Abstract: The present invention relates to a process for producing substantially rounded thermosetting or thermoplastic polymer particles and also to a device used therefor. The process includes forming a mixture of polymer pellets with at least one surfactant in an aqueous medium, rapidly melting the polymer pellets under plug flow and plug free heating conditions, shearing the melted pellets into the polymer particles, and rapidly cooling the polymer particles under plug free cooling conditions. Thermosetting particles can include a blend of thermosetting polymers and crosslinking agents. The device provides for plug free conditions to ensure high production rates with substantially no clogging in the polymer conveying and polymer shearing means used in the device. The plug flow conditions ensure more uniform and predictable shearing conditions, since the polymer pellets under the plug flow condition results in substantially no pellet to pellet variation in the pellet temperature.

Abstract: An apparatus for corona discharge treatment of an article, and in particular an article comprising a conductive composite, includes a first electrode, which is a rotating, high-frequency voltage electrode and a second electrode, which is preferably a translation table, disposed with respect to the high-frequency voltage electrode so as to provide a return path to ground. The translation table supports the article to be treated, and oscillates with respect to the first electrode. Since translation table supports the article to be treated, the article itself is grounded, which is important when treating conductive composite articles. An adjustment mechanism provides a constant gap between the high-frequency voltage electrode and the article, so that the voltage does not seek the article. This enhances the efficiency of the corona treatment of the article. The first electrode rotates continuously and independently of the motion of the article in order to dissipate heat from the high-frequency voltage electrode.