Here's an interesting announcement:

http://www.military.com/NewsContent/0,1331..._042104.00.html


So I wonder why this shear thickening fluid would have superior
ballistic stopping power to a fiber like Kevlar, especially in a
thinner volume? What role do the nano-particles play in this?

Also, what if this stuff gets into a wound what effects would it have?

It doesn't. Please re-read the article more carefully: It clearly states
in paragraph 5 that _kelvar fabric_ is =SOAKED= in the STF gel, to enhance
its performance.

Furthermore, nowhere in the article does it state that this STF-soaked
kevlar armor is _thinner_ than normal kevlar armor; it merely states that
this gel-like STF-soaked kevlar armor is more _flexible_ than "ordinary"
kevlar armor, which is a hard, inflexible, laminated composite material.


> What role do the nano-particles play in this?

The fact that the viscous carrier fluid is constrained to flow between
the interstices of the nano-particles, and that viscous forces will "drag"
the nano-particles with the flow, gives the fluid a highly non-linear
rate-dependent viscosity --- much like "Silly Putty" ™, which flows
like a highly viscous liquid at low strain rates, but behaves like an
elestic solid at medium strain rates (and shatters like glass at high
strain rates...).