Diacetylene crosslinking groups

During the late 1960s, Wegner reported that single-crystalline diacetylenes could be topochemically polymerized to ene-yne polydiacetylenes [78], and several groups subsequently applied this chemistry to crosslinking polymerizations in 2-D confinement. For example, Leblanc synthesized the dendrimer-based amphiphile 34 in which sixteen 10,12-pentacosadiynoic acid chains were coimected to the periphery of a third-generation poly(amidoamine) (PAMAM) dendrimer [79]. A monolayer of this dendritic amphiphile was prepared at the air/water interface, in which the... 

Carboranylenesiloxane Polymers Containing Thermally Crosslinkable or Vulcanizable Diacetylene Groups... 

In another paper, Wang et ai, also reported preparation of polymers containing pendant propargyl groups that can also be effectively crosslink upon UV irradiation in the presence of a small amounts of W(CO)6. The polymer, like the ones above, crosslinking is a result of conversion of the acetylenic units to polyene and diacetylene moieties in the crosslinked system. 

Nallicheri examined the influence of hard domain cohesion on the hysteresis behaviour. The hard domains of these materials were selectively crosslinked in the solid state by polymerizing the diacetylene groups contained within their HS. For materials with weakly associated HS, it oberved that low levels of crosslinking... 

The reaction chemistry of the diacetylene groups in the crosslinkable polyimide blends needs to be examined in order to understand how these materials can be crosslinked without reducing gas permeability. This report presents the initial results toward this goal. Differential scanning calorimetry and solid-state NMR data are presented for the reactive diacetylene-containing homopolymer. Before these data are described, permeability data on the crosslinkable polyimide blends are presented that expand upon our previously published work on these materials. 

Energetic pol5nners are useful in rocket propellant binder compositions, as well as in propellant compositions for air bags in the automotive industry. They are, and formed from, poly(ether)s bearing pendant azide groups crosslinked without a catalyst by a diacetylene compound (42), or triazole and tetrazole pol5nners, respectively. 

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