Producing Supramolecular Functional Materials Based on Fiber Network Reconstruction

Abstract

Here, the creation of new supramolecular functional materials based on the reconstruction of three‐dimensional interconnecting self‐organized nanofiber networks by a surfactant is reported. The system under investigation is N‐lauroyl‐L‐glutamic acid di‐n‐butylamide in propylene glycol. The architecture of networks is implemented in terms of surfactants, e.g. sorbitan monolaurate. The elastic performance of the soft functional material is either weakened or strengthened (up to 300% for the current system) by reconstructing the topology of a fiber network. A topology transition of gel fiber network from spherulite‐like to comb‐like to spherulite‐like is performed with the introduction of this surfactant. The Span 20 molecules are selectively adsorbed on the side surfaces of the crystalline fibers and promote the nucleation of side branches, giving rise to the transformation of the network architecture from spherulite‐like topology to comb‐like topology. At high surfactant concentrations, the occurrence of micelles may provide an increasing number of nucleation centers for spherulitic growth, leading to the reformation of spherulite‐like topology. An analysis on fiber network topology supports and verifies a perfect agreement between the topological behavior and the rheological behavior of the functional materials. The approach identified in this study opens up a completely new avenue in designing and producing self‐supporting supramolecular functional materials with designated macroscopic properties.

Insights into localized manipulation of organogel-related microcrystalline spherulite formation

“…This mechanism complements the molecular view of self-assembly, allowing a more resolved overall model for the processes of gel formation [11,13,18,22,27]. The basic constitution of organogel networks can be classified as multi-domain or single domain [13,15,18,20,22,24,27,30].…”

“…The primary nucleation rate [12][13][14][15]18,22,24,27] and the growth of the fibers, including the degree of branching [8,13,14,17,18,21,22,24,27,28], have been determined to be influential on the resulting network structure. Based on these aspects, engineering the fiber networks in already known organogel systems through chemical or physical means has been emerging as a strong alternative to screening M a n u s c r i p t 2 for new gelators through synthesis [8,10,11,[13][14][15]17,18,[20][21][22]24,25,27,30]. Successful examples of the engineering have been realized through temperature control [7][8][9]11,13,14,16,18,[22][23][24], chemical additives [8,11,…”

“…The multi-domain networks are based on spherulites, structural subunits [11][12][13][14][15][18][19][20]22,24,27,28,30,31] formed by Cayley-tree-like [17,21] fiber-growth progressing radially from a central point of origin. Mutually exclusive spherulites with distinct boundaries are formed in cases where the fibers from individual spherulites do not interpenetrate each other [13,15,20,22,27], forming a multi-domain system.…”

“…Being controlled by the formation processes, the overall fiber network structure is known to determine the macroscopic properties of the gels or gelatinous materials [8,11,13,14,[18][19][20]22,24,25,[27][28][29]. The primary nucleation rate [12][13][14][15]18,22,24,27] and the growth of the fibers, including the degree of branching [8,13,14,17,18,21,22,24,27,28], have been determined to be influential on the resulting network structure.…”

“…Based on these aspects, engineering the fiber networks in already known organogel systems through chemical or physical means has been emerging as a strong alternative to screening M a n u s c r i p t 2 for new gelators through synthesis [8,10,11,[13][14][15]17,18,[20][21][22]24,25,27,30]. Successful examples of the engineering have been realized through temperature control [7][8][9]11,13,14,16,18,[22][23][24], chemical additives [8,11,[13][14][15], ultrasound [27,30], self-seeding of fibers [24], and volume confinement [20,25], either separately or in a combination. The temperature profile of the organogel system may affect the network formation via cooling rate [7,9,16,23] and changes in the state of saturation [7][8][9]11,13,1...…”