Uses of condensation resins

Abstract

The present invention relates to new uses of condensation resins made from urea, formaldehyde, and CH-acidic aldehydes.

Claims

1. A method for incorporating at least one additive(s) into a composition comprising at least one epoxide compound(s), comprising: mixing the at least one additive with at least one condensation resin, wherein the at least one condensation resin comprises condensed units of formaldehyde, at least one urea, and at least one CH-acidic aldehyde, then mixing the resulting mixture of the at least one condensation resin and the at least one additive(s) with the composition comprising at least one epoxide compound(s) and at least one of a curing agent and a catalyst to form a curable epoxide mixture, wherein the curable epoxy mixture comprises from 1 to 20 wt % of the at least one additive, from 0.2 to 10 wt % of the at least one condensation resin, and 70 to 98.8 wt % of the at least one epoxide compound(s) where wt % is based on 100 wt % of the combined amounts of the at least one additive, the at least one condensation resin, and the at least one epoxide compound(s), and wherein the at least one additive is selected from the group consisting of a pigment, a flame retardant, a flow assistant, a thixotropic assistant, a diluent, and a filler.

2. The method according to claim 1, wherein the at least one epoxide compound(s) have 2 to 10 epoxide groups.

3. The method according to claim 1, wherein the at least one epoxide compound(s) have a number-average molar weight (Mn) of less than 1000 g/mol.

4. The method according to claim 1, wherein the at least one epoxide compound(s) are compounds having two aromatic or aliphatic six-membered rings or oligomers thereof.

5. The method according to claim 1, wherein the at least one condensation resin has a number-average molar weight M.sub.n of 300 to less than 3000 g/mol and a weight-average molar weight M.sub.w of 500 to 2000.

6. The method according to claim 1, wherein the at least one condensation resin has a number-average molar weight M.sub.n of 300 to less than 1000 g/mol and a weight-average molar weight M.sub.w of 500 to 2000.

7. The method according to claim 1, wherein the at least one condensation resin has a hydroxyl number to DIN ISO 4629 of 5 to 150 mg KOH/g.

8. The method according to claim 1, wherein the at least one condensation resin has a hydroxyl number to DIN ISO4629 of 50 to 120 mg KOH/g.

9. The method according to claim 1, wherein the at least one condensation resin has a glass transition temperature T.sub.g by the DSC method (Differential Scanning calorimetry) to ASTM 3418/82 with a heating rate of 2.5° C./min of less than 70° C.

10. The method according to claim 1, wherein the at least one condensation resin comprises condensed units of urea, formaldehyde, and isobutyraldehyde.

11. The method according to claim 1, wherein the mixing of the at least one additive with the at least one condensation resin takes place in a stirring vessel, mixer, extruder, disperser, or kneader.

12. The method of claim 1, wherein the at least one condensation resin comprises condensed units of formaldehyde, precisely one urea, and precisely one CH-acidic aldehyde.

13. The method of claim 1, further comprising: curing the curable epoxide mixture to form a cured composition.

14. The method of claim 1, wherein the curable epoxy mixture comprises from 2 to 15 wt % of the at least one additive, from 0.2 to 5 wt % of the at least one condensation resin, and 75 to 97.8 wt % of the at least one epoxide compound(s), where wt % is based on 100 wt % of the combined amounts of the at least one additive, the at least one condensation resin, and the at least one epoxide compound(s).

15. A curable epoxy composition comprising at least one of a curing agent and a catalyst, 1 to 20 wt % of at least one additive, 0.2 to 10 wt % of at least one condensation resin, wherein the at least one condensation resin comprises condensed units of formaldehyde, at least one urea, and at least one CH-acidic aldehyde, and 70 to 98.8 wt % of at least one epoxide compound, where wt % is based on 100 wt % of the combined amounts of the at least one additive, the at least one condensation resin, and the at least one epoxide compound(s), and wherein the at least one additive is selected from the group consisting of a pigment, a flame retardant, a flow assistant, a thixotropic assistant, a diluent, and a filler.

16. The composition of claim 15 wherein the at least one condensation resin has a number-average molar weight M.sub.n of 300 to less than 3000 g/mol and a weight-average molar weight M.sub.w of 500 to 2000 g/mol.

17. The curable epoxy composition of claim 15, comprising: 2 to 15 wt % of the at least one additive, 0.2 to 5 wt % of the at least one condensation resin, and 75 to 97.8 wt % of the at least one epoxide compound, where wt % is based on 100 wt % of the combined amounts of the at least one additive, the at least one condensation resin, and the at least one epoxide compound(s).

Description

EXAMPLES

Example 1

(1) Epoxide compound: Baxxores® ER 2200 (commercially available bisphenol A-epichlorohydrin resin from BASF SE, Ludwigshafen)

(2) Curing agent: Baxxodur® EC 2120 (commercially available epoxide hardener from BASF SE, Ludwigshafen, comprising predominantly 1,3-cyclohexylenebis(methylamine) as diamine)

(3) Adjuvant: 2% pigment paste based on Laropal® A81 with 20% pigment content (Heliogen® Blue L7101 as blue pigment)

(4) 0.2% pigment paste based on Laropal A81 with 20% pigment content (Heliogen® Blue L7101 as blue pigment)

(5) The pigment paste was composed of 32 parts of Laropal A81 (60% methoxypropyl acetate), 32.5 parts of methoxypropyl acetate, 10.5 parts of EFKA® 4330 (dispersing assistant), and the stated amount of the pigment indicated.

(6) Mixing ratio: 100/20.6 Baxxores® ER 2200/Baxxodur® EC 2120+2% or 0.2% pigment paste, based on the batch.

(7) Laropal A81® from BASF SE Ludwigshafen is a condensation product of an aliphatic aldehyde with urea and formaldehyde, having an acid number of not more than 3 mg KOH/g, a hydroxyl number of about 40 mg KOH/g, and a glass transition temperature as determined by DSC of 57° C.

(8) Procedure:

(9) The viscosity was measured at 120° C. in a cone-plate viscosimeter (from Anton Paar GmbH).

(10) The viscosity here is measured in rotation of up to 2000 mPas, and in oscillation thereafter.

(11) TABLE-US-00001 Baxxores ER 2200/Baxxodur EC 2120 (100/20.6) + 2% Laropal (blue) Initial viscosity [mPa .Math. s] 13.2 Open time [min] 0.367 Gel point [min] 0.9 Curing [min] 3 Baxxores ER 2200/Baxxodur EC 2120 (100/20.6) + 0.2% Laropal (blue) Initial viscosity [mPa .Math. s] 17.5 Open time [min] 0.35 Gel point [min] 0.87 Curing [min] 2.53 Baxxores ER 2200/Baxxodur EC 2120 (100/20.6) without adjuvant Initial viscosity [mPa .Math. s] 17.6 Open time [min] 0.27 Gel point [min] 0.75 Curing [min] 2.45

(12) It is apparent that the cure rate is affected hardly at all by the addition of the color paste. Many additives influence the curing kinetics to a substantially greater extent.

(13) Furthermore, samples of each of the above mixtures were subjected to DSC analysis in order to ascertain the extent to which the glass transition temperature is affected by the mixtures.

(14) TABLE-US-00002 Onset Peak max ΔH 1.sup.st Tg 2.sup.nd Tg Sample ° C. ° C. J/g ° C. ° C. 2% Laropal blue 51.4 82.1 554 142.2 142.7 0.2% Laropal blue 50 81.6 542.9 148.5 149.1 No Laropal blue 51.6 82.5 500 147.6 147.5 Temperature program 0-180° C.  5 K/min   180° C. 30 min isothermal 180-0° C. 20 K/min 0° C.-200° C. 20 K/min

(15) It is apparent that the glass transition temperature of the mixtures is affected hardly at all by the addition of the color paste. Many additives influence the glass transition temperature to a substantially greater extent.

Examples 2 and 3

(16) Resin: Baxxores® ER 2200

(17) Curing agent: dicyandiamide (DSH-100 from AlzChem AG, cyanoguanidine)

(18) Catalyst: imidazole derivate

(19) Adjuvant: pigment paste based on Laropal A81 with 25% pigment content (carbon black)

(20) The pigment paste was composed of 32 parts of Laropal A81 (60% methoxypropyl acetate), 32.5 parts of methoxypropyl acetate, 10.5 parts of EFKA® 4330 (dispersing assistant), and the stated amount of the pigment indicated.

(21) The individual components were mixed with one another, as stated in the table below, and Tg, gel time at 140° C., and curing time at 140° C. were ascertained.

(22) TABLE-US-00003 Epoxy Imid- resin azole Baxxores DSH- der- Laropal Tg Gel Curing ER2200 100 ivate black ° C. time time Compar- 100 6 1 0 163 2.8 min 6.8 min ative Example 2 100 6 1 0.5 160 1.9 min 5.4 min Example 3 100 6 1 1 160 2.0 min 6.1 min

(23) It is apparent that the addition of the condensation resin produces only a small effect on the glass transition temperature of the resin. At the same time the systems display a shortened gel time and curing time.

Examples 4 to 7

(24) Resin: Baxxores® ER 2200

(25) Curing agent: dicyandiamide (DSH-100)

(26) Catalyst: imidazole derivate

(27) The following mixtures were prepared:

(28) TABLE-US-00004 Baxxores DSH- Laropal EP S PE Tg Gel time Curing time ER2200 100 Cat black CM15 TNF PE39 ° C. @140° C. @ 140° C. For comp. 100 6 1 163 2.8 min 6.8 min 4 100 6 1 0.5 160 1.9 min 5.4 min 5 100 6 1 0.5 156 3.3 min 7.1 min 6 100 6 1 0.5 155 3 min 7 min 7 100 6 1 0.5 159 3.4 min 9 min

(29) It is apparent that the addition of the condensation resin (inventive example 4) produces only a small effect on the glass transition temperature and reactivity of the resin.

(30) In contrast, when using the commercial products Temacolor™ EP CM15 (epoxy-based carbon black paste from CPS Color) and Temacolor™ S TNF (solvent-based, from CPS Color), a glass transition temperature reduced by about 7-8° C. is observed (noninventive examples 5 and 6).

(31) The commercial carbon black paste Auricolor™ PE PE39 from CPS Color, although displaying a small influence on the glass transition temperature, nevertheless exhibited a prolonged curing time (noninventive example 7).

Examples 8 to 11

(32) Resin: Baxxores® ER 2200

(33) Curing agent: dicyandiamide (DSH-100)

(34) Catalyst: imidazole derivate

(35) The following mixtures were prepared and used to produce plates by casting of the mixtures between two metal sheets of size 220*340 mm in a thickness of 4 mm. Curing took place over 0.5 hour at 80° C., followed by 1 hour at 140° C.

(36) The flexural strength and breaking strength of the plates was ascertained, and additionally the modulus of elasticity, force, and maximum rotation before fracture by tensile strength DIN EN ISO 527-2 (specimen 1A) and flexural test DIN EN ISO 178 (specimen 80×10×4 mm) were ascertained.

(37) TABLE-US-00005 Flexural strength E- Breaking strength Baxxores Laropal modulus_f σ_fM ε_fM E-modulus σ_M ε_M Ex. ER2200 Cat. black Mpa Mpa % Mpa Mpa % 8 100 5 0 2978 105.30 5.82 2905 58.24 2.96 9 100 5 0.5 3053 100.96 5.05 2914 63.26 3.34

(38) TABLE-US-00006 Flexural strength E- Baxxores DSH- Laropal modulus_f σ_fM ε_fM Ex. ER2200 100 Cat. Black Mpa Mpa % 10 100 9 1 0 3314 129.66 6.14 11 100 9 1 0.5 3463 133.02 5.83

(39) It is apparent that adding the condensation resin (inventive examples 9 and 11 in comparison to the noninventive examples 8 and 10) has no adverse effect on breaking strength (tensile strength) and flexural strength.