Water-Assisted Production of Thermoplastic Nanocomposites: A Review

Abstract

Water-assisted, or more generally liquid-mediated, melt compounding of nanocomposites is basically a combination of solution-assisted and traditional melt mixing methods. It is an emerging technique to overcome several disadvantages of the above two. Water or aqueous liquids with additives, do not work merely as temporary carrier materials of suitable nanofillers. During batchwise and continuous compounding, these liquids are fully or partly evaporated. In the latter case, the residual liquid is working as a plasticizer. This processing technique contributes to a better dispersion of the nanofillers and affects markedly the morphology and properties of the resulting nanocomposites. A survey is given below on the present praxis and possible future developments of water-assisted melt mixing techniques for the production of thermoplastic nanocomposites.

Polymer/boehmite nanocomposites: A review

“…Some BA producers even publish the size dispersion characteristics of BA in aqueous (slightly acidified) solutions. This fact triggered the development of water‐assisted (WA) (mediated) incorporation of BA in polymers . Figure (a) also suggests that surface hydroxyl groups may work as “anchoring” sites for surface modification.…”

“…BA is incorporated into thermoplastics mostly by conventional melt compounding in batch (internal mixer) or continuous operations (extruder). WA melt compounding, exploiting the dispersibility of BA in water, was pioneered by Karger‐Kocsis et al . The “polymerization filling” technique making use of a BA‐supported catalyst in the polymerization of olefins, was suggested by the group of Mülhaupt A BA‐supported catalyst was already tried for olefin polymerization in 2002 .…”

“…The “polymerization filling” technique making use of a BA‐supported catalyst in the polymerization of olefins, was suggested by the group of Mülhaupt A BA‐supported catalyst was already tried for olefin polymerization in 2002 . A further advantage of WA melt compounding is that the nanocomposite preparation may be associated with inline impact modification of the corresponding polymer . Rubber latex may be used for this purpose.…”

Flame retarded poly(lactic acid): A review

“…Stoclet et al [51] produced PLA nanocomposites based on halloysite nanotube (HNT), using waterassisted extrusion. Water-assisted melt compounding of suitable nanofillers is a straightforward and safe method of producing nanocomposites [58]. The effect of HNT on the dispersion and fire properties of the water-assisted extruded nanocomposites (PLA-H-W) were evaluated and compared with those of traditional melt extruded nanocomposites (PLA-H).…”

Preparation and Properties of Thermoplastic Starch/Bentonite Nanocomposites

“…To date there are numerous techniques to achieve an appropriate dispersion and an exfoliated state of nanoparticles, such as in situ polymerization, solvent-assisted techniques and melt compounding. Another efficient way could be the introduction of nano-additives in their aqueous dispersions during melt mixing of suitable polymers [9]. Disadvantage of this method is that most polymers are prone to hydrothermal decomposition.…”