Self-Assembly and Characterization of Block Copolymer Aggregates with a Range of Potential Applications

这项工作的重点是嵌段共聚物(BC)在溶液中的自组装，产生胶束、棒状物，特别是囊泡，这些囊泡结合了相对较小的尺寸和适合装载疏水和亲水材料的空间；释放谱将被研究。其他领域包括纳米粒子(NP)的形成、它们在BC聚集体中的封装和精确定位(在催化应用中感兴趣)。 1)各种聚集体在连续多层中的逐层组装(LBL)，以产生包含相反电荷聚集层的平面纳米结构。大的囊泡也可以作为基础结构，与周围交替的相反带电的小囊泡和/或胶束层一起创建类似黑莓的多层纳米胶囊。这些结构在催化和多种成分的控制释放方面具有潜在的兴趣。因此，人们可以将不同的催化物种结合到不同的层中，以尝试在薄层形式内进行顺序催化的反应。 2)纳米粒子(NPs)的精确定位。由于NPs的对称定位已经取得了成功，现在建议探索精确的不对称定位，例如仍然在囊泡壁内，但比另一个界面(内部或外部)更接近其中一个界面。这对于外部和内部界面包含不同电晕链的囊泡是有意义的。其他可能包括一种NP定位在囊泡壁或胶束核心的疏水中心，另一种NP定位在囊泡的内外界面或胶束界面。这将特别引起人们的兴趣，因为它可能在催化中使用。 3)BC集合体的填充剂和释放剂。多组分释放将从包含两种或更多成分的单一系统或从平面或球形组件中进行探索，其中不同的组件位于不同的层中。在组合系统的寿命有限且释放速率需要较慢的条件下，相互作用的组件将是有意义的。 4)生物相容性和生物降解性聚合物的形态控制。最近制备的片层结构的释放特性将与球形聚集体的释放特性进行比较。 一旦成功完成，拟议的研究将使我们能够设计能够从亚微米级聚集体中控制成分释放的系统。如果需要，这些成分有可能在释放过程中发生催化化学反应，条件是产品在储存时降解可能是一个问题。对加拿大有特殊好处的潜在应用包括在农业或药理环境中的释放(和催化)。

The work focuses on block copolymer (BC) self-assembly in solution, to yield micelles, rods and especially vesicles, which combine relatively small size with space suitable for loading of both hydrophobic and hydrophilic materials; release profiles will be studied.  Other areas are the formation of nano-particles (NPs), their encapsulation and precise localization within BC aggregates (of interest in catalytic applications). 1) Layer-by-layer (LBL) assembly of various aggregates in sequential multilayers to yield planar nanostructures containing oppositely charged aggregate layers. Large vesicles can also serve as the base structure with surrounding alternating layers of oppositely charged small vesicles and/or micelles to create multilayered nano-capsules resembling blackberries. These structures are of potential interest in catalysis and in the controlled release of multiple ingredients. Thus, one could incorporate different catalytic species into different layers to attempt sequentially catalyzed reactions within a thin layer format. 2) Precise localization of nanoparticles (NPs). Since success has been achieved with symmetric localization of NPs, it is now proposed to explore precise asymmetric localization, e.g. still within a vesicle wall, but closer to one of the interfaces than the other (internal or external). This would be of interest for vesicles in which the exterior and interior interfaces contain different corona chains. Other possibilities include the localization of one type of NP in the hydrophobic center of the vesicle wall or micelle core, with another NP localized at the interior/exterior interface of the vesicle or at the micelle interface. This would be of special interest for for possible use in catalysis. 3) Filling and release of agents from BC aggregates. Multi-component release will be explored from either single systems containing two or more ingredients or from planar or spherical assemblies with the different components in different layers. Interacting components would be of interest under conditions where the combined system has a limited lifetime and the release rate needs to be slow. 4) Morphological control in biocompatible and biodegradable polymers. Release properties from recently prepared lamellar structures will be compared with those from spherical aggregates. Upon successful completion, the proposed research will allow us to design systems capable of controlled release of ingredients from sub-micron size aggregates. If desired it may be possible for those ingredients to undergo catalyzed chemical reactions in the release process under conditions were product degradation on storage may be a problem. Potential applications, with special benefits to Canada, include release (and catalysis) in agricultural or pharmacological settings.