Process for producing porous materials

Abstract

A process for preparing a porous material involves at least the steps of providing a mixture (I) containing a composition (A), which contains components suitable to from an organic gel, and a solvent (B); reacting the components in the composition (A) in the presence of the solvent (B) to form a gel; and drying of the gel. The composition (A) contains a catalyst system (CS), which contains at least a catalyst component (C1) selected from ammonium salts and phosphonium salts, and an acid with a phosphor containing acid group as a catalyst component (C2). Porous materials can be obtained in this way and the porous materials can be used as thermal insulation material and in vacuum insulation panels and vacuum insulation systems, in particular in interior or exterior thermal insulation systems as well as for insulation of refrigerators and freezers and in water tank or ice maker insulation systems.

Claims

1-15. (canceled)

16: A process for preparing a porous material, at least comprising: a) providing a mixture (I) comprising: (i) a composition (A) comprising components suitable to form an organic gel, and (ii) a solvent (B); b) reacting the components in the composition (A) in the presence of the solvent (B) to form a gel; and c) drying of the gel obtained in b); wherein the composition (A) comprises a catalyst system (CS) at least comprising: (i) a catalyst component (C1) selected from the group consisting of an ammonium salt and a phosphonium salt, and (ii) an acid comprising a phosphor containing acid group as a catalyst component (C2); wherein the composition (A) comprises at least one polyfunctional isocyanate as component (a1), comprises at least one aromatic amine as component (a2), comprises water as component (a3), and comprises at least one further catalyst as component (a4), and wherein the component (a4) is at least one selected from the group consisting of primary, secondary, and tertiary amines; triazine derivatives; metal-organic compounds; metal chelates; oxides of phospholenes; quaternary ammonium salts; ammonium hydroxides; and alkali metal and alkaline earth metal hydroxides, alkoxides, and carboxylates.

17: The process according to claim 16, wherein the catalyst component (C1) is selected from the group consisting of tetraalkylammonium salts and tetraalkylphosphonium salts.

18: The process according to claim 16, wherein the catalyst component (C1) is selected from the group consisting of tetraalkylammonium hydroxides and tetraalkylphosphonium hydroxides.

19: The process according to claim 16, wherein the catalyst component (C1) is selected from the group consisting of tetramethylammonium hydroxide, tetra(n-butyl)ammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, hexadecyltrimethylammonium hydroxide, tetrahexylammonium hydroxide, triethylmethylammonium hydroxide, tetraoctylammonium hydroxide, tri-n-butylmethylammonium hydroxide, diethyldimethylammonium hydroxide, octyltrimethylammonium hydroxide, trimethylethylammonium hydroxide, tetrapentylammonium hydroxide, tripropylmethylammonium hydroxide, tetrakisdecylammonium hydroxide, tributyl ethyl ammonium hydroxide, tetramethylphosphonium hydroxide, tetra(n-butyl)phosphonium hydroxide, tetrapropylphosphonium hydroxide, tetraethylphosphonium hydroxide, and tetraphenylphosphonium hydroxide.

20: The process according to claim 16, wherein the catalyst component (C2) is selected from the group consisting of phosphoric acid, phosphonic acid, phosphinic acid, poly phosphoric acid, isopoly phosphoric acid, heteropoly phosphoric acid, etidronic acid, pamidronic acid, risedronic acid, zoledronic acid, clodronic acid, alendronic acid, and tiludronic acid.

21: The process according to claim 16, wherein the composition (A) comprises the catalyst system (CS) in an amount in the range of from 0.1 to 30 mol %.

22: The process according to claim 16, wherein the composition (A) comprises at least one monool (am).

23: The process according to claim 16, wherein the drying according to c) is carried out by converting liquid comprised in the gel into a gaseous state at a temperature and a pressure below a critical temperature and a critical pressure of the liquid comprised in the gel.

24: The process according to claim 16, wherein the drying according to c) is carried out under supercritical conditions.

25: The process according to claim 16, wherein the porous material is a thermal insulation material or a vacuum insulation panel.

26: The process according to claim 25, wherein the porous material is a component in an interior or exterior thermal insulation system.

27: The process according to claim 25, wherein the porous material is an insulation component in a thermal bridge.

28: The process according to claim 25, wherein the porous material is an insulation component in a refrigerator or freezer.

Description

EXAMPLES

1. Methods

[0451] 1.1 Determination of Thermal Conductivity [0452] The thermal conductivity was measured according to DIN EN 12667 with a heat flow meter from Hesto (Lambda Control A50).

[0453] 1.2 Solvent Extraction with Supercritical Carbon Dioxide [0454] One or several gel monoliths were placed onto sample trays in an autoclave of 25 l volume. Subsequent to filling with supercritical carbon dioxide (scCO.sub.2), the gelation solvent was removed (drying) by flowing scCO.sub.2 through the autoclave for 24 h (20 kg/h). Process pressure was kept between 120 and 130 bar and process temperature at 60° C. in order to maintain carbon dioxide in a supercritical state. At the end of the process, the pressure was reduced to normal atmospheric pressure in a controlled manner. The autoclave was opened, and the obtained porous monoliths were removed.

[0455] 1.3 Determination of Compressive Strength and E Modulus [0456] The compressive strength was determined according to DIN EN ISO 844 with 6% strain.

2. Materials

[0457] Component a1: Oligomeric MDI (Lupranat M200) having an NCO content of 30.9 g per 100 g in accordance with ASTM D-5155-96 A, a functionality in the region of three and a viscosity of 2100 mPa.Math.s at 25° C. in accordance with DIN 53018 (hereinafter “M200”) [0458] Component a2: 3,3′,5,5′-Tetraethyl-4,4′-diaminodiphenylmethane (hereinafter “M DEA”) [0459] Component a3: Ethane-1,2-diol (hereinafter: “MEG”) [0460] Component a4: Exolit® OP560 (hereinafter: “OP560”) [0461] Component a5: n-Butanol [0462] Component a6: Jeffcat Z-110 [0463] Catalysts: Tetrabutylammonium Hydroxide (TBA-OH) [0464] Tetrabutylphosphonium Hydroxide (TBP-OH) [0465] Phosphoric Acid (H.sub.3PO.sub.4) [0466] Etidronic acid (ETA)

3. Examples

[0467] Thermal conductivity values for all examples are shown in Table 2. Furthermore, data regarding the compressive strength and density are included for several examples.

[0468] 3.1 General Procedure for the Examples: [0469] In a polypropylene container, 32.00 g M200 were stirred in 146.67 g MEK at 20° C. leading 15 to a clear solution. Similarly, 5.33 g MDEA, 1.00 g OP560 and 2.67 g butanol as well as variable quantities MEG, water and Jeffcat Z-110 (see Table 2) were dissolved in 146.67 g MEK before a previously prepared solution containing C1 and C2 was added. [0470] The solutions were combined in a rectangular container (16 cm×16 cm×3 cm height) by pouring one solution into the other, which led to a homogeneous mixture of low viscosity. The container was closed with a lid and the 20 mixture was gelled at room temperature for 24 h. If possible, the resulting monolithic gel slab was dried through solvent extraction with scCO.sub.2 in a 25 l-autoclave leading to a porous material.

[0471] 3.2 Materials Used

TABLE-US-00001 TABLE 1 materials used. Jeffcat Example MEG Water Z-110 C1 C2  1 1.33 0.93 0 0.37 — (comparative) 43% TBA-OH/ water  2 1.33 0.93 0 0.39 — (comparative) 44% TBP-OH/ water  3 1.33 0.93 0 — 0.23 (comparative) 15% H3PO4/ water  4 1.33 0.93 0 — 0.26 (comparative) 27% ETA/ water  5 2.67 0.93 0 0.32 0.07 55% TBA-OH/ 49% H3PO4/ water water  6 2.00 0.40 0 0.24 0.04 55% TBA-OH/ 43% H3PO4/ water water  7 2.00 0.40 0 0.28 0.12 55% TBA-OH/ 14% H3PO4/ water water  8 2.00 0.40 0 0.32 0.07 55% TBA-OH/ 48% H3PO4/ water water  9 1.33 0.40 0.10 0.25 0.08 55% TBA-OH/ 45% ETA/ water water 10 1.33 0.40 0.10 0.35 0.08 55% TBA-OH/ 45% ETA/ water water 11 (WO2017 0* 0 0 1.33 0.33 125415) 55% K-sorbate/ 90% NEt3H (comparative) MEG octoate/MEG 12 0* 0 0.10 1.33 0.33 (comparative) 55% K-sorbate/ 90% NEt3H MEG octoate/MEG 13 0* 0.40 0 1.33 0.33 (comparative) 55% K-sorbate/ 90% NEt3H MEG octoate/MEG 14 0* 0.40 0.10 1.33 0.33 (comparative) 55% K-sorbate/ 90% NEt3H MEG octoate/MEG 15 1.33 0.40 0 0.25 0.08 (comparative) 55% TBA-OH/ 45% ETA/ water water 16 1.33 0 0.10 0.25 0.08 (comparative) 55% TBA-OH/ 45% ETA/ water water 17 0 0.40 0.10 1.33 0.08 (comparative) 55% K-sorbate/ 45% ETA/ MEG water 18 1.33 0.40 0.10 0.25 0.35 (comparative) 55% TBA-OH/ 85% NEt3H water octoate/water *MEG from C1 and C2 same amount as example with 1.33 g MEG.

4. Results

[0472]

TABLE-US-00002 TABLE 2 Compressive strength at 10% Density Thermal conductivity compression Example [kg/m.sup.3] [mW/(m*K)] [kPa]  1 Gel broken before supercritical drying (comparative)  2 Gel broken before supercritical drying (comparative)  3 Gel broken before supercritical drying (comparative)  4 Gel broken before supercritical drying (comparative)  5 120 16.9 453  6 115 17.7 460  7 125 17.1 433  8 128 17.3 407  9 127 16.8 461 10 128 16.7 339 11 121 17.3 506 (WO2017125415) (comparative) 12 Deformation and strong shrinkage (comparative) during supercritical drying 13 — 18.3 — (comparative) 14 — 18.0 — (comparative) 15 Gel broken before supercritical drying (comparative) 16 Strong shrinkage during supercritical drying (comparative) 17 Inhomogeneous gel (comparative) 18 — 17.4 — (comparative)

5. Abbreviations

[0473] OP560 Exolit® OP560 [0474] H.sub.2O Water [0475] M200 Lupranate M200 (polyisocyanate) [0476] MEG Ethane-1,2-diol [0477] MEK Methyl ethyl ketone [0478] MDEA 4,4′-Methylene-bis(2,6-diethylaniline)

LITERATURE CITED

[0479] WO 95/02009 A1 [0480] WO 2008/138978 A1 [0481] WO 2011/069959 A1 [0482] WO 2012/000917 A1 [0483] WO 2012/059388 A1 [0484] WO 2016/150684 A1 [0485] PCT/EP2017/05094 [0486] PCT/EP2017/050948 [0487] PCT/EP2018/069388 [0488] WO 2009/027310 A1 [0489] Polyurethane, 3.sup.rd edition, G. Oertel, Hanser Verlag, Munich, 1993 [0490] Plastics Additive Handbook, 5th edition, H. Zweifel, ed. Hanser Publishers, Munich, 2001