Heat Shrink technology is based on selective and controlled with crosslinking of molecular chains. Crosslinking can be induced either by chemical means or by irradiating the product by an electron beam.

The formation of links between molecular chains is called crosslinking. A direct consequence of crosslinking is that the relative position of each molecule is fixed with the respect to its adjacent molecules. The fixing of the relative position of every molecule in the crosslinked molecular structure amounts to the material achieving "shape memory".

The crosslinking material is characterized by strong binding forces which does not flow on exposure to heat as the links between molecular chains holds the chains together. Beyond a certain temperature called the crystalline melting temperature, the crystals disappear and the material becomes soft and malleable.

This effect makes the material to shrink back to its original shape and profile on application of heat more than its crystalline temperature.