| 摘要 |
In the process and a correspondingly appropriate device for preparing homo- or copolymers of at least one of the polymerizable monomers of the group consisting of styrene, butadiene, vinyl chloride, vinyl acetate, vinylidene chloride, alkyl (meth)acrylate (meth)acrylic acid, (meth)acrylonitrile and (meth)acrylamide reaction is carried out at at least 40.degree.C in the presence of a dispensing auxillary and of a free-radical polymerization initiator such that at least 85 % by weight of the polymer is formed from these monomers. In the multistage process the procedure is such that a) in a first stage water is added as a solvent which is inert in the reaction, and dispensing auxiliaries, seed and a first portion of monomer(s) are added if desired, b) in a second stage initiator is added, and c) in a third stage the remainder or all of the monomer(s) is added directly or in emulsion form and in the presence of further water and, if desired, further dispersing auxiliary or other auxiliaries. it also being possible to operate any two of the stages as a single stage. The reaction mixture, which is in emulsion from, is moved in all or some stages through an external circuit which leads from and back to the reaction vessel (2) and comprises at least one low-shear pump (7) and at lest on heat exchanger (8) having an essentially laminar flow profile. The products prepared by this process, which involves short preparation times, have good performance properties (for adhesive bonds, for example).
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