ABSTRACT
Dynamic bonds can facilitate reversible formation and dissociation of connections in response to external stimuli, endowing materials with shape memory and self-healing capabilities. Temperature is an external stimulus that can be easily controlled through heat. Dynamic covalent bonds in response to temperature can reversibly connect, exchange, and convert chains in the polymer. In this review, we introduce dynamic covalent bonds that operate without catalysts in various temperature ranges. The basic bonding mechanism and the kinetics are examined to understand dynamic covalent chemistry reversibly performed by equilibrium control. Furthermore, a recent synthesis method that implements dynamic covalent coupling based on various polymers is introduced. Dynamic covalent bonds that operate depending on temperature can be applied and expand the use of polymers, providing predictions for the development of future smart materials.
ABSTRACT
Nanofibers have gained much attention because of the large surface area they can provide. Thus, many fabrication methods that produce nanofiber materials have been proposed. Electrospinning is a spinning technique that can use an electric field to continuously and uniformly generate polymer and composite nanofibers. The structure of the electrospinning system can be modified, thus making changes to the structure, and also the alignment of nanofibers. Moreover, the nanofibers can also be treated, modifying the nanofiber structure. This paper thoroughly reviews the efforts to change the configuration of the electrospinning system and the effects of these configurations on the nanofibers. Excellent works in different fields of application that use electrospun nanofibers are also introduced. The studied materials functioned effectively in their application, thereby proving the potential for the future development of electrospinning nanofiber materials.