Barrier, construction article and method of manufacture thereof
A barrier and method of manufacture thereof is provided. The barrier is suitable for enhancing the reaction to fire of structural elements such as construction boards.
1. A barrier comprising a cured phosphate composition and a glass fibre scrim, wherein the cured phosphate composition is impregnated within the glass fibre scrim and further wherein the glass fibre scrim has a mesh size in the range of from 0.5 mm×0.5 mm to 9 mm×9 mm and further wherein the glass fibre scrim is capable of reducing the pH of demineralised water having a pH of 7 to a pH 6.3 or lower, when assessed in accordance with ISO 3071:2005, said barrier having a thickness of at least 1 mm;
the cured phosphate composition is formed from a curable composition comprising:
a phosphate selected from the group consisting of: phosphoric acid, phosphoric acid salts and combinations thereof,
a metal oxide, a metal silicate, and water,
where the weight ratio between the phosphate and the metal oxide is between about 3:1 and 1:1.
2. The barrier according to claim 1 , wherein the phosphate is present in an amount of from about 10 to about 45 weight percent based on the total weight of the curable composition.
3. The barrier according to claim 1 , wherein the metal oxide is present in an amount of from about 5 to about 35 weight percent based on the total weight of the curable composition.
4. The barrier according to claim 1 , wherein the metal silicate is present in an amount of from about 1 to 15 weight percent based on the total weight of the curable composition.
5. The barrier according to claim 1 , wherein the phosphate is mono-potassium phosphate.
6. The barrier according to claim 1 , wherein the metal oxide is magnesium oxide.
7. The barrier according to claim 1 , wherein the curable composition comprises mono potassium phosphate in an amount of from about 24 to about 32 weight percent, magnesium oxide in an amount of from about 22 to 28 weight percent, aluminium silicate or calcium silicate in an amount of from about 2 to 5 weight percent, and water in an amount of from about 20 to 40 weight percent, based on the total weight of the curable composition.
8. The barrier according to claim 1 , wherein the curable composition is a two-part (2K) composition.
9. The barrier according to claim 1 , wherein the curable composition further comprises an adhesion promoter.
10. The barrier according to claim 9 , wherein the adhesion promoter is present in an amount of from about 0.01 wt % to about 5 wt % based on the total weight of the curable composition.
11. The barrier according to claim 9 , wherein the adhesion promoter is selected from isopropanol, limonene, sodium silicate, acrylic-styrenic co-polymer or combinations thereof.
12. The barrier according to claim 1 , having a thickness of about 1 mm and a weight of about 1.3 to about 1.5 kg/m 2 .
13. A construction article comprising a structural element having a barrier according to claim 1 applied thereto.
14. The construction article according to claim 13 , wherein the structural element comprises wood, fibreboards, particleboards, medium density fibreboard (MDF), oriented strand board (OSB), gypsum, a vacuum insulation panel and/or foam.
15. The construction article according to claim 13 , and having at least a B classification according to EN13501, or having an A2 or an AI classification according to EN13501.