Gelation flow-induced

Flow imparts both extension and rotation to fluid elements. Thus, polymer molecules will be oriented and stretched under these circumstances and this may result in flow-induced phenomena observed in polymer systems which include phase-changes, crystallization, gelation or fiber formation. More generally, the Gibbs free energy of polymer blends or solutions depends under non-equilibrium conditions not only on temperature, pressure and concentration but also on the conformation of the macromolecules (as an internal variable) and hence, it is sensitive to external forces. 

Cates M, Turner M (1990) Flow-induced gelation of rodlike micelles. Europhys Lett 7 ... 

Bruinsma R, Gelbart W, Ben-Shaul A (1992) Flow-induced gelation of living (micellar) polymers. J Chem Phys 96 7710-7727... 

Shlrasakl Y, Tanaka J, Makazu H, Tashlro K, Shoji S, Tsukita S, Funatsu T (2006) On-chip cell sorting system using laser-induced heating of a thermoreversible gelation polymer to control flow. Anal Chem 78(3) 695-701... 

Another rheological application is in conformance control whereby the water flow is diverted due to fatty amine oxide induced gelation. This plugging of... 

The frequency-dependent increase in storage modulus to 1 GPa and the frequency-dependent loss peaks signify vitrification during cure. Vitrification, as expected, is frequency-dependent since it is the cure-induced glass transition. Gelation, however, is an event that is independent of frequency. It is important to note that the shear sandwich experiment is useful primarily for B-staged resins whose viscosity is sufficient so that the resin does not flow out of the gap between the parallel-plate shear sandwich fixtures. 

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