Rigid polymer network models

Abstract

Résumé. 2014 Nous présentons un modèle décrivant l'élasticité d'un réseau de chaînes rigides. La variation du module élastique avec la fraction volumique de

Elasticity in Physically Cross-Linked Amyloid Fibril Networks

“…This unexpected finding implies a different mechanism for the percolating amyloid fibril network on addition of sodium chloride, as discussed further below. Figure 2(b) further examines the G 0 dependency on c at fixed I, and an average scaling law G 0 ∼ c 2.2AE0.1 is found, i.e., in good agreement with the theory of cross-linked networks predicting 2.2 for semiflexible polymers [12,13,15] and with other experimental studies such as the cross-linked actin or In this case, G 0 exhibits a slightly stronger dependency on c compared to semiflexible ones and above the exponent of infinitely stiff or pure rod, predicted to be two [16]. Yet, the exponent still falls into the range of the scaling exponents for the cross-linked network, as mentioned above.…”

“…A theoretical framework to describe the elasticity of semiflexible or rigid networks has been developed over the last two decades, primarily to study actin gels [9][10][11][12][13][14][15]. These approaches have been particularly successful to describe the dependency of elasticity on polymer concentration, chain flexibility [15,16], cross-linking procedure [12][13][14], and cross-linking density [15]. Other factors, such as the connectivity architectures [11], the affinity and size of cross-linker [10], and the deformation nature (affine or nonaffine) [9], have also been studied.…”

Preparation and characterization of polyacrylic acid‐poly(vinyl alcohol)‐based interpenetrating hydrogels

“…In Figure 2(a), the evolution of the storage modulus with temperature for PAAc gels of different degrees of crosslinking is depicted. Two conclusions can be drawn from Figure 2(a): (1) the storage modulus increases linearly with temperature, a behavior characteristic of chemical gels whose elasticity is of entropic origin; 20 and (2) the storage modulus increases with the degree of crosslinking of the gels. Figure 2(b) shows the variation of the equilibrium modulus with the degree of crosslinking for PAAc hydrogels in swelling equilibrium.…”

Two-step build-up of a thermoreversible polymer network: From early local to late collective dynamics

“…A purely physical gel and a chemical one exhibit distinct network topologies, since triple-helix CL are spatially extended, involving three chains, while the pointlike covalent ones connect two chains only. However, as gel elasticity is of purely entropic origin, G is controlled by the entropy reduction of the polymer chain system due to crosslinking, hence is an indicator of the density of degrees of freedom which are frozen at the corresponding stage of gelation [14]. So, our procedure amounts to choosing for the common reference the situation where the density of degrees of freedom which remain available for further evolution for both gels is comparable.…”