31 августа, 2015 
Malyar A. Poly(vinyl acetate) Homopolymers
1. Batch Process
A simple formulation by the batch process is as follows:
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Parts by weight (kg)
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7. Plasticizer
Dibutyl phthalate 50.0
8. Preservative
Preservative 2.2
1000.0
Process: Make a presolution of the poly(vinyl alcohol). Add to the polymerization kettle, agitate, and heat to 65°C, meanwhile adding the other ingredients of the initial reactor charge. At 65°C, add the initial vinyl acetate monomer and the first initiator. Heat cautiously to 80°C, during which time the initial vinyl acetate will polymerize (shown by the development of a blue color, a reduction or cessation of reflux, and a slight exotherm).
Start to add the continuous monomer and initiator feeds to go in over 4 h at a steady rate. Monitor temperature and reflux continuously, especially in the early stages of the reaction. Slow the feed of monomer if reflux is excessive or temperature cannot be maintained at 80 to 85°C. Ensure that the agitation is sufficient at all times to give a small vortex that blends in added monomer and condenser return smoothly but does not create foam or splashing. When feeds are complete, add final initiator and allow temperature to rise to 90 ± 2°C (heat if necessary). Hold for 20 min, then cool, adding the dibutyl phthalate at about 65°C and the preservative at 35°C or less.
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