A novel extrusion process for the production of polymer micropellets

Abstract

Traditional micropellet and powder‐based polymer processing techniques, such as powder bed fusion, compression molding, and rotational molding have shown an increased demand in polymer processing. These processes require powders and micropellets with a small particle size, narrow size distribution and defined geometry for a variety of polymer resins. Therefore, micropelletization technologies, where particles in the size range of 50–1,000 μm are generated, have been attracting growing attention over the past decade. A new technique, presented here, yields micropellets with a controlled morphology and narrow particle size distribution. In this process, a polymer melt is extruded through a capillary and is subsequently stretched with a hot airstream until flow instabilities or melt fracture cause it to break up into particles. Small changes in process conditions result in different size distributions and particle shapes, such as lenticular pellets, fibers, and strand segments. This work shows how processing parameters and different polymer materials influence the produced micropellets. Depending on the processed polymer resin and process conditions, spherical particles with sizes ranging from 50 to 1,000 μm can be produced using the novel extrusion technique. Comprehensive design of experiment and data analysis was used to establish a more detailed understanding of the micropelletization process. POLYM. ENG. SCI., 58:2264–2275, 2018. © 2018 Society of Plastics Engineers

Microstructures of encapsulates and their relations with encapsulation efficiency and controlled release of bioactive constituents: A review

“…Conventional extrusion is used for particle fabrication, while co‐extrusion is used for both core/encapsulant incorporation and particle fabrication. In the conventional extrusion process, a mixture of core and encapsulant is forced to flow through a nozzle and breaks into small particles (Schäfer, Meyer, & Osswald, 2018). The obtained particles would possess matrix microstructure (Silva et al., 2018).…”

A Holistic, Model-Predictive Process Control for Friction Stir Welding Processes Including a 1D FDM Multi-Layer Temperature Distribution Model

“…The high-density polyethylene (SPolytec GmbH, Goch, Germany) [28], is a non-polar standard plastic used in various applications, for example, as micro-granules for additive manufacturing [29,30], in injection molding [31], and for FPJ [5,32]. The thickness of the sheet material was 5 mm.…”

Rotomolding and polyethylene composites with rotomolded lignocellulosic materials: A review

“…Polymers specially manufactured in the form of pellets have already been developed for rotomolding. 69,70 The mold is then hermetically sealed using clamps or screws. 71 Stage 2.…”