Polymeric compositions as pour point depressants for crude oils
Multilayered composite materials comprising as components: (A) a water vapor permeable plastics foil, (B) optionally at least one bonding layer and (C) a polyurethane layer with capillaries passing through the entire thickness of the polyurethane layer.
1. A composite material comprising:
a plastic foil having a water vapor permeability greater than 1.5 mg/cm 2 h, measured according to German standard specification DIN 53333, the polymer foil selected from self-supporting films/sheets of fluorinated polymers and of chemically modified polyesters; and
a polyurethane layer with capillaries that extend through the entire thickness of the polyurethane layer, the polyurethane layer prepared from a dispersion having a solids content of from 10% to 50%, based on the total weight of the dispersion, wherein the polyurethane dispersion comprises;
a soft polyurethane (PU1),
a hard polyurethane (PU2) with a Shore A hardness of greater than 60 and less than 100, and
a crosslinker, and PU1 and PU2 prepared from isophorone diisocyanate.
2. The composite material according to claim 1 , further comprising a bonding layer of a cured organic adhesive.
3. The composite material according to claim 2 , further comprising an interlayer selected from leather, textile, paper or batt materials.
4. The composite material according to claim 3 , wherein the interlayer is in direct contact with the polyurethane layer, and the bonding layer is positioned between the interlayer and the plastic foil.
5. The composite material according to claim 1 , wherein the plastic foil is a fluorinated polymer that includes polytetrafluoroethylene.
6. The composite material according to claim 1 , wherein the polyurethane layer has an average thickness in the range from 25 μm to 80 μm.
7. The composite material according to claim 1 , wherein the crosslinker is of formula 1a or formula 1b
wherein R 3 , R 4 and R 5 , are each independently, A-NCO,
A is a linker with 2 or 20 carbon atoms selected from arylene, optionally substituted with one to four C 1 -C 4 alkyl groups, or alkylene.
8. The composite material according to claim 1 , wherein the polyurethane dispersion further comprises a silicone compound having on average one to four carboxylic acid groups.
9. The composite material according to claim 1 , wherein the polyurethane dispersion further comprises a diamine with a carboxylic acid or sulfonic acid group.
10. The composite material according to claim 1 , wherein the PU1 and PU2 each are prepared from isophorone diisocyanate with a greater mole percentage of isophorone diisocyanate present in PU2 than PU1.
11. A process for producing the composite material according to claim 1 , the process comprising:
forming the polyurethane layer with the aid of a pre-heated silicone mold;
applying at least one organic adhesive to a surface of the water vapor permeable plastic foil and/or to a surface of the polyurethane layer; and
bonding the polyurethane layer pointwise, stripwise or areawise to the water vapor permeable plastic foil.
12. The process according to claim 11 , wherein the silicone mold includes a surface structured made by laser engraving.
13. A packaging material consisting of the composite material according to claim 1 .
14. An apparel piece including the composite material according to claim 1 , the apparel piece being a jacket or shoe upper.