中文摘要：

聚合物管主要用于流体压力输送，要求环向强度高，耐应力开裂性能好，使用寿命长。我们借鉴天然管竹子因竹纤维轴向排列使其轴向破裂易，横向破裂难的结构特点，提出形成偏离轴向的增强相结构可以显著提高聚合物管的性能，自行设计研制了新型的聚合物管旋转挤出装置，通过芯棒和口模独立可调的旋转运动与轴向速度可调的挤出／牵引运动的不同组合，形成与常规挤出不同的应力场，并通过管内外壁双冷技术调控聚合物管中温度场，从而在聚合物管中形成和定构不同层次的偏离轴向排列的增强相结构（如取向分子、串晶、原位成纤诱导形成串晶、外加纤维等），大幅度提高聚合物管的环向强度和耐应力开裂性能，如旋转挤出聚乙烯管形成偏离轴向串晶结构，使其环向拉伸强度和裂纹引发时间分别比常规挤出聚乙烯管提高78％和544％。我们还从理论上分析了旋转挤出中聚合物的流变行为，得到其流动速率数学表达式，阐明旋转挤出形成偏离轴向增强相结构的机理。旋转挤出加工为制备高性能聚合物管提供新设备、新技术、新理论。本文简要总结了我们通过旋转挤出制备高性能聚合物管的一些研究工作。

英文摘要：

Polymer pipes are widely used to transport fluids, requiring high hoop strength, excellent resistance to stress cracking and long service life. Enlightened by the topological structural feature of bamboos that the alignment of the fibers along the bamboo axial leads to easy axial cracking but difficult transverse cracking, we emphasize the reinforcing phases off the axial direction is crucial to improve the performances of the polymer pipes. Accordingly, a novel polymer pipe rotation extrusion instrument is designed and developed, where the independently adjustable mandrel and die rotary movements and the axial-speed-adjustable extrusion or traction movement are in various combination to generate the complex stress field different from that in convention extrusion. Moreover, the temperature field across the pipe can be controlled by simultaneously cooling the inner and outer walls to generate and fix the reinforcing phases off the axial direction at different levels （oriented molecule, shish-kebab crystals, in-situ forming fibers, added fibers, etc. ）, and greatly enhance the hoop strength and resistance to stress cracking of polymer pipes, for example, the novel rotation extruded PE pipes with the shish kebab crystals off the axial direction achieve 78%and 544% increase respectively in the hoop tensile strength and the crack initiation time, as compared to the conventionally extruded PE pipes. In addition, the theological behavior during rotation extrusion is theoretically analysed and the corresponding mathematical equations are concluded to reveal the formative mechanism of the reinforcing phases off the axial direction. Rotation extrusion provides a new instrumental, technical and theoretical support for polymer pipes with high performances. This paper is a brief review of our research work on the novel rotation extrusion processing to prepare polymer pipes with high performances.