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, by
a) 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, and
c) 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.degree. C., and optimally
d) redispersing of the resulting powder in water.
A invenção relaciona-se a um processo para a preparação dos polímeros estabilizados com os colóides protetores no formulário dos pós da água-redispersible ou das dispersões aqueous disso que têm um índice reduzido de componentes temporários, a) polimerizando pela polimerização do emulsion ou da suspensão, por um ou mais monomers dos esters consistindo do vinil do grupo, (os meth)acrylates, os compostos aromáticos do vinil, os olefins, 1,3-dienes e os halides do vinil e promovem opcionalmente os monomers copolymerizable therewith, b) aftertreating a dispersão do polímero obtida assim por meio do postpolymerization, o distillation, e/ou a introdução do vapor ou do gás inerte para obter um índice residual de componentes temporários, nonaqueous de 120.degree. C., e optimally d) redispersing do pó resultante na água.
