20 июля, 2015 
Malyar 1. A solution of hydroxy ethyl cellulose is made in de-ionised water. To this solution is added the sodium dodecylbenzene sulphonate, ammonium acetate and ammonium persulphate.
2. 25% of the vinyl acetate and 16% of the methyl methacrylate are added and the reaction vessel is heated to the reflux temperature of the vinyl acetate (the reflux will occur at ca 67°C).
3. After 30 minutes reflux the remaining vinyl acetate and methyl methacrylate are added as a mixture continuously over a two hour period. The temperature is maintained at the reflux temperature of the reactants throughout this addition.
4. Once the addition is complete, the reflux temperature starts to increase as the monomer is converted into polymer, eventually reaching 90-95°C.
5. The reaction mass is held for 1 hour at 90-95°C to ensure reaction is complete then cooled to below 40° C for filtration.
pH 4.8
Non-volatile content 55 ± 1%
Viscosity at 25°C 330 cPs
Particle size 0.15 |im
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