Butatriene-Based Polymer Chemistry. 2. Synthesis and Characterization of Poly[1,1,4,4-bis(pentamethylene)-1,2,3-butatriene]^,1

Abstract

The cumulene 1,1,4,4-bis(pentamethylene)butatriene has been shown to undergo a thermally induced 1,4 free-radical polymerization to yield a crystalline polymer with a unique nonconjugated acetylene containing backbone. This polymerization occurs in both the melt and in solution. Typical free-radical inhibitors prevent the thermally induced polymerization. The reaction occurs in the presence or absence of free-radical initiators. The polymer is crystalline with a triclinic unit cell (a ) 9.87 Å, b ) 6.10 Å, c ) 4.97 Å, R ) 113.7°, ) 85.2°, γ ) 100.6°). No melting or glass transition is observed via differential calorimetry, but an irreversible exothermic transition is observed from both solution and melt polymerized material. This is interpreted as a cold crystallization process. Trapping of the polymerizing monomer with TEMPO leads to soluble oligomers. † This paper is dedicated to Professor Shelton Bank on the occasion of his 65th birthday.

Butatriene-Based Polymer Chemistry. 3. New Route to Substituted Poly(acetylene)s through the Base-Catalyzed Rearrangement of Poly(2-butyne-1,4-diyl)s

“…Unlike the previously studied 1,4-bis(pentamethylene)-1,2,3-butatriene, , 1,1,4,4-tetramethyl-1,2,3-butatriene, and the parent butatriene, this material is stable in the liquid phase and can be purified by conventional means. When dissolved in THF, degassed, and heated at 120 °C for 48 h, a soluble lightly yellow polymer is produced.…”

“…The polymerization of simple butatrienes has long frustrated spectroscopists in their attempts to isolate and study the free monomeric molecule. − Carothers observed this phenomenon and obtained a patent on the potential use of butatriene as a reactive monomer, not understanding the nature of the polymer formed . Recently, we have been studying the structure and potential applications of butatrienes as monomers in addition polymerization. − In reviewing of the literature concerning 1,2,3-butatriene, there were reports that in some situations, the normally white solid formed from its polymerization would convert to a yellow, blue or even black material . This intrigued us as it implied the formation of a conjugated system.…”

“…8 Recently, we have been studying the structure and potential applications of butatrienes as monomers in addition polymerization. [9][10][11] In reviewing of the literature concerning 1,2,3-butatriene, there were reports that in some situations, the normally white solid formed from its polymerization would convert to a yellow, blue or even black material. 2 This intrigued us as it implied the formation of a conjugated system.…”

The synthesis of new thiosubstituted butadienes, butenynes and butatrienes

“…Unlike alkanes and most alkenes, cumulenes tends to be rigid, which makes them appealing for molecular nanotechnology. [10][11][12] Thiosubstituted compounds are used as electronic conductors, ferromagnets, electron-accepting supramolecules, optical materials in material chemistry and as stabilizers in polimer chemistry.…”

Singlet−Triplet Gap in 1,2,3-Butatriene and Its Consequences on the Mechanism of Its Spontaneous Polymerization

“…This system was also inhibited by the presence of hindered phenols but required no initiator for polymerization to occur. As part of our ongoing interest in the polymer chemistry of butatrienes, 7 we have undertaken a study to understand the mechanism and energetics of this reaction as a means of predicting what structural features would allow for better control of the chemistry. The current study reports on molecular orbital theory based analysis of the reaction chemistry of the parent compound.…”