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采用分子动力学（ＭＤ）模拟方法研究了真空状态下单链聚乙烯从伸直链开始的结晶过程。结果表明，整个模拟过程可以分成３个阶段。由于内聚能和熵的驱动，伸直链开始因各个σ键的内旋转和构象态跃迁而卷曲、聚集，渐渐形成具有一定密度的无规线团，这一阶段称为“内聚阶段”。从无规线团开始，通过分子链段的调整而形成结构比较规整的片晶（Ｌａｍｅｌａ）结构，是“有序化阶段”。该阶段可用通常处理结晶实验数据的Ａｖｒａｍｉ方程描述（在３００Ｋ，ｎ＝１４４，Ｋ＝４９２×１０－４ｓ－１４４），属于无热成核、受链段扩散控制的三维生长的结晶生长机制。在最后的“调整阶段”，模拟体系的能量和有序度基本稳定，但片晶的形状还在做动态调整。模拟过程的３个阶段与聚合物本体结晶过程中结晶成核、晶体生长和晶体完善不同但有相似之处。
The molecular dynamics (MD) simulation method was used to study the crystallization process of single chain polyethylene under the condition of vacuum. The results show that the entire simulation process can be divided into three stages. Due to the cohesion energy and entropy, the straightening chain starts to curl and aggregate due to the internal rotation and the conformational transition of each σ bond, and gradually form a random coil with a certain density. This phase is called “cohesive phase” . From the beginning of the random coil, through the adjustment of the molecular chain to form a regular structured Lamela structure, it is the “ordering stage.” This phase can be described by the Avrami equation, which usually deals with crystallographic data (at 300K, n = 144, K = 492 × 10-4s-144), belonging to the three-dimensional Growth of the crystal growth mechanism. In the final “adjustment phase”, the energy and order of the simulation system are basically stable, but the shape of the lamellae is still undergoing dynamic adjustment. The three stages of the simulation process are similar to the crystallization nucleation and crystallization and crystal refinement of the polymer bulk.