styrene-butadiene rubber vs polyfoam

can someone explain to me the difference between styrene-butadiene rubber and polyfoam. Why is styrene-butadiene rubber referred to as synthetic latex but polfoam is well, polyfoam. I am most interested mostly to understand what Simbatex is. This synthetic latex they wont give me details on what its made from. I said is it polyfoam they said no. So would like to udnerstand how simbatex is different from polyfoam. Anyone have any idea? Thanks.

Hi hweywannaplay,

Welcome to the Mattress Forum! :slight_smile:

Here is some information about polyurethane foam here and here. In the simplest version, polyurethane foam (polyfoam) is isocyanate, polyol and water mixed, foamed and cured.

Latex in general is the most durable of all the foam materials (latex foam, memory foam, polyfoam) regardless of whether it is Dunlop or Talalay or is made from natural rubber, synthetic rubber, or a blend of both. There is more about the different types and blends of latex in post #6 here but the choice between different types and blends of latex is more of a preference and budget choice than a “better/worse” choice.

I know you didn’t ask about memory foam, but latex and memory foam are very different materials with very different properties. There is more about some of the differences between memory foam and latex in post #2 here.

Styrene Butadiene (SBR) is basically synthetic latex.You can read the Wikipedia description here.

The Simbatex layer on the top of the Simba mattress is a layer of synthetic (SBR) latex foam. I don’t have any other information about the product. Perhaps there is a member on the forum with more familiarity about the Simba mattress that can be of assistance, as the Simba website provides very little meaningful information about the specifics of the layers in their mattress.

Phoenix

Thanks for that. This is why i am confused, i always thought of polyfoam as synthetic latex. Now i hear that synthetic latex is styrene-butadiene rubber. I thought latex was 100% natural and came from the rubber tree, therefore im confused how anything can be synthetic latex. Also how the propertied between styrene-butadiene rubber and polyfoam differ? Thanks for your time.

Hi heywannaplay,

As you found out, styrene-butadiene (SBR) is a type of latex, not a polyfoam.

I’m glad I could help clear up your confusion. :lol:

Phoenix

sorry but i just understand. Latex is a 100% natural product from the rubber tree. Anything synthetic then cant be latex? Therefore why is tyrene-butadiene rubber said to be synthetic latex but polyfoam not said to be synthetic latex? What is the difference between the two that makes it ok to call one a synthetic latex but not the other? At what point is something synthetic latex but at another point not a synthetic latex but a polyfoam?

Hi heywannaplay,

Please go back and read the previous reply I offered you in post #2 in this thread, specifically the links to post #6 and the SBR link.

The latex component (rubber particles dispersed in water) of latex foam can be sourced:

  1.        As [url=https://mattressunderground.com/our-articles/latex-pros-and-cons.html]natural latex [/url]from the Hevea Brasiliensis tree (rubber tree) – What we call NR, or;
    
  2.        As man-made latex – [url=https://mattressunderground.com/our-articles/latex-pros-and-cons.html]Styrene-Butadiene[/url], what we call SBR. 
    

When making latex foam, it can be made via two processes: Dunlop or Talalay. To keep it simple, I’ll describe the Dunlop process here.

To make “rubber foam” (what we call latex foam), you would take an amount of the liquid latex component (either some from the Hevea tree (NR), some from the man-made (SBR) or a mixture of both) and mechanically beat it mix it and mix it with air to get it to foam. The you would mix that with a gelling agent like sodium silicoflouride, which in the presence of zinc oxide sets the foam into gel in a mold, into which this is poured. The gelled foam is then vulcanized in steam, stripped from the mold, washed and dried. A secondary gelling agent is usually added to prevent premature collapse and reduce gelling time. That’s it, in a very simplified form.

The resulting latex foam rubber would be called 100% NR if the liquid latex used to make the foam was all from the Hevea tree. If the latex foam rubber used liquid latex in the process that was all man-made, it would be called 100% SBR latex. If the latex foam rubber used a portion of each liquid latex from the Hevea tree and a portion of man-made liquid latex, it would be termed SBR/NR latex rubber foam.

You can see more about the differences between SBR and NR rubber in post #2 here.

You can read more about synthetic continuous pour Dunlop latex in post #2 here and there is more about natural rubber and synthetic rubber in post #2 here.

You can read more about Dunlop (of either type) vs Talalay latex in post #7 here.

You can read a bit more about organic Dunlop in post #6 here.

Polyurethane foam is not latex foam, as I mentioned previously.

Phoenix