Thermal and Photoinduced Polymerization of Thin Diacetylene Films. 1. Phthalimido-Substituted Diacetylenes

Abstract

A series of phthalimido-substituted (Pht) diacetylenes with the structure Pht-(CH2)n-Ct C-CtC-(CH2)m-R was synthesized. The influence of the length of the alkyl spacer n between the phthalimido group and the diacetylene group, the length of the alkyl spacer m and an additional polar group R on the thermal and UV-induced polymerization was investigated by systematic variation of n, m, and R (for R ) H and m ) 8, n ) 1, 3, 4, 5, 8, 9; for n ) 9 and m ) 3, R ) H, CH2OH, COOH). All synthesized compounds underwent thermal polymerization. The polymerization temperature increased with longer n spacer or shorter m spacer, and no effect was observed on variation of R. For UV-induced polymerization, a spacer length n of more than four carbon atoms was necessary. Introduction of a hydrogen-bond-forming hydroxyl or carboxyl group at the other side of the diacetylene yielded polymers with a significantly higher degree of conjugation and also improved film formation on quartz enormously.

Astrochemistry and Astrobiology: Materials Science in Wonderland?

“…Being essentially out of the scope of this review, mention is given here only to topochemical reactions, which have so far been exploited for polymerization reactions. These include stepwise [2 + 2] photopolymerization of 2,5-styrylpyridine and related diolefins [57,58], thermal or radiation polymerization of diacetylenic derivatives [59,60], and the polymerization of conjugated 1,3-diene monomers, yielding highly stereoregular polymers in the form of polymer crystals [61,62].…”

Topochemical polymerization of unsymmetrical aryldiacetylene supramolecules with nitrophenyl substituents utilizing C–H⋯π interactions

“…In principle, this reaction is usually a photochemical process, though it also occurs thermally. 16 With only minimal packing rearrangements, DA monomers can be polymerized in a topochemical manner, in which single crystals of the monomer can be transformed into polymeric single crystals. The molecular alignment to satisfy topochemical polymerization is at least three-fold (Scheme 1): first, the identity period d of the monomer should be about 4.9 Å.…”

Spectroscopic studies of oligodiacetylenes in solution and polymer film

“…This oligomeric approach has already been successfully utilized to examine a number of p-conjugated materials that include oligothiophenes, 3,12,13 oligoarylenevinylenes 14 and oligotriacetylenes. 15,16 Polydiacetylenes (PDAs) are another class of these versatile materials; [17][18][19][20] a comprehensive review on PDAs has recently been published. 21 Due to their topochemical, solid-state polymerization, PDAs are necessarily highly ordered, with significant p-p-interactions between adjacent PDA chains.…”