| 摘要 |
A process for the production of synthetic linear polymers which contain additives is described, in which the polymer and the additives, both in the fluid state, are mixed, the resulting mixture is homogenized, and the homogenized mixture is in part conveyed to apparatus which uses it to make a product and in part is recycled, the recycled amount being preferably at least 5% of the total weight of the mixture. The preferred polymers are polyamides. The additives may be of any kind, e.g. antistatics, and they may be added as such or as a master batch consisting of a polymeric base containing finely particulated solid materials such as carbon black, matting agents or pigments. An apparatus for carrying out the process is also described, which comprises means for mixing fluid polymer with fluid additive, means for homogenizing the stream of the resulting mixture flowing through the apparatus, and means for recycling part of the homogenized stream to a zone of the apparatus upstream of the homogenizing means and for conveying the remaining part to an apparatus for subsequent processing. Static mixters may be used to homogenize the aforesaid mixture. The amount of the mixture that is recycled may be varied by suitable means such as a variable delivery pump. A particular preferred device for mixing polymer with additive is also described, which comprises valve means for preventing the polymer from backing up into the additive feed conduit.
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