Curable compositions

Abstract

A curable composition comprises a) at least one epoxide compound E having at least two epoxide groups; b) at least one amine A having at least two amine hydrogens; and c) at least one acrylic ester U; wherein the epoxide compound E comprises at least one epoxide compound E, the amine A comprises at least one amine A, and the acrylic ester U comprises at least one acrylic ester U whose Hansen solubility parameters for the dipole forces .sub.p and for the specific interactions .sub.h satisfy the following conditions: $\sqrt{{\left({}_{p\left(U^{}\right)}-{}_{p\left(E^{}\right)}\right)}^2+{\left({}_{h\left(U^{}\right)}-{}_{h\left(E^{}\right)}\right)}^2}1.5\mathrm{and}$$\sqrt{\left({}_{p\left(U^{}\right)}^2+{}_{h\left(U^{}\right)}^2\right)}-\sqrt{\left({}_{p\left(A^{}\right)}^2+{}_{h\left(A^{}\right)}^2\right)}0.$
A suitable choice of the Hansen solubility parameters of the constituents ensures that the acrylic ester is incorporated covalently into the curing material, preventing subsequent evaporation of the diluent.

Claims

1. A curable composition comprising: a) at least one epoxide compound E having at least two epoxide groups; b) at least one amine A having at least two amine hydrogens; and c) at least one acrylic ester U; wherein the epoxide compound E comprises at least one epoxide compound E, the amine A comprises at least one amine A, and the acrylic ester U comprises at least one monofunctional acrylic ester U comprising at least one hydroxyl group, at least one ether group, at least one amide group, and/or at least one amine group, whose Hansen solubility parameters for the dipole forces .sub.p and for the specific interactions .sub.h, satisfy the following conditions: $\sqrt{{\left({}_{p\left(U^{}\right)}-{}_{p\left(E^{}\right)}\right)}^2+{\left({}_{h\left(U^{}\right)}-{}_{h\left(E^{}\right)}\right)}^2}1.5\mathrm{and}$ $\sqrt{\left({}_{p\left(U^{}\right)}^2+{}_{h\left(U^{}\right)}^2\right)}-\sqrt{\left({}_{p\left(A^{}\right)}^2+{}_{h\left(A^{}\right)}^2\right)}0;$ wherein .sub.p(U), .sub.p(E), and .sub.p(A) are the Hansen solubility parameters for the dipole forces for the at least one acrylic ester, the at least one epoxide compound, and the at least one amine, respectively, and .sub.h(U), .sub.h(E), and .sub.h(A) are the Hansen solubility parameters for the specific interactions for the at least one acrylic ester, the at least one epoxide compound, and the at least one amine, respectively.

2. The curable composition according to claim 1, the ratio of the amount of substance of the epoxide groups and acrylic ester groups to the amount of substance of amine hydrogens being in the range from 0.05 to 2.0.

3. The curable composition according to claim 2, the ratio of the amount of substance of the epoxide groups and acrylic ester groups to the amount of substance of amine hydrogens being in the range from 0.1 to 1.0.

4. The curable composition according to claim 1, the epoxide compound E being selected from the group consisting of glycidyl ethers, glycidyl esters, divinylarene dioxides, and polyacrylate resins containing epoxide groups.

5. The curable composition according to claim 4, the epoxide compound E being selected from the group consisting of aromatic, aliphatic, and cycloaliphatic glycidyl ethers.

6. The curable composition according to claim 5, the epoxide compound E being selected from aromatic glycidyl ethers.

7. The curable composition according to claim 6, the epoxide compound E being bisphenol A diglycidyl ether.

8. The curable composition according to claim 1, the amine A being selected from aromatic, aliphatic, or cycloaliphatic amines which have at least two amino groups which are primary and/or secondary.

9. The curable composition according to claim 8, the amine A being a cycloaliphatic diamine.

10. The curable composition according to claim 9, the amine A being isophoronediamine.

11. The curable composition according to claim 1, the monofunctional acrylic ester U being selected from the group consisting of hydroxyalkyl acrylic esters, hydroxyalkyl ester acrylic esters, and polyalkyl ether acrylic esters.

12. The curable composition according to claim 11, the monofunctional acrylic ester U being selected from the group consisting of 4-hydroxybutyl acrylate, hydroxyethylcaprolactone acrylate, and ethyl diglycol acrylate.

13. The curable composition according to claim 1, the composition comprising less than 10 wt % of inert organic solvents.

14. A method for curing a composition according to claim 1, comprising mixing the constituents of the composition.

Description

EXAMPLES

(1) Hansen solubility parameters were calculated using the modeling software HSPIP 3.1.25 (3rd Edition), developed and marketed by C. M. Hansen. Table 1 indicates the Hansen solubility parameters relevant in the examples, and the values for .sub.1 and .sub.2 that are calculated from these parameters.

(2) TABLE-US-00001 TABLE 1 .sub.d .sub.p .sub.h .sub.1 .sub.2 Bisphenol A diglycidyl ether 19.4 5.7 5.9 Isophoronediamine 16.5 5.4 8.1 Benzyl alcohol 19.3 6.4 12.6 n-Butyl acrylate 15.7 5.0 6.0 0.71 1.92 4-Hydroxybutyl acrylate 16.2 12.5 14.1 10.65 9.11 Hydroxyethylcaprolactone acrylate 16.6 10.5 10.0 6.31 4.77 Ethyl diglycol acrylate 16.0 6.3 8.7 2.86 1.01

Comparative Example 1

(3) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and benzyl alcohol (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The glass transition temperature T.sub.g of the resulting material was 94 C.

(4) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. Benzyl alcohol was detectable in the filtrate using .sup.1H NMR spectroscopy.

(5) It is evident that benzyl alcohol has been leached from the material.

Inventive Example 1

(6) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The glass transition temperature T.sub.g of the resulting material was 93 C. This value is virtually identical to the T.sub.g value obtained in comparative example 1.

(7) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. No 4-hydroxybutyl acrylate was detectable in the filtrate using .sup.1H NMR spectroscopy.

(8) From the comparison of inventive example 1 with comparative example 1 it is evident that the use of 4-hydroxybutyl acrylate rather than benzyl alcohol has no significant effect on the physical properties of the cured composition. It is also evident that the use of 4-hydroxybutyl acrylate as reactive diluent is not accompanied by any subsequent leaching of the diluent.

Comparative Example 2

(9) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and benzyl alcohol (1.5 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The glass transition temperature T.sub.g of the resulting material was 99 C.

(10) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. Benzyl alcohol was detectable in the filtrate using .sup.1H NMR spectroscopy.

Inventive Example 2

(11) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The glass transition temperature T.sub.g of the resulting material was 102 C.

(12) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. No 4-hydroxybutyl acrylate was detectable in the filtrate using .sup.1H NMR spectroscopy.

Inventive Example 3

(13) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (4.0 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The glass transition temperature T.sub.g of the resulting material was 106 C.

(14) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. No 4-hydroxybutyl acrylate was detectable in the filtrate using .sup.1H NMR spectroscopy.

Comparative Example 3

(15) Isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(16) Analysis of the material by .sup.1H NMR spectroscopy showed that the 4-hydroxybutyl acrylate was fully reacted with the excess of isophoronediamine present. The .sup.1H NMR spectrum indicated Michael addition of the amine onto the double bond of the 4-hydroxybutyl acrylate.

Comparative Example 4

(17) Bisphenol A diglycidyl ether (14.0 g) and 4-hydroxybutyl acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(18) Analysis of the material by 1H NMR spectroscopy gave no indications of a reaction between bisphenol A diglycidyl ether and 4-hydroxybutyl acrylate.

(19) From the comparison of comparative example 4 with comparative example 3 it is evident that the advantage described in inventive example 1 for the use of 4-hydroxybutyl acrylate over benzyl alcohol is probably based on a covalent reaction of the 4-hydroxybutyl acrylate with the isophoronediamine.

Comparative Example 5

(20) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and benzyl alcohol (1.5 g) were mixed and the thermal kinetics were determined by dynamic scanning calorimetry (DSC) measurement. The heating rate was 5 K/min over a temperature range from room temperature to 250 C.

(21) Result: Onset: 55.5 C. Exothermic heat: 428.2 J/g Peak maximum: 92.4 C.

Inventive Example 4

(22) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed and the thermal kinetics were determined by dynamic scanning calorimetry (DSC) measurement. The heating rate was 5 K/min over a temperature range from room temperature to 250 C.

(23) Result: Onset: 57.9 C. Exothermic heat: 402.4 J/g Peak maximum: 96.4 C.

(24) From the comparison of inventive example 4 with comparative example 5 it is evident that the use of 4-hydroxybutyl acrylate rather than benzyl alcohol has no material effect on the thermal kinetics of the mixture.

Comparative Example 6

(25) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and benzyl alcohol (1.5 g) were mixed and the viscosity of the mixture was determined as a function of time, using a plate/plate (25 mm) viscometer (MCR302, Anton Paar) with a gap width of 1 mm and a shear rate of 100 at 40 C. The viscosity initially was 280 mPas. The results are listed in table 2.

Inventive Example 5

(26) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed and the viscosity of the mixture was determined as a function of time, using a plate/plate (25 mm) viscometer (MCR302, Anton Paar) with a gap width of 1 mm and a shear rate of 100 s.sup.1, at 40 C. The viscosity initially was 290 mPas. The results are listed in table 2.

(27) TABLE-US-00002 TABLE 2 500 1000 5000 10 000 mPa .Math. s mPa .Math. s mPa .Math. s mPa .Math. s Comparative example 5 13.0 min 22.7 min 41.9 min 49.4 min Inventive example 5 11.5 min 22.3 min 46.1 min 55.8 min

(28) From the comparison of inventive example 5 with comparative example 6 it is evident that the rheological properties of the polymer as well are not substantially affected by the use of 4-hydroxybutyl acrylate rather than benzyl alcohol.

Comparative Example 7

(29) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and benzyl alcohol (1.5 g) were mixed and, using a plate/plate (25 mm) viscometer (MCR302, Anton Paar) with a gap width of 1 mm and a shear rate of 100 s.sup.1, a measurement was made of the time at 75 C. required for the maximum loss modulus G.sub.max to be achieved. This value corresponds to the minimum curing time. The results are listed in table 3.

Inventive Example 6

(30) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed and, using a plate/plate (25 mm) viscometer (MCR302, Anton Paar) with a gap width of 1 mm and a shear rate of 100 s.sup.1, a measurement was made of the time at 75 C. required for the maximum loss modulus G.sub.max to be achieved. This value corresponds to the minimum curing time. The results are listed in table 3.

Inventive Example 7

(31) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (4.0 g), and 4-hydroxybutyl acrylate (1.5 g) were mixed and, using a plate/plate (25 mm) viscometer (MCR302, Anton Paar) with a gap width of 1 mm and a shear rate of 100 s.sup.1, a measurement was made of the time at 75 C. required for the maximum loss modulus G.sub.max to be achieved. This value corresponds to the minimum curing time. The results are listed in table 3.

(32) TABLE-US-00003 TABLE 3 G.sub.max (75 C.) Comparative example 7 54.8 min Inventive example 6 68.4 min Inventive example 7 48.6 min

(33) From the comparison of inventive example 6, inventive example 7, and comparative example 7, it is evident that the use of acrylic ester rather than benzyl alcohol in equal quantity has no material influence on the curing time.

Inventive Examples 8-1 and 8-2 and Comparative Example 8

(34) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and the diluent listed respectively in table 3 (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours. The respective glass transition temperature T.sub.g of the resulting material is listed in table 4.

(35) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. The filtrate was analyzed by .sup.1H NMR spectroscopy for the presence of the respective diluent. The results are listed in table 4.

(36) TABLE-US-00004 TABLE 4 Diluent # Diluent T.sub.g leached Comparative example 1 Benzyl alcohol 94 C. yes Inventive example 1 4-Hydroxybutyl acrylate 93 C. no Inventive example 8-1 Ethyl diglycol acrylate 85 C. no Inventive example 8-2 Hydroxyethylcaprolactone 90 C. no acrylate Comparative example 8 n-Butyl acrylate 76 C. yes

(37) It is evident that the use of different acrylic esters meeting the conditions according to the invention, rather than benzyl alcohol, has no material influence on the physical properties of the cured composition. It is evident, moreover, that the use of different acrylic esters meeting the conditions according to the invention does not result in any subsequent leaching of the diluent, this being an advantage over the common, unreactive solvent benzyl alcohol.

(38) In the case of comparative example 8, leaching of the n-butyl acrylate was observed. Isophoronediamine appears to tend to react more with the bisphenol A diglycidyl ether than with n-butyl acrylate.

Comparative Example 9

(39) Isophoronediamine (3.5 g) and ethyl diglycol acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(40) Analysis of the material by .sup.1H NMR spectroscopy showed that the ethyl diglycol acrylate was fully reacted with the excess of isophoronediamine present. The .sup.1H NMR spectrum indicated Michael addition of the amine onto the double bond of the ethyl diglycol acrylate.

(41) From comparative example 9 it is apparent that the advantage described in inventive example 8-1 for the use of ethyl diglycol acrylate over benzyl alcohol is probably based on a covalent reaction of the ethyl diglycol acrylate with the isophoronediamine.

Comparative Example 10

(42) Isophoronediamine (3.5 g) and hydroxyethylcaprolactone acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(43) Analysis of the material by .sup.1H NMR spectroscopy showed that the hydroxyethylcaprolactone acrylate was fully reacted with the excess of isophoronediamine present. The .sup.1H NMR spectrum indicated Michael addition of the amine onto the double bond of the hydroxyethylcaprolactone acrylate.

(44) From comparative example 10 it is apparent that the advantage described in inventive example 8-2 for the use of hydroxyethylcaprolactone acrylate over benzyl alcohol is probably based on a covalent reaction of the hydroxyethylcaprolactone acrylate with the isophoronediamine.

Comparative Example 11

(45) Isophoronediamine (3.5 g) and n-butyl acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(46) Analysis of the material by .sup.1H NMR spectroscopy showed that the n-butyl acrylate was fully reacted with the excess of isophoronediamine present. The .sup.1H NMR spectrum indicated Michael addition of the amine onto the double bond of the n-butyl acrylate.

(47) From comparative example 11 it is evident that n-butyl acrylate is capable of reacting with an amine in a Michael addition. This result supports the supposition deposited in connection with comparative example 8 that isophoronediamine tends to react more with the bisphenol A diglycidyl ether than with n-butyl acrylate.

Comparative Example 12

(48) Bisphenol A diglycidyl ether (14.0 g) and ethyl diglycol acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(49) Analysis of the material by .sup.1H NMR spectroscopy gave no indications of a reaction between bisphenol A diglycidyl ether and ethyl diglycol acrylate.

(50) From comparative example 12 it is apparent that the advantage described in inventive example 4-1 for the use of ethyl diglycol acrylate over benzyl alcohol is probably based on a covalent reaction of the ethyl diglycol acrylate with the isophoronediamine.

Comparative Example 13

(51) Bisphenol A diglycidyl ether (14.0 g) and hydroxyethylcaprolactone acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(52) Analysis of the material by .sup.1H NMR spectroscopy gave no indications of a reaction between bisphenol A diglycidyl ether and hydroxyethylcaprolactone acrylate.

(53) From comparative example 13 it is apparent that the advantage described in inventive example 4-2 for the use of hydroxyethylcaprolactone acrylate over benzyl alcohol is probably based on a covalent reaction of the hydroxyethylcaprolactone acrylate with the isophoronediamine.

Comparative Example 14

(54) Bisphenol A diglycidyl ether (14.0 g) and n-butyl acrylate (2.0 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(55) Analysis of the material by .sup.1H NMR spectroscopy gave no indications of a reaction between bisphenol A diglycidyl ether and n-butyl acrylate.

Comparative Example 15

(56) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (3.5 g), and n-butyl acrylate (1.5 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(57) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. n-Butyl acrylate was detectable in the filtrate using .sup.1H NMR spectroscopy.

Comparative Example 16

(58) Bisphenol A diglycidyl ether (14.0 g), isophoronediamine (4.0 g), and n-butyl acrylate (1.5 g) were mixed, spread out flat in a dish (diameter: 5 cm), and heated in a vacuum drying cabinet at 80 C. for 2 hours.

(59) 0.1 g of the material was stored overnight in deuterated DMSO (about 0.05 g/ml) and subsequently isolated by filtration. n-Butyl acrylate was detectable in the filtrate using NMR spectroscopy.

(60) From comparative examples 15 and 16 relative to comparative example 8 it is evident that even in the case of relatively large amounts of amine, there is insufficient covalent incorporation of the n-butyl acrylate in the course of the curing of the composition.

(61) It is evident that the use of the curable composition of the invention rather than curable compositions which comprise diluents such as benzyl alcohol or n-butyl acrylate permits covalent incorporation of the acrylic ester in the course of the curing of the composition.