环状对苯二甲酸丁二酯低聚物(CBT)具有超低的熔体黏度，聚合可得聚对苯二甲酸丁二酯(PBT)，在热塑性复合材料领域具有重要意义。针对申请人前期实验观察到的CBT聚合产物多样化的结晶形态及其与力学性能等相关研究的不足，项目拟以CBT在"边聚合边结晶，先聚合后结晶，只聚合冷却时结晶"三类过程中聚合与产物结晶关系的研究为基础，以产物结晶的微观结构、演化机理的研究为桥梁，通过对工艺参数的选择，进行三类过程中结晶形态和材料力学性能的调控研究，建立三类过程中"工艺参数-形态调控-晶体演化-力学性能"之间的联系；最后，设计制备基于CBT的连续纤维增强复合材料，并通过有限元分析，研究增强纤维表面诱导结晶对力学性能的影响规律。项目的实施将为CBT边聚合边结晶的机理研究奠定基础，为PBT结晶形态学的研究提供新的途径，并为基于CBT和其它环状芳香基低聚物开环聚合的材料结构与性能关系的研究提供实验及理论依据。

Cyclic butylene terephthalate oligomers (CBT) is a new prepolymer resin for thermoplastic composites fabrication, which is characterized by "water-like" melt viscosity and can polymerize into high-molecule-weight poly(butylene terephthalate) (PBT) by ring-opening polymerization (ROP). According to the applicant's observation about multifarious crystals' morphologies of polymerized CBT (pCBT) and the related problems between crystals' morphologies and mechanical properties, firstly, the relationship between ROP of CBT and crystallization of pCBT will be systemically investigated, in this case, polymerization and crystallization can be divided into three categories: crystallization during polymerization, polymerization is followed in succession by crystallization, only polymerization but crystallizing during cooling. Moreover, the fine structure, evolution mechanism and tuning methods of different crystal morphologies in multi-level aggregation structure including nucleation, lamellae, spherulites and transcrystallization induced by reinforced fibers will be explored and discussed in depth. On the basis of the former results,the tuning methods of crystal morphologies and mechanical properties of pCBT from the above-mentioned three paths will be studied. The dependant relationships among processing parameters, morphologies tuning,crystal evolution and mechanical properties will be established. Finally, the composites reinforced by continuous fiber will be designed and prepared. Furthermore, the crystallization induced by reinforced fiber (including single fiber and fiber fabric) will be investigated by experiment and finite element analyzing and calculating.The implementation of the project will not only possibly develop the crystalline theory of crystallization during polymerization, lay a foundation for the intensive studies of crystallizaiton morphologies of PBT, widen the understanding of structure and properties based on the cyclic oligomers' ROP, but also provide basic experimental results and scientific evidences for CBT and other cyclic aryl-oligomers' materials design, composites preparation and practical application.