By 120,000 Mrad there was some loss of definition in the diffraction patterns, while by 680,000 Mrad they showed a mixture of a non-crystalline but partly ordered structure and completely amorphous . The effects of high doses of radiation on different bonds is different, and this becomes relevant in the formation of the conjugated double bonds that produce the yellow to brown colours. Even at comparatively low doses the factors that become of importance can be observed. Again, C-O bonds show little or no tendency to reform after rupture. This means that some of the hydrogen is likely to diffuse away as hydrogen gas, while there will be a surplus of free carbon ends.
Stability is restored by the formation of double bonds.
With increasing radiation doses, and increasing loss of hydrogen, the number of conjugated double bond systems increases. So, also, the depth of colour increases with increasing radiation dose. With the passage of neutrons a certain number of tritium atoms would be formed. The soft beta radiation that they emitted would help to stabilize the structure. The former happened in an instant, and so the oxygen in the air did not have time to induce the chemical changes.