Topochemical Reactions of Monomers with Conjugated Triple‐Bonds VII Mechanism of Transition from Monomer to Polymer Phase During Solid‐State Polymerisation

Kaiser, J.; Wegner, Gerhard; Fischer, Erhard W.

doi:10.1002/ijch.197200022

Cited by 122 publications

(22 citation statements)

References 25 publications

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“…Poly diacetylene. Solid state synthesis (Kaiser et al 1972, Baughman 1974) has recently been used to obtain polydiacetylenes of a high degree of structural per fection. This in turn has led to the measurement of a number of physical properties of this polymer (Stevens et al 1978) and several theoretical studies (Parry 1976, Boudreaux 1975, Cojan et al 1977, Wilson 1975, Philpott 1977 as well.…”

Section: Conjugated One and Two Dimensional Polymersmentioning

confidence: 99%

Conjugated one and two dimensional polymers

1979

Proc. R. Soc. Lond. A

396

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The band structures of some existing and hypothetical one and two dimensional conjugated polymers are examined in this work. The aim is to explore how the band gap sizes and the occurrence of partially filled bands are related to unit cell constitution and the geometrical disposition of the atoms in the unit cell. Among the polymers explored are poly-acetylene, polydiacetylene, polyphenylene, polyacene, graphite, boron nitride, polynitrile, polycyanonitrile, polypyridinopyridine, paracyanogen, the C 3 N net, (SN) x , (XCNSN) x , and C 2 S 3 N 6 net.

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Section: Conjugated One and Two Dimensional Polymersmentioning

confidence: 99%

Conjugated one and two dimensional polymers

1979

Proc. R. Soc. Lond. A

396

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“…16,97 However, a few exceptions are known for which it is observed that polymerization generates a polymer that is amorphous to X-rays after extraction of the remaining monomer: such a situation was encountered during the polymerization of 2,4-hexadiyne-1,6-diol 15 and during that of modification I of 2,4-hexadiyne-1,6-diol bis(phenylurethane). 26 Thus, it is possible that amorphization of poly-4 originates from the removal of the unreacted monomer. On the other hand, this observation is a clear indication that solid-state polymerization of 4 proceeds in a homogeneous manner.…”

Section: Solid-state Stability Ofmentioning

confidence: 99%

“…8,9 In case these interactions are ineffective at organizing suitably DA molecules in the crystal lattice, one way of solving the problem is to look for other polymorphs. 16,26 This solution is simple to implement, yet it does not always work and is hardly predictable. Alternatively, it is possible to use tools from the crystal engineer arsenal, especially cocrystals.…”

Section: Introductionmentioning

confidence: 99%

Stability and solid-state polymerization reactivity of imidazolyl- and benzimidazolyl-substituted diacetylenes: pivotal role of lattice water

et al. 2013

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International audience1,6-Bis(1-imidazolyl)-2,4-hexadiyne (1) and1,6-bis(1-benzimidazolyl)-2,4-hexadiyne (5) have beenpreparedby a novel method that consists in refluxing excess imidazole and benzimidazole with 2,4-hexadiyne-1,6-diol bis(p-toluenesulfonate),pTS (3). This procedure is a viable alternative to the widely used Hay coupling protocol in case the target diyne possesses substituents capable of deactivating the copper catalyst by complexation. Diyne1crystallizes as a hydrate,1?H2O(2). For this compound, water is essential toachieve a crystalline material, and attempts to obtain crystals without included solvent were unsuccessful. In the structure of2, the organic fragments organize around the water molecule and interact with it through a dense network of hydrogen bonds. The CMC-CMC moieties are not oriented suitably for topochemical polymerization, and when trying to alter the organizationof the crystal by heating so as to induce polymerization, water is lost in an abrupt fashion that leads to instantaneous decomposition into polyaromatic-like species. Similar results were observed when water was removedin vacuo at room temperature. The benzimidazole-containing compound can be crystallized with water molecules (4)orwithout(5). X-ray crystallography shows that the structure of 5is organized by numerous C-H...N, C-H...p,andimidazolyl...imidazolyl p-p interactions. The diacetylene molecules almost have the right arrangement for topochemical polymerization, withpossibly reactingCMC-CMC fragments not beingparallel, a rare situation indiacetylene chemistry. Yet, experiments showthat topochemical polymerizationdoes not occur. Incorporationofwater in the lattice of5leads toa solvate that is topochemically reactive. Unlike2, however, water molecules in 4are not isolated but are organized as ribbons. Spectroscopic characterization of the polymer of4indicates that it is a blue phase polymer, with water coordinated to it. This study shows that it is possible to use water, and more generally solvent molecules, to transform a nonreactive diacetylene into a reactive one, even though this approach is less predictable than the cocrystal approach developed by Fowler, Lauher, and Goroff. The solvate approach is simple to implement, quite versatile because of the large rangeof solvents available, andonedoes not face theproblemof having to remove the host in case one needs to recover the polymer. Previous studies describing a similar approach are scarce

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“…Most of them are polymorphic with different activities. Wegner (1969) and Kaiser et al, (1972) described three distinct forms for the 2,4 Aexadiyne 1,6 bis-(phenylurethane) (referred to as HDPU); this author has determined the lattice parameters of the form II, moderately reactive; we have recently indexed the powder data and we are beginning to resolve the structure of this HDPU form. The 2,4 Aexadiyne-1,6 bis-(/w-/olylurethane).…”

Section: Introductionmentioning

confidence: 99%