PARAFFIN WAX
Paraffin wax is a soft colorless solid, derived from petroleum, coal or oil shale, that consists of a mixture of hydrocarbon molecules containing between twenty and forty carbon atoms. It is solid at room temperature and begins to melt above approximately 37 °C (99 °F) its boiling point is >370 °C (698 °F) Common applications for paraffin wax include lubrication, electrical insulation, and candles; dyed paraffin wax can be made into crayons. It is distinct from kerosene and other petroleum products that are sometimes called paraffin
UN-dyed, unscented paraffin candles are odorless and bluish-white. Paraffin wax was first created in 1830 in Germany, and marked a major advancement in candle making technology, as it burned more cleanly and reliably than tallow candles and was cheaper to produce
In chemistry, paraffin is used synonymous with alkane, indicating hydrocarbons with the general formula CnH2n+2. The name is derived from Latin parum (“barely”) + affinis, meaning “lacking affinity” or “lacking reactivity”, referring to paraffin’s nonreactive nature
Application
In industrial applications, it is often useful to modify the crystal properties of the paraffin wax, typically by adding branching to the existing carbon backbone chain. The modification is usually done with additives, such as EVA co polymers, micro crystalline wax, or forms of polyethylene. The branched properties result in a modified paraffin with a higher viscosity, smaller crystalline structure, and modified functional properties. Pure paraffin wax is rarely used for carving original models for casting metal and other materials in the lost wax process, as it is relatively brittle at room temperature and presents the risks of chipping and breakage when worked. Soft and pliable waxes, like beeswax, may be preferred for such sculpture, but “investment casting waxes,” often paraffin-based, are expressly formulated for the purpose.
In a pathology laboratory, paraffin wax is used to impregnate tissue prior to sectioning thin samples of tissue. Water is removed from the tissue through ascending strengths of alcohol (75% to absolute) and the tissue is cleared in an organic solvent such as xylene. The tissue is then placed in paraffin wax for a number of hours and then set in a mold with wax to cool and solidify; sections are then cut on a micro-tome.
