First, let's just say I know a few things about armour. Military armour has plates in it in most cases. Most police uniform and plainclothes/consumer armour has a pocket for plates, but it is usually soft armour. And if you think that every piece of soft armour has plates in it, you obviously have not handled very much of the stuff. Emphasis on the words SOFT, ie squishy, ie flexible, ie no plate. Plates turn you into the Tinman, and are a completely different thing than talking about kevlar, spectra, or any other aramid unless you laminate it, which you wouldn't do with gloves.

Kevlar was designed to be strong, you're right. But it also happens to have very nice insulative values (even when used in a single layer; just keep in mind how thick that layer is, even if it is between wool and silk as an insulation), and is highly resistant to ignition. It is exactly what it was designed to be- synthetic silk, it's just that it has a lousy texture so it hasn't made the grand leap to being a fashion fabric.

When you read (if you do) scifi from the 50s and 60s, and they are talking about "spider armour" or something simliar, they were predicting Kevlar.

As was pointed out, Nomex's sole value is that has an extremely high tempurature resistance, but doesn't work worth squat to keep you warm. That tempurature resistance has to do with the fact that it's ignition point is very, very high (if your nomex is burning, you're burning). It has a greatly inferior insulation value and resistance to both cutting and abrasion compaired to kevlar. It has zilch in the way of reflective value without doing something like metalizing it. (Were you thinking of asbestos?)

They use nomex or nomex/kevlar blend on the outside of bunker coats becuase it doesn't want to burn, and then there is insulation between you and the nomex so you don't burn. Flight suits are made out of uninsulated nomex mainly to protect from flash burns; they don't plan on you being in the fire with one.

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