PHENOLIC FOAMS WITH BLOWING AGENT 1,1,1,4,4,4-HEXAFLUORO-2-BUTENE
Disclosed are foam compositions and processes to form closed-cell phenolic foams. The foams comprises a continuous polymeric phase defining a plurality of cells, wherein the continuous polymeric phase comprises a phenol-formaldehyde resole derived from a phenol and formaldehyde, and wherein the plurality of cells comprises a plurality of open-cells and a plurality of closed-cells with an open-cell content measured according to ASTM D6226-5, of less than 50%. The foam composition also comprises a discontinuous phase disposed in at least a portion of the plurality of closed-cells, the discontinuous phase comprising 1,1,1,4,4,4-hexafluoro-2-butene.
1 . A foam comprising:
(a) a continuous polymeric phase defining a plurality of cells, wherein:
the continuous polymeric phase comprises a phenol-formaldehyde resole derived from a phenol and formaldehyde, and
the plurality of cells comprises a plurality of open-cells and a plurality of closed-cells with an open-cell content measured according to ASTM D6226-5, of less than 50%; and
(b) a discontinuous phase disposed in at least a portion of the plurality of closed-cells, the discontinuous phase comprising 1,1,1,4,4,4-hexafluoro-2-butene.
2 . The foam of claim 1 , wherein the phenol-formaldehyde resole is derived from a phenol and formaldehyde present as reactants in a weight ratio in the range of 1:0.3 to 1:1.6.
3 . The foam of claim 1 , wherein the open-cell content measured according to ASTM D6226-5, is less than 40%.
4 . The foam of claim 1 , wherein the open-cell content measured according to ASTM D6226-5, is less than 30%.
5 . The foam of claim 1 , wherein the foam has a density in the range of 10-500 kg/m 3 .
6 . The foam of claim 1 , wherein the foam has a density in the range of 20-100 kg/m 3 .
7 . The foam of claim 1 , wherein the foam has a thermal conductivity in the range of 0.015-0.035 W/m·K.
8 . The foam of claim 1 , wherein the cell has an average size of less than 500 microns.
9 . The foam of claim 1 , wherein at least 80% of the cells has an average size of less than 300 microns.
10 . The foam of claim 1 , wherein the phenol-formaldehyde resole is derived from a phenol, formaldehyde, and a reactant comprising water, methanol, ethylene glycol, polyol, propane diol, furfural, furfuryl alcohol, urea, resorcinol, or mixtures thereof.
11 . The foam of claim 1 , wherein the phenol-formaldehyde resole is derived from a phenol, formaldehyde, and urea, and wherein the phenol and urea are present in a weight ratio of 1:0.005 to 1:0.05.
12 . The foam of claim 1 , wherein the foam has a limiting oxygen index (LOI) of at least 30, measured according to ASTM-D2863.
13 . An article comprising the foam of claim 1 .
14 . The article of claim 13 comprising a sandwich panel structure, wherein the sandwich panel structure comprises the foam disposed between two similar or dissimilar non-foam materials.