How do you increase the density of PU foam?

shows that the density of the PU foam increases with increasing part B (diisocyanate) of the PU main constituents and vice versa.

What is gel time in foam?

gel time specifies the time period upto which the adhe- sive formulation remains in the flowing state, thus, indicates its suitability of application between the substrate. The gel time of different PU adhesive formulations are reported in Table 2.

What does cream time mean?

The cream time is defined as time that mixture need after mixing polyol with isocyanate until the reaction started. At this point mixture started to appear as creamy mixture due to the fine bubble started to be produced and apparently occurred.

What is the density of polyurethane?

PU FOAM DENSITY CONSIDERATIONS Foam densities range from approximately 2 to 60 lbs. per cubic foot (48 to 961 kg/m3). Unlike thermoplastic foams (PVC, SAN,), the unit cost of polyurethane foam increases in a linear fashion with density, so a 20-lbs. -per-cubic foot PU foam will be approximate twice the cost of a 10-lb.

What is m3 foam?

In mattress terms, it means the mass of a cubic metre section of a mattress measured in kilograms per cubic metre (kg/m3). Say, if a foam is 50kg/m3, that means each cubic metre of the foam weighs 50 kg.

What is cream time polyurethane?

The cream time is the time when the liquid PU starts to expand, due to the gas reaction. Then, it comes the crosslinking of the foam (which speed can be measured by the so called string time) and the finish of the expansion (measured by the so called rise time).

How do you reduce the viscosity of polyurethane?

The viscosity of aromatic polyester polyols and polyether polyols is reduced by adding 5\% to 15\%, based on the weight of the polyol, of a cyclic organic viscosity reducing agent selected from propylene carbonate, ethylene carbonate, mixtures of ethylene carbonate and propylene carbonate, and caprolactone.

Can you smooth expanding foam?

Expanding foam is a can of liquid that quickly expands and hardens once sprayed. Once dried, it can be trimmed, sanded and painted.

What is gel time for epoxy?

Gel time is the time it takes for a mixed resin system to gel or become so highly viscous that it can no longer be considered workable or able to be handled.

Is 32 density foam good?

High-density foam means higher quality as it has a strong cell structure. Consumers should check the specifications of the foams used. On a standard basis for the Indian market, PU foams should have 32 to 40 density, memory foam should have 50 to 60 density and Latex should have 55 to 65 density.