Coupling between criticality and gelation in "sticky" spheres: A structural analysis

非粘性颗粒的胶体凝胶化

Colloidal Gelation with Non-Sticky Particles

本研究通过数值模拟探究含非粘性颗粒的二元胶体复合材料的凝胶化，发现非粘性颗粒以有效体积分数限制凝胶化并引入竞争长度尺度，且该机制在多种凝胶模型中具有普遍性。

Anisotropic viscoelastic phase separation in polydisperse hard rods: non-sticky gelation

Spinodal demixing of systems into two phases having very different viscosities leads to viscoelastic networks, i.e. gels. Here we consider demixing in a colloidal system where one phase is a nematic liquid crystal with a strongly anisotropic viscosity. We combine real space analysis of a sepiolite clay system with molecular dynamics computer simulation. We find a long-lived network with many of the characteristics of a colloidal gel. Remarkably the anisotropic viscosity means that flow is possible within the nematic network, but only along the network, which thus preserves its structure, leadi…

The nature of the glass and gel transitions in sticky spheres

Glasses and gels are the two dynamically arrested, disordered states of matter. Despite their importance, their similarities and differences remain elusive, especially at high density. We identify dynamical and structural signatures which distinguish the gel and glass transitions in a colloidal model system of hard and "sticky" spheres. Gelation is induced by crossing the gas-liquid phase-separation line and the resulting rapid densification of the colloid-rich phase leads to a sharp change in dynamics and local structure. Thus, we find that gelation is first-order-like and can occur at much h…

胶体系统中黏性圆柱体凝胶形成的计算机模拟

Computer Simulation of Gel Formation in Colloidal Systems of Sticky Rods

本研究开发了用于模拟黏性圆柱体胶体凝胶形成的计算框架，通过拓扑数据分析方法分析了凝胶结构，并与实验数据进行比较，展示了方法的潜力。

Universal scaling and characterisation of gelation in associative polymer solutions

A Brownian dynamics algorithm is used to describe the static behaviour of associative polymer solutions. Predictions for the fractions of stickers bound by intra-chain and inter-chain association, as a function of system parameters, such as the number of stickers, the number of monomers between stickers, the solvent quality, and concentration are obtained. A systematic comparison with the scaling relations predicted by the mean-field theory of Dobrynin (Macromolecules, 37, 3881, 2004) is carried out. Different regimes of scaling behaviour are identified depending on the monomer concentration, …

A minimal coarse-grained model to study the gelation of multi-armed DNA nanostars

DNA is an astonishing material that can be used as a molecular building block to construct periodic arrays and devices with nanoscale accuracy and precision. Here, we present simple bead-spring model of DNA nanostars having three, four and five arms and study their self-assembly using molecular dynamics simulations. Our simulations show that the DNA nanostars form thermodynamically stable fully bonded gel phase from an unstructured liquid phase with the lowering of temperature. We characterize the phase transition by calculating several structural features such as radial distribution function …