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Epoxy Resin
Woody

Imeundwa na

Woody

22. Septemba 2026NO
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Epoxy Resin

Pierre Castan, a Swiss chemist at the dental firm De Trey Frères, was looking for a resin for dentures. He reacted a phenol carrying two hydroxy groups with epichlorohydrin, then hardened the product with an acid anhydride, and got a hard, clear, unusually adherent solid. Ciba licensed it and sold it as Araldite; in the US Sylvan Greenlee developed epoxies independently. **US 2,324,483**, "Process of preparing synthetic resins", Castan, granted 20. July 1943, claims condensing "a polybasic carboxylic acid anhydride" with the product of "a phenol having at least two phenolic hydroxy groups and of an epichlorhydrine". It does not single out bisphenol A, the phenol most epoxies use today. **Epichlorohydrin is a carcinogen; you start from a two-part kit.** You glue pine lap joints at the right ratio and four wrong ones, then test hardness and break the joints.
Mwanzo
2 hours plus 24 h cure

Maagizo

1

Cut the joint pieces

Saw ten pine strips 100 x 25 mm. Sand one face of each end with 120 grit and dust off. Label five pairs 1:1, 1.25:1, 1:1.25, 1.5:1 and 1:1.5.

Vifaa kwa hatua hii:

Ubao wa msonobariUbao wa msonobari1 kipande
Sandarusi (karatasi ya kusugua)Sandarusi (karatasi ya kusugua)1 karatasi
Utepe wa kufunikaUtepe wa kufunika1 rolii

Zana zinazohitajika:

Msumeno wa mkonoMsumeno wa mkono
Rula ya chumaRula ya chuma
PenseliPenseli
2

Measure by syringe

Gloves on. For each ratio draw resin and hardener in separate syringes (1:1 = 2 ml + 2 ml; 1.25:1 = 2.5 + 2; and so on) into its own cup. This assumes a 1:1-by-volume kit - scale to your label.

Vifaa kwa hatua hii:

Epoksi ya Sehemu MbiliEpoksi ya Sehemu Mbili25 ml

Zana zinazohitajika:

Glavu za NaitriliGlavu za Naitrili
Seti ya sindano za kunyonyaSeti ya sindano za kunyonya
Vikombe vya kuchanganya vilivyodarajwaVikombe vya kuchanganya vilivyodarajwa
Miwani ya usalama iliyo waziMiwani ya usalama iliyo wazi
3

Mix thoroughly

Stir each cup 2 minutes, scraping the walls and bottom. Unmixed streaks behave like a wrong ratio.

Zana zinazohitajika:

Fimbo ya KukorogaFimbo ya Kukoroga
4

Glue and pour

Spread each mix on the sanded ends of its pair, overlap them 25 mm and spring-clamp over wax paper. Pour the rest as a coin-sized puddle on wax paper beside it.

Vifaa kwa hatua hii:

Karatasi yenye ntaKaratasi yenye nta1 karatasi

Zana zinazohitajika:

Kibanio cha springiKibanio cha springi
5

Cure 24 hours

Leave everything at room temperature, 20 °C or warmer, for 24 hours. Cold slows the cure.
6

Pencil hardness

Sharpen pencils 6B to 6H and flatten the tips on 400 grit. Push each at 45° across a puddle, from hard down, until one no longer scratches. Record that grade.

Zana zinazohitajika:

Seti ya penseli za grafitiSeti ya penseli za grafiti
Lupu ya KukuzaLupu ya Kukuza
7

Break the joints

Clamp one strip of a joint in the vise and tap the free end sideways with the mallet until it breaks. Estimate how much of the bond face is torn wood.

Zana zinazohitajika:

Kibano cha meza ya kaziKibano cha meza ya kazi
Nyundo ya mpiraNyundo ya mpira
Miwani ya usalama iliyo waziMiwani ya usalama iliyo wazi
8

Ratio, leftovers, results

Inapakia daftari la Jupyter…
9

History & Context

**What the patent specifies:** a resin from a two-hydroxy phenol and epichlorohydrin, hardened by a polybasic acid anhydride. **Modern build (derived):** a two-part kit, most with an amine hardener that cures at room temperature. Epoxy became the glue that holds metal, the matrix of fibreglass and carbon-fibre parts, and the boat-builder's resin. Its limits: it yellows in sunlight, softens with heat, and uncured resin and hardener sensitise skin - which is why the gloves stay on every time.

Vifaa

5

Zana Zinazohitajika

13

Blueprint zinazohusiana

Blueprint hizi zinashiriki maarifa — mbinu, vifaa au kanuni

Making Bakelite — The First Fully Synthetic Plastic That Launched the Age of Polymers
Hatari

Making Bakelite — The First Fully Synthetic Plastic That Launched the Age of Polymers

na CharlieDE

Viwandani

49
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1
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Casting Clear Epoxy Resin Paperweights — Embedding Objects in Resin

Casting Clear Epoxy Resin Paperweights — Embedding Objects in Resin

na MaryFI

Kemia

70
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0
0
0
0
Silicone (Rochow Direct Process)

Silicone (Rochow Direct Process)

na ClayDK

Utengenezaji wa Plastiki

1
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0
0
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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.

Majadiliano

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