Physical propertiesPetrolatum is a flammable, semi-solid mixture of hydrocarbons, having a melting-point usually ranging from a little below to a few degrees above 100°F (37°C). It is colorless, or of a pale yellow color (when not highly distilled), translucent, and devoid of taste and smell when pure. It does not oxidize on exposure to the air, and is not readily acted on by chemical reagents. It is insoluble in water. It is soluble in chloroform, benzene, carbon disulfide and oil of turpentine. There is a common misconception (resulting from the similar feel they produce when applied to human skin) that petroleum jelly and glycerol (glycerine) are physically similar. While petroleum jelly is a non-polar hydrocarbon hydrophobic (water-repelling) and insoluble in water, glycerol (not a hydrocarbon but an alcohol) is the opposite: it is so strongly hydrophilic (water-attracting) that by continuous absorption of moisture from the air, it produces the feeling of wetness on the skin, similar to the greasiness produced by petroleum jelly. The feeling is similar, but petroleum jelly repels water, and glycerine attracts it. Producers of microcrystalline wax3 and related materials often produce petrolatums. Some testing standards used by these companies are as follows:
Depending on the specific industry the petrolatum is used for, the petrolatum may be USP (United States Pharmacopeia) grade. This pertains to the processing and handling of the petrolatum so it is suitable for cosmetic and personal care applications. UsesChesebrough originally promoted Vaseline primarily as an ointment for scrapes, burns, and cuts, but physicians have shown that Vaseline has no medicinal effect or any effect on the blistering process, nor is it absorbed by the skin. Vaseline’s effectiveness in accelerating wound healing stems from its sealing effect on cuts and burns, which inhibits germs from getting into the wound and keeps the injured area supple by preventing the skin's moisture from evaporating. Vaseline brand First Aid Petroleum Jelly, or carbolated petroleum jelly, containing phenol to give the jelly additional anti-bacterial effect, has been discontinued. However, after becoming a medicine chest staple, consumers began to use Vaseline for myriad ailments and cosmetic uses, including chapped hands and lips, toenail fungus, nosebleeds, diaper rash, chest colds, and even to remove makeup or stains from furniture. Uses for pets include stopping fungi from developing on aquatic turtles' shells and keeping cats from making messes when they cough up furballs. In the first part of the twentieth century, petrolatum, either pure or as an ingredient, was also popular as a hair pomade. When used in a 50/50 mixture with pure beeswax, it makes an effective moustache wax. During World War II, a variety of petroleum jelly called dark red veterinary petroleum jelly was often included in life raft survival kits. Acting as a sunscreen, it provides almost perfect protection against ultraviolet rays. Most petroleum jelly today is consumed as an ingredient in skin lotions and cosmetics. Although petrolatum is less expensive than glycerol, the most common active lubricating ingredient in skin lotion, it is not used in expensive lotions, because it is not absorbed into the skin, resulting in a greasy feel. Petrolatum is a useful material when incorporated into candle wax formulas. The petrolatum softens the overall blend, allows the candle to incorporate additional fragrance oil, and facilitates adhesion to the sidewall of glass. Industrial grade petrolatum can be combined with other materials to make an effective rust proofing compounds. Petroleum jelly was formerly used as a way to pitch a spitball in baseball. Although the pitch was banned in 1920, pitchers sometimes throw "the spitter" surreptitiously. Petroleum jelly is used to moisten plasticine, as part of a mix of hydrocarbons including greater (paraffin wax) and lesser (mineral oil) molecular weights. Petroleum jelly is commonly used as a personal lubricant. (Not recommended due to its dissolving effect on condoms. See below.) It can also be used to lubricate a Rubik's Cube (if silicone spray is not available), which allows it to turn with greater ease. It can also be used to lubricate the anus if the patient is suffering from conditions like hemorrhoids or anal fissures. The purpose of this is to allow the stool to pass through the rectum easier and more freely in an effort to minimize any further damage to the tissue. It can also be used to lubricate the anus before taking rectal temperature. It can be used as a softener for cuticles and lips. Use in "Green" applicationsProducers of personal care and cosmetic products have continued to focus incorporating into their formulas materials that are based off renewable resources. To keep the desirable properties of the petroleum based petrolatum, "hybrid petrolatums" are now being used in many applications. Hybrid petrolatum utilizes a complex mixture of vegetable oils and waxes and combines them with petroleum, micro wax based technologies. This allows a formulator to incorporate higher percentages of renewable resources while maintaining the beneficial properties of the petrolatum. Due to the different carbon arrangements in vegetable based oils, producers of hybrid petrolatum must appropriately blend and match the correct petroleum and vegetable based materials in order to obtain a homogeneous mixture. This ensures the hybrid petrolatum will have compatibility comparable to a full, 100% petroleum based petrolatum when used in personal care, cosmetic, and other formulas. Dangerous uses to avoidAs the substance became more common in households, it began to be used for a number of medical purposes, some of which medical science has shown to be dangerous or damaging.
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