The Characteristics of Memory Foam

Memory foam is an increasingly popular mattress filler. So, what are the characteristics of memory foam?

Memory foam differs from traditional mattress materials in that it is completely homogeneous - the same throughout. There are no springs or stuffing to shift positions and escape from the enclosing material. The foam is expanded polyurethane, which is somewhat akin to the expanded polystyrene used in packaging and take-away coffee cups. Unlike expanded polystyrene, however, it cannot be compressed to a near solid state. It will, after compression, regain its original shape; but, depending on the details of its manufacture, this will take varying periods of time.

Commonly, surfactants, of which washing-up liquid is an everyday example, are used to regulate the size of the cells (bubbles) within the foam. This allows for a variety of foam densities to be produced, and therefore gives the consumer a range of memory foam mattresses of differing firmness to choose from.

A particular characteristic of foam density is the speed with which its original shape can be restored, and to what extent it can be compressed. For example, a high density memory foam will be more difficult to compress than a low density memory foam. This means that if you want a mattress that will rapidly fashion itself to your bodily contours, a low density memory foam may be best.

On the other hand, whilst a high density foam is initially less pressure sensitive than a low density foam, i.e. less likely to deform under the weight of the slumberer, it will, nevertheless, respond to body heat and mould to the sleeper's body as it warms. This gives a slower response than that of the lighter density foam, but it means that once that desired sleeping position has been found, it will gradually, within a few minutes, respond to the sleeper's weight.

An advantage of a temperature sensitive response is that, whilst the upper layers of the mattress will deform in response to temperature, the underlying areas, which will be unaffected by body temperature as a result of the foams insulating properties, will not. This gives a gradation of firmness from the top down, and therefore confers upon the foam, both support and responsiveness.

Hollie Wilcox is writing on behalf of www.memoryfoammattresses365.co.uk to provide you with the latest information regarding memory foam mattresses .