SOLID-STATE POLYMERIZATION OF DIACETYLENES.

Abstract

A review is presented of the solid-state polymerization process. The polymerization reaction is accompanied by dramatic changes in optical properties. The diacetylene monomer is colorless with an absorption onset near 300 nm, dependent on the extent to which the absorption of the R group interferes with that of the diacetylene moiety. The polymer, with its fully conjugated pi -electron system, absorbs strongly in the visible region and typically has an absorption peak at about 620 nm. Quantum yield for photopolymerization vary widely. The quantum yield can be expressed as the produce of two terms, nq, where n is the chain-propagation length and q is the chain-initiation probability; nq is the number of monomer units polymerized per absorbed photon.