Process for producing porous materials
The present invention relates to a process for preparing a porous material, at least comprising the steps of providing a mixture (I) comprising a composition (A) comprising components suitable to form 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 obtained in step b), wherein the composition (A) comprises at least one compound (af) comprising phosphorous and at least one functional group which is reactive towards isocyanates. The invention further relates to the porous materials which can be obtained in this way and the use of the porous materials as thermal insulation material and in vacuum insulation panels, in particular in interior or exterior thermal insulation systems as well as in water tank or ice maker insulation systems.
1. A process for preparing a porous material, the process comprising:
reacting a composition (A) comprising a compound (af) comprising phosphorous and a functional group which is reactive towards isocyanates and a catalyst system (CS) as component (a0), in the presence of a solvent (B), to form a gel; and
drying the gel to form a porous material;
wherein
compound (af) is present in an amount which results in a phosphorous content in the porous material in a range of from 1 to 5% by weight,
wherein the compound (af) comprises at least one functional group comprising the phosphorous selected from the group consisting of a phosphonate, a phosphinate, a phosphite, a phosphonite, a phosphinite, and a phosphine oxide,
the composition (A) further comprises a polyfunctional isocyanate as a component (a1), and an aromatic amine as a component (a2), optionally water as a component (a3), and optionally a further catalyst as a component (a4),
the component (af) is used in an amount in the range of 1 to 5% by weight based on the sum of the weight of the components (a0) to (a4), and
the catalyst system (CS) comprising a catalyst component (C1) is selected from the group consisting of an alkali metal salt of a saturated monocarboxylic acid, an alkali metal salt of an unsaturated monocarboxylic acid, an earth alkali metal salt of a saturated monocarboxylic acid, an earth alkali metal salt of an unsaturated monocarboxylic acid, an ammonium salt of a saturated monocarboxylic acid, an ammonium salt of an unsaturated monocarboxylic acid, an ionic liquid salt of a saturated monocarboxylic acid with 1 to 20 carbon atoms, and an ionic liquid salt,
wherein said porous material has a water uptake of no more than 7 wt. %.
2. The process of claim 1 , wherein the catalyst system (CS) further comprises a carboxylic acid as a catalyst component (C2).
3. The process of claim 2 , wherein the catalyst component (C2) is at least one selected from the group consisting of a saturated monocarboxylic acid having 1 to 12 carbon atoms and an unsaturated monocarboxylic acid having 1 to 12 carbon atoms.
4. The process of claim 1 , wherein the composition (A) further comprises a monool (am).
5. The process of claim 1 , wherein the drying converts a liquid in the gel into the gaseous state at a temperature and a pressure below a critical temperature and a critical pressure of the liquid in the gel.
6. The process of claim 1 , wherein the drying is carried out under supercritical conditions.
7. A porous material obtained by the process of claim 1 .
8. A thermal insulation material or vacuum insulation panel, comprising:
the porous material of claim 7 .
9. An interior or exterior thermal insulation system, comprising:
the porous material of claim 7 .
10. An insulation of a thermal bridge, comprising:
the porous material of claim 7 .