A Comparison Between the Densification Kinetics of Colloidal and Polymeric Silica Gels

1984 ◽  
Vol 32 ◽  
Author(s):  
C. J. Brinker ◽  
W. D. Drotning ◽  
G. W. Scherer
Keyword(s):  
Structural Relaxation ◽  
Colloidal Particles ◽  
Polymer Gels ◽  
Branched Polymers ◽  
Silica Gels ◽  
Polymeric Gels ◽  
Colloidal Gel ◽  
Constant Viscosity ◽  
Kinetics Of ◽  
Isothermal Viscosity

ABSTRACTSilica gels were prepared by three methods in which the original silicate species varied from extended linear or randomly branched polymers to more highly crosslinked clusters to colloidal particles of anhydrous silica. During isothermal sintering experiments, the viscosities of the two polymer gels increased significantly (up to 3 orders of magnitude) while the isothermal viscosity of the colloidal gel was constant. Viscosity increases were explained by crosslinking and structural relaxation of the polymeric gels.

INHOMOGENEOUS LARGE DEFORMATION KINETICS OF POLYMERIC GELS

2013 ◽  
Vol 05 (01) ◽  
pp. 1350001 ◽  
Author(s):  
WILLIAM TOH ◽  
ZISHUN LIU ◽  
TENG YONG NG ◽  
WEI HONG
Keyword(s):  
Large Deformation ◽  
Soft Matter ◽  
Inner Core ◽  
Kinetic Studies ◽  
Fe Model ◽  
One Dimensional ◽  
Simplified Approach ◽  
Deformation Kinetics ◽  
Polymeric Gels ◽  
Kinetics Of

This work examines the dynamics of nonlinear large deformation of polymeric gels, and the kinetics of gel deformation is carried out through the coupling of existing hyperelastic theory for gels with kinetic laws for diffusion of small molecules. As finite element (FE) models for the transient swelling process is not available in commercial FE software, we develop a customized FE model/methodology which can be used to simulate the transient swelling process of hydrogels. The method is based on the similarity between diffusion and heat transfer laws by determining the equivalent thermal properties for gel kinetics. Several numerical examples are investigated to explore the capabilities of the present FE model, namely: a cube to study free swelling; one-dimensional constrained swelling; a rectangular block fixed to a rigid substrate to study swelling under external constraints; and a thin annulus fixed at the inner core to study buckling phenomena. The simulation results for the constrained block and one-dimensional constrained swelling are compared with available experimental data, and these comparisons show a good degree of similarity. In addition to this work providing a valuable tool to researchers for the study of gel kinetic deformation in the various applications of soft matter, we also hope to inspire works to adopt this simplified approach, in particular to kinetic studies of diffusion-driven mechanisms.

Study on vulcanization kinetics of constant viscosity natural rubber by using a rheometer MDR2000

2013 ◽  
Vol 130 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Zhang Bei-Long ◽  
Wang Yong-Zhou ◽  
Wang Ping-Yue ◽  
Huang Hong-Hai
Keyword(s):  
Natural Rubber ◽  
Vulcanization Kinetics ◽  
Constant Viscosity ◽  
Kinetics Of
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