Adhesion and Stress Relaxation of Coalesced Latex Blends
Abstract
The mechanical and adhesive properties of coalesced latex blends are of interest due to their applicability in several areas, including commercial adhesives and latex paints. We have tested the mechanical and adhesive behaviors of latex coatings formed by coalescence in water. The coatings are composed of two latex systems, a softer system with a particle size of 57nm, and a harder system with a particle size of 268nm. By varying the proportion of soft particles (Tg = -30 C) to hard particles (Tg = 20 C) in dispersions, we are able to show a relationship between the volume fraction of the hard latices and the effective work of adhesion. This behavior can be studied through use of an extension of the JKR method for adhesive testing. In the JKR method, a rigid hemispherical indenter is brought into contact with the coating, and we measure the resultant adhesion . We have also obtained relaxation data for the latex blends by fitting experimental data to multi-element Maxwell model. We find that very low volume fractions of the soft particles significantly influence stress relaxation, but that larger volume fractions are required to noticeably affect the adhesive behavior.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2000
- Bibcode:
- 2000APS..MARL36158F