Texture powder: What is this black magic?

I just inherited some kind of cool stuff called Osis Dust-it Texture Power from a friend who started cowashing and gave away most of her styling products.  I assumed it was dry shampoo by another name, but once it’s on the hair it gets a kind of unusual tacky consistency and puffs everything up; the effect is visually similar to backcombing.  The packaging says the effect is coming from silica silylate, which I’m not familiar with and haven’t been able to find much about.  Just wondering what it is that activates the powder (it stays powdery in my hand, so I guess it’s not skin or heat but something particular about hair?), why that type of stickiness would create volume rather than weighing everything down (which is my usual experience with, say, gel or hair wax), and if there’s any potential for it to be damaging?