Filter Foam

New England Foam supplies, converts & fabricates the following types of filter foam:

Polyester (Ester)
- Largest sheet size = 48” x 118″
  - UL94/HF-1 available
    - 10 PPI Data
    - 20 PPI Data
    - 80 PPI Data
    - 90 PPI Data
Polyether (Ether)
- Largest sheet size = 48” x 118”
  - UL94/HF-1 available
    - 10 PPI Data
    - 20 PPI Data
    - 30 PPI Data
    - 40 PPI Data
    - 50 PPI Data

Characteristics

Filter foam, also known as reticulated foam, is a porous, low-density type of polyurethane foam with an open cell structure. Filter foam has a near-infinite amount of applications due to the following characteristics:

Compressibility
Cushioning
Fluid and Flow Liquid
Flexibility
Light-weight

Fabrication Available

Filter foam is the ideal material for applications where porosity, surface area & low-density are important for success.

In addition to fabricating filter foam products to custom designed specifications, New England Foam stocks filter foam in buns, in porosities ranging from 10 PPI or pores per inch (coarse) to 10 PPI (fine) & those colors most requested: charcoal (black) & white. 90 PPI is also available

Additional porosities & colors are available upon request, as well as Underwriters Laboratory (UL) compliant filter foam.

Cell Structure

Filter foam operates as a depth-loading filter, as opposed to a surface-loading filter, essentially trapping dust particles within its cells.

The cell structure of filter foam is remarkable in that each cell has a dodecahedron shape (12 sided), the cell’s walls or “struts” are comprised entirely of organic polymers (polyurethane, polyether, polyester) & the empty space or “windows,” between each strut, comprise 95% – 98% of the filter foam’s mass.

The size, shape and distribution of cells within filter foam can be manipulated during manufacture to provide precisely the desired porosity level, measured in PPI or pores per inch.

Polyester Filter Foam vs. Polyether Filter Foam

In applications where the filter foam will come into contact with a water-based solution, the filter foam should be manufactured with polyether-based polyols.

In applications where the filter foam will come into contact with gases, such as oxygen, nitrogen chemicals, carbon dioxide, the filter foam should be manufactured with polyester-based polyols.

Manufacturing

Filter foam can be manufactured using a thermal process where a preformed block of conventional polyurethane foam undergoes the removal of space from between each cell wall or “strut.”

Penetrating the internal structure of the filter foam with a combustible gas, such as hydrogen, & then igniting the gas in a controlled explosion accomplishes the removal of the thin layer of foam between each cell’s membrane.

The result is freshly manufactured filter foam that is perfectly porous & ready for further fabrication.

It is during this manufacturing process that flame retardant additives can be introduced to the filter foam to meet various fire code standards.

UC94/HF1 UV Coating is available.