budgy wrote:
I don't want to nitpick but in the interest of disclosure...you said that synthetic latex is the same chemical compound as natural latex...this is false.
What the mattress industry refers to as synthetic latex is called Styrene Butadiene, natural rubber or natural latex is made of isoprene (methyl butadiene base)...they are two completely different polymer materials with different properties. It may sound like a small difference...but chemistry is complex...consider that two molecules of oxygen binded together gives us oxygen in the form we breathe it in and gives us life. 3 molecules of oxygen gives us ozone and can take your life away.
No tires, including nascar tires are pure natural rubber, there are all sorts of other chemicals used that determine the hardness and elasticity of the end product; even in passenger car tires there are different polymer materials used than just NR or SBR, they all give different properties. You would be correct if you mean that the only polymer material that is used in a race cars tires is real natural rubber, ironically for all the complete opposite reasons the mattress industry tells us that synthetic blends are better (durability, consistency) are the reasons that only pure natural rubber is used in race car tires and airplane tires...safety. Natural rubber is actually more stable than any other polymer material around...its only weakness compared to SBR is its resistance to petrochemicals over time...this is the only reason SBR is used in passenger car tires, the long term exposure to gasoline vapours and oils that are in pavement and all over our roads is really hard on natural rubber. These are not issues that a mattress has to deal with thankfully. When it comes to compression set resistance (resistance to hysteresis), overall elasticity and elongation qualities, natural rubber tree milk outperforms other polymer materials dramatically. Where the consistency issues actually come from are mostly out of date manufacturing techniques, or due to being long distance from rubber plantations, perhaps even buying hevea milk from many different regions around the globe and using it all in the same batch; its hard to be consistent making latex this way without using SBR.
You are totally correct... I was attempting to simplify the details, but in retrospect, it is the differences that create different response to the sleeper. Thanks for the clarification (and extra info I did not know the actual details of!), Budgy. Have a great day!