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Colloidal gelation induced by ring polymers
DOI:10.1103/PhysRevResearch.6.013079.png)
摘要
En 中文
We provide unambiguous experimental evidence that ring polymers are stronger depleting agents in colloidal suspensions than their linear counterparts. We use an intermediate volume fraction (phi c = 0.44) colloidal gel based on the classic poly(methyl methacrylate) (PMMA) hard spheres, in which the polystyrene depletant is either linear or ring of the same molar mass or the same size. We systematically increase the depletant concentration from zero (no attraction) to well above the gelation point and find that in the presence of rings, gels are formed at smaller concentrations and possess a larger storage modulus in comparison to those induced by the linear chains. Consequently, the yield stress is enhanced; however, the yield strain (gel deformability) remains concomitantly unaffected. Our experimental findings are in agreement with theoretical calculations based on effective interaction potentials. Hence, polymer architecture is a powerful entropic tool to tailor the strength of colloidal gels.
Keyword:
CYCLIC POLYSTYRENE
STAR POLYMERS
FLUID
POTENTIALS
TRANSITION
VISCOSITY
BEHAVIOR
GELS
期刊
IF:
4.2
论文数:
7.6K
被引数:
2.7W
机构
引用论文
Nonlinear Architectures Can Alter the Dynamics of Polymer-Nanoparticle Composites
MACROMOLECULES
IF5.2

