A toolbox for the characterization of biobased waxes

Abstract

Waxes are a diverse class of molecules with numerous industrial, commercial, household, medical, and personal applications. Despite the wide variety of applications and chemical structures, most waxes are currently classified entirely by their melting and congealing points. This limits the ability to compare wax performance across the literature and impedes efforts at improving the physical functionality of biobased wax mimetics; many applications require waxes with specific physical properties that cannot be correlated to congealing or melting points alone. A toolbox of procedures to characterize and compare waxes based on not only their melting and congealing points, but also the hardness, yield force, viscosity, and solid fat content is presented. This comprehensive toolbox for the characterization of waxes provides a detailed assessment of their individual functional properties and provides an important tool for holistic comparisons of types of waxes based on their performance. This toolbox is especially useful for analyzing and finding potential applications for the next generation of emerging renewable waxes which are being introduced to the market. Practical applications: An increasing number of lipid derived waxes are entering the market. This toolbox provides a set of reproducible and useful experiments which can be used to analyze and compare the properties of waxes. By focusing on properties relevant to a wide range of wax applications, both end users and suppliers can quickly screen new waxes and determine their applicability for specific functions. This is presently not accomplished using only the ASTM standards of the industry. A wax toolbox containing a series of reproducible methods are presented for determining the melting point, congealing point, hardness, yield force, viscosity, and solid fat content of waxes. This toolbox is especially useful for characterization and comparison of waxes based on their functional performance, and can be used to predict the suitability of waxes for specific applications.

Lipid‐derived monoamide as phase change energy storage materials

“…This singularity designates the point at which the liquid sets when cooled, ie, the congealing point. 36,47 The congealing temperature versus chain length of the monoamides (circles in Figure 6D) follows a sigmoidal curve characterized by a marked step between two plateaus (C26-C28 and C34-C36) similar to what was observed for the crystallization temperature ( Figure 5A). It is, in fact, the same competing influence of mass transfer, hydrogen bond strength, and van der Waals which drives the variation of both parameters.…”

“…The viscosity‐temperature profiles of the monoamides present a marked deviation from the continuous viscosity‐temperature flow curve (indicated with an arrow in Figure B for C36). This singularity designates the point at which the liquid sets when cooled, ie, the congealing point . The congealing temperature versus chain length of the monoamides (circles in Figure D) follows a sigmoidal curve characterized by a marked step between two plateaus (C26‐C28 and C34‐C36) similar to what was observed for the crystallization temperature (Figure A).…”

Stabilization of an Aqueous Bio-Based Wax Nano-Emulsion through Encapsulation

“…The biowax composition contains a more complex mixture of molecular chains than synthetic waxes, including substituted long-chain aliphatic hydrocarbons with alkanes, alkyl esters, fatty acids, primary and secondary alcohols, diols, ketones and aldehydes [ 2 ]. The variation in chemical functionalities and molecular weight finally determines the ultimate properties, while specific physical properties cannot uniquely be correlated to the melting point [ 3 ]. Fossil-based waxes (e.g., paraffin wax) are usually produced as a by-product of oil refining and distillation, and the properties for industrial use are strongly affected by a residual oil content [ 4 ].…”

Formation of wax walled microcapsules via double emulsion using cross membrane emulsification at elevated temperatures

“…To be doubly sure that the XME could cope with a range of waxes mineral oil was used again but at 95°C with the emulsion (Figure 5c) having two peaks: at 1.4 and 16 µm. The increase in the flux (90.9 ml/min at 95°C compared with 26.0 ml/min at 80°C and 9.8 ml/min at 60°C) (Table 1), can be attributed to the expected change in viscosity with temperature (Floros 2017) having an effect on the flux (Williams et al 2010).…”