Waxes, soluble

Oil Content. The production of petroleum waxes involves the removal of oil therefore, the oil content (actually the percentage of oil and low molecular weight fractions) is one indication of the quaUty of the wax. Oil content is deterrnined (ASTM D721) as that percentage of the wax soluble in methyl ethyl ketone at —31.7 C. 

It would seem, therefore, that particularly with oil- and wax-soluble insecticides the older concepts of surface residues on plant tissues should be revised in terms of extrasurface—i.e., above the cuticle—and subsurface—i.e., within or below the cuticle— residues. The latter would in turn be subdivided into cuticular residues and various intracarp residues. 

Basically, the process employs a selective solvent or mixture of solvents which have adequate oil solubility to permit operation at reduced temperatures without the separation of a second liquid or oil phase and in which the wax solubility is so low that the resulting dewaxed oil pour point is substantially the same as or within a few degrees of the dewaxing temperature. Generally, the solvent employed is a mixture of an aromatic solvent to obtain the required oil solubility and a polar solvent—for example, a ketone— to produce highly crystalline, easily filterable wax. 

An area of interest at that time was the incorporation of colloidal silica into emulsion systems. Typical emulsions included floor waxes or rubber latices. Conventional wax compositions ordinarily included certain extenders or modifiers in the wax dispersions. These may comprise wax-soluble or water-dispersible resins (natural or synthetic). These formulations can produce coatings with a pleasing appearance however, many lack slip resistance. The incorporation of colloidal silica into the formulation produces coatings that prevent slipping. 

Solvent Wax Solubility g/100 ml Viscosity 0°C,cSt BP, C Latent Heat of Vaporization, cal/g Specific Heat, caVg-°C... 

MEK/MIBK refrigeration requirements are lower than MEK/Toluene because the Pour-Filter spread is smaller due to the lower wax solubility. The Pour-Filter spread is the difference between the Dewaxed Oil pour point and the filtration temperature required to meet the Dewaxed Oil pour point specification. Wax has a higher solubility in Toluene than MIBK and MEK/Toluene systems will require a lower filtration temperature to achieve the same pour point. MEK/MIBK solvent mixture viscosity is lower than MEK/Toluene. Filtration rates are higher for MEK/MIBK. Toluene costs less than MIBK. 

The efficacy of the PE-PEP diblock additives at preventing the formation of waxy gels in oil upon cooling below the wax solubility limit was studied by yield stress measurements in parallel with optical microscopy observations [15]. The effect of a lowMw diblock (1.5-5 K) on the yielding properties of waxy gels at a 4% wax level at 0 °C is shown in Fig. 31 for the different wax molecules considered. All gels display similar behavior with increasing additive concentration. At low polymer addition, the yield stresses of the gel drop... 

Comparing the wax solubility lines (Fig. 47) with the temperature evolution of the scattered intensity from PEB-n random copolymers in d-decane (Fig. 37) we observe that a good match of the wax and polymer aggregation tendency occurs if, e.g., small amounts of C24 wax (<2%) are mixed with the PEB-11 copolymer, or if larger amounts of 35 wax are mixed with PEB-7.5 copolymer. In these cases a cocrystallization of wax and polymer in common structures could possibly take place. For this reason detailed SANS studies of such wax-polymer mixtures for different contrast conditions (according to Eq. 11) were done in order to elucidate the interaction mechanism taking... 

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