Water-tight breathable membrane

Abstract

The present invention relates to shaped bodies comprising a composition (Z1), wherein said composition comprises at least one polymer having an elongation at break of >30% and at least one porous metal-organic framework material, to processes for producing shaped bodies of this kind and to the use of a composition (Z1) comprising at least one polymer having an elongation at break of >30% and at least one porous metal-organic framework material for production of a film, membrane or laminate having a water vapor permeability according to DIN 53122 at 38 C./90% rel. humidity of greater than 1000 g/(m.sup.2*d), based on a film thickness of 10 m.

Claims

1. A shaped body, comprising a composition (Z1), wherein said composition (Z1) comprises: at least one polymer having an elongation at break of >30%, determined according to ISO 527-1; and (ii) at least one porous metal-organic framework material, wherein: a portion of the porous metal-organic framework material in the composition (Z1) ranges from 0.1% to 10% by weight; the porous metal-organic framework material has an average pore diameter in the range from 0.2 to 4 nm; the porous metal-organic framework material comprises zinc, magnesium or aluminum as metal; the polymer is selected from the group consisting of a thermoplastic polyurethane, a polyester, a polyether, a polyetherester, a polyketone, a polyethersulfone, a polysulfone, a polyetherimide, a polyamide and a polyolefin; and wherein the shaped body is a film, membrane or laminate and the film, the membrane or the laminate has a thickness in the range from 80 to 500 m.

2. The shaped body according to claim 1, wherein the shaped body is a membrane.

3. The shaped body according to claim 1, wherein the shaped body is obtained by an extrusion process.

4. A process for producing a shaped body, the process comprising producing a shaped body from a composition (Z1) by an extrusion method, an injection molding method, a casting method, a blowing method, a sintering method, or a lamination method, wherein: the composition (Z1) comprises: (i) at least one polymer having an elongation at break of >30%, determined according to ISO 527-1, and (ii) at least one porous metal-organic framework material; a portion of the porous metal-organic framework material in the composition (Z1) ranges from 0.1% to 10% by weight; the porous metal-organic framework material has an average pore diameter in the range from 0.2 to 4 nm; the porous metal-organic framework material comprises zinc, magnesium or aluminum as metal; the polymer is selected from the group consisting of a thermoplastic polyurethane, a polyester, a polyether, a polyetherester, a polyketone, a polyethersulfone, a polysulfone, a polyetherimide, a polyamide and a polyolefin; and wherein the shaped body is a film, membrane or laminate and the film, the membrane or the laminate has a thickness in the range from 80 to 500 m.

5. The process according to either of claim 4, wherein the shaped body is produced by an extrusion method.

6. The shaped body according to claim 1, wherein the film, the membrane or the laminate has a water vapor permeability according to DIN 53122 at 38 C. and 90% relative humidity of greater than 1000 g/(m.sup.2*d), based on a film thickness of 10 m.

7. The shaped body according to claim 1, wherein the film, the membrane or the laminate has a water vapor permeability according to DIN 53122 at 38 C. and 90% relative humidity of greater than 1000 g/(m.sup.2*d), based on a film thickness of 10 m, and a watertightness of 0.2 bar, measured according to DIN EN 20811:1992.

Description

EXAMPLES

1. Starting Substances

(1) Starting substances according to table 1 below were used:

(2) TABLE-US-00001 TABLE 1 starting substances Name Chemical composition Source Iso 4,4-Methylene diphenylene BASF diisocyanate Polyol1 Polytetrahydrofuran, Mn.sup.1): ~1000, BASF OH number: 112.2 Polyol2 Polytetrahydrofuran, Mn.sup.1): ~2000, BASF OH number: 56 KV Butane-1,4-diol, chain extender BASF AO Antioxidant BASF GL Amide wax Croda .sup.1)Mn is the number-average molecular weight

2. Provision of a Thermoplastic Polyurethane

2.1 TPU1

(3) 612 g of Polyol1 and 59.4 g of KV were weighed out in a 2 L tinplate bucket and heated up to 80 C. Subsequently, 10 g of AO were added while stirring at 220 rpm. After a stirring step for 2 min for homogenization, 318.4 g of Iso were added to the solution, which was stirred (45 s) until the solution had reached a temperature of 110 C. The reaction mixture was then poured into a flat dish and kept at 125 C. on a hotplate for 10 min. Thereafter, the resultant slab was heat-treated in a heating cabinet at 100 C. for 24 h.

2.2 TPU2

(4) 344.1 g of Polyol1, 344.1 g of Polyol2 and 45.3 g of KV were weighed out in a 2 L tinplate bucket and heated up to 80 C. Subsequently, 10 g of AO and 0.5 g of GL were added while stirring at 220 rpm. After a stirring step for 2 min for homogenization, 256 g of Iso were added to the solution, which was stirred (45 s) until the solution had reached a temperature of 110 C. The reaction mixture was then poured into a flat dish and kept at 125 C. on a hotplate for 10 min. Thereafter, the resultant slab was heat-treated in a heating cabinet at 100 C. for 24 h.

(5) The material thus produced was comminuted in a mill to give a pourable granular material, dried again and dispensed into aluminum-coated PE bags for further use.

2.3 LDPE (Lyondell-Basell NA 940000) and Thermoplastic Polyurethane TPU2 Were Processed Together with the MOFs Used by Means of Film Extrusion to Give the Test Films

(6) The films were produced using an Xplore mini laboratory extruder (Microcompounder MC15 with CFPL microcast film attachment). The MOFs were premixed in powder form with the polymer pellets in the amounts specified and then extruded to give the film.

(7) Alternatively, the TPUs were used to produce a 10% solution in THF, the MOFs were dispersed in this solution and cast films were produced by means of a coating bar. The tests described below were conducted on these films.

(8) The MOFs used were Basolite A520 (Al fumarate) and Z1200 (Zn 2-methylimidazolate, Lit. ZIF-8). Al fumarate is a hydrophilic MOF having a pore size of 11.5 A. ZIF-8 is notable for its hydrophobic properties, with a pore size of 8 A and a pore opening of 3.4 A.

(9) Basolite A520 was produced according to example 2 of U.S. Pat. No. 8,524,932. Basolite Z1200 and Basosive M050 are commercially available from Sigma Aldrich.

3. Experiments with PE Film (Thickness 33-49 m)

(10) H2O permeation was measured at 23 C., 85% RH according to ASTMF-1249. The results are collated in table 2.

(11) TABLE-US-00002 TABLE 2 Transmission Permeability Thickness rate (g m/m.sup.2/ Material (m) (g/m.sup.2/day) day/85% RH) Comparative examples LDPE with no addition 44.8 2.02 91.4 47.1 1.88 86.9 Examples LDPE + 5% by wt. of 36.7 4.45 159 Basolite A520 MOF LDPE + 5% by wt. of 33.0 4.76 149 Basolite A520 MOF LDPE + 7.5% by wt. of 49.2 4.54 216 Basolite A520 MOF LDPE + 7.5% by wt. of 47.1 4.25 190 Basolite A520 MOF

(12) All films are watertight (water column 2000 mm, measured according to DIN EN 20811:1992, and also ISO 811). The addition of the MOFs increases the water vapor permeability by about a factor of 2.

4. Experiments with TPU Film Made from TPU1 and TPU-2 (Thickness 50-180 m)

(13) H2O permeation was measured at 38 C., 90% RH according to DIN 53122. The results are collated in table 3.

(14) TABLE-US-00003 TABLE 3 Transmission Permeability Thickness rate (g m/m.sup.2/ Material (m) (g/m.sup.2/day) day/90% RH) Comparative example TPU film with no addition 50 822 41000 Examples TPU1 + 1% by wt. of A520 MOF 70 944 66100 TPU1 + 2% by wt. of A520 MOF 90 942 84700 TPU1 + 5% by wt. of A520 MOF 120 1384 166100 TPU1 + 10% by wt. of A520 180 2238 402800 MOF TPU2 + 0.25% by wt. of MOF 70 989 69200 Z1200 TPU2 + 1% by wt. of MOF 80 963 77000 Z1200 TPU2 + 2% by wt. of MOF 100 958 95800 Z1200 TPU2 + 5% by wt. of MOF 100 1011 101100 Z1200

(15) All films are watertight (water column 2000 mm, measured according to DIN EN 20811:1992, and also ISO 811). The specimens with 5+10% A520 were only watertight to a limited degree. The addition of the MOFs increases the water vapor permeability by about a factor of 3.