"Click" generation of a conjugated polymer library for SWNT dispersion

Noncovalent functionalization of single-walled carbon nanotubes (SWNTs) with conjugated polymers enhances SWNT processability and allows for selective dispersion of various SWNT species. Selective dispersions can be obtained by tuning the nature of the polymer, which can involve using various polymer backbones or side-chains. However, a clear understanding of selectivity determinants is elusive, as the degree of polymerization (DP) has a large effect on SWNT selectivity. Additionally, preparing libraries of conjugated polymers with varying functionality while keeping DP consistent is difficult. Here, we report the utilization of a strained cyclooctyne-containing conjugated polymer that serves as a versatile scaffold, enabling systematic preparation of a small library of conjugated polymers with different side-chain functionality, while maintaining a consistent DP. The resulting polymers were used as dispersants for SWNTs, forming supramolecular polymer-SWNT complexes that were characterized by UV-Vis-NIR absorption and Raman spectroscopy. In the series of polymers, we were able to probe the effect of small changes within the side chains, such as the incorporation of a carbonyl group or an aromatic unit, on the quality of the polymer-SWNT dispersion. The results of these studies provide new insight into the factors that dictate the ability of a polymer to form strong interactions with SWNTs. (C) 2018 Wiley Periodicals, Inc.

用共轭聚合物对单壁碳纳米管（SWNTs）进行非共价功能化可提高SWNT的可加工性，并能使各种SWNT种类选择性分散。通过调节聚合物的性质可获得选择性分散体，这可能涉及使用各种聚合物主链或侧链。然而，由于聚合度（DP）对SWNT选择性有很大影响，对选择性决定因素的清晰理解难以捉摸。此外，在保持DP一致的情况下制备具有不同官能团的共轭聚合物库是困难的。在此，我们报道了一种含应变环辛炔的共轭聚合物的应用，它可作为一种通用的支架，能够系统地制备具有不同侧链官能团的小型共轭聚合物库，同时保持DP一致。所得聚合物被用作SWNTs的分散剂，形成超分子聚合物 - SWNT复合物，通过紫外 - 可见 - 近红外吸收和拉曼光谱对其进行了表征。在这一系列聚合物中，我们能够探究侧链内的微小变化（例如羰基或芳香单元的引入）对聚合物 - SWNT分散质量的影响。这些研究结果为决定聚合物与SWNTs形成强相互作用能力的因素提供了新的见解。（C）2018威利期刊公司