The main properties of paraffin are melting point, oil content and stability.
Melting point
Paraffin is a mixture of hydrocarbons, so it does not have a strict melting point like a pure compound. The melting point of the so-called paraffin wax,
It refers to the cooling of molten paraffin samples under specified conditions, when the temperature of the first period of stagnation occurs on the cooling curve.
All kinds of waxes require good temperature resistance for paraffin wax, that is, no melting or softening at certain temperature.
According to the conditions of use, the use of the region and the season and the use of environmental differences, the commodity paraffin has a series of different melting points.
The main factors that affect the melting point of paraffin are the weight of the selected raw materials, and the melting point of paraffin wax from heavier distillates is higher.
In addition, the oil content has a great influence on the melting point of paraffin wax. The more oil in paraffin, the lower the melting point is.
The oil content
Oil content refers to the amount of low melting hydrocarbons contained in paraffin wax. High oil content can affect the color and stability of paraffin and reduce its hardness.
Therefore, it is necessary to remove the oil wax from the decompression fractions to reduce the oil content by means of sweating or solvent.
However, a small amount of oil is required in most paraffin products, which is beneficial for improving the gloss and stripping performance of the products.
stability
Paraffin product in modelling or coating process, be in a long time in hot melt state, and contact with the air, if the stability is not good, easy oxidize metamorphism, color becomes deep, even send stink.
In addition, when used in light conditions paraffin wax will also turn yellow. Therefore, paraffin has good thermal stability, oxidation stability and light stability.
The main factors that affect paraffin stability are the trace amounts of non-hydrocarbon compounds and polycyclic aromatic hydrocarbons. In order to improve the stability of paraffin wax, it is necessary to refine the paraffin wax to remove these impurities.