Room Temperature Dynamic Polymers Based on Diels–Alder Chemistry

Abstract

Dynamers based on reversible Diels-Alder chemistry have been obtained and shown to undergo dynamic exchange at room temperature. Their study in solution by small-angle neutron scattering indicated the formation of long and highly flexible chains. Polydispersed molecules gave T(g) values below room temperature, permitting the generation of a dynamic elastomer upon introduction of a dynamic cross-linking agent. The use of a system with a low equilibrium constant gives access to materials with interesting self-healing properties.

Covalent adaptable networks: smart, reconfigurable and responsive network systems

“…6, entry 3). 4,[19][20][21][22] While we have selected the work of Chen et al 5 as the example of DA-based CANs, the discovery and application goes back at least to the 1960s, where the DA reaction was used to crosslink linear polymers. 23 An additional example of the cycloaddition reaction approach, but one that is photoactivated, is the [2+2] photoinduced cycloaddition reaction, commonly involving cinnamate chemistry.…”

Reversible oligomerization of 3-aryl-2-cyanothioacrylamides via [2s + 4s] cycloaddition to substituted 3,4-dihydro-2H-thiopyrans

“…[19] Moreover, Lehn and coworkers investigated highly reversible and dynamic DA systems. [20][21][22] Various dienes and dienophiles were screened regarding their reversibility of the DA reaction. In particular, functionalized fulvenes have been utilized.…”

“…The variation of these functional units resulted in a new generation of highly dynamic polymers. [20,21] Furthermore, the DA reactions between 9,10-dimethylanthracene and cyano-functionalized dienophiles, e.g., dienes as well as tricyanoethynylethylenes, have been investigated. [22] Another interesting reaction is the reversible HDA (i.e.…”

Self‐Healing of Chemical Gels Cross‐Linked by Diarylbibenzofuranone‐Based Trigger‐Free Dynamic Covalent Bonds at Room Temperature

“…[14,19,20] Lehn and co-workers reported new Diels-Alder units that display reversible structural transformation at room temperature in the absence of external stimuli, although no mechanical data on these materials was reported. [21,22] Herein, we present dynamic materials that have the ability to autonomously self-heal under mild conditions such as under air at room temperature, using a novel dynamic covalent bond unit. Diarylbibenzofuranone (DABBF) was employed as a dynamic covalent bond (Scheme 1).…”