Genetically Directed Syntheses of New Polymeric Materials

分步和链生长聚合过程的统计性质确保了这种反应的产物必须是非均相的。因此，传统的聚合物材料由复杂的链状混合物组成，通常具有广泛的链长、序列和立体化学分布的特征。在许多材料应用中，这种分子异质性是可以接受的，在某些应用中，它是有利的，因为它可以抑制结晶并保持所需的性质，如光学清晰度、弹性或易于加工。另一方面，诸如Ziegler-Natta催化和活性聚合等能够更好地控制大分子结构的合成技术的发展，对聚合物科学和技术产生了深远的影响。在过去的十年中，包括PI在内的几个实验室利用细菌细胞的蛋白质生物合成装置的能力来制造基本上完全控制分子结构的新的大分子材料。这种方法最重要的优点似乎在于两个方面：i)。将材料特性与生物功能相结合，以及ii)。在小规模结构(有时称为纳米结构)的设计和制造中，分子结构的一致性是至关重要的。本提案针对后一个目标，特别关注含有与聚(g-苄基a，L-谷氨酸)(PBLG)相关的单分散大分子棒的体系的组装行为。这项研究是由材料研究部的聚合物项目和分子和细胞生物科学部的分子生物化学项目共同资助的。

The statistical nature of step and chain growth polymerization processes ensures that the products of such reactions must be heterogeneous. Conventional p9olymeric materials therefore consist of complex mixtures of chains, often characterized by broad distributions of chain length, sequence and stereochemistry. In many materials applications, this kind of molecular heterogeneity is acceptable, and in some applications it is advantageous, insofar as it may suppress crystallization and preserve desirable properties such as optical clarity, elasticity or ease of processing. On the other hand, synthetic developments that have afforded improved control of macromolecular architecture, such as Ziegler-Natta catalysis and living polymerization, have had profound impact on polymer science and technology.%%%Over the past decade, several laboratories - including the PI's - have exploited the capacity of the protein biosynthetic apparatus of bacterial cells to make new macromolecular materials characterized by essentially complete control of molecular architecture. The most important advantages of this method appear to lie in two areas: i). In the integration of material properties with biological function, and ii). In the design and fabrication of small-scale structures (sometimes called nanostructures), in which uniformity of molecular architecture is critical. This proposal addresses the latter objective, with a specific focus on the assembly behavior of systems containing monodisperse macromolecular rods related to poly (g-benzyl a,L-glutamate) (PBLG). This research is co-funded by the Polymers Program in the Division of Materials Research and the Molecular Biochemistry Program in the Division of Molecular and Cellular Biosciences.***