Modeling the Crossover between Chemically and Diffusion-Controlled Irreversible Aggregation in a Small-Functionality Gel-Forming System

被引：20

作者：

Corezzi, S. ^{[1
]}

Fioretto, D. ^{[1
]}

De Michele, C. ^{[2
]}

Zaccarelli, E. ^{[2
,3
]}

Sciortino, F. ^{[2
,3
]}

机构：

[1] Univ Perugia, Dipartimento Fis, I-06100 Perugia, Italy

[2] Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy

[3] Univ Roma La Sapienza, CNR, ISC, I-00185 Rome, Italy

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2010年 / 114卷 / 11期

关键词：

KINETICS; THERMODYNAMICS; VISCOSITY; DYNAMICS; POINT;

D O I：

10.1021/jp911165b

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The analysis of realistic numerical simulations of a gel-forming irreversible aggregation process provides information on the role of cluster diffusion in controlling the late stages of the aggregation kinetics. Interestingly, the crossover from chemically controlled to diffusion-controlled aggregation takes place well beyond percolation, after most of the particles have aggregated in the spanning network and only small clusters remain in the sol. The simulation data are scrutinized to gain insight into the origin of this crossover. We show that a single additional time scale (related to the average diffusion time) is sufficient to provide an accurate description of the evolution of the extent of reaction at all times.

引用

页码：3769 / 3775

页数：7