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TEKNOLOGI
BOLEH PAKAI

PVA Wood Glue by Emulsion Polymerisation
White wood glue is polyvinyl acetate (PVAc) dispersed in water. It is made by emulsion polymerisation: vinyl acetate monomer is stirred into water with a stabiliser, here polyvinyl alcohol, and a water-soluble initiator such as a persulfate, which splits into radicals above about 50 °C and starts chains that link the monomer into polymer. The water carries away the heat, so the reaction stays under control. More monomer is usually fed in slowly as the particles grow. What comes out is a milky dispersion, and for glue that dispersion is the product. Vinyl acetate itself is made from ethylene, acetic acid and oxygen over a palladium catalyst.
Lanjutan
Hours per batch (industrial)
Arahan
1
1
Charge the reactor
Charge the reactor
Fill the jacketed reactor with water and dissolve the polyvinyl alcohol, which keeps the polymer particles from clumping.
Bahan untuk langkah ini:
Air Suling1 as required
Serbuk polivinil alkohol1 as requiredAlatan diperlukan:
Reaktor pempolimeran berjaket2
2
Heat and start
Heat and start
Warm the water to above about 50 °C, add part of the monomer and the persulfate initiator; the initiator splits into radicals and polymerisation begins.
Bahan untuk langkah ini:
Monomer vinil asetat1 as required
Pemula persulfat1 as requiredAlatan diperlukan:
Reaktor pempolimeran berjaket3
3
Feed and hold
Feed and hold
Feed the rest of the monomer in slowly while stirring; the jacket removes the heat of reaction so the temperature stays steady.
Alatan diperlukan:
Reaktor pempolimeran berjaket4
4
Finish
Finish
When the monomer is used up, cool the milky dispersion. It is used as it is: as wood glue, white or yellow carpenter's glue.
Alatan diperlukan:
Reaktor pempolimeran berjaketBahan
4- 1 as requiredPemegang Tempat
- 1 as requiredPemegang Tempat
- 1 as requiredPemegang Tempat
- 1 as requiredPemegang Tempat
Blueprint ini membuat
Blueprint berkaitan
Blueprint ini berkongsi pengetahuan — teknik, bahan atau prinsip
CC0 Domain Awam
Blueprint ini dikeluarkan di bawah CC0. Anda bebas menyalin, mengubah, mengedar, dan menggunakan karya ini untuk sebarang tujuan, tanpa meminta kebenaran.
Sokong Pembuat dengan membeli produk melalui Blueprint mereka di mana mereka memperoleh Komisen Pembuat ditetapkan oleh Penjual, atau cipta iterasi baru Blueprint ini dan sertakan ia sebagai sambungan dalam Blueprint anda sendiri untuk berkongsi hasil.



