*Review* **Recent Advances in Elongational Flow Dominated Polymer Processing Technologies**

**Zhongke Yuan, Xiaochuan Chen and Dingshan Yu \***

Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education and Key Laboratory of High-Performance Polymer-based Composites of Guangdong Province, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China; yuanzhk3@mail.sysu.edu.cn (Z.Y.); chenxch29@mail2.sysu.edu.cn (X.C.) **\*** Correspondence: yudings@mail.sysu.edu.cn; Tel.: +86-21-84111395

**Abstract:** The continuous development of plasticizing conveying methods and devices has been carried out to meet the needs of the polymer processing industry. As compared to the conventional shear-flow-dominated plasticizing and conveying techniques, a new method for processing polymers based on elongational flow was proposed. This new method and the related devices such as vane extruders, eccentric rotor extruders and so on, exhibited multiple advantages including shorter processing time, higher mixing effectiveness, improved product performance and better adaptability to various material systems. The development of new techniques in the field of polymer material processing has opened up a broad space for the development of new plastic products, improved product performance and reduced processing costs. In this review, recent advances concerning the processing techniques based on elongational flow are summarized, and the broad applications in polymer processing as well as some future opportunities and challenges in this vibrant area are elucidated in detail.

**Keywords:** polymer processing; elongational flow; vane extruder; eccentric rotor extruder; numerical simulation
