time

(min)

40

Example 5

The additional accelerators mentioned in Table 5 and 0.03 part of cobalt in the form of a 20% solution of cobalt naphthenate in toluene are added to each 100 parts of polyester composition (A), and the mixtures are each applied to a wood veneer coated ^{with 100 g / m 2 of a catalyst base} a wet film thickness of about 500 μίτι applied.

The catalyst base was applied by applying a solution of 30 parts of nitrocellulose (moist butanol) in 120 parts of ethyl acetate and 35 parts of butyl acetate

(a) Additional accelerator 0.3 19th according to the invention 0.5 18th 2-acetyl cyclopentanone 0.3 20th the same 0.5 15th 2-propionylcyclopentanone 0.5 20th the same Cyclopentanone-2-carboxylic acid 0.4 13th N-propylamide 2-cyanocyclopentanoneimine (b) Other additional accelerators 50 (Comparison tests) 0.25 38 no addition 0.42 32 Acetylacetone 0.3 40 the same 0.5 35 2-acetylcyclohexanone 0.5 42 the same 5.0 33 Acetoacetic ester 0.3 35 the same 0.42 29 Acetoacetic acid piperidide 0.3 37 the same 0.42 30th Acetoacetic acid p-toluidide 0.5 45 the same Cyclohexanone-2-carboxylic acid N-propylamide

Claims (1)

Claim: Use derived from cyclopentanone in the keto / enol or ketimine / enamine equilibrium standing connections of the formulas ο: - ο X-H