Paraffin Blend Research Articles

Effects of diluent content on the crystallization behavior and morphology of polyethylene membrane fabricated via thermally induced phase separation process

Thermally induced phase separation technique has been widely applied to produce various commercial high-density polyethylene (HDPE) membranes based on the HDPE/diluent system. In this work, the crystallization behavior and morphological evolution of HDPE/liquid paraffin (LP) blends were systematically investigated by differential scanning calorimetry (DSC), dynamic thermomechanical analysis (DMA), two-dimensional small-angle X-ray scattering (2D-SAXS) and scanning electron microscope (SEM). It is found that the chain mobility of HDPE is promoted and the entanglement density reduces with the introduction of diluent LP. When the LP content is lower than 40%, the liquid diluent distributes randomly in HDPE melt, while as the LP content exceeds 40%, the diluent saturates the inter-molecular space of HDPE, resulting in the full growth of lateral lamellar dimension of PE crystal. On the other hand, the morphologies of HDPE/LP films change considerably with the diluent content. (1) LP content <20%: diluent lives directly in the inter-lamellar region; (2) 20% ≤ LP content ≤40%: diluent will be excluded into the inter-cluster region and leads to the formation of separated LP domains between PE clusters. (3) LP content >40%: diluent will be aggregated between the stacked clusters to create numerous interconnected LP domains which act as the pathways for the gas or liquid permeation after the removal of LP. Accordingly, we provide a new guidance for the condensed structure controlling and the development of PE membranes with diverse functionalities.

Experimental investigation and numerical simulation for structural evolution and stress distribution during the stretching process

AbstractIn the preparation of polyethylene (PE) microporous membrane, the stretching process of PE/liquid paraffin (LP) blend is of great significance for improving the mechanical properties and optimizing the pore size and its distribution. In this study, we have adopted a method that combines experimental investigation and numerical simulation to explore crystal structure transformation and residual stress distribution of PE matrix during the stretching process. First of all, the X‐ray diffraction, small‐angle X‐ray scattering test, and tensile strength test are used to analyze these PE/LP blend samples that are processed at different stretching temperatures (110°C, 115°C, 120°C, 125°C) and different stretching ratios (2 × 2, 3 × 3, 4 × 4, 5 × 5). It is found that a higher temperature or larger ratio is beneficial for crystallizing of PE long chains and affecting the tension strength. After the extraction process, the obtained PE microporous membranes have more uniform pore size distribution and an increased pore diameter according to the results of scanning electron microscopy and porosity test. It is attributed to the fact that residual stress is more easily stored in the amorphous region of PE microporous membrane. PE microporous membranes can have higher crystallinity and well‐dispersed crystal region by controlling a matched temperature and ratio. It is inspired for optimizing the technological parameters in industrial production.

Morphology of porous UHMWPE originating from the S–L phase separation in UHMWPE/liquid paraffin (LP) blends

Morphology of porous UHMWPE originating from the S–L phase separation in UHMWPE/liquid paraffin (LP) blends

Investigation on the solid–liquid (S–L) phase separation of the PE/LP blend with different molecular weight polyethylene

The solid–liquid (S–L) phase separation occurs in the polyethylene (PE)/liquid paraffin (LP) blend, which exhibits different characteristics for the molecular weight of PE. Herein, we have studied the S–L phase separation process of PE-500 (molecular weight of 5,000,000)/PE-60 (molecular weight of 600,000)/LP melts by the hot-stage-optical device. It is found that the clarification temperature and cloud temperature of PE-500/PE-60/LP blend decreased with the addition of PE-60. The isothermal crystallization behavior of these ternary blends is explored further using differential scanning calorimetry (DSC). According to the analysis results of Avrami equation and Arrhenius equation, the exponent n increases from 1.23 to 2.42 at higher temperature, indicating that the melt with high PE-60 content have a growth pattern between two and three dimensions, which could lead to larger pore. The activation energy at high temperature increases from 738.568 to 1321.259 $$ {\text{kJ}}/{\text{mol}} $$ with enhancing PE-60 content, while the activation energy decreases from 209.689 to 36.608 $$ {\text{kJ}}/{\text{mol}} $$ at lower temperature. It demonstrates that PE-60 content is not conducive to nucleation at high temperatures, but in favor of growth at low temperature. We believe the pore structure of PE microporous membrane may be controlled by different ratios of PE-500/PE-60 and crystallization temperature.

The use of infrared spectroscopy and thermal analysis for the quick detection of adulterated beeswax

Beeswax samples of different origins were evaluated for their authenticity by infrared spectroscopy and thermal analysis. The Fourier Transform Infrared Spectroscopy (FT-IR) method was used for the genuineness assessment and the melting process was examined using the differential scanning calorimetry (DSC) method. Eight suspicious beeswax samples delivered by local beekeepers were examined. As reference standards, pure authentic beeswax standards, pure paraffin, and wax-paraffin blends were used. The comparison of the infrared spectra of tested wax samples and references allowed the identification of adulterated wax samples based on the differences in the spectra fingerprint region (700 to 1800 cm−1), especially 1170 and 1735 cm−1 bands. Moreover, the ratio of the 1735 and 2850 cm−1 band area (lower than 0.5) was used as an indicator of wax adulteration. Among the 8 samples studied, 3 were found to have been falsified with paraffin. The thermal analysis confirmed the adulteration of the same wax samples. The melting temperatures determined in these cases were lower (52.3 to 57.7) as compared to other samples (63.1 to 65.9), identified as real beeswax by comparison to standards (63.8 to 64.7). A similar tendency during the re-heating of cooled wax samples was observed, which suggested the addition of paraffin or another substance with a lower melting point to adulterated waxes. The methods used in this research (FT-IR and DSC) allowed for a relatively quick, easy, and inexpensive verification of the authenticity of the beeswax. Such a method can be used as a screening step before a comprehensive GC analysis of beeswax.

Effects of cooling process on the solid–liquid phase separation process in ultra-high-molecular-weight polyethylene/liquid paraffin blends

Ultra-high-molecular-weight polyethylene (UHMWPE) microporous membrane is generally prepared by thermally induced phase separation process. The phase separation process is closely related to the cooling process in practical production. In this paper, the phase separation temperature of UHMWPE/liquid paraffin blends was explored by the hot-stage-optical device and differential scanning calorimeter (DSC), and the result showed that the temperature was about 105–125 °C. The effects of cooling condition and crystallization ability of UHMWPE on the separation process of the blends were also investigated by DSC. The results showed that the phase separation was affected by the cooling rates rather than the initial cooling temperature. And the crystallization of UHMWPE was mainly limited by the nucleating at a low cooling rate, which could form larger porous structure. In a word, it should be inspirational for the actual production of the UHMWPE microporous membrane. The solid–liquid phase separation will occur in the cooling process of UHMWPE/LP blends, which is driven by the external temperature difference. It is significant to understand the phase separation process. In this paper, the effects of the melting properties and cooling condition on phase separation process were investigated, the S–L phase separation range is at 105–125 °C, and the speed of phase separation is mainly related to the external temperature difference and the UHMWPE content. It could be inspirational for actual production of the UHMWPE membrane with more uniform pore structure.

Numerical Simulation and Optimization of the Melting Process of Phase Change Material inside Horizontal Annulus

Latent heat storage (LHS) technologies adopting phase change materials (PCMs) are increasingly being used to bridge the spatiotemporal mismatch between energy production and demand, especially in industries like solar power, where strong cyclic fluctuations exist. The shell-and-tube configuration is among the most prevalent ones in LHS and thus draws special attention from researchers. This paper presents numerical investigations on the melting of PCM, a paraffin blend RT27, inside a horizontal annulus. The volume of fluid model was adopted to permit density changes with the solidification/melting model wherein natural convection was taken into account. The eccentricity and diameter of the inner tube, sub-cooling degree of the PCM, and the heating-surface temperature were considered as variables for study. Through the evaluation of the melting time and exergy efficiency, the optimal parameters of the horizontal annulus were obtained. The results showed that the higher the heating boundary temperature, the earlier the convection appeared and the shorter the melting time. Also, the different eccentricity and diameters of the inner tube influenced the annulus tube interior temperature distribution, which in turn determined the strength and distribution of the resulting natural convection, resulting in varying melting rates.

Experimental investigation of a latent heat storage for solar cooling applications

The paper presents the realization and experimental characterization of a lab-scale latent heat storage, specifically developed for solar cooling applications. The latent heat storage is based on a compact fin-and-tube stainless steel heat exchanger (HEX) and a commercial paraffin blend, having a nominal melting temperature of 82°C, suitable for solar cooling plants employing non-concentrating solar collectors technology. The realised heat storage has been experimentally characterised in lab, by means of a test rig able to simulate the working boundary conditions of a solar cooling plant. Charging and discharging tests have been performed both simulating a completed charge phase followed by a complete discharge phase, to analyse system efficiency and achievable energy storage density. Furthermore, dynamic tests, simulating short consecutive charge/discharge phases (with incomplete phase change), have been accomplished, to analyse the heat transfer efficiency inside the reactor. Main results confirmed that the heat storage density increases of about 50%, compared to sensible water storages. Satisfactory discharge efficiency, ranging between 45% and 60% has been obtained under analysed working conditions. Average discharging power between 0.7 and 1.2kWhas been measured, which confirms the necessity to further optimize the HEX efficiency as well as the thermal conductivity of the employed PCM.

Fluid emulsion base potential of shea butter

The potential of shea butter (SB) as base for fluid, soap-stabilized emulsion and the stability of such formulations have been studied. Stability features (homogeneity, viscosity) of SB/Liquid paraffin (LP) blends containing 1–50 %w/w of SB at ambient temperature were determined to locate the threshold concentration range for fluid outcome. SB emulsion formulations were prepared from the fluid SB/LP blends by homogenizing each at 1:9 ratio (v/v) with potassium hydroxide (KOH) aqueous solution (0.1, 0.2, 0.4, or 0.6 M concentration, respectively), and with 0.2 M KOH at different mixing ratios (2:8, 3:7, 4:6, or 5:5 v/v), respectively. The physical consistency and stabilitycharacteristics (redispersibility, creaming or breaking) of the formulations were studied at room temperature over 12 weeks. The mean disperse-phase globule size and viscosity of formulation samples stable for ≥8 weeks were determined. SB/LP blends containing 1–20 %w/w SB were pourable liquids; SB separated out as sediment from the fluid blends left to stand for 48 h. Higher concentrations solidified. Fluid emulsions were produced at 0.5–18.0 %w/w SB concentrations, having mean globule size of 4.4–43.1 μm and viscosity of 153–1863 cP. The graded KOH concentrations gave emulsion products with different levels of stability. While some were unstable (broken, immobile) in storage, those formulated with 0.1 M KOH (153–354 cP viscosity) remained stable liquids throughout the 12 weeks of study. The best (most stable) formulation contained 4.5 %w/w SB emulsified with 0.2 M KOH.Keywords: Shea butter; Emulsion base; Fluid; Formulation

Study of Thermo-Mechanical Properties of HTPB–Paraffin Solid Fuel

The classic hybrid rocket which employs hydroxyl-terminated polybutadiene (HTPB) fuel is characterized by low ablation rate. To enhance the ablation rate, paraffin was added to the HTPB. The enhancement is due to the low viscosity and low surface tension of the surface melt layer of the paraffin during combustion. This paper reports the thermal properties, mechanical properties and ablation rate when HTPB was blended with different percentage of paraffin. The thermal stability of the blends was investigated using differential scanning calorimetry (DSC) and thermogravimetry analysis with constant heating rate 27Kmin−1 under argon atmosphere. The thermal stability of the blends decreased with the increase in paraffin content. The constant pressure specific heat capacities ( $${C_{\rm p})}$$ of the fuel blends were measured using DSC in the temperature range of 80–250 $${{\circ}}$$ C. The theoretical model of the ablation rate of HTPB–paraffin blends using activation energy, pre-exponential factor and $${C_{\rm p}}$$ was studied. The results indicated a higher regression rate of 6–33% with the increase in paraffin. The combustion enthalpy of HTPB blended with paraffin is determined by oxygen bomb calorimeter at a constant volume. The standard combustion enthalpy of pure HTPB and paraffin was found to be 37.9 and 41.9MJkg−1. The data revealed that blending of HTPB with paraffin, resulted an increase in the heat of combustion by 2–9%. The blending of the paraffin will reduce the mechanical strength. Studies were also carried out to find out the dynamic mechanical properties as the result of blending paraffin to HTPB using dynamic mechanical analysis. The temperature was held constant at room temperature and the frequency scan ranged from 1 to 10Hz in steps of 1Hz. The results show that the presence of paraffin in HTPB binder has considerable effect on the dynamic response of the material.

Thermodynamics of semicontinuous n-alcohol/ultra-low sulfur diesel blends

Two methods for calculating activity coefficients of ultra-low sulfur diesel (ULSD) and its blends with pure alcohols (C1–C5), namely, UNIFAC-continuous and UNIFAC-Dortmund-continuous, are presented. ULSD was modeled as a continuous blend of paraffins, naphthenes, and aromatics. The molar distribution in each family was expressed as a function of carbon number using the gamma distribution function. The parameters of the distribution function can be easily fitted from experimental distillation data of ULSD and extrapolated to n-alcohol/ULSD blends. The activity coefficients obtained were used to model the ASTM D86 distillation curves. UNIFAC-Dortmund-continuous exhibited the best fitting to the experimental results. Based on that, three new correlations for calculating the boiling point, vapor pressure and structural groups of complex ULSD are proposed here.

Development of polystyrene-based films with temperature buffering capacity for smart food packaging

One of the main factors affecting the quality of perishable products is represented by temperature variations during storage and distribution stages. This can be attained through the incorporation of phase change materials (PCMs) into the packaging structures. PCMs are able to absorb or release a great amount of energy during their melting/crystallization process and, thus, they could provide thermal protection to the packaged food. Thus, the objective of this research was to develop polystyrene (PS)-based multilayer heat storage structures with energy storage and hence temperature buffering capacity for their application in refrigerated foods. To this end, polycaprolactone (PCL) was used as the encapsulating matrix of a phase change material (PCM) called RT5 (a commercial blend of paraffins with a transition temperature at 5°C), by using high throughput electrohydrodynamic processing. The PCL/PCM fibrous mats were directly electrospun onto PS films and an additional PCL electrospun layer (without PCM) was also deposited in some experiments to improve the overall functionality of the PCM. The attained morphology, thickness, deposition time, temperature and multilayer structure played an important role on the energy storage capacity of the developed PS-based multilayer structures. Results obtained from a differential scanning calorimeter (DSC) show that RT5 can be properly encapsulated inside the PCL matrix and the encapsulation efficiency and, thus, the heat storage capacity was affected not only by the multilayer structure, but also by the storage time and temperature. The thermal energy storage/release capacity was of about 88–119J/g. As a result, this work demonstrates the potential of these materials for an efficient temperature buffering effect of relevance in food packaging applications, in order to preserve the quality of refrigerated packaged food products.

Polyethylene/paraffin binary composites for phase change material energy storage in building: A morphology, thermal properties, and paraffin leakage study

Phase change materials (PCMs) are able to melt and solidify at a certain temperature with a high heat of fusion. These promising functional materials for acting as energy as latent heat storage units have one major problem, leakage of the PCMs when molten. Polymer/phase change material (PCM) blends were investigated as a possible solution of PCM leakage. In this research, paraffin was used as the PCM and three types polyethylene (PE) were used as the structural matrix. To investigate the morphology of PE/ paraffin blends and evaluate the influence on blend behavior, paraffin was blended with either high density polyethylene (HDPE), low density polyethylene (LDPE), or linear low density polyethylene (LLDPE) using a parallel co-rotating twin screw extruder. Chloroform extraction was utilized to estimate the maximum amount of paraffin able to be released by the PE network at equilibrium. Scanning electron microscope (SEM) images of chloroform-extracted samples were collected to investigate the blend structure. Thermal transition temperatures and crystallinity of components in the blends were characterized by differential scanning calorimetry (DSC) and polarized optical microscopy (POM) was used to investigate crystal perfection changes of the polyethylenes before and after blending with paraffin. Paraffin leakage of the blends was investigated by accelerated degradation test in an oven at 60°C. The leakage behavior was analyzed by Korsmeyer–Peppas equation to determine the underlying mechanisms. Chloroform extraction indicated that almost all the paraffin would leak out from the blends in the long run. A co-continuous structure of the blends was evident from the chloroform extraction and subsequent SEM images. While this co-continuous structure controlled leakage behavior, it had little influence on paraffin thermal transition temperatures and crystallinity based on DSC study. In contrast, PE crystal perfection decreased with paraffin level as evident in POM images. This structure resulted in leakage of paraffin in all formulations.

Use of phase change materials to develop electrospun coatings of interest in food packaging applications

In the present study, a heat management PS foam tray containing an ultrathin fiber-structured PS/PCM coating was prepared by using high throughput electrohydrodynamic processing. To this end, polystyrene (PS) was used as the encapsulating matrix of a commercial phase change material (PCM) called RT5 (a blend of paraffins with a transition temperature at 5°C), by using the electrospinning technique. With the aim of imparting heat management capacity to the trays, the PS tray was coated by the PS/PCM ultrathin fiber mats and a soft heat treatment was applied to improve the adhesion between the layers. Results showed that RT5 could be properly encapsulated inside the PS matrix, with a good encapsulation efficiency (ca. 78%) and the developed PS fibers had a heat storage capacity equivalent to ∼34wt.% of the neat PCM. The effect of storage time and temperature was evaluated on the heat storage capacity of the developed PS-trays with the ultrathin fiber-structured PS/PCM layer. The heat storage capacity was affected not only by the storage time, but also by the temperature. This work adds a new insight on the development of heat management polymeric materials of interest in food packaging applications, in order to preserve the quality of refrigerated packaged food products. Although the electrohydrodynamic processing seems to be a promising alternative to develop heat management materials, further works will be focused on the improvement of heat storage capacity and efficiency of the developed packaging materials along storage time.

Thermal decomposition study of HTPB solid fuel in the presence of activated charcoal and paraffin

The hydroxyl terminated polybutadiene (HTPB)—paraffin blend is a potential fuel for hybrid rockets. Research on this solid fuel has been sporadic for the last three decades. In the present work thermal analysis has been conducted on the fuel to study the effect of heat on a series of HTPB in the presence of activated charcoal and paraffin in a dynamic helium atmosphere using differential scanning calorimeter at heating rates varying from 3 to 43 K min−1. The activated charcoal did not show any effect on the HTPB decomposition curve and the samples were behaving like a pure HTPB thermal decomposition curve. The pronounced effect of blending the HTPB with paraffin was observed with a lowering of the activation energy, 20 % decrease for the HTPB with 12.75 % paraffin. The net heat release for the pure HTPB is found to be 878 J g−1 and a decrease of 40 % of heat release is observed in the sample with 12.75 % paraffin. The Arrhenius parameters were established according to the Kissinger method and the pre-exponential factor and the rate constant were also estimated. These experimental findings indicate that HTPB-paraffin-based fuel provides a good opportunity to satisfy a broad range of mission requirements for the next generation of hybrid rockets.

The melting of phase change material in a cylinder shell with hierarchical heat sink array

Temporal and spacial mismatch between thermal energy supply and consumption occurs in many industrial processes, like harvesting thermal energy from intermittently ejected exhaust gas. To even out this mismatch, heat exchangers filled with phase change materials (PCMs) are widely accepted. Up till now, most of the heat exchangers take the shape of an annulus, or shell and tube design with uniform tubes, which may not be the ideal structures for their purpose. In this paper, a shell and tube design with hierarchical tube array in place of the uniform tubes is proposed and studied. The shell is assumed to possess a fixed temperature and negligible thickness. The tube arrays, where still water is stored, are assumed to be heat sinks with no fluid movement. Inside the shell, one tube is placed at the centre, forming the higher hierarchy; multiple other tubes encircle the central tube, forming the lower hierarchy. A paraffin blend, RT27, is filled in between. We investigate systematically the advantage of this new design over the annulus. Two structural parameters are explored numerically: the number of lower hierarchy pipes n and the ratio of higher hierarchy tube diameter to lower hierarchy tube diameter r. The results of changing the parameters are analysed in terms of paraffin melting time, water heating speed and exergy efficiency, in both dimensional and dimensionless forms. We show that the paraffin melting time is shortest for combination n = 2, r = 2. Also, during the unstable melting process, exergy efficiency fluctuates differently for different cases, but merges together ultimately.

Miscibility studies of paraffin/polyethylene blends as form-stable phase change materials

Thermal energy storage is useful to promote energy conservation in buildings or machinery. One means of achieving a form stable phase change materials (PCMs) with polymers is to utilize immiscible blend pairs, governed by blend miscibility. The degree of miscibility between the polymer pairs may also influence energy efficiency in applications. Binary polyethylene–paraffin blends were melt compounded at different ratios of high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE) using a parallel co-rotating twin screw extruder. The miscibility of the paraffin in the three types of polyethylene was evaluated using differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The DSC data demonstrated two melting temperatures with a depression of the equilibrium melting temperature for the polyethylene in the mixture. Two distinct and an intermediate phase were evident in the atomic force microscopy images. This structure verified the partial miscibility of paraffin in polyethylene. Interaction parameters between paraffin and polyethylene were obtained through melting point depression analysis via the Flory–Huggins approximation for thermodynamic mixing of two components. The crystallinity of each component depends upon the blend concentration. Two paraffin crystallization peaks for the PE/paraffin blends were observed, with the enthalpy of one peak increasing at the expense of the other. The lowest paraffin miscibility in polyethylene is found in paraffin/HDPE blend.

Study on preparation and thermal energy storage properties of binary paraffin blends/opal shape-stabilized phase change materials

The binary paraffin blends/opal composites as shape-stabilized phase changed materials were prepared by adsorbing binary paraffin blends into the natural porous opal. In this study, binary forms of three commercial paraffins (n-octadecane, paraffin wax and liquid paraffin) with different melting temperatures were compound together by the fusion method, and the optimum mixed proportions were determined through differential scanning calorimetry (DSC) analysis. Raw opal was thermally treated in order to improve the adsorption capacity of opal before using as the supporting material. The microstructure and chemical structure of the binary paraffin blends/opal composites were characterized by scanning electronic microscope (SEM) and Fourier transformation infrared (FT-IR) spectroscope. From the FT-IR analysis, there was no chemical interaction between binary paraffin blends and opal. The SEM results showed that the pore size of calcined opal among particles was improved after calcination, and the paraffin blends were well adsorbed and dispersed into the porous structure of the opal because of the capillary effect and physical surface tension forces. There was no leakage of the liquid paraffin from the composites even in the melting state. The thermal properties and thermal stability were investigated by DSC and a thermal cycling test, respectively. The DSC results showed that the phase-transition temperature and the latent heat of the PN2/calcined opal composite PCM were 24.91°C and 59.04±0.84J/g, respectively, which was suitable to be used as the indoor thermal energy storage building material. The thermal cycling test results indicated that the prepared sample was thermally reliable and chemically stable.

Kinetic Study of the Thermo-Oxidative Degradation of Squalane (C30H62) Modeling the Base Oil of Engine Lubricants

On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in exhaust gas recirculation (EGR) diesel engines, an experimental investigation was aimed to develop a kinetic model, which can be used for the prediction of lubricant oxidative degradation correlated with endurance test conducted on engines. Knowing that base oils are a complex blend of paraffins and naphthenes with a wide range of sizes and structures, their chemistry analysis during the oxidation process can be highly convoluted. In the present work, investigations were carried out with the squalane (C30H62) chosen for its physical and chemical similarities with the lubricant base oils used during the investigations. Thermo-oxidative degradation of this hydrocarbon was conducted at atmospheric pressure in a tubular furnace, while varying temperature and duration of the tests in order to establish an oxidation reaction rate law. The same experimental procedures were applied to squalane doped with two different phenolic antioxidants usually present in engine oil composition: 2,6-di-tert-butyl-4-methylphenol and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. Thus, the effect of both antioxidants on the oxidation rate law was investigated. Data analysis of the oxidized samples (Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry) allowed rationalization of the thermo-oxidative degradation of squalane. The resulting kinetic modeling provides a practical analytical tool to follow the thermal degradation processes, which can be used for prediction of base oil hydrocarbon aging. If experiments confirmed the role of phenolic additives as an effective agent to lower oxidation rates, the main results lie in the observation of a threshold temperature where a reversed activity of these additives was observed.

Thermal transitions in high oil content petroleum-based wax blends used in granular sport surfaces

Five waxes were extracted from five different synthetic horse race tracks in the United States. These tracks included two cool weather tracks (Kentucky and Northern California) and three warm weather tracks (Southern California). All of these tracks operate over a significant range of temperatures and some even have large temperature swings within a single day of operation. Waxes used in these surfaces are generally a blend of normal paraffins, hydrocarbon oil, and microcrystalline wax that most likely originated from a de-oiling process where the lower carbon distributions had been removed. In this work, a solvent separation was used to remove the wax from samples of material obtained from each of these five tracks after they had been used for at least 3 months. The drop melt temperatures of the wax separated from the five tracks ranged from 67 to over 84 °C. Gas chromatography (GC) tests showed n-paraffin mass percentages ranging from 31.4% to 37.9% with the more complex oil and microcrystalline isomers making up the remainder. The drop melt temperatures increased as the ratio of weight average molecular weights for normals and isomers for each wax approached one. GC carbon distributions spanned from approximately C22 to C67. Curves for waxes obtained using differential scanning calorimetry (DSC) for each wax also showed distinct thermal behavior. All of the waxes show indications of two thermal peaks; however, in several cases the peaks showed significant overlap. Two wax samples also had small tertiary peaks. One wax contains two well-defined GC distributions of n-paraffins (low and high number carbon) and isomers and is believed to be a blend of two different waxes. The first peak corresponds to paraffin wax melting temperature ranges while the secondary and tertiary peaks correspond to melting of high carbon number microcrystalline wax and other complex isomers containing high melting temperatures. The DSC melting transition temperatures for all the waxes studied were found to occur within expected operational temperature ranges for racing surfaces. The temperature range was obtained from a representative track over a 4-day period of operation. Given the observed changes in the properties of the waxes it is possible that the mechanical properties of the tracks will also change with temperature. The results from this analysis suggest important temperatures to consider for further analysis of the materials containing these high oil content waxes.