1 сентября, 2015 
Malyar A Loop continuous reactor uses a broadly similar formulation to the batch case, but the poly(vinyl alcohol)-containing solution is pumped in continuously rather than added to the reactor initially. Also, a redox initiator is used:
Parts by weight (kg)
1. Initial reactor filling
Process water 46.3
Poly(vinyl alcohol) (88% hydrolyzed) 2.2
Poly(vinyl alcohol) (98% hydrolyzed) 1.3
Sodium acetate 0.1
Sodium metabisulfite 0.1
50.0
2. Water/stabilizer feed
Process water 489.6
Poly(vinyl alcohol) (88% hydrolyzed) 23.6
Poly(vinyl alcohol) (98% hydrolyzed) 14.1
Sodium acetate 1.1
Sodium metabisulfite 1.0
3. Monomer feed
Vinyl acetate 419.2
4. Initiator feed
t-Butyl hydroperoxide 1.1
5. Plasticizer
Dibutyl phthalate 50.0
6. Preservative/antifoam
Preservative 0.2
Antifoam 0.1
1000.0
Process: Pump into the Loop reactor the initial fill. Start the circulation pump. Start to pump the water-stabilizer solution, followed by the monomer feed and the initiator, to give a total feed of raw materials of 500kg/h. Allow the temperature to rise to 55°C and apply cooling to stabilize the temperature to 55 ± 1°C. Collect the product and add dibutyl phthalate after holding the completed required volume for 20 min at about 50°C. Cool and add the preservative and antifoam at 35°C or less.
B. Vinyl Acetate-Ethylene Copolymers
1. Batch Reactor Process
The following formulation illustrates the use of a redox initiator in a batch process. Also, the introduction of N-methylol acrylamide increases the molecular weight and chain cross-linking, minimizing the thermoplastic properties of the adhesive and the tendency to cold flow.
Parts by weight (kg)
1. Initial reactor charge
Deionized water 380.0
Poly(vinyl alcohol) (88% hydrolyzed) 25.0
Sodium bicarbonate 2.0
Ammonium persulfate 5.0
2. Initial monomer charge
Vinyl acetate 50.0
Ethylene (to 250 psi)
3. Reducing initiator
Sodium formaldehyde sulfoxylate 1.5
Deionized water 25.0
4. Continuous monomer feed (1)
Vinyl acetate 446.0
5. Continuous monomer feed (2)
N-Methylol acrylamide 4.5
Deionized water 60.0
6. Preservative, etc.
Preservative 0.5
Antifoam 0.5
1000.0[15]
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