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I. Dynamics of block copolymer nanostructures. II. Polymerizability of cyclic olefins and ring-closing metathesis.

机译：I.嵌段共聚物纳米结构的动力学。二。环烯烃的可聚合性和闭环易位。

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Self-assembly of block copolymers provide versatile means to create nanostructures with potential applications in nanotechnologies. The form and size of these structures are controlled by the type and the length of each block, and the number of blocks. Active processing using symmetry-breaking fields such as flow can extend self-assembled order into the macroscopic dimensions, thus gain desired directional properties, such as transport, optical, and electrical properties. Towards the integrated synthesis and processing of functional block copolymer nanostructures, the dynamics of flow-induced alignment of block copolymers provide the basis to predict the direction, rate, and degree of alignment, while defect dynamics and thermodynamics give insight into the possibilities of formation of desired nanostructures. Using an integrated experimental approach, which combines in-situ rheo-optical measurements and ex-situ structural characterization by electron microscopy and x-ray scattering, three different alignment trajectories are investigated: perpendicular alignment and two qualitatively different routes to parallel alignment. It is a cascade of dynamics responses of chains, nanophases, and domains during oscillatory shear that determines the alignment regimes. At the highest frequencies, chain distortion and symmetry arguments explain the transient development of a bimodal texture en route to alignment of layers parallel to the planes of shear. At lower frequencies, larger scale relaxations introduce rearrangements out of the deformation plane that permit formation of lamellae perpendicular to the shear plane. For each trajectory in general, the initial 'fast' process enhances projections of a certain range of distributions; the late-stage 'slow' process eliminates other projections and perfects a single alignment. ABC triblock copolymer can form a fascinating array of nanostructures: dramatic changes of morphology and alignment behavior are induced simply by switching the permutation of the blocks, molecular size, shear condition, and temperature. Both thermotropic and shear-induced phase transitions, and new types of defects are observed.; Olefin metathesis by transition metal complex has been a powerful method in polymer and organic synthesis. A model is developed to predict the ring-chain equilibria in ring-opening-closing reaction. Predictions on the polymerizability of cyclic olefins agree well with experiments. We have extended this model to assist ring-closing metathesis of eight-member rings, which can be a useful starting material for drug synthesis.
机译：嵌段共聚物的自组装提供了创建具有纳米技术潜在应用潜力的纳米结构的通用方法。这些结构的形式和大小由每个块的类型和长度以及块的数量控制。使用打破对称性的字段（例如流）进行主动处理可以将自组装顺序扩展到宏观维度，从而获得所需的方向特性，例如传输，光学和电特性。对于功能性嵌段共聚物纳米结构的集成合成和加工，嵌段共聚物的流致取向排列动力学为预测方向，速率和排列程度提供了基础，而缺陷动力学和热力学则提供了对形成嵌段共聚物的可能性的认识。所需的纳米结构。使用集成的实验方法，结合了原位流变光学测量和电子显微镜和X射线散射的异位结构表征，研究了三种不同的对准轨迹：垂直对准和两条在质量上不同的平行对准路线。它是振荡剪切过程中链，纳米相和畴的动力学响应的级联，确定了排列方式。在最高频率下，链畸变和对称性参数解释了双峰织构在过渡到平行于剪切平面的层的过程中的瞬时发展。在较低的频率下，较大比例的松弛会在变形平面之外引入重排，从而允许垂直于剪切平面形成薄片。通常，对于每个轨迹，初始的“快速”过程都会增强对特定范围分布的预测；后期的“慢速”过程消除了其他预测并完善了单个对齐方式。 ABC三嵌段共聚物可以形成令人着迷的纳米结构阵列：只需切换嵌段的排列，分子大小，剪切条件和温度，即可引发形态和排列行为的显着变化。热致和剪切诱导的相变，以及新的缺陷类型都可以观察到。过渡金属络合物进行烯烃复分解一直是聚合物和有机合成中的有效方法。建立了预测开环-闭环反应中的环链平衡的模型。关于环烯烃的可聚合性的预测与实验非常吻合。我们扩展了该模型，以协助八元环的闭环易位，这可能是药物合成的有用起始材料。

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