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UBUKORIKORI
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IMYIDAGADURO
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IBYAMBARWA
Polycarbonate
In 1953 Hermann Schnell at Bayer joined bisphenol A into long chains through carbonate links and got a clear plastic of remarkable toughness. Daniel Fox at General Electric reached the same material independently the same year, and both companies were selling it by around 1960.
**US 3,028,365**, "Thermoplastic aromatic polycarbonates and their manufacture", Schnell, Bottenbruch and Krimm, assigned to Bayer, filed 12. October 1954, granted 3. April 1962, claims "a high molecular weight, thermoplastic polycarbonate having a melting point of at least about 135°C", made from bisphenol A among a wider family.
**The classic route uses phosgene, a war gas.** You build a drop-weight rig and find the energy that cracks acrylic - then drop the same on polycarbonate.
Utangiye
2 hours
Amabwiriza
1
1
The specimen table
The specimen table
Cut a 300 x 300 mm plywood board and bore a 100 mm hole in its centre with the hole saw. Rest it on two blocks so the hole is open underneath.
Ibikoresho by'iyi ntambwe:
Urupapuro rw'ibiti byometse1 igiceIbikoresho bikenewe:
Umucumita w'Intoki
Ibyuma byo gucamo utwenge
Icyuma Cyivumbura Kidafite Insinga2
2
The drop tube
The drop tube
Take 2 m of 32 mm PVC pipe. Mark heights from the bottom every 100 mm and drill a 3 mm hole straight through at each mark. A nail through a hole holds the ball; pulling it drops the ball from that height.
Ibikoresho by'iyi ntambwe:
Umuyoboro wa PVC2 metero
Imisumari1 igiceIbikoresho bikenewe:
Umugozi wo Gupima
Igikoresho cy'ikaramu z'irangiIcyuma Cyivumbura Kidafite Insinga
Ibikoresho by'ibivumbura mu gasanduku3
3
Stand it plumb
Stand it plumb
Clamp the tube to a post or bench leg with pipe clamps, its bottom 10 mm above the hole's centre. Check it with the plumb bob in two directions.
Ibikoresho bikenewe:
Ipfundo ry'umuyoboro
Igipimo cyo kugororoka4
4
Clamp a sheet
Clamp a sheet
Cut 150 x 150 mm squares of 3 mm acrylic and 3 mm polycarbonate. Leave the protective film on. Clamp one over the hole at all four corners.
Ibikoresho by'iyi ntambwe:
Urupapuro rwa Akiriliki1 igice
Urubaho rwa polikaribonate (rubonerana)1 igiceIbikoresho bikenewe:
Igifata gifite ishusho ya C
Amadarubindi Asobanutse yo Kwirinda5
5
Climb the ladder
Climb the ladder
Glasses on. Weigh the 25 mm ball. Drop it from 100 mm, then 200 mm, and so on, on a fresh spot each time, until the acrylic cracks. Record that height. If it survives the top hole, repeat with the 1 kg weight as in the next step.
Ibikoresho bikenewe:
Igikoresho cy'utubumbe tw'icyuma
Iminzani ya Digitale NyayoAmadarubindi Asobanutse yo Kwirinda6
6
Same on polycarbonate
Same on polycarbonate
Repeat the whole ladder on polycarbonate. If it survives the top hole, tape the 1 kg weight to a rounded bolt head and drop that from 1.8 m outside the tube, hands clear.
Ibikoresho bikenewe:
UburemereAmadarubindi Asobanutse yo Kwirinda7
7
Energy at failure
Energy at failure
Gupakira ikaye ya Jupyter…
8
8
History & Context
History & Context
**What the patent specifies:** high-molecular aromatic polycarbonates from dihydroxy compounds such as bisphenol A, melting at 135 °C or more. **Modern build (derived):** extruded clear polycarbonate sheet.
It went into safety glasses, riot shields, machine guards, bottles and later CDs. Its limits: it scratches easily, yellows in sunlight without a UV coat, is attacked by some solvents, and bisphenol A leaching from food containers made many makers switch those to other plastics.
Ibikoresho
5- 1 igiceUmwanya
- 2 meteroUmwanya
- 1 igiceUmwanya
- 1 igiceUmwanya
- Umwanya
Ibikoresho bikenewe
13- Umwanya
- Umwanya
- 1 vendor sell this, none ship to you yetUmwanya
- 1 vendor sell this, none ship to you yetUmwanya
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Blueprint zijyanye
Izi blueprint zisangira ubumenyi — uburyo, ibikoresho cyangwa amahame
CC0 Umurenge rusange
Iyi blueprint yasohowe munsi ya CC0. Ushobora gukoporora, guhindura, gukwirakwiza no gukoresha nta kwemererwa.
Shyigikira Umuremyi ugura ibicuruzwa binyuze muri Blueprint ye Komisiyo y'Umuremyi byashyizweho n'Abacuruzi, cyangwa kora verisiyo nshya y'iyi Blueprint ukayinjiza nk'isano muri Blueprint yawe kugira ngo musangire inyungu.