Photopolymerization of Disordered Solid Acetaldehyde at Crygenic Temperature

Article abstract of DOI:10.1021/j100182a087

Binary solid solutions of 5percent chlorine in acetaldehyde were formed by vapor deposition onto the surface of a CsI optical window at 77 and 10 K.Laser photolysis of the low-temperature films at 308 nm induces a chemical reaction forming acetyl chloride and oligomeric acetaldehyde as the major products.The average chain length of the oligomer is 8.1 +/- 1.1 monomer units for the 77 K experiments.Films deposited and photolyzed at 10 K exhibit smaller chain lengths which grow upon warming to temperature above 40 K.The photochemical behavior of this system parallels that of well-studied formaldehyde polymerization reaction in the solid state in which the principal barriers to chain propagation are spatial and orientational discordering of molecules in the solid lattice.