Have to be pretty rigid and inflexible and not much stretch...or you will have a bullet cavity lined with this material and the bullet still encased in it.
Yup, I wonder how such a thin material would stop kinetic energy. All well and good stopping a 44mag in the guts or chest but the 1200 fpe has to go some where other wise massive internal injuries will kill some one just the same.
It has merits as a secondary layer though under a standard vest, flack jacket etc.
Sort of remonds me of the old samuari using silk under the armour, if a arrow made it through it would push the silk into the wound channel and all they had to do was pull on the silk to excise the arrow head.