Identifying plastics?

My first thought was UHMW but you say not slippery.
Then I thought Acetal, but maybe not, though that doesn't really feel slippery to me.
Delrin? Then I saw the glass filled.
If it is ballistic I am back to UHMW, but it doesn't float....

Scrap-binium!

Can you take a chip from it with a razor or a drill?
Does it abrade with some 60 grit?
 
Let me clarify. I am not at all sure it is glass filled. I was just thinking of why it might seem so dense. I can calculate its density if needed.

It is not acetal or polyethylene since it does not burn. It turns fine and can be cut with a box cutter. It abrades easily.

Allegany Ballistics mostly made rocket motors for NASA and the military so this was not necessarily used in a projectile. In fact one of their big items was kevlar wound tubes for motor casings.

Based on the table I posted this could also fit with Polyimide (Vespel). I don't think that is commonly white. Kevlar is also not white.

Very interesting detective work here.
 
I used the displacement method to get the volume of 110cm3 the mass is 230g. The calculated density is therefore 2.1 g/cm3

Based on this list: https://omnexus.specialchem.com/polymer-properties/properties/density#values
There are only a few possibilities assuming it is not glass filled and otherwise homogeneous.

PTFE
FEP (Dyneon)
PCTFE
PFA (Dyneon also?)

How can I tell if this is glass filled? Would microscopic examination see that?
 
There aren't too many plastics that don't burn. Teflon is one. PEEK is self extinguishing. Polyimide apparently is also self extinguishing.
 
We used a glass filled PP for one of our products. It had a texture that felt gritty when cut.
 
I don't think PEEK and Polyimide are dense enough to fit? This material does feel slightly gritty on the cut edge. I wish I had a microscope handy.
 
Many (too many) years ago I purchased a number of plastic rods for my daughter's science project (differences in static charge developed by different materials – I don't think the teacher liked it because one of the materials was rabbit fur). I keep these separate from my other rod stock so I can make an educated guess on unknown materials.
 
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Light microscopy up to 500X (admittedly using a cheap digital microscope) is unrevealing. I guess I was hoping to see reflective glass fibers...
Here is a pic:
1669739476832.png


The small washer at the top is known PTFE. The other plastic is a slightly grayer hue. It also feels much stiffer.
Given these differences I am leaning towards glass filled PTFE. Comments invited.

Apparently I could test its solubility in Perfluoro kerosene at 350deg C. Simple enough...
 
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I measured the density of a bar of PEEK and got 1.30 g/cc. PEEK also has a tan, sort of flesh colored, color in its natural state so it would not be white.
 
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Nice. That is right in line with the chart I found. I agree we can exclude PEEK.
I should note that if this is glass filled PTFE it costs $143/ft at McMaster!
 
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