Variable temperature WAXS, effect

As with calcimn carbonate, the colour of talc is variable, but it can sometimes be white. Its hydrophobic surface makes it readily compatible with hydrocarbon polymers such as polypropylene, and it is used to increase the stiffness and heat distortion temperature of automotive parts, being more effective in this respect than calcium carbonate. Talc lowers the impact strength of polymers, although the effect can be mitigated to some extent by a stearate coating. Wax coatings are also used, but silanes do not react with the surface of talc. 

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