| 摘要 |
The invention relates to a process for the preparation of polymers stabilized with protective colloids in the form of water-redispersible powders or aqueous dispersions thereof having a reduced content of volatile components, bya) polymerizing by emulsion or suspension polymerization, one or more monomers from the group consisting of vinyl esters, (meth)acrylates, vinyl aromatics, olefins, 1,3-dienes and vinyl halides and optionally further monomers copolymerizable therewith,b) aftertreating the polymer dispersion thus obtained by means of postpolymerization, distillation, and/or introduction of steam or inert gas to obtain a residual content of volatile, nonaqueous components of <2000 PPM, ANDc) spray drying of aftertreated polymer dispersion to a residual content of volatile, nonaqueous components of <400 ppm, the dispersion being adjusted prior to spray drying to a solids content of <45% by weight before spraying, the spray drying performed with gas at an inlet temperature of >120° C., and optimallyd) redispersing of the resulting powder in water.
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