| 摘要 |
The present invention is directed to a process for the production of pellets of a sterically hindered phenol antioxidant such that the pellets have a balanced hardness so as to resist abrasion during conveyance yet being readi ly dispersed in a host plastic. Such novel pellets are achieved through the use of a processing aid consisting of a solvent selected from the group consisti ng of methylene chloride, chloroform, toluene, acetone, methylethylketone, xylene, cyclohexane, styrene, methylcyclohexane and hexane having at least 1 gram of antioxidant dissolved therein per 100 grams of solvent and thereafte r using the resulting solution of solvent and antioxidant to form a paste of additional portions of the antioxidant which is thereafter extruded, pellete d, and dried. The present invention further provides a novel process for controlling the hardness of a pelleted sterically hindered phenol antioxidan t through the addition of from 0 to 80 weight percent of an alcohol of the formula ROH wherein R is an alkyl group of from 1 to 8 carbon atoms to the solvent system employed in the preparation of the processing aid and paste o f antioxidant for further processing. The hardness of the resulting pellets is inverse to the amount of alcohol employed in the system.
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