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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.
Mwanzo
2 hours
Maagizo
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.
Vifaa kwa hatua hii:
Bati la mbao za kubandika1 kipandeZana zinazohitajika:
Msumeno wa mkono
Seti ya misumeno ya duara
Kekee cha Betri2
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.
Vifaa kwa hatua hii:
Bomba la PVC2 mita
Misumari1 kipandeZana zinazohitajika:
Tepi ya kupimia
Seti ya kalamu za rangiKekee cha Betri
Seti ya vichimbaji kwenye sanduku3
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.
Zana zinazohitajika:
Klampu ya bomba
Timazi4
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.
Vifaa kwa hatua hii:
Bamba la Akriliki1 kipande
Bamba la polycarbonate (angavu)1 kipandeZana zinazohitajika:
Klampu ya umbo la C
Miwani ya usalama iliyo wazi5
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.
Zana zinazohitajika:
Bearing ya tufe za chuma
Mizani ya dijitali ya usahihiMiwani ya usalama iliyo wazi6
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.
Zana zinazohitajika:
UzaniMiwani ya usalama iliyo wazi7
7
Energy at failure
Energy at failure
Inapakia daftari la 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.
Vifaa
5- 1 kipandeKishikilia Nafasi
- 2 mitaKishikilia Nafasi
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- 1 kipandeKishikilia Nafasi
Zana Zinazohitajika
13- Kishikilia Nafasi
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- 1 vendor sell this, none ship to you yetKishikilia Nafasi
- 1 vendor sell this, none ship to you yetKishikilia Nafasi
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Blueprint zinazohusiana
Blueprint hizi zinashiriki maarifa — mbinu, vifaa au kanuni
CC0 Umma Wote
Mchoro huu umetolewa chini ya CC0. Uko huru kunakili, kubadilisha, kusambaza, na kutumia kazi hii kwa madhumuni yoyote, bila kuomba ruhusa.
Saidia Mtengenezaji kwa kununua bidhaa kupitia Mchoro wao ambapo wanapata Kamisheni ya Mtengenezaji iliyowekwa na Wachuuzi, au unda marudio mapya ya Mchoro huu na uiunganishe kama kiungo katika Mchoro wako kuchangia mapato.