Structural Analysis of Paraffin Wax and Beeswax

Sample handling, coating and preparation for SEM cause sample alteration, which modifies its composition and morphology structure. Therefore, the quality of the micrographs obtained is affected as well. Figures 9.6 to 9.8 show the SEM micrographs for paraffin wax following three magnifications of 250, 1050, and 2000 respectively. Some micrographs are affected by charging that alters the brightness and contrast levels. For example, the bright spots in Figure 9.6 exhibit the charging effect due to the presence of electrons that did not penetrate the wax. Figures 9.9 to 9.11 illustrate the SEM micrographs for beeswax at three magnifications of 250,1100, and 2000 respectively. In these figures, the bright spots are more dominant than in the case of paraffin wax, which implies that beeswax is more resistant to electron storming by SEM than paraffin wax is. This indicates that beeswax has a lower electric conductivity than paraffin wax.

Regarding the wax morphology, Figures 9.6 to 9.8 expose the lamellar structure of paraffin wax, thus the corresponding sample consists of a blend of polymers.

Figure 9.6 Micrograph of paraffin wax sample, showing two distinctive shades, one darker with long chains and smaller oblongate shape, and lighter pattern, which is background. Condition: Vacc = 20kV, Mag = x250, WD = 12mm.
Structural Formula Paraffin Wax
Figure 9.7 Micrograph of paraffin wax sample, in detail, illustrating the long and short chains, as well as individual oblongated patterns that are more visible. The background is shown in lighter color. Condition: Vacc = 20 kV, Mag = xl.05 k, WD = 11.5 mm.

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Figure 9.8 Paraffin wax sample with 2000 magnification indicating that long chains consist of oblongated patterns joining together. Condition: Vacc = 20 kV, Mag = x2.00k, WD = 11.5mm.

A miscible blend of amorphous and crystalline polymers means a single phase in the melt and a tidy crystalline phase with a mixed amorphous region in the solid. Because of chain folding during crystallization, the crystal lamellae are formed. Their drastic growth typically leads to the formation of spherulites. Spherulites are ball-shaped, spherical masses of radiating crystal fibers. When the miscible blend is submitted to crystallization, the non-crystalline impurity is excluded from the crystalline area.

The paraffin wax is a solid crystalline mixture of solid hydrocarbons of high molecular weight ranging from C20 to C30 and higher, e.g., C36H74. It is derived from the portion of crude petroleum commonly designated as paraffin distillate, from shale distillate, or from hydrocarbon synthesis by low-temperature solidification and expression or by solvent extraction. It is distinguished by its solid state at ambient temperatures and relatively slight deformation even under considerable pressures. Paraffin-wax crystals are long and narrow and form in plates. In the fully refined grades, they are dry, hard, and glossy. Paraffin wax is characterized by its homogeneous constitution and distribution due to its refining process. Then, the separation between the polymers is complete in the paraffin wax samples as indicated in Figures 9.6 to 9.8.

Honeybees secrete beeswax in a liquid state at an ambient temperature. Then, it crystallizes at the same ambient temperature. It consists of various components and is characterized by long hydrocarbon chains. It is made largely of a blend of myricyl palmitate, cerotic acid and esters, and some high-carbon paraffins. This reveals the heterogeneous constitution and distribution of beeswax, due to its polymers diversity. According to Figure 9.9, the beeswax consists of superposed plates. At higher magnifications, the beeswax SEM micrographs (see Figures 9.10 and 9.11) display a pasty, colloidal, and cloudy structure due to the amorphous and heterogeneous nature of the polymers composing the beeswax.

Figures 9.9 to 9.11 prove that the multiple polymers in the beeswax did not separate. So, these polymers are still solidly interconnected, which explains the beeswax's toughness and resistance to electric conductivity. Beeswax is natural, and it is younger and fresher than paraffin wax because the former has a shorter pathway period than the latter. Beeswax does not undergo refining stages, whereas paraffin wax is extracted from crude petroleum after refining and purification.

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Figure 9.9 Micrograph of beeswax sample showing topographic variations on the surface. Condition: Vacc = 10 kV, Mag = x250, WD = 12.2mm.

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Figure 9.10 Beeswax sample with 1100 magnification. Closer observation of the beeswax surface with more details showing irregular ridges and valleys. Condition: Vacc = 20kV, Mag = xl.lOk, WD = 12.4mm.
Figure 9.11 Beeswax sample with 2000 magnification. Detail of the beeswax surface with well visible ridges and valleys, indicating that the sample is not very hard, based on visual observation. Condition: Vacc = 10 kV, Mag = x2.00 k, WD = 11.9 mm.

Continue reading here: Response to Uniaxial Compression

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