Search for: All records

Abstract Ever since the inception of synthetic polymeric materials in the late 19th century, the number of studies on polymers as well as the complexity of their structures have only increased. The development and commercialization of new polymers with properties fine‐tuned for specific technological, environmental, consumer, or biomedical applications requires powerful analytical techniques that permit the in‐depth characterization of these materials. One such method with the ability to provide chemical composition and structure information with high sensitivity, selectivity, specificity, and speed is mass spectrometry (MS). This tutorial review presents and exemplifies the various MS techniques available for the elucidation of specific structural features in a synthetic polymer, including compositional complexity, primary structure, architecture, topology, and surface properties. Key to every MS analysis is sample conversion to gas‐phase ions. This review describes the fundamentals of the most suitable ionization methods for synthetic materials and provides relevant sample preparation protocols. Most importantly, structural characterizations via one‐step as well as hyphenated or multidimensional approaches are introduced and demonstrated with specific applications, including surface sensitive and imaging techniques. The aim of this tutorial review is to illustrate the capabilities of MS for the characterization of large, complex polymers and emphasize its potential as a powerful compositional and structural elucidation tool in polymer chemistry. 

Abstract Three sets of polyoxometalate (POM)‐based amphiphilic hybrid macromolecules with different rigidity in their organic tails are used as models to understand the effect of molecular rigidity on their possible self‐recognition feature during self‐assembly processes. Self‐recognition is achieved in the mixed solution of two structurally similar, sphere‐rigid T‐shape‐linked oligofluorene(TOF₄) rod amphiphiles, with the hydrophilic clusters being Anderson (Anderson‐TOF₄) and Dawson (Dawson‐TOF₄), respectively. Anderson‐TOF₄is observed to self‐assemble into onion‐like multilayer structures and Dawson‐TOF₄forms multilayer vesicles. The self‐assembly is controlled by the interdigitation of hydrophobic rods and the counterion‐mediated attraction among charged hydrophilic inorganic clusters. When the hydrophobic blocks are less rigid, e.g., partially rigid polystyrene and fully flexible alkyl chains, self‐recognition is not observed, attributing to the flexible conformation of hydrophobic molecules in the solvophobic domain. This study reveals that the self‐recognition among amphiphiles can be achieved by the geometrical limitation of the supramolecular structure due to the rigidity of solvophobic domains.