Polymeric composition acting as barrier to noxious agents
The present application is directed to a novel composition which acts as a barrier to noxious agents while showing enhanced moisture vapour permeability and resistance to water and laundering.
1. A composition for protection against harmful or noxious agents comprising a mixture of:
a) from 5 to 80% by weight of a polyvinyl acetate polymer or copolymer;
b) from 5 to 20% by weight of an polyethylenimine;
c) from 0.1 to 10% by weight of a surfactant;
d) from 0.1 to 10% by weight of an epoxy resin or of a cross-linking agent;
e) from 0.5 to 10% by weight of a defoamer agent;
f) from 10 to 90% by weight of water.
2. The composition of claim 1 further comprising:
g) from 0 to 20% by weight of a polyvinyl alcohol;
h) from 0 to 5% by weight of one or more metal salts or oxides.
3. The composition of claim 1 wherein the polyvinyl acetate is ethylene vinyl acetate.
4. The composition of claim 1 wherein the polyvinyl acetate is present in an amount of 5 to 20% by weight.
5. The composition of claim 3 wherein the ethylene vinyl acetate is present in an amount of 20 to 50% by weight.
6. The composition of claim 2 wherein the metal salts or oxides are selected from the group consisting of aluminum chloride, zinc oxide, copper oxide, magnesium oxide, calcium oxide, calcium carbonate and silver nitrate.
7. Process for the preparation of a laminated support comprising:
a) mixing together from 5 to 80% by weight of a polyvinyl acetate polymer or copolymer, from 5 to 20% by weight of an polyethylenimine, from 0 to 20% by weight of a polyvinyl alcohol and from 10 to 90% by weight of water at a temperature of 80 to 100° C.;
b) adding from 0.1 to 10% by weight of a surfactant, from 0.1 to 10% by weight of an epoxy resin or of a cross-linking agent, from 0.5 to 10% by weight of a defoamer agent, and from 0 to 5% by weight of one or more metal salts or oxides;
c) casting said composition on a solid support to yield a laminated support;
d) curing said laminated support at a temperature in the range of 100 and 220° C.
8. The process of claim 7 wherein the laminated support is cured at a temperature in the range of 130 to 200° C.
9. The process of claim 7 wherein the laminated support is cured at a temperature in the range of 130 to 170° C.
10. The process of claim 7 wherein the solid support is selected from the group consisting of ePTFE, polyurethane, poyamide, polyester or a blend of two or more thereof.
11. The process of claim 7 further comprising the step of:
e) securing the laminated support to a second solid support.
12. The process of claim 11 wherein the second solid support is selected from the group consisting of ePTFE, polyurethane, polyamide polyester or a blend of two or more thereof.
13. The process of claim 11 wherein the second solid support is secured to the laminated support by adhesive means.
14. The process of claim 7 wherein the composition is cast onto the solid support in a thickness of between 5 to 100 μm.
15. The process of claim 14 wherein the thickness is between 30 to 70 μm.
16. The process of claim 15 wherein the thickness is between 40 to 60 μm.
17. The process of claim 16 wherein the thickness is 50 μm.
18. Laminated support comprising one or more layers of a composition of any one of claims 1 to 3 or 4 to 6 .