Memory foam
From Plastics Wiki, free encyclopedia
Memory Foam is made from polyurethane with additional chemicals that add to its viscosity level, thereby increasing the density of the foam. It is often referred to as visco-elastic polyurethane foam. Depending on the chemicals used and the overall density of the foam, it can be firmer in cooler temperatures and softer in warmer environments. Higher density memory foam will react with body heat and allow it to mould itself to the shape of a warm body within a few minutes. However, a lower density memory foam is pressure-sensitive and will mould more quickly to the shape of the body. The example often used for a demonstration of its properties, is a hand pressed into the foam and then removed, leaving a clear impression of the hand in the foam.
Memory Foam was originally developed for use in the space program. The hope was that, because of its ability to distribute pressure across the entire surface, it could ease the pressure of extreme G-forces.
While memory foam was never used in the space program, it was subsequently used in medical applications, for example when a patient suffered from pressure sores or had to be bed-bound for a long period. It was initially too expensive for general use.
In recent years visco-elastic memory foam has become cheaper to produce and is now widely available for the home. Its most common domestic applications are mattresses, pillows and mattress toppers (also known as mattress pads).
A memory foam mattress is usually denser than an ordinary foam mattress. This makes it more supportive – but also heavier. It is often seen as a good compromise between the comfort of a soft mattress and the supportiveness of a firm one.
When new, memory foam often gives off a distinct chemical odour which many people find unpleasant. This fades with airing; however, some people remain sensitive to it.
Tempur-Pedic was the first large memory foam distributor, and its popularity today can be attributed to Tempur-Pedic.

