Spectroscopy is the study of the interaction of matter with microwave (NMR), infrared (FTIR), and Visible (UV-vis) light. We can use various techniques to characterize polymers and identify the relationship between the polymer structures and their physical properties.
Depending on the experiment performed, NMR spectroscopy can be used to gather important information about the structure and molecular nature of the polymer system.
Identity of the polymer (types of monomers)
Polymer Impurities (e.g. solvents, catalyst, moisture, etc.)
End-group analysis to determine polymer size (Degree of polymerization, DP)
Functional groups present (e.g. from derivatization)
in situ Reactions and Polymerization Kinetics
Degree of branching
Ratio of monomers for copolymers
Variable Temperature experiments (‒80 °C to +120 °C)
Other Nuclei can also be detected by NMR to gather more information on the structural composition. The following nuclei can be used to run NMR spectroscopy experiments: 13C, 19F, 31P, 2H, 11B, 77Se, 15N, 29Si.
2D NMR can be used if the polymer requires a more thorough investigation in order to determine structural characteristics. For example, homonuclear (1H, 1H) COSY, TOCSY, NOESY, and heteronuclear (1H, 13C) HSQC, HMBC experiments are possible.
Purity of material
Detection of IR active functional group
Chemical fingerprint of compounds
UV-vis spectroscopy is a type of absorption spectroscopy where we can monitor the transition of from ground states to excited states.
Detect chromophores in sample
Calculate the molar absorptivity