Page 112 - Polymer-based Nanocomposites for Energy and Environmental Applications

88 Polymer-based Nanocomposites for Energy and Environmental Applications

Lid

Neoprene cables

Sensors attachment

Fig. 3.8 Photo of sensor arrangement inside pilot test cells [58].

variation, with the purpose of the assessment of the effect of PCM incorporation. The
test results indicated that the difference in the maximum internal temperature between
the two test cells was 2.6°C for the spring day while this difference was 2°C for the
summer day. The numerical modeling of the experiment was also done, and the results
were quite closely.
The incorporation of PCMs into various building applications necessitates a devel-
opment of a novel route for preparing PCM composite in that offer an improved ther-
mal conductivities of PCMs using an easier and lower cost of processing. As
mentioned previously, the form-stable PCMs generally consist of phase-change mate-
rials and supporting materials such as cement, lime, mineral fillers, clays, and chem-
ical additives [59]. The supporting materials not only provide a good mechanical
strength to the PCM blend but also prevent the leakage of solid-liquid PCM during
phase-change process. So, among the nanoclay, supporting materials have a high
surface-to-volume ratio in the micrometer to nanometer range length scale [60].
Furthermore, they are well-known that their blends with PCM have many attractive
properties such as a higher energy storage density and a higher thermal conductivity,
being nonflammable, being inexpensive, and being readily available. To understand
the effect of nanoclays on PCM properties, it is important to highlight the clay struc-
ture and their chemical modification types.

3.5 Nanoclay

3.5.1 Structures and types of nanoclay

Nanoclays used as additives in many applications for numerous desired effects are
receiving a higher interest [61]. In general consideration, this term “nanoclay” is
applied to the natural material having a plastic property and a very fine size generally
smaller than 100 nm [62]. They are largely divided into two categories mainly
described by the arrangement of tetrahedral and octahedral sheets in the layered struc-
ture, composed mostly of hydrous-layer silicates of aluminum referred to as