It is understood: paraffin, colorless to white translucent lumps, Pure paraffin is white, while paraffin containing impurities is yellow, tasteless, odorless, and greasy. Soluble in ether, chloroform, benzene, petroleum ether, volatile oil or various fatty oils, slightly soluble in ethanol. It has stable chemical properties and does not react with acids, alkalis, oxidants and reducing agents. It will turn yellow under ultraviolet irradiation, can burn and decompose, and is stable at room temperature.
There are three main performance indicators of paraffin wax, namely melting point, oil content and stability. Let’s take a look at them below:
Melting point
Paraffin wax is a mixture of hydrocarbons, so it does not have a strict melting point like pure compounds. The so-called melting point of paraffin refers to the temperature at which a stagnation period first appears on the cooling curve when the paraffin sample is cooled and melted under specified conditions. Various wax products require paraffin wax to have good temperature resistance, that is, it will not melt or soften and deform at a specific temperature. Commercial paraffin wax is required to have a series of different melting points depending on the conditions of use, the region and season of use, and the use environment.
The main factor that affects the melting point of paraffin is the weight of the raw material fraction selected. The paraffin wax extracted from the heavier fraction has a higher melting point. In addition, the oil content also has a great influence on the melting point of paraffin wax. The more oil contained in paraffin wax, the lower its melting point.
Oil content
Oil content refers to the amount of low melting point hydrocarbons contained in paraffin wax. Excessive oil content will affect the color and storage stability of paraffin, and will also reduce its hardness. Therefore, the wax-containing paste extracted from the vacuum fraction needs to be deoiled by sweating or solvent methods to reduce its oil content. However, most paraffin products need to contain a small amount of oil, which is beneficial to improving the gloss and release performance of the product.
Stability
During the modeling or coating process, paraffin wax products are in a hot melt state for a long time and are in contact with the air. The stability is not good when added. It is easy to oxidize and deteriorate, become darker in color, and even emit a smell. In addition, paraffin wax will turn yellow when exposed to light during use. Therefore, paraffin wax is required to have good thermal stability, oxidation stability and light stability.
The main factor affecting the stability of paraffin wax is the trace amounts of non-hydrocarbon compounds and condensed aromatic hydrocarbons it contains. In order to improve the stability of paraffin wax, it is necessary to deeply refine the paraffin wax to remove these impurities.
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