Microcrystalline wax specification
Against to the more familiar paraffin wax which contains mostly un-branched alkanes . microcrystalline wax contains a higher percentage of ISO paraffinic (branched) hydrocarbons . hydrocarbons Microcrystalline waxes are a type of wax produced by de-oiling petrolatum as part of the petroleum refining process. Micro crystalline waxes when produced by wax refiners are typically produced to meet a number of ASTM specifications. These include congeal point (ASTM D938), needle penetration (D1321), color (ASTM D6045), and viscosity (ASTM D445). It is characterized by the fineness of its crystals . in contrast to the larger crystal of paraffin wax.It consists of high molecular weight saturated hydrocarbons . It is generally darker, more viscous . denser, tackier than paraffin waxes, and has a higher molecular weight . and melting point . The elastic and adhesive characteristics of micro crystalline waxes are related to the non-straight chain components which they contain. Typical micro crystalline wax crystal structure is small and thin, making them more flexible than paraffin wax. It is commonly used in cosmetic formulations.Micro crystalline waxes can generally be put into two categories: “laminating” grades and “hardening” grades. The laminating grades typically have a melt point of 140-175 F (60 – 80 oc) and needle penetration of 25 or above. The hardening grades will range from about 175-200 F (80 – 93 oc), and have a needle penetration of 25 or below. Color in both grades can range from white to brown, depending on the degree of processing done at the refinery level.Microcrystalline waxes are derived from the refining of the heavy distillates from lubricant oil production. This by-product must then be de-oiled at a wax refinery. Depending on the end use and desired specification, the product may then have its odor removed and color removed (which typically starts as a brown or dark yellow). This is usually done by means of a filtration method or by hydro-treating the wax material.Micro crystalline wax is often used in industries such as the tire and rubber, candles, adhesives, corrugated board, cosmetics, castings, and a host of others. Refineries may also utilize blending facilities to combine paraffin and microcrystalline waxes. This type of activity is prevalent especially for industries such as tire and rubber.Micro crystalline waxes have considerable application in the custom making of jewelry and small sculptures. Different formulations produce waxes from those soft enough to be molded by hand to those hard enough to be carved with rotary tools.Micro crystalline waxes are excellent materials to use when modifying the crystalline properties of paraffin wax. The micro crystalline wax has significantly more branching of the carbon chains that are the backbone of paraffin wax. This is useful when some desired functional changes in the paraffin are needed, such as flexibility, higher melt point, and increased opacity. They are also used as slip agents in printing ink .
