2,4-Hexadiyne-1,6-diol Bis(azobenzene-4-sulfonate) (cas# 78991-75-0) is a diacetylene with chromophoric substituent groups. 2,4-Hexadiyne-1,6-diol Bis(azobenzene-4-sulfonate) readily undergoes thermal or radiochemical polymerization, with the colour of the polymer being dependant on its length.