Segregated Networks of Carbon Black in Poly(vinyl acetate) Latex: Influence of Clay on the Electrical and Mechanical Behavior

Abstract

Films were prepared from mixtures of PVAc latex, CB, and natural sodium montmorillonite clay. In the absence of clay, these composites exhibit a percolation threshold of 1.2 vol.‐% CB, which is nearly an order of magnitude lower than that observed for composites prepared using PVAc solution. SEM images reveal a segregated CB network that is the result of excluded volume created by the much larger polymer particles in the latex. With the addition of 0.2 wt.‐% clay, the percolation threshold is reduced to 0.9 vol.‐% carbon black due to clay‐induced networking. The storage modulus is also enhanced by the presence of clay, although higher clay concentration appears to adversely affect electrical and mechanical behavior of these composites.

Electrical and thermomechanical properties of segregated nanocomposites based on PVC and multiwalled carbon nanotubes

“…Considerably lower value of u c comparatively with usual filled polymers can be attained due to this effect [12][13][14][15][16][17][18]. Such an ordered distribution of filler is realized, for example, in polymer blends when the filler is localized in one polymer phase or on the interface [19,20] and in the latex-based composites [21,22]. The compacting method (pressing of mechanical mixture of the polymer and filler powders) under conditions that the size of polymer particles D greatly exceeds the size of filler particles d, D ) d, is one of simple and effective methods to form the segregated systems [12][13][14][15][16][17][18]23].…”

Carbon Nanotubes as Conductive Filler in Segregated Polymer Composites - Electrical Properties

“…The polymer/carbon black composites were thoroughly studied as well (Chan et al, 1997;Chiteme & Mclachlan, 2000;Yacubowicz et al, 1990a;Youngs, 2003;Zhang et al, 2005). Segregated structure of conductive filler was also obtained in emulsions where the particles of conductive filler surround the particles of emulsified polymer (Bridge et al, 1990;Grunlan et al, 2001;Kim et al, 2008;Miriyala et al, 2008). The values of percolation threshold in poly(vinyl acetate)/carbon black composites prepared with using a solution (random distribution of filler) or an emulsion (latex) were 8.18 and 1.2 %, respectively (Miriyala et al, 2008).…”

“…Segregated structure of conductive filler was also obtained in emulsions where the particles of conductive filler surround the particles of emulsified polymer (Bridge et al, 1990;Grunlan et al, 2001;Kim et al, 2008;Miriyala et al, 2008). The values of percolation threshold in poly(vinyl acetate)/carbon black composites prepared with using a solution (random distribution of filler) or an emulsion (latex) were 8.18 and 1.2 %, respectively (Miriyala et al, 2008). A variety of models have been proposed to describe the electrical properties of segregated polymer systems.…”

Electrophysical and Thermomechanical Properties of the Segregated Polymeric Systems Containing Carbon Fillers

“…Переход «диэлектрик-проводник» в полимерах осуществляется за счёт введения в них электропроводящих наполнителей. Для получения широкого диапазона электропроводности используются наполнители с металлическими или карбоновыми частицами разной формы и дисперсности [4][5][6][7][8]. Часто в роли проводящего наполнителя выступают микро/наночастицы карбона, такие как сажа, графен, терморасширенный графит и т.д.…”