|Trexel, Inc. Patent applications|
|Patent application number||Title||Published|
|20120177766||BLOWING AGENT INTRODUCTION SYSTEMS AND METHODS - The present invention provides blowing agent introduction systems and methods for introducing blowing agent into polymeric foam processing systems. The methods may involve introducing one or more doses of blowing agent into polymeric material in an extruder during a plastication period of a molding cycle. Prior to introduction, a dose is confined in an accumulator which, for example, has a volume defined between an inlet valve and an outlet valve. A control system may receive inputs related to system parameters (e.g., pressure of polymeric material in extruder, axial position of screw in barrel, whether screw is rotating, and the like) and based on the inputs coordinates operation of the valves to confine and introduce the blowing agent dose(s). The introduction systems may be used in discontinuous plasticating processes, such as injection molding and blow molding, and can be particularly useful in processes that use precise quantities of blowing agent.||07-12-2012|
|20100086636||POLYMER PROCESSING SYSTEMS INCLUDING SCREWS - Injection molding and blow molding systems that include screws having low L:D ratios are provided. The systems are capable of producing microcellular polymeric materials. In some cases, the systems may be formed by retrofitting conventional polymer processing systems. Retrofitting may involve changing (e.g., machining or replacing) existing components of the conventional system, as well as, adding new components to the system. For example, retrofitting generally involves replacing the conventional polymer processing screw with a new screw designed to satisfy conditions needed for processing microcellular materials. In other cases, the systems may be newly manufactured. The retrofitted or newly manufactured systems of the invention are considerably less expensive than newly manufactured microcellular processing systems having higher L:D ratios.||04-08-2010|
|20080226892||FIBER-FILLED MOLDED ARTICLES - Polymer molding processes, such as injection-molding processes, include use of a viscosity-reducing supercritical fluid additive resulting in less breakage of reinforcing fibers upon introduction into the mold.||09-18-2008|
Patent applications by Trexel, Inc.