Paraffin-based waxes, petroleum

A widely used classification of petroleum distinguishes between crude oils either on a paraffin base or on an asphalt base and arose because paraffin wax separates from some crude oils on cooling, whereas other oils show no separation of paraffin wax on cooling. The terms paraffin base and asphalt base were introduced and have remained in common use (van Nes and van Westen, 1951). 

Petroleum crude oils, which are divided for the purposes of conventional classification into three main types—asphalt (or naphthenic)-base, paraffin-base, and mixed-base—contain varying amounts of hydrocarbons which readily solidify and are identified as wax. The asphalt-base crudes may contain only a trace of wax, while the wax content of the paraffin-base crudes and the mixed-base crudes may be as high as 15% or higher (73). Crude oils with a wax content as high as 35% are known. 

PEG bases can also be combined with various other bases. They are compatible with cetyl alcohol, cetyl stearyl alcohol, stearic acid, 1,2-propylene glycol, glycerol, glycerol monostearate, and PEG sorbitan monooleate. PEGs are not compatible, however, with paraffin wax, petroleum jelly, oleyl oleates, and hydrogenated peanut oil. Eurther details on the miscibility and compatibility of PEGs with other substances are given in Table 5. 

Waxes made from hydrogenated or partially hydrogenated soybean oil have gained traction for use in candles and other applications as natural alternatives to petroleum-based paraffin waxes. These products can compete on a cost basis when crude oil prices are high, but even during periods of relatively low-cost petroleum, the soy-based waxes can capture a segment of the overall market that is willing to pay a premium for a natural product. 

A paraffin wax is a petroleum wax consisting principally of normal alkanes. MicrocrystalHne wax is a petroleum wax containing substantial proportions of branched and cycHc saturated hydrocarbons, in addition to normal alkanes. SernimicrocrystaUine wax contains more branched and cycHc compounds than paraffin wax, but less than microcrystalHne. A classification system based on the refractive index of the wax and its congealing point as... 

Plasticizers and Processing Aids. Petroleum-based oils are commonly used as plasticizers. Compound viscosity is reduced, and mixing, processing, and low temperature properties are improved. Air permeabihty is increased by adding extender oils. Plasticizers are selected for their compatibihty and low temperature properties. Butyl mbber has a solubihty parameter of ca 15.3 (f /cm ) [7.5 (cal/cm ) ], similar to paraffinic and naphthenic oils. Polybutenes, paraffin waxes, and low mol wt polyethylene can also be used as plasticizers (qv). Alkyl adipates and sebacates reduce the glass-transition temperature and improve low temperature properties. Process aids, eg, mineral mbber and Stmktol 40 ms, improve filler dispersion and cured adhesion to high unsaturated mbber substrates. 

Lipophilic ointment (oil ointment) consists of a lipophilic base (paraffin oil, petroleum jelly, wool fat [lanolin]) and may contain up to 10 % powder materials, such as zinc oxide, titanium oxide, starch, or a mixture of these. Emulsifying ointments are made of paraffins and an emulsifying wax, and are miscible with water. 

The category of pure hydrocarbons has too many materials to list. Anything that is typically burned to produce heat or energy can be applied as a fuel for an IE mixture. Some high-profile examples would include petroleum products such as diesel fuel and kerosene, plant- and animal-based oils, sugars, glycerin, wax/paraffin, sawdust/wood pulp, Vaseline, shellac, and rosin. 

Because the paraffin and mixed-base crudes yield lubricating oil fractions of high quality, means had to be devised in the early days of the petroleum industry to separate the wax from the oil. The removal of wax from petroleum fractions is one of the most important phases in the production of lubricating oils and fuel oils of low pour point, and has received the attention of many investigators. 

Bullet lubricants frequently contain mixtures of some of the following beeswax, petroleum jelly, sheep tallow, carnauba wax, molybdenum disulfide, lithium base grease, ceresin wax, powdered graphite, paraffin wax, Alox compound, and Zokorite. The mixture may be dissolved or suspended in a fast-drying solvent or applied directly while hot. 

The composition of beeswax varies by insect species and by what the bees have been eating. Beeswax has a low melting point, and is often cast into useful or decorative shapes. Combined with resins, it was used as a water-proofing and adhesive. It has been used as a coating on paintings and furniture, to enhance the appearance of and to protect the surfaces from moisture. It was used as a water-repellent and adhesive in ships and boats. Beeswax has been applied to fabric, cordage, and hair to add luster and increase water-resistance, and as a base for cosmetic and medicinal creams and lotions. Beeswax was the primary and best available material for making candles until the invention of paraffin wax, which is a by-product of the distillation of petroleum. 

Detergents, which now rival soap in demand, are based largely on petroleum the variety of structures which confer detergent properties have led to some interesting syntheses. Alkyl aryl sulfonates are made by alkylation of benzene either with chlorinated kerosene or with a highly-branched olefin made from propylene. Long chain olefins for secondary sulfates were made from paraffin wax. Secondary alkyl sulfonates were made by direct sulfonation of paraffins with sulfur dioxide and chlorine, a reaction discovered in America in the 193O s. 

Attempts have been made to define or classify petroleum based on various distillation properties when combined with another property such as density. It has been suggested that a crude should be called asphaltic if the distillation residue contained less than 2% wax and paraffinic if it contained more than 5%. A division according to the chemical composition of the 250-300°C (480-570°F) fraction has also been suggested (Table 2.1). 

Naphthene oils are heavier and higher in viscous, volatile lubricating oils. Naphthene oils have an asphalt base since distillation produces solid and semi-solid asphalt residues. Lower densities and residues of petroleum or paraffin wax are a characteristic of paraffin oils. 

Most lubricants are made from natural raw materials paraffins from petroleum residues, lignite carbonization, or bimminous shales the natural fatty acids (Cje to Cl 8 acids and mixtures of same), vegetable and animal fats. Further hydration of the fatty acids results in fatty alcohols. The most effective lubricants in technical terms, as well as the most expensive lubricants, are refined mmitanic waxes (C28-C32). Semisynthetic lubricants are based on the conversion of alcohols to esters, metal oxides or hydroxides to salts or amines to amides. FuUy S3mthetic waxes include low molecular PE and PP waxes or copolymers made from ethylene, VAC, acrylic, or crotonic acid. 

The requirements for static ozone resistance vs. dynamic ozone resistance are very different, so that choiee of antiozonant depends greatly on the expected service of the rubber produet. Static protection is provided by petroleum waxes, usually paraffin and/or microcrystalline waxes. The waxes work by blooming to the rubber surface to form a physical barrier to ozone attack. The choice of wax or wax blend is based upon migration temperature where mobility and solubility of the wax in the rubber are balanced so that sufficient bloom occurs for optimum protection. Because the wax film is inextensible, it will rupture under deformation and expose the elastomer. Waxes protect only under static conditions. 

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