Post-crystallization increases in the mechanical strength of self-assembled fibrillar networks is due to an increase in network supramolecular ordering

作者：Rogers Michael A; Wright Amanda J; Marangoni Alejandro G^*

来源：Journal of Physics D: Applied Physics , 2008, 41(21): 215501.

DOI：10.1088/0022-3727/41/21/215501

Fibre-fibre interactions strongly influence the elastic properties of an organogel and are of critical importance to the ability of the network to entrain liquid oil. At 30 degrees C, there was a significant decrease in the storage modulus in time due to a decrease in the amount of crystalline material (i. e. a decrease in the free induction decay (FID) amplitude) and order of crystalline material ( i. e. an increase in the FID T(2) relaxation time ( i. e. a measure of proton mobility)). Conversely, at 5 degrees C, there was an increase in G' in time but no changes were observed in both the amount of crystalline material and its order. This increase in G' was accompanied by a significant increase in the enthalpy of melt and the melting temperature, which translated to a significant increase in the entropy of melt of the system. This decrease in the absolute entropy of the system in time probably arose due to an increase in the number of van der Waals interactions between 12-hydroxystearic acid fibres. Hence the increased order of the system is due to the fibre-fibre interactions which results in a significant increase in G' in time at 5 degrees C.

• 出版日期2008-11-7