कला
सुन्दरता र कल्याण
हस्तकला
संस्कृति र इतिहास
मनोरञ्जन
वातावरण
खाना र पेय
रिभर्स इन्जिनियरिङ
विज्ञान
खेलकुद
प्रविधि
पहिर्न मिल्ने
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.
शुरुआती
2 hours
निर्देशनहरू
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.
यस चरणका सामग्री:
प्लाइउडको पाता1 टुक्राचाहिने औजार:
हाते आरा
होल-स सेट
तारविनाको ड्रिल2
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.
यस चरणका सामग्री:
पिभिसी पाइप2 मिटर
काँटी1 टुक्राचाहिने औजार:
नाप्ने फित्ता
रङ मार्कर सेटतारविनाको ड्रिल
बाकसमा ड्रिल बिटको सेट3
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.
चाहिने औजार:
पाइप क्ल्याम्प
साहुल4
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.
यस चरणका सामग्री:
एक्रिलिक पाता1 टुक्रा
पलिकार्बोनेट पाता (पारदर्शी)1 टुक्राचाहिने औजार:
सी-आकारको क्ल्याम्प
सफा सुरक्षा चस्मा5
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.
चाहिने औजार:
फलामको बल बियरिङ
सूक्ष्म डिजिटल तराजुसफा सुरक्षा चस्मा6
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.
चाहिने औजार:
बोझसफा सुरक्षा चस्मा7
7
Energy at failure
Energy at failure
Jupyter नोटबुक लोड हुँदैछ…
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.
सामग्री
5- 1 टुक्राप्लेसहोल्डर
- 2 मिटरप्लेसहोल्डर
- 1 टुक्राप्लेसहोल्डर
- 1 टुक्राप्लेसहोल्डर
- 1 टुक्राप्लेसहोल्डर
आवश्यक उपकरणहरू
13- प्लेसहोल्डर
- प्लेसहोल्डर
- 1 vendor sell this, none ship to you yetप्लेसहोल्डर
- 1 vendor sell this, none ship to you yetप्लेसहोल्डर
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सम्बन्धित ब्लुप्रिन्ट
यी ब्लुप्रिन्टहरूले ज्ञान साझा गर्छन् — प्रविधि, सामग्री वा सिद्धान्त
CC0 सार्वजनिक डोमेन
यो ब्लुप्रिन्ट CC0 अन्तर्गत जारी गरिएको छ। तपाईं अनुमति नसोधी प्रतिलिपि, परिमार्जन, वितरण र प्रयोग गर्न सक्नुहुन्छ।
ब्लुप्रिन्ट मार्फत उत्पादनहरू किनेर सिर्जनाकर्तालाई सहयोग गर्नुहोस् सिर्जनाकर्ता कमिसन विक्रेताले तोकेको, वा यो ब्लुप्रिन्टको नयाँ संस्करण बनाउनुहोस् र आम्दानी बाँड्न आफ्नो ब्लुप्रिन्टमा जडानको रूपमा समावेश गर्नुहोस्।