Film‐forming behavior and mechanical properties of colloidal silica/polymer latex blends with high silica load

Abstract

In this article, silica sol (diameter: 8–100 nm) and polymer latex (Tg < 25°C) were mixed and dried at room temperature to prepare nanocomposite films with high silica load (≥50 wt %). Effects of silica size, silica load, and the Tg of the polymer on the film‐forming behavior of the silica/polymer latex blend were investigated. The transparency, morphology, and mechanical properties of the nanocomposite films were examined by UV–Vis spectroscopy, SEM, and nanoindentation tests, respectively. Transparent and crack‐free films were produced with silica loads as high as 70 wt %. Thirty nanometers was found to be the critical silica size for the evolution of film‐forming behavior, surface morphology, and mechanical properties. Colloidal silica particles smaller than this critical size act as binders to form strong silica skeleton. This gives the final silica/polymer nanocomposite film its porous surface and high mechanical strength. However, silica particles with sizes of 30 nm or larger tend to work as nanofillers rather than binders, causing poor mechanical strength. We also determined the critical silica load appeared for the mechanical strength of silica/polymer film at high silica load. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Evaporation-driven self-assembly of binary and ternary colloidal polymer nanocomposites for abrasion resistant applications

“…It has been shown that silica-containing composites exhibit an increased elastic modulus 30 , yield stress 31 , hardness, and scratch resistance 32 . Conventional sol-gel methods for producing polymer/silica composites involve the use of tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS), both of which are relatively expensive and can result in the release of volatile organic solvents (VOCs) 33 . A simple and greener alternative is the drying of latex blends containing colloidal silica.…”

“…A simple and greener alternative is the drying of latex blends containing colloidal silica. Several publications focus on the creation of latex/silica nanocomposite films by drying latex dispersions containing silica 22,[33][34][35][36] . Martinez and Lewis, and Yang et al studied the film forming behaviour and mechanical properties of latex films containing colloidal silica particles 33,35 .…”

“…Several publications focus on the creation of latex/silica nanocomposite films by drying latex dispersions containing silica 22,[33][34][35][36] . Martinez and Lewis, and Yang et al studied the film forming behaviour and mechanical properties of latex films containing colloidal silica particles 33,35 . Meanwhile, Grillet et al and Kobayashi et al investigated the influence of silica on film morphology and polymer interdiffusion 22,34 .…”

The effect of octamethylcyclotetrasiloxane (D4) addition on the structure and properties of film‐forming polyacrylate/silica core–shell composite particles

“…The abrasion resistance performance was improved slightly for the polyacrylate/silica nanocomposite films with D 4 , which resulted from the outstanding wear and durability of silicon. However, the improvement was limited because polyacrylate/silica nanocomposite without D 4 already showed excellent abrasion resistance performance (mass loss 0.024 g) compared to the literature . There was not much potential to improve for the abrasion resistance performance even if D 4 was added to the system.…”

“…However, the improvement was limited because polyacrylate/ silica nanocomposite without D 4 already showed excellent abrasion resistance performance (mass loss 0.024 g) compared to the literature. 25,29 There was not much potential to improve for the abrasion resistance performance even if D 4 was added to the system. And the results confirmed the assumption.…”