I had the idea that I may be able to nitrate jute string and use it as cheap fuse for simple pyrotechnics. My thought was that it would contain
sufficient cellulose to hold its structure through nitration.
I made a nitration solution of 10 mls conc HNO3 and 10 mls conc H2SO4. Once it had returned to room temp I added about 400 mm of jute string. I left
it to react for about 30 minutes. I had hoped that I would then remove the string, rinse with water then boil in water. Unfortunately there was
nothing left to remove, must be way more lignin in jute than I had anticipated. Presumably the acid mix destroys the bonds between the lignols? mayko - 1-12-2019 at 08:10
I haven't tried cotton string. I agree that it would likely work well. I will try it at some point, presumably someone else has?wg48temp9 - 1-12-2019 at 16:15
I would think a gun cotton fuse would be fast and not very effective as an ignition source.
When my father made fireworks fuses he coated wool strands in a wet black power mixture that probably contained gum arabic. After dipping the wool
thread in the mixture it was pulled thru a hole and then hung up to dry. You can probably find recipes at pyro sites.
For slow fuses simply dipping cotton string or paper in a nitrate and then drying works but you need something easily ignited at the ignition end.B(a)P - 1-12-2019 at 18:16
I tried jute because I had hoped the lignin content might give it a slower burn rate.Tsjerk - 1-12-2019 at 23:18
Rule of thumb: if plant derived material is strong (jute eg.) there is a lot of lignin, if it is flexible (cotton) there is more cellulose. B(a)P - 2-12-2019 at 10:21
Ah yep, good tip thanks, makes sense.Herr Haber - 3-12-2019 at 04:10
I haven't tried cotton string. I agree that it would likely work well. I will try it at some point, presumably someone else has?
I have.
I did this years ago with simple cotton string.
- The string breaks easily after nitration
- The string leaves a lot of residue compared to NC from cotton.B(a)P - 3-12-2019 at 10:39
Was the burn rate the same as NC from cotton wool? Herr Haber - 4-12-2019 at 06:55
No. But cotton wool burns in a flash.
With cotton string it burns slow enough for you to know it wont meet expectations.
The reason si mostly that mixed acids dont penetrate well enough.
Lint is better than cotton wool which in turn is better than cotton string.
If you dont have Urbanski's books get them from the library. There's about 60 pages on the choice of cellulose alone in the NC chapter and it's pretty
interesting.
