Rastogi Sanjay, Yao Yefeng, Lippits Dirk R, Höhne Günther W H, Graf Robert, Spiess Hans Wolfgang, Lemstra Piet J
Department of Materials, Loughborough University, Leicestershire LE11 3TU, United Kingdom; Department of Chemical Engineering and Chemistry/ The Dutch Polymer Institute, Eindhoven University of Technology, P.O. Box 513; 5600MB Eindhoven, The Netherlands; Max-Planck-Institute for Polymers, Ackermannweg 10, 55128 Mainz, Germany.
Macromol Rapid Commun. 2009 May 19;30(9-10):826-39. doi: 10.1002/marc.200900025. Epub 2009 May 13.
Detailed knowledge on chain mobility in polymers is of fundamental interest in order to understand their mechanical properties. As a specific example, the melting behavior of semicrystalline polyethylene can be studied by thermal analysis and NMR spectroscopy. In ultra high molecular weight polyethylene (UHMW-PE) crystallised via different routes, i.e., directly during polymerisation, from solution, or from the melt, and melted under different protocols, different melting processes involving detachment of stems from the crystals and cluster melting can be distinguished. Melting by the consecutive detachment of chain stems from the crystal substrate ultimately results in a melt state where chain dynamics for entanglement formation are much more restricted.
为了理解聚合物的力学性能，深入了解聚合物中链的流动性具有重要的基础意义。作为一个具体例子，可以通过热分析和核磁共振光谱研究半结晶聚乙烯的熔融行为。在通过不同途径结晶的超高分子量聚乙烯（UHMW-PE）中，即在聚合过程中直接结晶、从溶液中结晶或从熔体中结晶，并在不同条件下熔融，可以区分出不同的熔融过程，包括链段从晶体上脱离以及簇状熔融。链段从晶体基质上依次脱离导致最终的熔融状态，其中形成缠结的链动力学受到更大限制。
