On the Size Effect of Gelation Kinetics in RF Aerogels

Gels

Lorenz Ratke¹  Anna Hajduk²  Francoise Quignard² 

[1]Institute of Materials Research, German Aerospace Center, DLR, 51170 Köln, Germany

[2] E-Mail

关键词: gelation;    aerogels;    shear flow;    aggregation kinetics;    size effect;   

DOI  :  10.3390/gels1020276

来源: mdpi

【 摘 要 】

We experimentally and theoretically investigate the size effect of gelation using Resorcinol-Formaldehyde aerogels. We find a clear dependence of gelation time on the sample size under mild shear conditions. We developed a theoretical model based on Smoluchowski’s aggregation model adding, however, a growth term which accounts for the continuous growth of the colloidal particles while clustering happens. The model is solved analytically and agrees with our experimental observations for base catalyzed RF-gels.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.