Why talc is soft and slippery

Talcum powder absorbs water, which makes it perfect for sweaty athletes who want to keep a good grip. Join Tigtag today to view this video Explore thousands of award-winning elementary resources. Start free trial or subscribe Already a subscriber? Talc in sport Time: Share. Explore more resources. This creates a physical barrier to the transmission of moisture, thereby improving water and humidity resistance.

This impermeability can aid, however, in the formation of blisters as any moisture or gases leave the substrate. Platy talc reinforces the dry coating film because of its alignment therein and its naturally high aspect ratio. This reinforcement makes the film more resistant to cracking or rupture in response to stretching and flexing, thus better insulating the substrate from the environment. The combination of barrier properties, alkaline pH and reinforcement accounts for talc's contribution to corrosion inhibition.

Its barrier properties also make platy talc well-suited for primers and sanding sealers used on porous substrates to control penetration. In exterior paints, platy talcs tend to chalk more readily than most extender pigments, although less than calcium carbonate. In liquid coatings, mesh or 4 Hegman talcs are most commonly used. The micronized talcs, 6 Hegman or finer, are used for TiO2 extension, good low angle sheen and good burnishing resistance.

Macrocrystalline varieties are preferred for their excellent flatting. Tremolitic talc often provides better film reinforcement, but somewhat greater permeability than platy talc. Barrier properties are generally not as good, however this reduces the tendency to blister.

For corrosion control, greater permeability is compensated for by greater alkalinity in addition to film durability. In epoxy marine primers, tremolitic talc is preferred for greater corrosion resistance with less blistering. Tremolitic talcs with 4 Hegman fineness are the most widely used grades in architectural, industrial and marine coatings. For more information on talc, contact RT Vanderbilt Co. This is why it is used in many industries as a lubricant and for anti-stick properties.

For example, it is used to stop sheets of rubber from sticking to each other, and by gymnasts to keep their hands dry. In the building industry it can be used for reinforcement and as an electric and heat insulator. Talc is popular as a filler to cheapen various other items such as bars of toilet soap. Talc and asbestos Talc has had some bad press because there are some talc deposits that contain asbestos.

Here are some tips: If the price is much cheaper than other talcs, that could be a clue. Check the data sheet for the CaO content. Pour some vinegar on a small sample. If it fizzes, then you have calcite in your talc!

Would you like to see a paint formulation which contains no TiO2? Naturally, this substance is hydrophobic dislikes water , and tends not to absorb water, therefore giving some of its favourable water-resistant characteristics.

Both of these minerals are nearly identical, each being very soft. Both can be easily crushed and cut, because they are so soft.

Also both have perfect cleavage in one direction, allowing these minerals to break into thin sheets. Each feels greasy to the touch, this is why talc is used for a lubricant, and both are formed in metamorphic environments. Madoc, Ontario. Some replacements for talc when manufacturing ceramics are clays and pyrophyllite. Kaolin and mica can be substituted instead of talc in rubber paint and plastics production. For paper production, kaolin can be used in place of talc.

There is an abundance of talc with sufficient amounts for many decades to come, but some of these alternatives may be cost-effective depending on the cost of talc. Talc was first discovered on a farm in Madoc in the s. It was that the Henderson Talc Mine came into production. In the Conley Mine opened in the adjacent property, where there contained a northeast extension of the Henderson ore body.